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Valkiūnas G, Iezhova TA. Insights into the Biology of Leucocytozoon Species (Haemosporida, Leucocytozoidae): Why Is There Slow Research Progress on Agents of Leucocytozoonosis? Microorganisms 2023; 11:1251. [PMID: 37317225 DOI: 10.3390/microorganisms11051251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/04/2023] [Accepted: 05/05/2023] [Indexed: 06/16/2023] Open
Abstract
Blood parasites of the genus Leucocytozoon (Leucocytozoidae) only inhabit birds and represent a readily distinct evolutionary branch of the haemosporidians (Haemosporida, Apicomplexa). Some species cause pathology and even severe leucocytozoonosis in avian hosts, including poultry. The diversity of Leucocytozoon pathogens is remarkable, with over 1400 genetic lineages detected, most of which, however, have not been identified to the species level. At most, approximately 45 morphologically distinct species of Leucocytozoon have been described, but only a few have associated molecular data. This is unfortunate because basic information about named and morphologically recognized Leucocytozoon species is essential for a better understanding of phylogenetically closely related leucocytozoids that are known only by DNA sequence. Despite much research on haemosporidian parasites during the past 30 years, there has not been much progress in taxonomy, vectors, patterns of transmission, pathogenicity, and other aspects of the biology of these cosmopolitan bird pathogens. This study reviewed the available basic information on avian Leucocytozoon species, with particular attention to some obstacles that prevent progress to better understanding the biology of leucocytozoids. Major gaps in current Leucocytozoon species research are discussed, and possible approaches are suggested to resolve some issues that have limited practical parasitological studies of these pathogens.
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A novel gyrovirus is abundant in yellow-eyed penguin (Megadyptes antipodes) chicks with a fatal respiratory disease. Virology 2023; 579:75-83. [PMID: 36608597 DOI: 10.1016/j.virol.2022.12.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/12/2022] [Accepted: 12/23/2022] [Indexed: 01/04/2023]
Abstract
Yellow-eyed penguins (Megadyptes antipodes), or hoiho in te reo Māori, are predicted to become extinct on mainland Aotearoa New Zealand in the next few decades, with infectious disease a significant contributor to their decline. A recent disease phenomenon termed respiratory distress syndrome (RDS) causing lung pathology has been identified in very young chicks. To date, no causative pathogens for RDS have been identified. In 2020 and 2021, the number of chick deaths from suspected RDS increased four- and five-fold, respectively, causing mass mortality with an estimated mortality rate of >90%. We aimed to identify possible pathogens responsible for RDS disease impacting these critically endangered yellow-eyed penguins. Total RNA was extracted from tissue samples collected during post-mortem of 43 dead chicks and subject to metatranscriptomic sequencing and histological examination. From these data we identified a novel and highly abundant gyrovirus (Anelloviridae) in 80% of tissue samples. This virus was most closely related to Gyrovirus 8 discovered in a diseased seabird, while other members of the genus Gyrovirus include Chicken anaemia virus, which causes severe disease in juvenile chickens. No other exogenous viral transcripts were identified in these tissues. Due to the high relative abundance of viral reads and its high prevalence in diseased animals, it is likely that this novel gyrovirus is associated with RDS in yellow-eyed penguin chicks.
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Tsai MS, Newman C, Macdonald DW, Buesching CD. Stress-Related Herpesvirus Reactivation in Badgers Can Result in Clostridium Proliferation. ECOHEALTH 2021; 18:440-450. [PMID: 34870778 PMCID: PMC8742816 DOI: 10.1007/s10393-021-01568-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 09/21/2021] [Accepted: 10/21/2021] [Indexed: 06/13/2023]
Abstract
Clostridium perfringens is an important food-borne zoonotic pathogen and a member of the commensal gut microbiome of many mammals. Predisposing factors such as coinfection with other pathogens or diet change can, however, cause overgrowth and subsequent disease development. Here we investigated the occurrence of C. perfringens in a free-ranging badger population with up to 100% prevalence of herpesvirus infection. Herpesvirus reactivation is known to be associated with increased susceptibility bacterial infections. PCR screening of rectal swabs from 69 free-ranging badgers revealed 15.9% (11/69, 95% CI = 9.1-26.3%) prevalence of detectable C. perfringens (Type A) DNA in the digestive tracts of assymptomatic animals. The results of Fisher's exact test revealed C. perfringens detection was not biased by age, sex and seasons. However, badgers with genital tract gammaherpesvirus (MusGHV-1) reactivation (p = 0.007) and infection with a specific MusGHV-1 genotype (p = 0.019) were more prone to of C. perfringens proliferation, indicating coinfection biased dynamics of intestinal C. perfringens. An inclusion pattern analysis further indicated that, causally, MusGHV-1 reactivation potentiated C. perfringens detection. Whether or not specific MusGHV-1 genotype infection or reactivation plays a role in C. perfringens overgrowth or disease development in badgers will require further investigation. Nevertheless, a postmortem examination of a single badger that died of fatal disease, likely associated with C. perfringens, revealed MusGHV-1 detection in the small intestine.
