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Rider MJ, Kirsebom OS, Gallagher AJ, Staaterman E, Ault JS, Sasso CR, Jackson T, Browder JA, Hammerschlag N. Space use patterns of sharks in relation to boat activity in an urbanized coastal waterway. Mar Environ Res 2021; 172:105489. [PMID: 34619503 DOI: 10.1016/j.marenvres.2021.105489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 09/24/2021] [Accepted: 09/26/2021] [Indexed: 06/13/2023]
Abstract
Aquatic ecosystems face numerous anthropogenic threats associated with coastal urbanization, with boat activity being among the most prevalent. The present study aimed to evaluate a potential relationship between boat activity and shark space use in Biscayne Bay, Florida (USA), a coastal waterway exposed to high levels of boating. Spatiotemporal patterns in boat density and traffic were determined from aerial surveys and underwater acoustic recorders, respectively. These data were then compared with residency patterns of bull (Carcharhinus leucas), nurse (Ginglymostoma cirratum) and great hammerhead (Sphyrna mokarran) sharks quantified through passive acoustic telemetry. Results were mixed, with no detectable relationship between boat density and shark residency for any of the species. Hourly presence of G. cirratum decreased with increasing boat traffic, a relationship not seen in the other two species. Explanations for these results include habituation of sharks to the high levels of chronic boat activity in the study area and interspecific differences in hearing sensitivity.
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Affiliation(s)
- Mitchell J Rider
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA.
| | - Oliver S Kirsebom
- Institute for Big Data Analytics, Dalhousie University, 6299 South St, Halifax, Nova Scotia, B3H 4R2, Canada
| | | | | | - Jerald S Ault
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
| | - Christopher R Sasso
- National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Science Center, 75 Virginia Beach Dr, Miami, FL, 33149, USA
| | - Tom Jackson
- National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Science Center, 75 Virginia Beach Dr, Miami, FL, 33149, USA
| | - Joan A Browder
- National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Science Center, 75 Virginia Beach Dr, Miami, FL, 33149, USA
| | - Neil Hammerschlag
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA; Leonard & Jayne Abess Center for Ecosystem Science and Policy, University of Miami, 1365 Memorial Dr, Coral Gables, Florida, 33146, USA
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Bradley P, Jessup B, Pittman SJ, Jeffrey CFG, Ault JS, Carrubba L, Lilyestrom C, Appeldoorn RS, Schärer MT, Walker BK, McField M, Santavy DL, Smith TB, García-Moliner G, Smith SG, Huertas E, Gerritsen J, Oliver LM, Horstmann C, Jackson SK. Development of a reef fish biological condition gradient model with quantitative decision rules for the protection and restoration of coral reef ecosystems. Mar Pollut Bull 2020; 159:111387. [PMID: 32827871 PMCID: PMC8717739 DOI: 10.1016/j.marpolbul.2020.111387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 06/11/2020] [Accepted: 06/16/2020] [Indexed: 05/09/2023]
Abstract
Coral reef ecosystems are declining due to multiple interacting stressors. A bioassessment framework focused on stressor-response associations was developed to help organize and communicate complex ecological information to support coral reef conservation. This study applied the Biological Condition Gradient (BCG), initially developed for freshwater ecosystems, to fish assemblages of U.S. Caribbean coral reef ecosystems. The reef fish BCG describes how biological conditions changed incrementally along a gradient of increasing anthropogenic stress. Coupled with physical and chemical water quality data, the BGC forms a scientifically defensible basis to prioritize, protect and restore water bodies containing coral reefs. Through an iterative process, scientists from across the U.S. Caribbean used fishery-independent survey data and expert knowledge to develop quantitative decision rules to describe six levels of coral reef ecosystem condition. The resultant reef fish BCG provides an effective tool for identifying healthy and degraded coral reef ecosystems and has potential for global application.
