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Harvey Sky N, Britnell J, Antwis R, Kartzinel T, Rubenstein D, Toye P, Karani B, Njeru R, Hinchcliffe D, Gaymer J, Mutisya S, Shultz S. Linking diet switching to reproductive performance across populations of two critically endangered mammalian herbivores. Commun Biol 2024; 7:333. [PMID: 38491117 PMCID: PMC10943211 DOI: 10.1038/s42003-024-05983-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 02/27/2024] [Indexed: 03/18/2024] Open
Abstract
Optimal foraging theory predicts that animals maximise energy intake by consuming the most valuable foods available. When resources are limited, they may include lower-quality fallback foods in their diets. As seasonal herbivore diet switching is understudied, we evaluate its extent and effects across three Kenyan reserves each for Critically Endangered eastern black rhino (Diceros bicornis michaeli) and Grevy's zebra (Equus grevyi), and its associations with habitat quality, microbiome variation, and reproductive performance. Black rhino diet breadth increases with vegetation productivity (NDVI), whereas zebra diet breadth peaks at intermediate NDVI. Black rhino diets associated with higher vegetation productivity have less acacia (Fabaceae: Vachellia and Senegalia spp.) and more grass suggesting that acacia are fallback foods, upending conventional assumptions. Larger dietary shifts are associated with longer calving intervals. Grevy's zebra diets in high rainfall areas are consistently grass-dominated, whereas in arid areas they primarily consume legumes during low vegetation productivity periods. Whilst microbiome composition between individuals is affected by the environment, and diet composition in black rhino, seasonal dietary shifts do not drive commensurate microbiome shifts. Documenting diet shifts across ecological gradients can increase the effectiveness of conservation by informing habitat suitability models and improving understanding of responses to resource limitation.
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Affiliation(s)
- Nick Harvey Sky
- Department of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9NT, UK.
- North of England Zoological Society, Chester Zoo, Upton-by-Chester, CH2 1LH, UK.
| | - Jake Britnell
- Department of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9NT, UK
- North of England Zoological Society, Chester Zoo, Upton-by-Chester, CH2 1LH, UK
| | - Rachael Antwis
- School of Environment and Life Sciences, University of Salford, Salford, M5 4WX, UK
| | - Tyler Kartzinel
- Department of Ecology, Evolution, and Organismal Biology, Brown University, 85 Waterman Street, Providence, RI, 02912, USA
- Institute at Brown for Environment and Society, Brown University, 85 Waterman Street, Providence, RI, 02912, USA
| | - Daniel Rubenstein
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, 08544-2016, USA
| | - Phil Toye
- International Livestock Research Institute and Centre for Tropical Livestock Genetics and Health, Nairobi, P.O. Box 30709-00100, Kenya
| | - Benedict Karani
- International Livestock Research Institute and Centre for Tropical Livestock Genetics and Health, Nairobi, P.O. Box 30709-00100, Kenya
| | - Regina Njeru
- International Livestock Research Institute and Centre for Tropical Livestock Genetics and Health, Nairobi, P.O. Box 30709-00100, Kenya
| | - Danielle Hinchcliffe
- School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, L3 3AF, UK
| | | | | | - Susanne Shultz
- Department of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9NT, UK
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2
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Lusseau D, Kindt-Larsen L, van Beest FM. Emergent interactions in the management of multiple threats to the conservation of harbour porpoises. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 855:158936. [PMID: 36152860 DOI: 10.1016/j.scitotenv.2022.158936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 09/09/2022] [Accepted: 09/18/2022] [Indexed: 06/16/2023]
Abstract
Human activities at sea are intensifying and diversifying. This is leading to more complex interactions of anthropogenic impacts requiring adaptable management interventions to mitigate their cumulative effects on biodiversity conservation and restoration objectives. Bycatch remains the dominant conservation threat for coastal cetaceans. Additionally, the indirect impact of repeated exposure to disturbances, particularly acoustic disturbances, can affect cetacean population growth and therefore conservation objectives. Pingers are used to ensonify nets to provide an effective mitigation of bycatch risk. As those become more prevalent across fisheries at risk to catch for example harbour porpoises, pingers become contributors to the anthropogenic noise landscape which may affect the vital rates of this species as well. Currently, we do not know how to best balance pinger prevalence to minimise both bycatch rate and the population consequences of acoustic disturbance (PCoD). Here we use an agent-based model to determine how pinger prevalence in nets can be adjusted to minimise bycatch rate and noise disturbance propagating to affect population growth for harbour porpoises. We show that counter-intuitively bycatch rate can increase at lower pinger prevalence. When ecological conditions are such that PCOD can emerge, higher prevalence of pingers can lead to indirect effects on population growth. This would result from condition-mediated decreased reproductive potential. Displacing fishing effort, via time-area closure, can be an effective mitigation strategy in these circumstances. These findings have important implications for current management plans which, for practical consideration, may lead to lower overall pinger prevalence at sea. This study also shows that estimating the reproductive potential of the species should be incorporated in bycatch monitoring programmes. We now need to better understand how physiological condition affect reproductive decisions and behavioural responses to noise in cetaceans to better appraise and estimate the cumulative impacts of bycatch and its mitigations.
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Affiliation(s)
- David Lusseau
- National Institute for Aquatic Resources, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.
| | - Lotte Kindt-Larsen
- National Institute for Aquatic Resources, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Floris M van Beest
- Department of Bioscience, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark
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3
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Proposing a framework for monitoring demographic parameters in local cetacean populations: the case of short-finned pilot whales in Madeira. Mamm Biol 2022. [DOI: 10.1007/s42991-022-00266-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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4
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Bottlenose Dolphin Responses to Boat Traffic Affected by Boat Characteristics and Degree of Compliance to Code of Conduct. SUSTAINABILITY 2022. [DOI: 10.3390/su14095185] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Levels of boat traffic in coastal seas have been steadily increasing in many parts of the world, introducing pressures on marine wildlife through disturbance. The appropriate management of human activities is important not only to preserve wildlife, but also for the local communities that depend on ecotourism for employment and their economy. This study presents further insight into bottlenose dolphin (Tursiops truncatus) responses to boats in New Quay Bay (West Wales) within the Cardigan Bay Special Area of Conservation. This region is heavily dependent on wildlife tourism, and marine traffic is regulated through a long-standing Code of Conduct. Based on a long-term dataset spanning the months of April to October and the years 2010–2018, the study found that compliance to a code of human behaviour increased dolphin positive responses towards boats. Dolphin responses to individual named boats and to different boat types were examined in greater detail. Speed boats, small motorboats, and kayaks were found to break the code most often, resulting in higher rates of negative response by dolphins. Visitor passenger boats formed the majority of boat traffic in the area, and showed greater compliance than other general recreational crafts. Suggestions are made for the better protection of the coastal dolphin population, as well as the role that citizen science can play to help achieve this goal through working directly with wildlife trip boats and the recruitment of local observers.
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5
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Pirotta E. A review of bioenergetic modelling for marine mammal populations. CONSERVATION PHYSIOLOGY 2022; 10:coac036. [PMID: 35754757 PMCID: PMC9215292 DOI: 10.1093/conphys/coac036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 03/07/2022] [Accepted: 06/15/2022] [Indexed: 05/16/2023]
Abstract
Bioenergetic models describe the processes through which animals acquire energy from resources in the environment and allocate it to different life history functions. They capture some of the fundamental mechanisms regulating individuals, populations and ecosystems and have thus been used in a wide variety of theoretical and applied contexts. Here, I review the development of bioenergetic models for marine mammals and their application to management and conservation. For these long-lived, wide-ranging species, bioenergetic approaches were initially used to assess the energy requirements and prey consumption of individuals and populations. Increasingly, models are developed to describe the dynamics of energy intake and allocation and predict how resulting body reserves, vital rates and population dynamics might change as external conditions vary. The building blocks required to develop such models include estimates of intake rate, maintenance costs, growth patterns, energy storage and the dynamics of gestation and lactation, as well as rules for prioritizing allocation. I describe how these components have been parameterized for marine mammals and highlight critical research gaps. Large variation exists among available analytical approaches, reflecting the large range of life histories, management needs and data availability across studies. Flexibility in modelling strategy has supported tailored applications to specific case studies but has resulted in limited generality. Despite the many empirical and theoretical uncertainties that remain, bioenergetic models can be used to predict individual and population responses to environmental change and other anthropogenic impacts, thus providing powerful tools to inform effective management and conservation.
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Affiliation(s)
- Enrico Pirotta
- Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews KY16 9LZ, UK. Tel: (+44) (0)1334 461 842.