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Affiliation(s)
- Ming-Shan Tsai
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Recanati-Kaplan Centre, Abingdon Road, Tubney House, Tubney, Oxfordshire, OX13 5QL, UK.
| | - Chris Newman
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Recanati-Kaplan Centre, Abingdon Road, Tubney House, Tubney, Oxfordshire, OX13 5QL, UK
- Cook's Lake Farming Forestry and Wildlife Inc (Ecological Consultancy), Queens County, NS, Canada
| | - David W Macdonald
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Recanati-Kaplan Centre, Abingdon Road, Tubney House, Tubney, Oxfordshire, OX13 5QL, UK
| | - Christina D Buesching
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Recanati-Kaplan Centre, Abingdon Road, Tubney House, Tubney, Oxfordshire, OX13 5QL, UK
- Cook's Lake Farming Forestry and Wildlife Inc (Ecological Consultancy), Queens County, NS, Canada
- Department of Biology, Irving K. Barber Faculty of Science, The University of British Columbia, Okanagan, Kelowna, BC, Canada
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Ben-Gigirey B, Soliño L, Bravo I, Rodríguez F, Casero MVM. Paralytic and Amnesic Shellfish Toxins Impacts on Seabirds, Analyses and Management. Toxins (Basel) 2021; 13:454. [PMID: 34209782 PMCID: PMC8309893 DOI: 10.3390/toxins13070454] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/24/2021] [Accepted: 06/24/2021] [Indexed: 11/30/2022] Open
Abstract
Marine biotoxins have been frequently implicated in morbidity and mortality events in numerous species of birds worldwide. Nevertheless, their effects on seabirds have often been overlooked and the associated ecological impact has not been extensively studied. On top of that, the number of published studies confirming by analyses the presence of marine biotoxins from harmful algal blooms (HABs) in seabirds, although having increased in recent years, is still quite low. This review compiles information on studies evidencing the impact of HAB toxins on marine birds, with a special focus on the effects of paralytic and amnesic shellfish toxins (PSTs and ASTs). It is mainly centered on studies in which the presence of PSTs and/or ASTs in seabird samples was demonstrated through analyses. The analytical techniques commonly employed, the tissues selected and the adjustments done in protocols for processing seabird matrixes are summarized. Other topics covered include the role of different vectors in the seabird intoxications, information on clinical signs in birds affected by PSTs and ASTs, and multifactorial causes which could aggravate the syndromes. Close collaboration between seabird experts and marine biotoxins researchers is needed to identify and report the potential involvement of HABs and their toxins in the mortality events. Future studies on the PSTs and ASTs pharmacodynamics, together with the establishment of lethal doses in various seabird species, are also necessary. These studies would aid in the selection of the target organs for toxins analyses and in the postmortem intoxication diagnoses.
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Affiliation(s)
- Begoña Ben-Gigirey
- Centro Oceanográfico de Vigo (IEO, CSIC), 36390 Vigo, Spain; (L.S.); (I.B.); (F.R.)
| | - Lucía Soliño
- Centro Oceanográfico de Vigo (IEO, CSIC), 36390 Vigo, Spain; (L.S.); (I.B.); (F.R.)
| | - Isabel Bravo
- Centro Oceanográfico de Vigo (IEO, CSIC), 36390 Vigo, Spain; (L.S.); (I.B.); (F.R.)
| | - Francisco Rodríguez
- Centro Oceanográfico de Vigo (IEO, CSIC), 36390 Vigo, Spain; (L.S.); (I.B.); (F.R.)