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Affiliation(s)
| | | | | | - Christopher F G Jeffrey
- CSS-Inc., Fairfax, VA, USA; Under Contract to NOAA, National Centers for Coastal Ocean Science, Marine Spatial Ecology Division, Biogeography Branch, Silver Spring, MD, USA
| | - Jerald S Ault
- University of Miami, Rosenstiel School of Marine and Atmospheric Science, Miami, FL, USA
| | | | - Craig Lilyestrom
- Puerto Rico Department of Natural and Environmental Resources, San Juan, PR, USA
| | | | | | - Brian K Walker
- Nova Southeastern University, Halmos College of Natural Sciences and Oceanography, Fort Lauderdale, FL, USA
| | | | - Deborah L Santavy
- U.S. Environmental Protection Agency (US EPA), Office of Research and Development (ORD), Center for Environmental, Measurement and Modeling (CEMM), Gulf Ecosystem Measurement and Modeling Division (GEMMD), Gulf Breeze, FL, USA.
| | - Tyler B Smith
- University of the Virgin Islands, St. Thomas, VI, USA
| | | | - Steven G Smith
- University of Miami, Rosenstiel School of Marine and Atmospheric Science, Miami, FL, USA
| | - Evelyn Huertas
- U.S. Environmental Protection Agency, Region 2, Guaynabo, PR, USA
| | | | - Leah M Oliver
- U.S. Environmental Protection Agency (US EPA), Office of Research and Development (ORD), Center for Environmental, Measurement and Modeling (CEMM), Gulf Ecosystem Measurement and Modeling Division (GEMMD), Gulf Breeze, FL, USA
| | - Christina Horstmann
- U.S. Environmental Protection Agency (US EPA), Office of Research and Development (ORD), Center for Environmental, Measurement and Modeling (CEMM), Gulf Ecosystem Measurement and Modeling Division (GEMMD), Gulf Breeze, FL, USA; Oak Ridge Institute for Science Education Fellow, US EPA, ORD, CEMM, GEMMD, Gulf Breeze, FL, USA
| | - Susan K Jackson
- U.S. Environmental Protection Agency, Office of Water, Washington, DC, USA
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Bryan DR, Blondeau J, Siana A, Ault JS. Regional differences in an established population of invasive Indo-Pacific lionfish ( Pterois volitans and P. miles) in south Florida. PeerJ 2018; 6:e5700. [PMID: 30324014 PMCID: PMC6186158 DOI: 10.7717/peerj.5700] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 09/06/2018] [Indexed: 11/20/2022] Open
Abstract
About nine years ago (circa 2009), Indo-Pacific lionfishes (Pterois volitans and P. miles) invaded the south Florida coral reef ecosystem. During the intervening period of time, there has been substantial research on their biology, life history, demography, and habitat preferences; however, little is known concerning their regional population status and trends in the region. Here, we use a large-scale fisheries independent reef fish visual survey to investigate lionfish population status among three south Florida regions: Dry Tortugas, Florida Keys, and southeast Florida. Density estimates (ind ha−1) have been relatively stable since 2012, and are lower than other areas reported in the western Atlantic and Caribbean Sea. Low, stable population densities in south Florida suggest there may be a natural mechanism for lionfish population control. In the Dry Tortugas, lionfish density in 2016 was significantly lower (0.6 ind ha−1 ± 0.15 SE) than the two other south Florida regions. The Dry Tortugas region has the highest percentage of marine protected areas, the lowest level of exploitation, and thus the highest densities of potential lionfish predators and competitors. In the Florida Keys and southeast Florida in 2016, lionfish densities were greater (5.4 ind ha−1 ± 1.0 SE and 9.0 ± 2.7 SE, respectively) than the Dry Tortugas. Fishing pressure on lionfish was higher in these two regions, but densities of several potential predators and competitors were substantially lower. Despite relatively low regional lionfish densities that can be attributed to some combination of fishing mortality and natural biocontrol, lionfish are still well established in the south Florida coral reef ecosystem, warranting continued concern.