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6
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John JS, Thometz NM, Boerner K, Denum L, Kendall TL, Richter BP, Gaspard JC, Williams TM. Metabolic trade-offs in tropical and subtropical marine mammals: unique maintenance and locomotion costs in West Indian manatees and Hawaiian monk seals. J Exp Biol 2021; 224:271210. [PMID: 34357378 PMCID: PMC8353161 DOI: 10.1242/jeb.237628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 06/09/2021] [Indexed: 11/20/2022]
Abstract
Unlike the majority of marine mammal species, Hawaiian monk seals (Neomonachus schauinslandi) and West Indian manatees (Trichechus manatus latirostris) reside exclusively in tropical or subtropical waters. Although potentially providing an energetic benefit through reduced maintenance and thermal costs, little is known about the cascading effects that may alter energy expenditure during activity, dive responses and overall energy budgets for these warm-water species. To examine this, we used open-flow respirometry to measure the energy expended during resting and swimming in both species. We found that the average resting metabolic rates (RMRs) for both the adult monk seal (753.8±26.1 kJ h-1, mean±s.e.m.) and manatees (887.7±19.5 kJ h-1) were lower than predicted for cold-water marine mammal species of similar body mass. Despite these relatively low RMRs, both total cost per stroke and total cost of transport (COTTOT) during submerged swimming were similar to predictions for comparably sized marine mammals (adult monk seal: cost per stroke=5.0±0.2 J kg-1 stroke-1, COTTOT=1.7±0.1 J kg-1 m-1; manatees: cost per stroke=2.0±0.4 J kg-1 stroke-1, COTTOT=0.87±0.17 J kg-1 m-1). These lower maintenance costs result in less variability in adjustable metabolic costs that occur during submergence for warm-water species. However, these reduced maintenance costs do not appear to confer an advantage in overall energetic costs during activity, potentially limiting the capacity of warm-water species to respond to anthropogenic or environmental threats that require increased energy expenditure.
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Affiliation(s)
- Jason S John
- University of California Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Nicole M Thometz
- University of California Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95060, USA.,University of San Francisco, 2130 Fulton Street, San Francisco, CA 94117, USA
| | - Katharine Boerner
- Mote Marine Laboratory & Aquarium, 1600 Ken Thompson Pkwy, Sarasota, FL 34236, USA
| | - Laura Denum
- Mote Marine Laboratory & Aquarium, 1600 Ken Thompson Pkwy, Sarasota, FL 34236, USA
| | - Traci L Kendall
- University of California Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Beau P Richter
- University of California Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95060, USA
| | - Joseph C Gaspard
- Pittsburgh Zoo & PPG Aquarium, One Wild Place, Pittsburgh, PA 15206, USA
| | - Terrie M Williams
- University of California Santa Cruz, Coastal Biology Building, 130 McAllister Way, Santa Cruz, CA 95060, USA
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7
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Barocas A, Farfan J, Groenendijk J, Mendoza J, Silva J, Mujica O, Ochoa JA, Macdonald DW, Swaisgood RR. Disturbance‐specific behavioral responses of giant otters exposed to ecotourism and extractive activities. Anim Conserv 2021. [DOI: 10.1111/acv.12713] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- A. Barocas
- Recovery Ecology San Diego Zoo Wildlife Alliance Escondido CA USA
- Wildlife Conservation Research Unit Department of Zoology The Recanati‐Kaplan Centre University of Oxford Abingdon UK
- San Diego Zoo Global‐Peru Cusco Peru
| | - J. Farfan
- Frankfurt Zoological Society – Perú Cusco Peru
- Facultad de Ciencias Universidad Nacional de San Antonio Abad del Cusco Cusco Peru
| | | | - J. Mendoza
- National Service of Protected Natural Areas (SERNANP) Cusco Peru
| | - J. Silva
- Frankfurt Zoological Society – Perú Cusco Peru
| | - O. Mujica
- Frankfurt Zoological Society – Perú Cusco Peru
| | - J. A. Ochoa
- Facultad de Ciencias Universidad Nacional de San Antonio Abad del Cusco Cusco Peru
- Museo de Biodiversidad del Perú Cusco Peru
| | - D. W. Macdonald
- Wildlife Conservation Research Unit Department of Zoology The Recanati‐Kaplan Centre University of Oxford Abingdon UK
| | - R. R. Swaisgood
- Recovery Ecology San Diego Zoo Wildlife Alliance Escondido CA USA
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8
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Currie JJ, van Aswegen M, Stack SH, West KL, Vivier F, Bejder L. Rapid weight loss in free ranging pygmy killer whales (Feresa attenuata) and the implications for anthropogenic disturbance of odontocetes. Sci Rep 2021; 11:8181. [PMID: 33854117 PMCID: PMC8046785 DOI: 10.1038/s41598-021-87514-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 03/30/2021] [Indexed: 11/09/2022] Open
Abstract
Understanding the impacts of foraging disruptions to odontocete body condition is fundamental to quantifying biological effects of human disturbance and environmental changes on cetacean populations. Here, reductions in body volume of free-ranging pygmy killer whales (Feresa attenuata) were calculated using repeated measurements of the same individuals obtained through Unoccupied Aerial System (UAS)-photogrammetry during a prolonged disruption in foraging activity arising from a 21-day stranding event. Stranded individuals were used to verify UAS-derived volume and length estimates through 3D-imaging, water displacement, and post-mortem measurements. We show that (a) UAS estimates of length were within 1.5% of actual body length and UAS volume estimates were within 10-13% of actual volume, (b) foraging disruption resulted in a daily decrease of 2% of total body mass/day, and (c) pygmy killer whales can lose up to 27% of their total body weight within 17 days. These findings highlight the use of UAS as a promising new method to remotely monitor changes in body condition and animal health, which can be used to determine the potential effects of anthropogenic disturbance and environmental change on free-ranging odontocetes.
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Affiliation(s)
| | - Martin van Aswegen
- Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii at Manoa, Kaneohe, HI, USA
| | | | - Kristi L West
- Hawaii Institute of Marine Biology, Kaneohe, HI, USA
- Human Nutrition Food and Animal Sciences, College of Tropical Agriculture and Human Resources, Honolulu, HI, USA
| | - Fabien Vivier
- Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii at Manoa, Kaneohe, HI, USA
| | - Lars Bejder
- Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii at Manoa, Kaneohe, HI, USA
- Zoophysiology, Department of Biology, Aarhus University, Aarhus, Denmark
- Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, Murdoch, WA, Australia
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9
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Assessment on the effectiveness of vessel-approach regulations to protect cetaceans in Australia: A review on behavioral impacts with case study on the threatened Burrunan dolphin (Tursiops australis). PLoS One 2021; 16:e0243353. [PMID: 33465088 PMCID: PMC7815133 DOI: 10.1371/journal.pone.0243353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 11/19/2020] [Indexed: 12/04/2022] Open
Abstract
Vessels cause considerable disturbance to cetaceans world-wide, with potential long-term impacts to population viability. Here we present a comprehensive review of vessel impacts to cetacean behavior in Australian waters (2003–2015), finding inadequate protections to be in place. The majority of these studies found trends of decreased animal travel and resting behavioral states as well as low compliance to regulations, and they recommended further regulatory action such as greater enforcement or monitoring, or passive management strategies. As a case study, we conducted the first field assessment of vessel compliance with the Wildlife (Marine Mammal) Regulations 2009 in Gippsland Lakes, Australia, and provide the first assessment of the endangered Gippsland Lakes Burrunan dolphin (Tursiops australis) population’s behavioral ecology. Dolphin behavior and vessel regulation compliance data were collected during boat-based surveys of Gippsland Lakes from July 2017 to January 2018, with a total of 22 dolphin group sightings resulting in 477 five-minute point samples. 77% of dolphin sightings involved vessel interactions (within 400 m), and 56 regulation breaches were observed. These breaches were most severe in summer (mean = 4.54 breaches/hour). Vessels were found to alter dolphin behavior before, during, and after interactions and regulation breaches, including increased mating (mate guarding) and milling behavioral states, and increased ‘fish catch’, ‘high leap’ and ‘tail slap’ behavioral events. These behavioral changes may indicate masking of the dolphins' acoustic communication, disturbance of prey, increased dolphin transition behaviors, and/or induced stress and changes to group structure (including increased mate guarding). While our results provide evidence of short-term altered behavior, the potential for long-term effects on population dynamics for this threatened species is high. In the context of reported inadequate cetacean protection Australia-wide, our management recommendations include greater monitoring and enforcement, and the utilisation of adaptive management.