| | - María V. M. Casero
- RIAS Wildlife Rehabilitation and Research Centre, Parque Natural da Ria Formosa, 8700-194 Olhão, Portugal;
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Phylogenomic Characterization of a Novel Corynebacterium Species Associated with Fatal Diphtheritic Stomatitis in Endangered Yellow-Eyed Penguins. mSystems 2021; 6:e0032021. [PMID: 34100641 PMCID: PMC8269222 DOI: 10.1128/msystems.00320-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Yellow-eyed penguins, Megadyptes antipodes, are an endangered species that are endemic to New Zealand. Outbreaks of diphtheritic stomatitis have caused significant mortality for this species, especially among young chicks. In this study, we isolated 16 Corynebacterium sp. isolates from the oral cavities of 2- to 14-day-old chicks at a range of infection stages and sequenced the genomes to understand their virulence mechanisms. Phylogenomic and matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) characterization indicate that these strains belong to a novel Corynebacterium species. A simple multiplex PCR-based diagnostic assay has been developed to identify these strains rapidly and reliably. Similar to other corynebacteria, genomic islands and prophages introduced significant diversity among these strains that has potentially led to minor functional variations between the two lineages. Despite the presence of multiple corynebacterial virulence genes and a spaDEF-type pilus gene cluster among these strains, the survival rate was much higher in Galleria mellonella larvae than in those inoculated with Corynebacterium ulcerans NZRM 818 and Corynebacterium pseudotuberculosis NZRM 3004. Therefore, these strains are opportunistic pathogens causing high mortality among young penguin chicks due to a less-developed immune system. IMPORTANCE Yellow-eyed penguins, Megadyptes antipodes, are endangered species with a sharp decline in the numbers of breeding pairs over the last 2 decades. Diphtheritic stomatitis, characterized by a thick fibrinopurulent exudate in the oral cavities and symptoms, including inanition and significant weight loss, is responsible for significant mortality among the young chicks. These chicks are treated with antibiotics, amoxicillin-clavulanic acid or enrofloxacin, but do not always recover from the infection. The pathogen causing these infections and the mechanism of pathogenesis are unclear. This study has identified a novel Corynebacterium species to be associated with diphtheritic stomatitis in yellow-eyed penguins with potential virulence genes that are likely involved in pathogenesis. Importantly, a gene encoding an exotoxin, phospholipase D, is present among these strains. The inactivated form of this enzyme could potentially be used as an effective vaccine to protect these penguins from infection.
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Quinete N, Hauser-Davis RA, Lemos LS, Moura JF, Siciliano S, Gardinali PR. Occurrence and tissue distribution of organochlorinated compounds and polycyclic aromatic hydrocarbons in Magellanic penguins (Spheniscus magellanicus) from the southeastern coast of Brazil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 749:141473. [PMID: 32836122 DOI: 10.1016/j.scitotenv.2020.141473] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 08/01/2020] [Accepted: 08/02/2020] [Indexed: 06/11/2023]
Abstract
Seabirds are suitable biomonitors for several persistent organic pollutants (POP), such as polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs), although scarce studies of PAHs in seabirds are available, especially in South American populations. Therefore, this study aimed to assess OCPs, PCBs and PAHs, through gas chromatography-electron capture detector (GC-ECD) and gas chromatography-mass spectrometry (GC-MS) analyses, in liver (n = 9) and muscle tissue (n = 13) from juvenile Magellanic penguins (Spheniscus magellanicus) found stranded on the coast of Rio de Janeiro, Southeastern Brazil. DDT-related compounds were the most frequently detected OCP, and 4,4'-dichlorodiphenyldichloroethylene (DDE), the main DDT metabolite found in penguin tissues. OCP concentrations in liver were two-fold higher than in muscle tissues. Compound specific ratios identified recent exposure of penguins to some OCPs as well as evidence of legacy pollution associated with industrial sources. The predominant PCB congeners were PCB 8/5, PCB 138/160 and PCB 153/132, with concentrations ranging from <LOQ and 1500 ng g-1 dry weight. This study comprises one of the few PAHs reports in penguin tissues, and, although most compounds were detected at very low levels or below the limit of quantitation (LOQ), the concentrations reported herein were up to 100-fold higher than in previous studies in penguins. Therefore, considering penguin vulnerability to marine oil spills during migration routes, further assessments are required in different tissues in order to assess potential environmental health risks to these sentinel species.