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Affiliation(s)
- David R Bryan
- Department of Marine Ecosystems and Society, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, United States of America.,Pacific States Marine Fisheries Commission, Alaska Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA, United States of America
| | - Jeremiah Blondeau
- Southeast Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Miami, FL, United States of America
| | - Ashley Siana
- Department of Marine Ecosystems and Society, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, United States of America
| | - Jerald S Ault
- Department of Marine Ecosystems and Society, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, United States of America
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Brown CE, Bhat MG, Rehage JS, Mirchi A, Boucek R, Engel V, Ault JS, Mozumder P, Watkins D, Sukop M. Ecological-economic assessment of the effects of freshwater flow in the Florida Everglades on recreational fisheries. Sci Total Environ 2018; 627:480-493. [PMID: 29426171 DOI: 10.1016/j.scitotenv.2018.01.038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 12/14/2017] [Accepted: 01/05/2018] [Indexed: 06/08/2023]
Abstract
This research develops an integrated methodology to determine the economic value to anglers of recreational fishery ecosystem services in Everglades National Park that could result from different water management scenarios. The study first used bio-hydrological models to link managed freshwater inflows to indicators of fishery productivity and ecosystem health, then link those models to anglers' willingness-to-pay for various attributes of the recreational fishing experience and monthly fishing effort. This approach allowed us to estimate the foregone economic benefits of failing to meet monthly freshwater delivery targets. The study found that the managed freshwater delivery to the Park had declined substantially over the years and had fallen short of management targets. This shortage in the flow resulted in the decline of biological productivity of recreational fisheries in downstream coastal areas. This decline had in turn contributed to reductions in the overall economic value of recreational ecosystem services enjoyed by anglers. The study estimated the annual value of lost recreational services at $68.81 million. The losses were greater in the months of dry season when the water shortage was higher and the number of anglers fishing also was higher than the levels in wet season. The study also developed conservative estimates of implicit price of water for recreation, which ranged from $11.88 per AF in November to $112.11 per AF in April. The annual average price was $41.54 per AF. Linking anglers' recreational preference directly to a decision variable such as water delivery is a powerful and effective way to make management decision. This methodology has relevant applications to water resource management, serving as useful decision-support metrics, as well as for policy and restoration scenario analysis.
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Affiliation(s)
| | - Mahadev G Bhat
- Florida International University, Miami, FL, United States.
| | | | - Ali Mirchi
- University of Texas at El Paso, El Paso, TX, United States.
| | - Ross Boucek
- Florida Fish and Wildlife Research Institute, St. Petersburg, FL, United States.
| | - Victor Engel
- U.S. Forest Service, Fort Collins, CO, United States.
| | | | | | - David Watkins
- Michigan Technological University, Houghton, MI, United States.
| | - Michael Sukop
- Florida International University, Miami, FL, United States.
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Graham F, Rynne P, Estevanez M, Luo J, Ault JS, Hammerschlag N. Front Cover. DIVERS DISTRIB 2016. [DOI: 10.1111/ddi.12445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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Graham F, Rynne P, Estevanez M, Luo J, Ault JS, Hammerschlag N. Use of marine protected areas and exclusive economic zones in the subtropical western North Atlantic Ocean by large highly mobile sharks. DIVERS DISTRIB 2016. [DOI: 10.1111/ddi.12425] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Fiona Graham
- Rosenstiel School of Marine and Atmospheric Science; University of Miami; 4600 Rickenbacker Causeway Miami FL 33149 USA
| | - Patrick Rynne
- Rosenstiel School of Marine and Atmospheric Science; University of Miami; 4600 Rickenbacker Causeway Miami FL 33149 USA
| | - Maria Estevanez
- Rosenstiel School of Marine and Atmospheric Science; University of Miami; 4600 Rickenbacker Causeway Miami FL 33149 USA
| | - Jiangang Luo
- Rosenstiel School of Marine and Atmospheric Science; University of Miami; 4600 Rickenbacker Causeway Miami FL 33149 USA
| | - Jerald S. Ault
- Rosenstiel School of Marine and Atmospheric Science; University of Miami; 4600 Rickenbacker Causeway Miami FL 33149 USA