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10
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Papafitsoros K, Panagopoulou A, Schofield G. Social media reveals consistently disproportionate tourism pressure on a threatened marine vertebrate. Anim Conserv 2020. [DOI: 10.1111/acv.12656] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- K. Papafitsoros
- ARCHELON The Sea Turtle Protection Society of Greece Athens Greece
- Weierstrass Institute Berlin Germany
| | - A. Panagopoulou
- ARCHELON The Sea Turtle Protection Society of Greece Athens Greece
- The Leatherback Trust Fort Wayne IN USA
| | - G. Schofield
- School of Biological and Chemical Sciences Queen Mary University of London London UK
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11
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Effects of intense storm events on dolphin occurrence and foraging behavior. Sci Rep 2020; 10:19247. [PMID: 33159135 PMCID: PMC7648104 DOI: 10.1038/s41598-020-76077-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 10/22/2020] [Indexed: 11/08/2022] Open
Abstract
As storms become increasingly intense and frequent due to climate change, we must better understand how they alter environmental conditions and impact species. However, storms are ephemeral and provide logistical challenges that prevent visual surveys commonly used to understand marine mammal ecology. Thus, relatively little is known about top predators’ responses to such environmental disturbances. In this study, we utilized passive acoustic monitoring to characterize the response of bottlenose dolphins to intense storms offshore Maryland, USA between 2015 and 2017. During and following four autumnal storms, dolphins were detected less frequently and for shorter periods of time. However, dolphins spent a significantly higher percentage of their encounters feeding after the storm than they did before or during. This change in foraging may have resulted from altered distributions and behavior of their prey species, which are prone to responding to environmental changes, such as varied sea surface temperatures caused by storms. It is increasingly vital to determine how these intense storms alter oceanography, prey movements, and the behavior of top predators.
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12
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Food-provisioning negatively affects calf survival and female reproductive success in bottlenose dolphins. Sci Rep 2019; 9:8981. [PMID: 31222088 PMCID: PMC6586622 DOI: 10.1038/s41598-019-45395-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 06/03/2019] [Indexed: 11/08/2022] Open
Abstract
Food-provisioning of wildlife can facilitate reliable up-close encounters desirable by tourists and, consequently, tour operators. Food-provisioning can alter the natural behavior of an animal, encouraging adverse behavior (e.g. begging for food handouts), and affect the reproductive success and the viability of a population. Studies linking food-provisioning to reproductive success are limited due to the lack of long-term datasets available, especially for long-lived species such as marine mammals. In Bunbury, Western Australia, a state-licensed food-provisioning program offers fish handouts to a limited number of free-ranging bottlenose dolphins (Tursiops aduncus). Coupled with long-term historical data, this small (<200 individuals), resident dolphin population has been extensively studied for over ten years, offering an opportunity to examine the effect of food-provisioning on the reproductive success of females (ntotal = 63; nprovisioned females = 8). Female reproductive success was estimated as the number of weaned calves produced per reproductive years and calf survival at year one and three years old was investigated. The mean reproductive success of provisioned and non-provisioned females was compared using Bayes factor. We also used generalized linear models (GLMs) to examine female reproductive success in relation to the occurrence of food-provisioning, begging behavior and location (within the study area). Furthermore, we examined the influence of these variables and birth order and climatic fluctuations (e.g. El Niño Southern Oscillation) on calf survival. Bayes factor analyses (Bayes factor = 6.12) and results from the best fitting GLMs showed that female reproductive success and calf survival were negatively influenced by food-provisioning. The negative effects of food-provisioning, although only affecting a small proportion of the adult females’ population (13.2%), are of concern, especially given previous work showing that this population is declining.
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13
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Wisniewska DM, Johnson M, Teilmann J, Siebert U, Galatius A, Dietz R, Madsen PT. High rates of vessel noise disrupt foraging in wild harbour porpoises ( Phocoena phocoena). Proc Biol Sci 2019; 285:rspb.2017.2314. [PMID: 29445018 DOI: 10.1098/rspb.2017.2314] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 01/22/2018] [Indexed: 11/12/2022] Open
Abstract
Shipping is the dominant marine anthropogenic noise source in the world's oceans, yet we know little about vessel encounter rates, exposure levels and behavioural reactions for cetaceans in the wild, many of which rely on sound for foraging, communication and social interactions. Here, we used animal-borne acoustic tags to measure vessel noise exposure and foraging efforts in seven harbour porpoises in highly trafficked coastal waters. Tagged porpoises encountered vessel noise 17-89% of the time and occasional high-noise levels coincided with vigorous fluking, bottom diving, interrupted foraging and even cessation of echolocation, leading to significantly fewer prey capture attempts at received levels greater than 96 dB re 1 µPa (16 kHz third-octave). If such exposures occur frequently, porpoises, which have high metabolic requirements, may be unable to compensate energetically with negative long-term fitness consequences. That shipping noise disrupts foraging in the high-frequency-hearing porpoise raises concerns that other toothed whale species may also be affected.
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Affiliation(s)
- Danuta Maria Wisniewska
- Department of Bioscience, Aarhus University, Aarhus, Denmark .,Hopkins Marine Station, Stanford University, Pacific Grove, CA, USA
| | - Mark Johnson
- Sea Mammal Research Unit, University of St Andrews, St Andrews, UK
| | - Jonas Teilmann
- Department of Bioscience, Aarhus University, Aarhus, Denmark
| | - Ursula Siebert
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover, Buesum, Germany
| | - Anders Galatius
- Department of Bioscience, Aarhus University, Aarhus, Denmark
| | - Rune Dietz
- Department of Bioscience, Aarhus University, Aarhus, Denmark
| | - Peter Teglberg Madsen
- Department of Bioscience, Aarhus University, Aarhus, Denmark.,Aarhus Institute of Advanced Studies, Aarhus University, Aarhus, Denmark
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14
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Arso Civil M, Cheney B, Quick NJ, Islas‐Villanueva V, Graves JA, Janik VM, Thompson PM, Hammond PS. Variations in age- and sex-specific survival rates help explain population trend in a discrete marine mammal population. Ecol Evol 2019; 9:533-544. [PMID: 30680134 PMCID: PMC6342117 DOI: 10.1002/ece3.4772] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 10/31/2018] [Accepted: 11/02/2018] [Indexed: 11/22/2022] Open
Abstract
Understanding the drivers underlying fluctuations in the size of animal populations is central to ecology, conservation biology, and wildlife management. Reliable estimates of survival probabilities are key to population viability assessments, and patterns of variation in survival can help inferring the causal factors behind detected changes in population size. We investigated whether variation in age- and sex-specific survival probabilities could help explain the increasing trend in population size detected in a small, discrete population of bottlenose dolphins Tursiops truncatus off the east coast of Scotland. To estimate annual survival probabilities, we applied capture-recapture models to photoidentification data collected from 1989 to 2015. We used robust design models accounting for temporary emigration to estimate juvenile and adult survival, multistate models to estimate sex-specific survival, and age models to estimate calf survival. We found strong support for an increase in juvenile/adult annual survival from 93.1% to 96.0% over the study period, most likely caused by a change in juvenile survival. Examination of sex-specific variation showed weaker support for this trend being a result of increasing female survival, which was overall higher than for males and animals of unknown sex. Calf survival was lower in the first than second year; a bias in estimating third-year survival will likely exist in similar studies. There was some support first-born calf survival being lower than for calves born subsequently. Coastal marine mammal populations are subject to the impacts of environmental change, increasing anthropogenic disturbance and the effects of management measures. Survival estimates are essential to improve our understanding of population dynamics and help predict how future pressures may impact populations, but obtaining robust information on the life history of long-lived species is challenging. Our study illustrates how knowledge of survival can be increased by applying a robust analytical framework to photoidentification data.
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Affiliation(s)
- Mònica Arso Civil
- Sea Mammal Research Unit, Scottish Oceans InstituteUniversity of St AndrewsSt AndrewsUK
| | - Barbara Cheney
- Lighthouse Field Station, Institute of Biological and Environmental SciencesUniversity of AberdeenCromartyUK
| | - Nicola J. Quick
- Sea Mammal Research Unit, Scottish Oceans InstituteUniversity of St AndrewsSt AndrewsUK
- Duke University Marine LaboratoryNicholas School of the EnvironmentBeaufortNorth Carolina
| | - Valentina Islas‐Villanueva
- Sea Mammal Research Unit, Scottish Oceans InstituteUniversity of St AndrewsSt AndrewsUK
- CONACYT, Universidad del Mar, Instituto de GenéticaCiudad UniversitariaOaxacaMéxico
| | - Jeff A. Graves
- Centre for Biological DiversityUniversity of St AndrewsSt AndrewsUK
| | - Vincent M. Janik
- Sea Mammal Research Unit, Scottish Oceans InstituteUniversity of St AndrewsSt AndrewsUK
| | - Paul M. Thompson
- Lighthouse Field Station, Institute of Biological and Environmental SciencesUniversity of AberdeenCromartyUK
| | - Philip S. Hammond
- Sea Mammal Research Unit, Scottish Oceans InstituteUniversity of St AndrewsSt AndrewsUK
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Manlik O. The Importance of Reproduction for the Conservation of Slow-Growing Animal Populations. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1200:13-39. [PMID: 31471793 DOI: 10.1007/978-3-030-23633-5_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Both survival and reproduction are important fitness components, and thus critical to the viability of wildlife populations. Preventing one death (survival) or contributing one newborn (reproduction), has arguably the same effect on population dynamics-in each instance the population grows or is maintained by one additional member. However, for the conservation of slow-growing animal populations, the importance of reproduction is sometimes overlooked when evaluating wildlife management options. This has to do with the use of demographic sensitivity analyses, which quantify the relative contribution of vital rates to population growth. For slow-growing populations, the results of such analyses typically show that growth rates are more sensitive to changes in survival than to equal proportional changes in reproduction. Consequently, for slow-growing taxa, survival has been labelled a better fitness surrogate than reproduction. However, such a generalization, derived from conventional sensitivity analyses, is based on flawed approaches, such as omitting appropriate scaling of vital rates, and sometimes misinterpretations. In this chapter, I make the case that for the conservation of slow-growing species the role of reproduction is considerably greater than conventional sensitivity analyses would suggest. This is illustrated by case studies on wildlife populations that underscore the importance of reproduction for the conservation of slow-growing birds, ungulates, carnivores, and cetaceans.