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Affiliation(s)
- Natalia Quinete
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Modesto A. Maidique Campus, Miami, FL 33199, USA; Institute of Environment and Southeast Environmental Research Center, Florida International University, 11200 SW 8th Street, Modesto A. Maidique Campus, Miami, FL 33199, USA.
| | - Rachel Ann Hauser-Davis
- Grupo de Estudos de Mamíferos Marinhos da Região dos Lagos (GEMM-Lagos), Rua São José 1.260, Praia Seca, Araruama, RJ 28970-000, Brazil; Laboratório de Avaliação e Promoção da Saúde Ambiental, Instituto Oswaldo Cruz/Fiocruz, Av. Brazil, 4.365, Manguinhos, Rio de Janeiro, RJ 21040-360, Brazil
| | - Leila S Lemos
- Grupo de Estudos de Mamíferos Marinhos da Região dos Lagos (GEMM-Lagos), Rua São José 1.260, Praia Seca, Araruama, RJ 28970-000, Brazil; Marine Mammal Institute, Hatfield Marine Science Center, Oregon State University, 2030 SE Marine Science Dr, Newport, OR 97365, USA
| | - Jailson F Moura
- Grupo de Estudos de Mamíferos Marinhos da Região dos Lagos (GEMM-Lagos), Rua São José 1.260, Praia Seca, Araruama, RJ 28970-000, Brazil; Systems Ecology Group, Leibniz Centre for Tropical Marine Research, Fahrenheitstraße 6, 28359 Bremen, Germany
| | - Salvatore Siciliano
- Grupo de Estudos de Mamíferos Marinhos da Região dos Lagos (GEMM-Lagos), Rua São José 1.260, Praia Seca, Araruama, RJ 28970-000, Brazil; Laboratório de Biodiversidade, Instituto Oswaldo Cruz, Fiocruz, Pavilhão Mourisco sala 217, Av. Brasil, 4.365, Manguinhos, Rio de Janeiro, RJ 21040-900, Brazil
| | - Piero R Gardinali
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Modesto A. Maidique Campus, Miami, FL 33199, USA; Institute of Environment and Southeast Environmental Research Center, Florida International University, 11200 SW 8th Street, Modesto A. Maidique Campus, Miami, FL 33199, USA
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Boersma P, Borboroglu PG, Gownaris N, Bost C, Chiaradia A, Ellis S, Schneider T, Seddon P, Simeone A, Trathan P, Waller L, Wienecke B. Applying science to pressing conservation needs for penguins. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2020; 34:103-112. [PMID: 31257646 PMCID: PMC7027562 DOI: 10.1111/cobi.13378] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 06/25/2019] [Accepted: 06/25/2019] [Indexed: 05/29/2023]
Abstract
More than half of the world's 18 penguin species are declining. We, the Steering Committee of the International Union for Conservation of Nature Species Survival Commission Penguin Specialist Group, determined that the penguin species in most critical need of conservation action are African penguin (Spheniscus demersus), Galápagos penguin (Spheniscus mendiculus), and Yellow-eyed penguin (Megadyptes antipodes). Due to small or rapidly declining populations, these species require immediate scientific collaboration and policy intervention. We also used a pairwise-ranking approach to prioritize research and conservation needs for all penguins. Among the 12 cross-taxa research areas we identified, we ranked quantifying population trends, estimating demographic rates, forecasting environmental patterns of change, and improving the knowledge of fisheries interactions as the highest priorities. The highest ranked conservation needs were to enhance marine spatial planning, improve stakeholder engagement, and develop disaster-management and species-specific action plans. We concurred that, to improve the translation of science into effective conservation for penguins, the scientific community and funding bodies must recognize the importance of and support long-term research; research on and conservation of penguins must expand its focus to include the nonbreeding season and juvenile stage; marine reserves must be designed at ecologically appropriate spatial and temporal scales; and communication between scientists and decision makers must be improved with the help of individual scientists and interdisciplinary working groups.
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Affiliation(s)
- P.D. Boersma
- Center for Ecosystem Sentinels and Department of BiologyUniversity of WashingtonSeattleWA98103U.S.A.
- Global Penguin SocietyPuerto Madryn9120Argentina
| | - P. García Borboroglu
- Center for Ecosystem Sentinels and Department of BiologyUniversity of WashingtonSeattleWA98103U.S.A.