| | - Neil Hammerschlag
- Rosenstiel School of Marine and Atmospheric Science; University of Miami; 4600 Rickenbacker Causeway Miami FL 33149 USA
- Leonard and Jayne Abess Center for Ecosystem Science and Policy; University of Miami; PO Box 248203 Coral Gables FL 33146 USA
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7
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Luo J, Ault JS, Shay LK, Hoolihan JP, Prince ED, Brown CA, Rooker JR. Ocean Heat Content Reveals Secrets of Fish Migrations. PLoS One 2015; 10:e0141101. [PMID: 26484541 PMCID: PMC4617419 DOI: 10.1371/journal.pone.0141101] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 10/05/2015] [Indexed: 11/19/2022] Open
Abstract
For centuries, the mechanisms surrounding spatially complex animal migrations have intrigued scientists and the public. We present a new methodology using ocean heat content (OHC), a habitat metric that is normally a fundamental part of hurricane intensity forecasting, to estimate movements and migration of satellite-tagged marine fishes. Previous satellite-tagging research of fishes using archival depth, temperature and light data for geolocations have been too coarse to resolve detailed ocean habitat utilization. We combined tag data with OHC estimated from ocean circulation and transport models in an optimization framework that substantially improved geolocation accuracy over SST-based tracks. The OHC-based movement track provided the first quantitative evidence that many of the tagged highly migratory fishes displayed affinities for ocean fronts and eddies. The OHC method provides a new quantitative tool for studying dynamic use of ocean habitats, migration processes and responses to environmental changes by fishes, and further, improves ocean animal tracking and extends satellite-based animal tracking data for other potential physical, ecological, and fisheries applications.
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Affiliation(s)
- Jiangang Luo
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida, United States of America
| | - Jerald S. Ault
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida, United States of America
- * E-mail:
| | - Lynn K. Shay
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida, United States of America
| | - John P. Hoolihan
- Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, Florida, United States of America
| | - Eric D. Prince
- Southeast Fisheries Science Center, Sustainable Fisheries Division, Highly Migratory Species Branch, NOAA Fisheries, Miami, Florida, United States of America
| | - Craig A. Brown
- Southeast Fisheries Science Center, Sustainable Fisheries Division, Highly Migratory Species Branch, NOAA Fisheries, Miami, Florida, United States of America
| | - Jay R. Rooker
- Department of Marine Biology, Texas A&M University, Galveston, Texas, United States of America
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Nadon MO, Ault JS, Williams ID, Smith SG, DiNardo GT. Length-based assessment of coral reef fish populations in the main and northwestern Hawaiian islands. PLoS One 2015; 10:e0133960. [PMID: 26267473 PMCID: PMC4534412 DOI: 10.1371/journal.pone.0133960] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Accepted: 07/05/2015] [Indexed: 11/18/2022] Open
Abstract
The coral reef fish community of Hawaii is composed of hundreds of species, supports a multimillion dollar fishing and tourism industry, and is of great cultural importance to the local population. However, a major stock assessment of Hawaiian coral reef fish populations has not yet been conducted. Here we used the robust indicator variable "average length in the exploited phase of the population ([Formula: see text])", estimated from size composition data from commercial fisheries trip reports and fishery-independent diver surveys, to evaluate exploitation rates for 19 Hawaiian reef fishes. By and large, the average lengths obtained from diver surveys agreed well with those from commercial data. We used the estimated exploitation rates coupled with life history parameters synthesized from the literature to parameterize a numerical population model and generate stock sustainability metrics such as spawning potential ratios (SPR). We found good agreement between predicted average lengths in an unfished population (from our population model) and those observed from diver surveys in the largely unexploited Northwestern Hawaiian Islands. Of 19 exploited reef fish species assessed in the main Hawaiian Islands, 9 had SPRs close to or below the 30% overfishing threshold. In general, longer-lived species such as surgeonfishes, the redlip parrotfish (Scarus rubroviolaceus), and the gray snapper (Aprion virescens) had the lowest SPRs, while short-lived species such as goatfishes and jacks, as well as two invasive species (Lutjanus kasmira and Cephalopholis argus), had SPRs above the 30% threshold.