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Affiliation(s)
- Oliver Manlik
- Biology Department, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates. .,Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW, Australia.
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16
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Joy R, Wood JD, Sparling CE, Tollit DJ, Copping AE, McConnell BJ. Empirical measures of harbor seal behavior and avoidance of an operational tidal turbine. MARINE POLLUTION BULLETIN 2018; 136:92-106. [PMID: 30509846 DOI: 10.1016/j.marpolbul.2018.08.052] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 07/10/2018] [Accepted: 08/23/2018] [Indexed: 06/09/2023]
Abstract
There is global interest in marine renewable energy from underwater tidal turbines. Due to overlap in animal habitat with locations for tidal turbines, the potential for collisions has led to concern around strike risk. Using data from tagged harbor seals collected before construction and after operation of the SeaGen tidal turbine in Northern Ireland, this study quantifies risks of an operational turbine to harbor seals by taking into account turbine characteristics, tidal state, and seal behavior. We found 68% spatial avoidance (95% C.I., 37%, 83%) by harbor seals within 200 m of the turbine. When additionally accounting for variation in seal occupancy over depth and tidal flows, there is an overall reduction in collision risk from 1.29 to 0.125 seals per tidal cycle (90.3% reduction; (95% C.I., 83%, 98%)) compared to risk calculated under assumptions of uniform habitat use. This demonstrates the need to incorporate environmental conditions to properly assess strike risk.
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Affiliation(s)
- Ruth Joy
- SMRU Consulting Canada, Suite 510, 1529 6th Avenue West, Vancouver, BC V6J 1R1, Canada; Department of Statistics and Actuarial Science, Simon Fraser University, Burnaby, BC V5A 1S6, Canada.
| | - Jason D Wood
- SMRU Consulting USA, PO Box 764, Friday Harbor, WA 98250, USA
| | - Carol E Sparling
- SMRU Consulting Europe, New Technology Centre, North Haugh, St Andrews, Fife KY16 9SR, Scotland
| | - Dom J Tollit
- SMRU Consulting Canada, Suite 510, 1529 6th Avenue West, Vancouver, BC V6J 1R1, Canada
| | - Andrea E Copping
- Pacific Northwest National Laboratory, 1100 Dexter Ave N, Suite 400, Seattle, WA, USA
| | - Bernie J McConnell
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St. Andrews, St. Andrews, Fife KY16 8LB, Scotland
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17
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Tyne JA, Christiansen F, Heenehan HL, Johnston DW, Bejder L. Chronic exposure of Hawaii Island spinner dolphins ( Stenella longirostris) to human activities. ROYAL SOCIETY OPEN SCIENCE 2018; 5:171506. [PMID: 30473795 PMCID: PMC6227997 DOI: 10.1098/rsos.171506] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 09/24/2018] [Indexed: 06/09/2023]
Abstract
Habitat selection is strongly influenced by spatial variations in habitat quality and predation risk. Repeated exposure of wildlife to anthropogenic activities in important habitats may affect habitat selection, leading to negative biological consequences. We quantified the cumulative human exposure of a small, genetically isolated and behaviourally constrained spinner dolphin (Stenella longirostris) population, off Hawaii Island, and exposure effects on their daytime cumulative activity budget. Dolphins were exposed to human activities within 100 m for 82.7% of the daytime, with a median duration of 10 min between exposure events. Individual dolphins spent on average 61.7% (s.d. = 6.5) of their daytime resting. Of their total rest time, greater than 90% occurred inside sheltered bays. Despite high levels of human exposure, we did not observe an effect on dolphin resting behaviour. The short intervals between exposure events probably prevent dolphins from returning to a natural resting state before the next event. Consequently, 'control' observations may represent a resting behaviour of a more vigilant nature. Chronic levels of exposure to human activities could lead to rest deprivation, displacement from preferred resting habitats and ultimately negative population level effects. These results have implications for new proposed legislation aiming to reduce dolphin exposure to human activities.
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Affiliation(s)
- Julian A. Tyne
- Aquatic Megafauna Research Unit, School of Veterinary and Life Sciences, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia
| | - Fredrik Christiansen
- Aquatic Megafauna Research Unit, School of Veterinary and Life Sciences, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia
| | - Heather L. Heenehan
- Division of Marine Science and Conservation, Nicholas School of the Environment, Duke University Marine Lab, 135 Duke Marine Lab Road, Beaufort, NC, USA
| | - David W. Johnston
- Aquatic Megafauna Research Unit, School of Veterinary and Life Sciences, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia
- Division of Marine Science and Conservation, Nicholas School of the Environment, Duke University Marine Lab, 135 Duke Marine Lab Road, Beaufort, NC, USA
| | - Lars Bejder
- Aquatic Megafauna Research Unit, School of Veterinary and Life Sciences, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia
- Division of Marine Science and Conservation, Nicholas School of the Environment, Duke University Marine Lab, 135 Duke Marine Lab Road, Beaufort, NC, USA
- Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii, Hawaii, HI, USA
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18
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McHuron EA, Schwarz LK, Costa DP, Mangel M. A state-dependent model for assessing the population consequences of disturbance on income-breeding mammals. Ecol Modell 2018. [DOI: 10.1016/j.ecolmodel.2018.07.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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19
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Pirotta E, Booth CG, Costa DP, Fleishman E, Kraus SD, Lusseau D, Moretti D, New LF, Schick RS, Schwarz LK, Simmons SE, Thomas L, Tyack PL, Weise MJ, Wells RS, Harwood J. Understanding the population consequences of disturbance. Ecol Evol 2018; 8:9934-9946. [PMID: 30386587 PMCID: PMC6202709 DOI: 10.1002/ece3.4458] [Citation(s) in RCA: 120] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 07/12/2018] [Accepted: 07/14/2018] [Indexed: 11/25/2022] Open
Abstract
Managing the nonlethal effects of disturbance on wildlife populations has been a long-term goal for decision makers, managers, and ecologists, and assessment of these effects is currently required by European Union and United States legislation. However, robust assessment of these effects is challenging. The management of human activities that have nonlethal effects on wildlife is a specific example of a fundamental ecological problem: how to understand the population-level consequences of changes in the behavior or physiology of individual animals that are caused by external stressors. In this study, we review recent applications of a conceptual framework for assessing and predicting these consequences for marine mammal populations. We explore the range of models that can be used to formalize the approach and we identify critical research gaps. We also provide a decision tree that can be used to select the most appropriate model structure given the available data. Synthesis and applications: The implementation of this framework has moved the focus of discussion of the management of nonlethal disturbances on marine mammal populations away from a rhetorical debate about defining negligible impact and toward a quantitative understanding of long-term population-level effects. Here we demonstrate the framework's general applicability to other marine and terrestrial systems and show how it can support integrated modeling of the proximate and ultimate mechanisms that regulate trait-mediated, indirect interactions in ecological communities, that is, the nonconsumptive effects of a predator or stressor on a species' behavior, physiology, or life history.