- Global Penguin SocietyPuerto Madryn9120Argentina
- CESIMAR CCT Cenpat‐CONICET9120Puerto MadrynChubutArgentina
| | - N.J. Gownaris
- Center for Ecosystem Sentinels and Department of BiologyUniversity of WashingtonSeattleWA98103U.S.A.
| | - C.A. Bost
- Centre d'Etudes Biologiques de Chizé79360Villiers‐en‐BoisFrance
| | - A. Chiaradia
- Conservation DepartmentPhillip Island Nature ParksCowesVIC3922Australia
| | - S. Ellis
- International Rhino FoundationStrasburgVA22657U.S.A.
| | - T. Schneider
- Detroit Zoological SocietyRoyal OakMI48067U.S.A.
| | - P.J. Seddon
- Department of ZoologyUniversity of OtagoDunedin9016New Zealand
| | - A. Simeone
- Facultad de Ciencias de la VidaUniversidad Andres BelloSantiago8370146Chile
| | | | - L.J. Waller
- Southern African Foundation for the Conservation of Coastal Birds (SANCCOB)Cape Town7441South Africa
- Department of Biodiversity and Conservation BiologyUniversity of the Western CapeBellvilleCape Town7535South Africa
| | - B. Wienecke
- Australian Antarctic DivisionKingstonTAS7050Australia
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Klusener R, Hurtado R, Parsons NJ, Vanstreels RET, Stander N, van der Spuy S, Ludynia K. From incubation to release: Hand-rearing as a tool for the conservation of the endangered African penguin. PLoS One 2018; 13:e0205126. [PMID: 30403662 PMCID: PMC6221267 DOI: 10.1371/journal.pone.0205126] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 09/19/2018] [Indexed: 11/19/2022] Open
Abstract
The African penguin (Spheniscus demersus) population is estimated at 25,000 breeding pairs, approximately 5% of that at the start of the 20th century, and the species is currently classified as Endangered. In the last two decades, the hand-rearing of penguin chicks that were abandoned by their parents due to oil spills or other circumstances has become a valuable conservation tool to limit mortality and to bolster the population at specific colonies. We summarize and evaluate the techniques employed by the Southern African Foundation for the Conservation of Coastal Birds (SANCCOB) to incubate and hand-rear African penguin eggs and chicks. From 2012 to 2016, a total of 694 eggs and 2819 chicks were received by SANCCOB’s Chick Rearing Unit. It was estimated that 13% of the eggs were infertile, and 81% of the fertile eggs hatched successfully. The overall release rate for chicks was 77%, with a higher release rate for chicks that were pre-emptively removed (93%) followed by chicks that had been abandoned by their parents (78%), chicks admitted due to avian pox lesions (61%), chicks that hatched from artificially-incubated eggs (57%), and chicks admitted due to injuries or deformities (25%). Rescuing and hand-rearing eggs and chicks has been a successful strategy for African penguins, and might be also applicable for the conservation of other threatened seabird species whose population are critically low or during natural or anthropogenic events that could have disastrous population impacts (e.g. oil spills, disease outbreaks, catastrophic weather events, strong El Niño years, etc.).