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Affiliation(s)
- Marc O Nadon
- University of Miami, Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Causeway, Miami, FL, 33149, United States of America; Joint Institute for Marine and Atmospheric Research, 1000 Pope Road, Honolulu, HI, 96822 United States of America; NOAA Fisheries, Pacific Islands Fisheries Science Center, 1845 Wasp Boulevard, Honolulu, HI, 96818, United States of America
| | - Jerald S Ault
- University of Miami, Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Causeway, Miami, FL, 33149, United States of America
| | - Ivor D Williams
- NOAA Fisheries, Pacific Islands Fisheries Science Center, 1845 Wasp Boulevard, Honolulu, HI, 96818, United States of America
| | - Steven G Smith
- University of Miami, Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Causeway, Miami, FL, 33149, United States of America
| | - Gerard T DiNardo
- NOAA Fisheries, Pacific Islands Fisheries Science Center, 1845 Wasp Boulevard, Honolulu, HI, 96818, United States of America
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Farmer NA, Ault JS, Smith SG, Franklin EC. Methods for assessment of short-term coral reef fish movements within an acoustic array. Mov Ecol 2013; 1:7. [PMID: 25709821 PMCID: PMC4337750 DOI: 10.1186/2051-3933-1-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Accepted: 06/21/2013] [Indexed: 06/04/2023]
Abstract
BACKGROUND Arrays of passive receivers are a widely used tool for tracking the movements of acoustically-tagged fish in marine ecosystems; however, the spatial and temporal heterogeneity of coral reef environments pose challenges for the interpretation of tag detection data. To improve this situation for reef fishes, we introduced a novel response variable method that treats signal detections as proportions (i.e., percent transmissions detected or "detection rates") and compared this against prior approaches to examine the influence of array and transmitter performance, signal distance and environmental factors on detection rates. We applied this method to tagged snappers and groupers in the Florida reef ecosystem and controlled range-tests on static targets in Bayboro Harbor, Florida, to provide methodological guidance for the planning and evaluation of passive array studies for coral reef fishes. RESULTS Logistic regression analysis indicated detection rates were primarily a non-linear function of tag distance from receiver. A 'model-weighted' function was developed to incorporate the non-linear relationship between detection rate and distance to provide robust positioning estimates and allow for easy extension to tags with different ping rates. CONCLUSIONS Optimal acoustic array design requires balancing the interplay between receiver spacing, detection rates, and positioning error. Spacing receivers at twice the distance of the modeled 50% detection rate may be appropriate when quantification of overall space use is a priority, and would provide a minimum of 75% detection rate. However, for research where missing detections within the array is unacceptable or time-at-arrival based fine-scale positioning is needed, tighter receiver spacing may be required to maintain signal detection probability near 100%.
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Affiliation(s)
- Nicholas A Farmer
- />Division of Marine Biology and Fisheries, University of Miami, Rosenstiel School for Marine and Atmospheric Science, 4600 Rickenbacker Causeway, Miami, FL 33149 USA
- />NOAA Fisheries, Southeast Regional Office, 263 13th Ave South, Saint Petersburg, FL 33701 USA
| | - Jerald S Ault
- />Division of Marine Biology and Fisheries, University of Miami, Rosenstiel School for Marine and Atmospheric Science, 4600 Rickenbacker Causeway, Miami, FL 33149 USA
| | - Steven G Smith
- />Division of Marine Biology and Fisheries, University of Miami, Rosenstiel School for Marine and Atmospheric Science, 4600 Rickenbacker Causeway, Miami, FL 33149 USA
| | - Erik C Franklin
- />School of Ocean and Earth Science and Technology, Hawai’i Institute of Marine Biology, University of Hawai’i at Manoa, PO Box 1346, Kaneohe, HI 96744 USA
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Hammerschlag N, Luo J, Irschick DJ, Ault JS. A comparison of spatial and movement patterns between sympatric predators: bull sharks (Carcharhinus leucas) and Atlantic tarpon (Megalops atlanticus). PLoS One 2012; 7:e45958. [PMID: 23049904 PMCID: PMC3458817 DOI: 10.1371/journal.pone.0045958] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 08/28/2012] [Indexed: 11/30/2022] Open
Abstract