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Affiliation(s)
- Enrico Pirotta
- Department of Mathematics and StatisticsWashington State UniversityVancouverWashington
- School of Biological, Earth and Environmental SciencesUniversity College CorkCorkIreland
| | | | - Daniel P. Costa
- Department of Ecology and Evolutionary BiologyUniversity of CaliforniaSanta CruzCalifornia
| | - Erica Fleishman
- Department of Environmental Science and PolicyUniversity of CaliforniaDavisCalifornia
- Department of Fish, Wildlife and Conservation BiologyColorado State UniversityFort CollinsColorado
| | - Scott D. Kraus
- Anderson‐Cabot Center for Ocean LifeNew England AquariumBostonMassachusetts
| | - David Lusseau
- School of Biological SciencesUniversity of AberdeenAberdeenUK
| | | | - Leslie F. New
- Department of Mathematics and StatisticsWashington State UniversityVancouverWashington
| | - Robert S. Schick
- Duke UniversityDurhamNorth Carolina
- Centre for Research into Ecological and Environmental ModellingUniversity of St AndrewsSt AndrewsUK
| | - Lisa K. Schwarz
- Institute of Marine SciencesUniversity of CaliforniaSanta CruzCalifornia
| | | | - Len Thomas
- Centre for Research into Ecological and Environmental ModellingUniversity of St AndrewsSt AndrewsUK
| | - Peter L. Tyack
- Sea Mammal Research UnitScottish Oceans InstituteSchool of BiologyUniversity of St AndrewsSt AndrewsUK
| | - Michael J. Weise
- Office of Naval ResearchMarine Mammal & Biology ProgramArlingtonVirginia
| | - Randall S. Wells
- Chicago Zoological Society's Sarasota Dolphin Research Programc/o Mote Marine LaboratorySarasotaFlorida
| | - John Harwood
- Centre for Research into Ecological and Environmental ModellingUniversity of St AndrewsSt AndrewsUK
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20
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Erbe C, Dunlop R, Dolman S. Effects of Noise on Marine Mammals. EFFECTS OF ANTHROPOGENIC NOISE ON ANIMALS 2018. [DOI: 10.1007/978-1-4939-8574-6_10] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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21
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Udevitz MS, Jay CV, Taylor RL, Fischbach AS, Beatty WS, Noren SR. Forecasting consequences of changing sea ice availability for Pacific walruses. Ecosphere 2017. [DOI: 10.1002/ecs2.2014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Mark S. Udevitz
- Alaska Science Center, U.S. Geological Survey 4210 University Drive Anchorage Alaska 99508 USA
| | - Chadwick V. Jay
- Alaska Science Center, U.S. Geological Survey 4210 University Drive Anchorage Alaska 99508 USA
| | - Rebecca L. Taylor
- Alaska Science Center, U.S. Geological Survey 4210 University Drive Anchorage Alaska 99508 USA
| | - Anthony S. Fischbach
- Alaska Science Center, U.S. Geological Survey 4210 University Drive Anchorage Alaska 99508 USA
| | - William S. Beatty
- U.S. Fish and Wildlife Service, Marine Mammals Management 1011 East Tudor Road Anchorage Alaska 99503 USA
| | - Shawn R. Noren
- Institute of Marine Science University of California, Santa Cruz 100 Shaffer Road Santa Cruz California 95060 USA
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22
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Bejarano AC, Wells RS, Costa DP. Development of a bioenergetic model for estimating energy requirements and prey biomass consumption of the bottlenose dolphin Tursiops truncatus. Ecol Modell 2017. [DOI: 10.1016/j.ecolmodel.2017.05.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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23
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Filby NE, Christiansen F, Scarpaci C, Stockin KA. Effects of swim-with-dolphin tourism on the behaviour of a threatened species, the Burrunan dolphin Tursiops australis. ENDANGER SPECIES RES 2017. [DOI: 10.3354/esr00826] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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24
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Lesage V, Omrane A, Doniol-Valcroze T, Mosnier A. Increased proximity of vessels reduces feeding opportunities of blue whales in the St. Lawrence Estuary, Canada. ENDANGER SPECIES RES 2017. [DOI: 10.3354/esr00825] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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25
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26
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Friedlaender AS, Hazen EL, Goldbogen JA, Stimpert AK, Calambokidis J, Southall BL. Prey-mediated behavioral responses of feeding blue whales in controlled sound exposure experiments. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:1075-1085. [PMID: 27509749 DOI: 10.1002/15-0783] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Behavioral response studies provide significant insights into the nature, magnitude, and consequences of changes in animal behavior in response to some external stimulus. Controlled exposure experiments (CEEs) to study behavioral response have faced challenges in quantifying the importance of and interaction among individual variability, exposure conditions, and environmental covariates. To investigate these complex parameters relative to blue whale behavior and how it may change as a function of certain sounds, we deployed multi-sensor acoustic tags and conducted CEEs using simulated mid-frequency active sonar (MFAS) and pseudo-random noise (PRN) stimuli, while collecting synoptic, quantitative prey measures. In contrast to previous approaches that lacked such prey data, our integrated approach explained substantially more variance in blue whale dive behavioral responses to mid-frequency sounds (r2 = 0.725 vs. 0.14 previously). Results demonstrate that deep-feeding whales respond more clearly and strongly to CEEs than those in other behavioral states, but this was only evident with the increased explanatory power provided by incorporating prey density and distribution as contextual covariates. Including contextual variables increases the ability to characterize behavioral variability and empirically strengthens previous findings that deep-feeding blue whales respond significantly to mid-frequency sound exposure. However, our results are only based on a single behavioral state with a limited sample size, and this analytical framework should be applied broadly across behavioral states. The increased capability to describe and account for individual response variability by including environmental variables, such as prey, that drive foraging behavior underscores the importance of integrating these and other relevant contextual parameters in experimental designs. Our results suggest the need to measure and account for the ecological dynamics of predator-prey interactions when studying the effects of anthropogenic disturbance in feeding animals.
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27
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Nattrass S, Lusseau D. Using resilience to predict the effects of disturbance. Sci Rep 2016; 6:25539. [PMID: 27145918 PMCID: PMC4857141 DOI: 10.1038/srep25539] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 04/18/2016] [Indexed: 11/20/2022] Open
Abstract
Animal behaviour emerges from a complex interaction between an individual’s needs, life history strategies and the varying local environment. This environment is increasingly disturbed as human activity encroaches on previously unexposed regions. This disturbance can have different effects on individual animals or populations depending on their behavioural strategies. Here, we examine a means of predicting the resilience of individuals or populations to unanticipated disturbances, and we find that resilience that can be estimated from routinely collected behavioural observations is a good predictor of how rapidly an individual’s expected behaviour is returned to following a perturbation, and correlates strongly with how much population abundance changes following a disturbance.
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Affiliation(s)
- Stuart Nattrass
- University of Aberdeen, Institute of Biological and Environmental Sciences, Aberdeen AB24 2TZ, UK
| | - David Lusseau
- University of Aberdeen, Institute of Biological and Environmental Sciences, Aberdeen AB24 2TZ, UK
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28
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Manlik O, McDonald JA, Mann J, Raudino HC, Bejder L, Krützen M, Connor RC, Heithaus MR, Lacy RC, Sherwin WB. The relative importance of reproduction and survival for the conservation of two dolphin populations. Ecol Evol 2016; 6:3496-3512. [PMID: 28725349 PMCID: PMC5513288 DOI: 10.1002/ece3.2130] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Revised: 03/19/2016] [Accepted: 03/21/2016] [Indexed: 11/23/2022] Open
Abstract
It has been proposed that in slow‐growing vertebrate populations survival generally has a greater influence on population growth than reproduction. Despite many studies cautioning against such generalizations for conservation, wildlife management for slow‐growing populations still often focuses on perturbing survival without careful evaluation as to whether those changes are likely or feasible. Here, we evaluate the relative importance of reproduction and survival for the conservation of two bottlenose dolphin (Tursiops cf aduncus) populations: a large, apparently stable population and a smaller one that is forecast to decline. We also assessed the feasibility and effectiveness of wildlife management objectives aimed at boosting either reproduction or survival. Consistent with other analytically based elasticity studies, survival had the greatest effect on population trajectories when altering vital rates by equal proportions. However, the findings of our alternative analytical approaches are in stark contrast to commonly used proportional sensitivity analyses and suggest that reproduction is considerably more important. We show that in the stable population reproductive output is higher, and adult survival is lower; the difference in viability between the two populations is due to the difference in reproduction; reproductive rates are variable, whereas survival rates are relatively constant over time; perturbations on the basis of observed, temporal variation indicate that population dynamics are much more influenced by reproduction than by adult survival; for the apparently declining population, raising reproductive rates would be an effective and feasible tool to reverse the forecast population decline; increasing survival would be ineffective.
Our findings highlight the importance of reproduction – even in slow‐growing populations – and the need to assess the effect of natural variation in vital rates on population viability. We echo others in cautioning against generalizations based on life‐history traits and recommend that population modeling for conservation should also take into account the magnitude of vital rate changes that could be attained under alternative management scenarios.