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Affiliation(s)
- Romy Klusener
- Southern African Foundation for the Conservation of Coastal Birds, Cape Town, Western Cape, South Africa
- * E-mail:
| | - Renata Hurtado
- Southern African Foundation for the Conservation of Coastal Birds, Cape Town, Western Cape, South Africa
- Institute of Research and Rehabilitation of Marine Animals, Cariacica, Espírito Santo, Brazil
| | - Nola J. Parsons
- Southern African Foundation for the Conservation of Coastal Birds, Cape Town, Western Cape, South Africa
| | - Ralph Eric Thijl Vanstreels
- Marine Apex Predator Research Unit, Institute for Coastal and Marine Research, Nelson Mandela University, Port Elizabeth, Eastern Cape, South Africa
- DST-NRF Centre of Excellence at the FitzPatrick Institute for African Ornithology, Department of Zoology, Nelson Mandela University, Port Elizabeth, Eastern Cape, South Africa
| | - Nicola Stander
- Southern African Foundation for the Conservation of Coastal Birds, Cape Town, Western Cape, South Africa
| | - Stephen van der Spuy
- Southern African Foundation for the Conservation of Coastal Birds, Cape Town, Western Cape, South Africa
| | - Katrin Ludynia
- Southern African Foundation for the Conservation of Coastal Birds, Cape Town, Western Cape, South Africa
- Department of Biological Sciences, University of Cape Town, Cape Town, Western Cape, South Africa
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Abstract
Our knowledge of diseases in New Zealand wildlife has expanded rapidly in the last two decades. Much of this is due to a greater awareness of disease as a cause of mortality in some of our highly threatened species or as a limiting factor to the successful captive rearing of intensely managed species such as hihi (Notiomystis cincta), kiwi (Apteryx spp.) and kakapo (Strigops habroptilus). An important factor contributing to the increase of our knowledge has been the development of new diagnostic techniques in the fields of molecular biology and immunohistochemistry, particularly for the diagnosis and epidemiology of viral and protozoan diseases. Although New Zealand remains free of serious exotic viruses there has been much work on understanding the taxonomy and epidemiology of local strains of avipox virus and circoviruses. Bacterial diseases such as salmonellosis, erysipelas and tuberculosis have also been closely investigated in wildlife and opportunist mycotic infections such as aspergillosis remain a major problem in many species. Nutritional diseases such as hyperplastic goitre due to iodine deficiency and metabolic bone disease due to Ca:P imbalance have made significant impacts on some captive reared birds, while lead poisoning is a problem in some localities. The increasing use of wildlife translocations to avoid the extinction of threatened species has highlighted the need for improved methods to assess the disease risks inherent in these operations and other intensive conservation management strategies such as creching young animals. We have also become more aware of the likelihood of inbreeding suppression as populations of many species decrease or pass through a genetic bottleneck. Climate change and habitat loss, however, remain the greatest threats to biodiversity and wildlife health worldwide. Temperature changes will affect our wildlife habitats, alter the distribution of disease vectors and wildlife predators, or directly harm threatened species in vulnerable localities.
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Affiliation(s)
- M R Alley
- a Wildbase, School of Veterinary Science , Massey University , Private Bag 11-222, Palmerston North 4442 , New Zealand
| | - B D Gartrell
- a Wildbase, School of Veterinary Science , Massey University , Private Bag 11-222, Palmerston North 4442 , New Zealand
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10
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Mattern T, Meyer S, Ellenberg U, Houston DM, Darby JT, Young M, van Heezik Y, Seddon PJ. Quantifying climate change impacts emphasises the importance of managing regional threats in the endangered Yellow-eyed penguin. PeerJ 2017; 5:e3272. [PMID: 28533952 PMCID: PMC5436559 DOI: 10.7717/peerj.3272] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 03/28/2017] [Indexed: 11/20/2022] Open
Abstract
Climate change is a global issue with effects that are difficult to manage at a regional scale. Yet more often than not climate factors are just some of multiple stressors affecting species on a population level. Non-climatic factors—especially those of anthropogenic origins—may play equally important roles with regard to impacts on species and are often more feasible to address. Here we assess the influence of climate change on population trends of the endangered Yellow-eyed penguin (Megadyptes antipodes) over the last 30 years, using a Bayesian model. Sea surface temperature (SST) proved to be the dominating factor influencing survival of both adult birds and fledglings. Increasing SST since the mid-1990s was accompanied by a reduction in survival rates and population decline. The population model showed that 33% of the variation in population numbers could be explained by SST alone, significantly increasing pressure on the penguin population. Consequently, the population becomes less resilient to non-climate related impacts, such as fisheries interactions, habitat degradation and human disturbance. However, the extent of the contribution of these factors to declining population trends is extremely difficult to assess principally due to the absence of quantifiable data, creating a discussion bias towards climate variables, and effectively distracting from non-climate factors that can be managed on a regional scale to ensure the viability of the population.
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Affiliation(s)
- Thomas Mattern
- Department of Zoology, University of Otago, Dunedin, New Zealand
| | - Stefan Meyer
- Department of Zoology, University of Otago, Dunedin, New Zealand
| | - Ursula Ellenberg
- Department of Ecology, Environment and Evolution, La Trobe University, Melbourne, Australia
| | - David M Houston
- Science and Policy Group, Department of Conservation, Auckland, New Zealand
| | | | - Melanie Young
- Department of Zoology, University of Otago, Dunedin, New Zealand
| | | | - Philip J Seddon
- Department of Zoology, University of Otago, Dunedin, New Zealand
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