Background Predators can impact ecosystems through trophic cascades such that differential patterns in habitat use can lead to spatiotemporal variation in top down forcing on community dynamics. Thus, improved understanding of predator movements is important for evaluating the potential ecosystem effects of their declines. Methodology/Principal Findings We satellite-tagged an apex predator (bull sharks, Carcharhinus leucas) and a sympatric mesopredator (Atlantic tarpon, Megalops atlanticus) in southern Florida waters to describe their habitat use, abundance and movement patterns. We asked four questions: (1) How do the seasonal abundance patterns of bull sharks and tarpon compare? (2) How do the movement patterns of bull sharks and tarpon compare, and what proportion of time do their respective primary ranges overlap? (3) Do tarpon movement patterns (e.g., straight versus convoluted paths) and/or their rates of movement (ROM) differ in areas of low versus high bull shark abundance? and (4) Can any general conclusions be reached concerning whether tarpon may mitigate risk of predation by sharks when they are in areas of high bull shark abundance? Conclusions/Significance Despite similarities in diet, bull sharks and tarpon showed little overlap in habitat use. Bull shark abundance was high year-round, but peaked in winter; while tarpon abundance and fishery catches were highest in late spring. However, presence of the largest sharks (>230 cm) coincided with peak tarpon abundance. When moving over deep open waters (areas of high shark abundance and high food availability) tarpon maintained relatively high ROM in directed lines until reaching shallow structurally-complex areas. At such locations, tarpon exhibited slow tortuous movements over relatively long time periods indicative of foraging. Tarpon periodically concentrated up rivers, where tracked bull sharks were absent. We propose that tarpon trade-off energetic costs of both food assimilation and osmoregulation to reduce predation risk by bull sharks.
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Affiliation(s)
- Neil Hammerschlag
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida, USA.
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Hammerschlag N, Gallagher AJ, Wester J, Luo J, Ault JS. Don’t bite the hand that feeds: assessing ecological impacts of provisioning ecotourism on an apex marine predator. Funct Ecol 2012. [DOI: 10.1111/j.1365-2435.2012.01973.x] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Meester GA, Ault JS, Smith SG, Mehrotra A. An integrated simulation modeling and operations research approach to spatial management decision making. ACTA ACUST UNITED AC 2012. [DOI: 10.1080/00364827.2001.10420492] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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13
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Smith SG, Swanson DW, Chiappone M, Miller SL, Ault JS. Probability sampling of stony coral populations in the Florida Keys. Environ Monit Assess 2011; 183:121-38. [PMID: 21547375 DOI: 10.1007/s10661-011-1912-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Accepted: 01/27/2011] [Indexed: 05/24/2023]
Abstract
Principles of probability survey design were applied to guide large-scale sampling of populations of stony corals and associated benthic taxa in the Florida Keys coral reef ecosystem. The survey employed a two-stage stratified random sampling design that partitioned the 251-km(2) domain by reef habitat types, geographic regions, and management zones. Estimates of the coefficient of variation (ratio of standard error to the mean) for stony coral population density and abundance ranged from 7% to 12% for four of six principal species. These levels of survey precision are among the highest reported for comparable surveys of marine species. Relatively precise estimates were also obtained for octocoral density, sponge frequency of occurrence, and benthic cover of algae and invertebrates. Probabilistic survey design techniques provided a robust framework for estimating population-level metrics and optimizing sampling efficiency.
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Affiliation(s)
- Steven G Smith
- Rosenstiel School of Marine and Atmospheric Science, Division of Marine Biology and Fisheries, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA.
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Abstract
A unified mechanistic approach is given for the derivation of various forms of functional response in predator-prey models. The derivation is based on the principle of mass action but with the crucial refinement that the nature of the spatial distribution of predators and/or opportunities for predation are taken into account in an implicit way. If the predators are assumed to have a homogeneous spatial distribution, then the derived functional response is prey-dependent. If the predators are assumed to form a dense colony or school in a single (possibly moving) location, or if the region where predators can encounter prey is assumed to be of limited size, then the functional response depends on both predator and prey densities in a manner that reflects feeding interference between predators. Depending on the specific assumptions, the resulting functional response may be of Beddington-DeAngelis type, of Hassell-Varley type, or ratio-dependent.
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Affiliation(s)
- C Cosner
- Department of Mathematics and Computer Science, University of Miami, Coral Gables, Florida, 33124, USA
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