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Affiliation(s)
- Oliver Manlik
- Evolution and Ecology Research Centre School of Biological, Earth and Environmental Sciences University of New South Wales Sydney New South Wales 2052 Australia
| | - Jane A McDonald
- Evolution and Ecology Research Centre School of Biological, Earth and Environmental Sciences University of New South Wales Sydney New South Wales 2052 Australia.,Present address: School of Biological Sciences University of Queensland St Lucia Queensland 4067 Australia
| | - Janet Mann
- Evolution and Ecology Research Centre School of Biological, Earth and Environmental Sciences University of New South Wales Sydney New South Wales 2052 Australia.,Department of Biology and Psychology Georgetown University 37th and O St. NW Washington DC 20057
| | - Holly C Raudino
- Cetacean Research Unit School of Veterinary and Life Sciences Murdoch University South Street Murdoch Western Australia 6150 Australia.,Marine Science Program Department of Parks and Wildlife 17 Dick Perry Avenue. Perth Western Australia 6151 Australia
| | - Lars Bejder
- Cetacean Research Unit School of Veterinary and Life Sciences Murdoch University South Street Murdoch Western Australia 6150 Australia
| | - Michael Krützen
- Evolution and Ecology Research Centre School of Biological, Earth and Environmental Sciences University of New South Wales Sydney New South Wales 2052 Australia.,Anthropological Institute and Museum University of Zurich Winterthurerstrasse 1908057 Zurich Switzerland
| | - Richard C Connor
- Evolution and Ecology Research Centre School of Biological, Earth and Environmental Sciences University of New South Wales Sydney New South Wales 2052 Australia.,Biology Department UMASS-Dartmouth Dartmouth Massachusetts 02747
| | - Michael R Heithaus
- Department of Biological Science School of Environment Arts and Society Florida International University North Miami Florida 33181
| | - Robert C Lacy
- Chicago Zoological Society Brookfield Illinois 60513
| | - William B Sherwin
- Evolution and Ecology Research Centre School of Biological, Earth and Environmental Sciences University of New South Wales Sydney New South Wales 2052 Australia.,Cetacean Research Unit School of Veterinary and Life Sciences Murdoch University South Street Murdoch Western Australia 6150 Australia
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29
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Harwood J, King S, Booth C, Donovan C, Schick RS, Thomas L, New L. Understanding the Population Consequences of Acoustic Disturbance for Marine Mammals. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 875:417-23. [DOI: 10.1007/978-1-4939-2981-8_49] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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30
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Soundscape and Noise Exposure Monitoring in a Marine Protected Area Using Shipping Data and Time-Lapse Footage. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 875:705-12. [PMID: 26611022 DOI: 10.1007/978-1-4939-2981-8_85] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We review recent work that developed new techniques for underwater noise assessment that integrate acoustic monitoring with automatic identification system (AIS) shipping data and time-lapse video, meteorological, and tidal data. Two sites were studied within the Moray Firth Special Area of Conservation (SAC) for bottlenose dolphins, where increased shipping traffic is expected from construction of offshore wind farms outside the SAC. Noise exposure varied markedly between the sites, and natural and anthropogenic contributions were characterized using multiple data sources. At one site, AIS-operating vessels accounted for total cumulative sound exposure (0.1-10 kHz), suggesting that noise modeling using the AIS would be feasible.
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31
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Pirotta E, Harwood J, Thompson PM, New L, Cheney B, Arso M, Hammond PS, Donovan C, Lusseau D. Predicting the effects of human developments on individual dolphins to understand potential long-term population consequences. Proc Biol Sci 2015; 282:20152109. [PMID: 26511044 PMCID: PMC4650163 DOI: 10.1098/rspb.2015.2109] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 09/28/2015] [Indexed: 11/12/2022] Open
Abstract
Human activities that impact wildlife do not necessarily remove individuals from populations. They may also change individual behaviour in ways that have sublethal effects. This has driven interest in developing analytical tools that predict the population consequences of short-term behavioural responses. In this study, we incorporate empirical information on the ecology of a population of bottlenose dolphins into an individual-based model that predicts how individuals' behavioural dynamics arise from their underlying motivational states, as well as their interaction with boat traffic and dredging activities. We simulate the potential effects of proposed coastal developments on this population and predict that the operational phase may affect animals' motivational states. For such results to be relevant for management, the effects on individuals' vital rates also need to be quantified. We investigate whether the relationship between an individual's exposure and the survival of its calves can be directly estimated using a Bayesian multi-stage model for calf survival. The results suggest that any effect on calf survival is probably small and that a significant relationship could only be detected in large, closely studied populations. Our work can be used to guide management decisions, accelerate the consenting process for coastal and offshore developments and design targeted monitoring.
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Affiliation(s)
- Enrico Pirotta
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK
| | - John Harwood
- Scottish Oceans Institute, East Sands, University of St Andrews, St Andrews KY16 8LB, UK Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews KY16 9LZ, UK
| | - Paul M Thompson
- Lighthouse Field Station, Institute of Biological and Environmental Sciences, University of Aberdeen, Cromarty IV11 8YL, UK
| | - Leslie New
- Washington State University, 14204 Salmon Creek Avenue, Vancouver, WA 98686, USA
| | - Barbara Cheney
- Lighthouse Field Station, Institute of Biological and Environmental Sciences, University of Aberdeen, Cromarty IV11 8YL, UK
| | - Monica Arso
- Scottish Oceans Institute, East Sands, University of St Andrews, St Andrews KY16 8LB, UK
| | - Philip S Hammond
- Scottish Oceans Institute, East Sands, University of St Andrews, St Andrews KY16 8LB, UK
| | - Carl Donovan
- Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews KY16 9LZ, UK
| | - David Lusseau
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK
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32
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Collins T. Re-assessment of the Conservation Status of the Atlantic Humpback Dolphin, Sousa teuszii (), Using the IUCN Red List Criteria. ADVANCES IN MARINE BIOLOGY 2015; 72:47-77. [PMID: 26555622 DOI: 10.1016/bs.amb.2015.09.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The Atlantic humpback dolphin (Sousa teuszii) is an obligate shallow water dolphin that is endemic to the western coasts of Africa, ranging from Western Sahara to Angola. The species occurs exclusively in a limited number of near-shore habitats, a tendency that routinely exposes it to a suite of lethal and deleterious anthropogenic threats. These include habitat degradation, accidental capture in artisanal fishing nets, and hunting for use as food and bait. The species also competes with rapidly expanding human populations for coastal resources in some of the poorest countries on Earth. Data for most aspects of the species' ecology are sparse, but S. teuszii is considered by most qualified observers to be rare and greatly threatened. A lack of appropriate survey data precludes a quantitative assessment of population trends and status. Most populations for which any data are available are considered to be extremely small, numbering in the tens or low hundreds of individuals. The available published estimates suggest that the total population likely falls below 3000 individuals. Declines in abundance have been observed or are suspected for each population and will continue, given projected expansions of identified threats that affect most of the species' known range, and a corresponding lack of appropriate management actions. The apparent scale of threats, the presumed isolation of most populations, and a lack of directed conservation efforts in most areas suggest that the species qualifies for a listing of Critically Endangered (under criteria A3cd) on the IUCN Red List.
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Affiliation(s)
- Tim Collins
- Wildlife Conservation Society, Marine Program, Global Conservation, Bronx, New York, USA.
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33
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Maresh JL, Adachi T, Takahashi A, Naito Y, Crocker DE, Horning M, Williams TM, Costa DP. Summing the strokes: energy economy in northern elephant seals during large-scale foraging migrations. MOVEMENT ECOLOGY 2015; 3:22. [PMID: 26380090 PMCID: PMC4570705 DOI: 10.1186/s40462-015-0049-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 08/26/2015] [Indexed: 06/01/2023]
Abstract
BACKGROUND The energy requirements of free-ranging marine mammals are challenging to measure due to cryptic and far-ranging feeding habits, but are important to quantify given the potential impacts of high-level predators on ecosystems. Given their large body size and carnivorous lifestyle, we would predict that northern elephant seals (Mirounga angustirostris) have elevated field metabolic rates (FMRs) that require high prey intake rates, especially during pregnancy. Disturbance associated with climate change or human activity is predicted to further elevate energy requirements due to an increase in locomotor costs required to accommodate a reduction in prey or time available to forage. In this study, we determined the FMRs, total energy requirements, and energy budgets of adult, female northern elephant seals. We also examined the impact of increased locomotor costs on foraging success in this species. RESULTS Body size, time spent at sea and reproductive status strongly influenced FMR. During the short foraging migration, FMR averaged 90.1 (SE = 1.7) kJ kg(-1)d(-1) - only 36 % greater than predicted basal metabolic rate. During the long migration, when seals were pregnant, FMRs averaged 69.4 (±3.0) kJ kg(-1)d(-1) - values approaching those predicted to be necessary to support basal metabolism in mammals of this size. Low FMRs in pregnant seals were driven by hypometabolism coupled with a positive feedback loop between improving body condition and reduced flipper stroking frequency. In contrast, three additional seals carrying large, non-streamlined instrumentation saw a four-fold increase in energy partitioned toward locomotion, resulting in elevated FMRs and only half the mass gain of normally-swimming study animals. CONCLUSIONS These results highlight the importance of keeping locomotion costs low for successful foraging in this species. In preparation for lactation and two fasting periods with high demands on energy reserves, migrating elephant seals utilize an economical foraging strategy whereby energy savings from reduced locomotion costs are shuttled towards somatic growth and fetal gestation. Remarkably, the energy requirements of this species, particularly during pregnancy, are 70-80 % lower than expected for mammalian carnivores, approaching or even falling below values predicted to be necessary to support basal metabolism in mammals of this size.
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Affiliation(s)
- JL Maresh
- />University of California Center for Ocean Health/Long Marine Lab, 100 Shaffer Rd., Santa Cruz, CA 95060 USA
| | - T. Adachi
- />Department of Polar Science, Graduate University for Advanced Studies, Midoricho Tachikawa, Japan
| | - A. Takahashi
- />Department of Polar Science, Graduate University for Advanced Studies, Midoricho Tachikawa, Japan
- />National Institute of Polar Research, Midoricho Tachikawa, Japan
| | - Y. Naito
- />National Institute of Polar Research, Midoricho Tachikawa, Japan
| | - DE Crocker
- />Department of Biology, Sonoma State University, Rohnert Park, USA
| | - M. Horning
- />Department of Fisheries & Wildlife, Marine Mammal Institute, Oregon State University, Newport, USA
| | - TM Williams
- />Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, USA
| | - DP Costa
- />Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, USA
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Wensveen PJ, von Benda-Beckmann AM, Ainslie MA, Lam FPA, Kvadsheim PH, Tyack PL, Miller PJO. How effectively do horizontal and vertical response strategies of long-finned pilot whales reduce sound exposure from naval sonar? MARINE ENVIRONMENTAL RESEARCH 2015; 106:68-81. [PMID: 25795075 DOI: 10.1016/j.marenvres.2015.02.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Revised: 02/16/2015] [Accepted: 02/23/2015] [Indexed: 05/23/2023]
Abstract
The behaviour of a marine mammal near a noise source can modulate the sound exposure it receives. We demonstrate that two long-finned pilot whales both surfaced in synchrony with consecutive arrivals of multiple sonar pulses. We then assess the effect of surfacing and other behavioural response strategies on the received cumulative sound exposure levels and maximum sound pressure levels (SPLs) by modelling realistic spatiotemporal interactions of a pilot whale with an approaching source. Under the propagation conditions of our model, some response strategies observed in the wild were effective in reducing received levels (e.g. movement perpendicular to the source's line of approach), but others were not (e.g. switching from deep to shallow diving; synchronous surfacing after maximum SPLs). Our study exemplifies how simulations of source-whale interactions guided by detailed observational data can improve our understanding about motivations behind behaviour responses observed in the wild (e.g., reducing sound exposure, prey movement).
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Affiliation(s)
- Paul J Wensveen
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB, United Kingdom; Acoustics & Sonar Research Group, Netherlands Organisation for Applied Scientific Research (TNO), PO Box 96864, The Hague, 2509 JG, The Netherlands.
| | - Alexander M von Benda-Beckmann
- Acoustics & Sonar Research Group, Netherlands Organisation for Applied Scientific Research (TNO), PO Box 96864, The Hague, 2509 JG, The Netherlands
| | - Michael A Ainslie
- Acoustics & Sonar Research Group, Netherlands Organisation for Applied Scientific Research (TNO), PO Box 96864, The Hague, 2509 JG, The Netherlands
| | - Frans-Peter A Lam
- Acoustics & Sonar Research Group, Netherlands Organisation for Applied Scientific Research (TNO), PO Box 96864, The Hague, 2509 JG, The Netherlands
| | - Petter H Kvadsheim
- Maritime Systems, Norwegian Defence Research Establishment (FFI), NO-3191, Horten, Norway
| | - Peter L Tyack
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB, United Kingdom
| | - Patrick J O Miller
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY16 8LB, United Kingdom
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35
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Schofield G, Scott R, Katselidis KA, Mazaris AD, Hays GC. Quantifying wildlife-watching ecotourism intensity on an endangered marine vertebrate. Anim Conserv 2015. [DOI: 10.1111/acv.12202] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- G. Schofield
- Centre for Integrative Ecology; School of Life and Environmental Sciences; Deakin University; Warrnambool Vic. Australia
| | - R. Scott
- The Future Ocean Cluster of Excellence; GEOMAR-Helmholtz Centre for Ocean Research; Kiel Germany
| | - K. A. Katselidis
- Department of Environmental and Natural Resources Management; University of Patras; Agrinio Greece
- National Marine Park of Zakynthos; Zakynthos Greece
| | - A. D. Mazaris
- Department of Ecology, School of Biology; Aristotle University of Thessaloniki; Thessaloniki Greece
| | - G. C. Hays
- Centre for Integrative Ecology; School of Life and Environmental Sciences; Deakin University; Warrnambool Vic. Australia
- Department of Biosciences; Swansea University; Swansea UK
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36
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Pirotta E, Brookes KL, Graham IM, Thompson PM. Variation in harbour porpoise activity in response to seismic survey noise. Biol Lett 2014; 10:20131090. [PMID: 24850891 DOI: 10.1098/rsbl.2013.1090] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Animals exposed to anthropogenic disturbance make trade-offs between perceived risk and the cost of leaving disturbed areas. Impact assessments tend to focus on overt behavioural responses leading to displacement, but trade-offs may also impact individual energy budgets through reduced foraging performance. Previous studies found no evidence for broad-scale displacement of harbour porpoises exposed to impulse noise from a 10 day two-dimensional seismic survey. Here, we used an array of passive acoustic loggers coupled with calibrated noise measurements to test whether the seismic survey influenced the activity patterns of porpoises remaining in the area. We showed that the probability of recording a buzz declined by 15% in the ensonified area and was positively related to distance from the source vessel. We also estimated received levels at the hydrophones and characterized the noise response curve. Our results demonstrate how environmental impact assessments can be developed to assess more subtle effects of noise disturbance on activity patterns and foraging efficiency.
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Affiliation(s)
- Enrico Pirotta
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK
| | - Kate L Brookes
- Lighthouse Field Station, Institute of Biological and Environmental Sciences, University of Aberdeen, Cromarty IV11 8YL, UK Marine Scotland Science, Marine Laboratory, Aberdeen AB11 9DB, UK
| | - Isla M Graham
- Lighthouse Field Station, Institute of Biological and Environmental Sciences, University of Aberdeen, Cromarty IV11 8YL, UK
| | - Paul M Thompson
- Lighthouse Field Station, Institute of Biological and Environmental Sciences, University of Aberdeen, Cromarty IV11 8YL, UK
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37
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Activities, motivations and disturbance: An agent-based model of bottlenose dolphin behavioral dynamics and interactions with tourism in Doubtful Sound, New Zealand. Ecol Modell 2014. [DOI: 10.1016/j.ecolmodel.2014.03.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Pirotta E, Thompson PM, Cheney B, Donovan CR, Lusseau D. Estimating spatial, temporal and individual variability in dolphin cumulative exposure to boat traffic using spatially explicit capture-recapture methods. Anim Conserv 2014. [DOI: 10.1111/acv.12132] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- E. Pirotta
- Institute of Biological and Environmental Sciences; University of Aberdeen; Aberdeen UK
| | - P. M. Thompson
- Lighthouse Field Station; Institute of Biological and Environmental Sciences; University of Aberdeen; Cromarty UK
| | - B. Cheney
- Lighthouse Field Station; Institute of Biological and Environmental Sciences; University of Aberdeen; Cromarty UK
| | - C. R. Donovan
- Centre for Research into Ecological and Environmental Modelling; University of St Andrews; St Andrews UK
| | - D. Lusseau
- Institute of Biological and Environmental Sciences; University of Aberdeen; Aberdeen UK
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39
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May-Collado LJ, Quiñones-Lebrón SG. Dolphin changes in whistle structure with watercraft activity depends on their behavioral state. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2014; 135:EL193-EL198. [PMID: 25236153 DOI: 10.1121/1.4869255] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Dolphins rely on whistles to identify each other and to receive and convey information about their environment. Although capable of adjusting these signals with changing environments, there is little information on how dolphins acoustically respond to different watercraft activities and if this response depends on dolphin behavioral state. Bottlenose dolphin whistles were recorded in the presence of research and dolphin-watching boats. Dolphins emitted lower frequency and longer whistles when interacting with dolphin-watching boats, particularly during foraging activities. This study suggests that dolphin-watching boat traffic significantly hinders dolphin communication during important behavioral states.
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Affiliation(s)
- Laura J May-Collado
- Department of Biology, University of Vermont, 109 Carrigan Drive, Burlington, Vermont 05405
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40
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Merchant ND, Pirotta E, Barton TR, Thompson PM. Monitoring ship noise to assess the impact of coastal developments on marine mammals. MARINE POLLUTION BULLETIN 2014; 78:85-95. [PMID: 24279956 DOI: 10.1016/j.marpolbul.2013.10.058] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 10/29/2013] [Accepted: 10/31/2013] [Indexed: 06/02/2023]
Abstract
The potential impacts of underwater noise on marine mammals are widely recognised, but uncertainty over variability in baseline noise levels often constrains efforts to manage these impacts. This paper characterises natural and anthropogenic contributors to underwater noise at two sites in the Moray Firth Special Area of Conservation, an important marine mammal habitat that may be exposed to increased shipping activity from proposed offshore energy developments. We aimed to establish a pre-development baseline, and to develop ship noise monitoring methods using Automatic Identification System (AIS) and time-lapse video to record trends in noise levels and shipping activity. Our results detail the noise levels currently experienced by a locally protected bottlenose dolphin population, explore the relationship between broadband sound exposure levels and the indicators proposed in response to the EU Marine Strategy Framework Directive, and provide a ship noise assessment toolkit which can be applied in other coastal marine environments.
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Affiliation(s)
| | - Enrico Pirotta
- University of Aberdeen, Institute of Biological & Environmental Sciences, Lighthouse Field Station, Cromarty, Ross-shire IV11 8YL, UK
| | - Tim R Barton
- University of Aberdeen, Institute of Biological & Environmental Sciences, Lighthouse Field Station, Cromarty, Ross-shire IV11 8YL, UK
| | - Paul M Thompson
- University of Aberdeen, Institute of Biological & Environmental Sciences, Lighthouse Field Station, Cromarty, Ross-shire IV11 8YL, UK
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41
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Bailey H, Brookes KL, Thompson PM. Assessing environmental impacts of offshore wind farms: lessons learned and recommendations for the future. AQUATIC BIOSYSTEMS 2014; 10:8. [PMID: 25250175 PMCID: PMC4172316 DOI: 10.1186/2046-9063-10-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 09/03/2014] [Indexed: 05/06/2023]
Abstract
Offshore wind power provides a valuable source of renewable energy that can help reduce carbon emissions. Technological advances are allowing higher capacity turbines to be installed and in deeper water, but there is still much that is unknown about the effects on the environment. Here we describe the lessons learned based on the recent literature and our experience with assessing impacts of offshore wind developments on marine mammals and seabirds, and make recommendations for future monitoring and assessment as interest in offshore wind energy grows around the world. The four key lessons learned that we discuss are: 1) Identifying the area over which biological effects may occur to inform baseline data collection and determining the connectivity between key populations and proposed wind energy sites, 2) The need to put impacts into a population level context to determine whether they are biologically significant, 3) Measuring responses to wind farm construction and operation to determine disturbance effects and avoidance responses, and 4) Learn from other industries to inform risk assessments and the effectiveness of mitigation measures. As the number and size of offshore wind developments increases, there will be a growing need to consider the population level consequences and cumulative impacts of these activities on marine species. Strategically targeted data collection and modeling aimed at answering questions for the consenting process will also allow regulators to make decisions based on the best available information, and achieve a balance between climate change targets and environmental legislation.
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Affiliation(s)
- Helen Bailey
- Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, 146 Williams Street, Solomons, MD 20688, USA
| | - Kate L Brookes
- Marine Scotland Science, 375 Victoria Road, Aberdeen AB11 9DB, UK
| | - Paul M Thompson
- Institute of Biological and Environmental Sciences, Lighthouse Field Station, University of Aberdeen, George Street, Cromarty, Ross-shire IV11 8YJ, UK
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42
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Palacios DM, Baumgartner MF, Laidre KL, Gregr EJ. Beyond correlation: integrating environmentally and behaviourally mediated processes in models of marine mammal distributions. ENDANGER SPECIES RES 2013. [DOI: 10.3354/esr00558] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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43
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Thompson PM, Brookes KL, Graham IM, Barton TR, Needham K, Bradbury G, Merchant ND. Short-term disturbance by a commercial two-dimensional seismic survey does not lead to long-term displacement of harbour porpoises. Proc Biol Sci 2013; 280:20132001. [PMID: 24089338 PMCID: PMC3790491 DOI: 10.1098/rspb.2013.2001] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 09/11/2013] [Indexed: 11/12/2022] Open
Abstract
Assessments of the impact of offshore energy developments are constrained because it is not known whether fine-scale behavioural responses to noise lead to broader-scale displacement of protected small cetaceans. We used passive acoustic monitoring and digital aerial surveys to study changes in the occurrence of harbour porpoises across a 2000 km(2) study area during a commercial two-dimensional seismic survey in the North Sea. Acoustic and visual data provided evidence of group responses to airgun noise from the 470 cu inch array over ranges of 5-10 km, at received peak-to-peak sound pressure levels of 165-172 dB re 1 µPa and sound exposure levels (SELs) of 145-151 dB re 1 µPa(2) s(-1). However, animals were typically detected again at affected sites within a few hours, and the level of response declined through the 10 day survey. Overall, acoustic detections decreased significantly during the survey period in the impact area compared with a control area, but this effect was small in relation to natural variation. These results demonstrate that prolonged seismic survey noise did not lead to broader-scale displacement into suboptimal or higher-risk habitats, and suggest that impact assessments should focus on sublethal effects resulting from changes in foraging performance of animals within affected sites.
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Affiliation(s)
- Paul M. Thompson
- Lighthouse Field Station, Institute of Biological and Environmental Sciences, University of Aberdeen, Cromarty IV 11 8YL, UK
| | - Kate L. Brookes
- Lighthouse Field Station, Institute of Biological and Environmental Sciences, University of Aberdeen, Cromarty IV 11 8YL, UK
| | - Isla M. Graham
- Lighthouse Field Station, Institute of Biological and Environmental Sciences, University of Aberdeen, Cromarty IV 11 8YL, UK
| | - Tim R. Barton
- Lighthouse Field Station, Institute of Biological and Environmental Sciences, University of Aberdeen, Cromarty IV 11 8YL, UK
| | - Keith Needham
- Kongsberg Maritime Ltd, 11 The Briars, Waterberry Drive, Waterlooville, Hampshire PO7 7YH, UK
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44
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Christiansen F, Rasmussen MH, Lusseau D. Inferring activity budgets in wild animals to estimate the consequences of disturbances. Behav Ecol 2013. [DOI: 10.1093/beheco/art086] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Fredrik Christiansen
- Institute of Biological and Environmental Sciences, University of Aberdeen, Zoology Building, Tillydrone Avenue, AB24 2TZ Aberdeen, UK,
| | - Marianne H. Rasmussen
- Húsavik Research Center, University of Iceland, Hafnarstett 3, 640 Húsavik, Iceland, and
| | - David Lusseau
- Institute of Biological and Environmental Sciences, University of Aberdeen, Zoology Building, Tillydrone Avenue, AB24 2TZ Aberdeen, UK,
- Marine Alliance for Science and Technology for Scotland, University of Aberdeen, Zoology Building, Tillydrone Avenue, AB24 2TZ Aberdeen, UK
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45
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Pirotta E, Laesser BE, Hardaker A, Riddoch N, Marcoux M, Lusseau D. Dredging displaces bottlenose dolphins from an urbanised foraging patch. MARINE POLLUTION BULLETIN 2013; 74:396-402. [PMID: 23816305 DOI: 10.1016/j.marpolbul.2013.06.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 06/06/2013] [Accepted: 06/08/2013] [Indexed: 06/02/2023]
Abstract
The exponential growth of the human population and its increasing industrial development often involve large scale modifications of the environment. In the marine context, coastal urbanisation and harbour expansion to accommodate the rising levels of shipping and offshore energy exploitation require dredging to modify the shoreline and sea floor. While the consequences of dredging on invertebrates and fish are relatively well documented, no study has robustly tested the effects on large marine vertebrates. We monitored the attendance of common bottlenose dolphins (Tursiops truncatus) to a recently established urbanised foraging patch, Aberdeen harbour (Scotland), and modelled the effect of dredging operations on site usage. We found that higher intensities of dredging caused the dolphins to spend less time in the harbour, despite high baseline levels of disturbance and the importance of the area as a foraging patch.
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Affiliation(s)
- Enrico Pirotta
- Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK.
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46
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Pirotta E, Thompson PM, Miller PI, Brookes KL, Cheney B, Barton TR, Graham IM, Lusseau D. Scale-dependent foraging ecology of a marine top predator modelled using passive acoustic data. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12146] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Enrico Pirotta
- Institute of Biological and Environmental Sciences; University of Aberdeen; Aberdeen AB24 2TZ, UK
| | - Paul M. Thompson
- Lighthouse Field Station; Institute of Biological and Environmental Sciences; University of Aberdeen; Cromarty IV11 8YL, UK
| | | | - Kate L. Brookes
- Lighthouse Field Station; Institute of Biological and Environmental Sciences; University of Aberdeen; Cromarty IV11 8YL, UK
| | - Barbara Cheney
- Lighthouse Field Station; Institute of Biological and Environmental Sciences; University of Aberdeen; Cromarty IV11 8YL, UK
| | - Tim R. Barton
- Lighthouse Field Station; Institute of Biological and Environmental Sciences; University of Aberdeen; Cromarty IV11 8YL, UK
| | - Isla M. Graham
- Lighthouse Field Station; Institute of Biological and Environmental Sciences; University of Aberdeen; Cromarty IV11 8YL, UK
| | - David Lusseau
- Institute of Biological and Environmental Sciences; University of Aberdeen; Aberdeen AB24 2TZ, UK
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