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4. Chemical Immobilization Effects on Cougar (Felis concolor ) Movement.

Author

Littlefair, Carter J., Derocher, Andrew E., Frame, Paul F., Edwards, Mark A., Frame, Delaney D., Slater, Owen M., and Smereka, Corey A.

Abstract

Capturing and handling wildlife is a common practice for both management and research. As telemetry use has become common, the need to capture and chemically immobilize wildlife has increased. Understanding how long the effects of immobilizing agents last after releasing the animal is often poorly understood but needed to ensure that analyses use data that reflect natural behavior. Between 2016 and 2021, 60 cougars (Puma concolor) were chemically immobilized with medetomidine, zolazepam, and tiletamine (MZT) and collared across west-central Alberta, Canada, 27 of which were individuals being recollared. We examined the distance an individual traveled per day and compared equivalent periods before and after the recollaring event to determine whether postcapture movement rates were significantly different from precapture rates. Within 1 d of the recollaring, daily movement rates had returned to precapture rates (t20-2.09, P=0.18). Our results provide insight on how MZT used in cougars affects their postcapture movement and thus may be helpful in interpreting movement data after release. [ABSTRACT FROM AUTHOR]

Published
2024
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7. A demographic survey of the Davis Strait polar bear subpopulation using physical and genetic capture‐recapture‐recovery sampling.

Author

Dunham, Kylee D., Dyck, Markus G., Ware, Jasmine V., Derocher, Andrew E., Regehr, Eric V., Stern, Harry L., Stenson, Garry B., and Koons, David N.

Subjects
POLAR bear, STRAITS, ECOLOGICAL forecasting, DATA recovery, SURVIVAL rate, SAMPLE size (Statistics)
Abstract

Conducting assessments to understand the effects of changing environmental conditions on polar bear (Ursus maritimus) demography has become increasingly important to inform management and conservation. Here, we combined physical (2005–2007) and genetic (2017–2018) mark‐recapture with harvest recovery data (2005–2018) to estimate demographic rates of the Davis Strait polar bear subpopulation and examine the possible effects of climate, dynamic ice habitat, and prey resources on survival. Large sample sizes (e.g., 2,513 marked animals) allowed us to estimate temporal variation in annual survival rates using multistate mark‐recapture‐recovery models. We did not detect statistically significant effects of climate, ice habitat, and prey during the 13‐year study. Estimated total abundance in 2006 was 2,190, credible interval (CRI) [1,954, 2,454] and 1,944, CRI [1,593, 2,366] in 2018. Geometric mean population growth rate (0.99, 95% CRI [0.97, 1.01]) indicated the subpopulation may have declined slightly between 2006 and 2018. However, we did not detect a declining trend in survival or substantial change in reproductive metrics over this period. Given forecasts of major environmental change we emphasize the need to review monitoring programs for this subpopulation. [ABSTRACT FROM AUTHOR]

Published
2024
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11. Abundance and species diversity hotspots of tracked marine predators across the North American Arctic

Author

Yurkowski, David J., Auger-Méthé, Marie, Mallory, Mark L., Wong, Sarah N. P., Gilchrist, Grant, Derocher, Andrew E., Richardson, Evan, Lunn, Nicholas J., Hussey, Nigel E., Marcoux, Marianne, Togunov, Ron R., Fisk, Aaron T., Harwood, Lois A., Dietz, Rune, Rosing-Asvid, Aqqalu, Born, Erik W., Mosbech, Anders, Fort, Jérôme, Grémillet, David, Loseto, Lisa, Richard, Pierre R., Iacozza, John, Jean-Gagnon, Frankie, Brown, Tanya M., Westdal, Kristin H., Orr, Jack, LeBlanc, Bernard, Hedges, Kevin J., Treble, Margaret A., Kessel, Steven T., Blanchfield, Paul J., Davis, Shanti, Maftei, Mark, Spencer, Nora, McFarlane-Tranquilla, Laura, Montevecchi, William A., Bartzen, Blake, Dickson, Lynne, Anderson, Christine, and Ferguson, Steven H.

Published
2019

30. Survival improvements of marine mammals in zoological institutions mirror historical advances in human longevity.

Author

Tidière, Morgane, Colchero, Fernando, Staerk, Johanna, Adkesson, Michael J., Andersen, Ditte H., Bland, Lucie, Böye, Martin, Brando, Sabrina, Clegg, Isabella, Cubaynes, Sarah, Cutting, Amy, De Man, Danny, Derocher, Andrew E., Dorsey, Candice, Elgar, William, Gaglione, Eric, Anderson Hansen, Kirstin, Jungheim, Allison, Kok, José, and Laule, Gail

Subjects
SEA lions, BOTTLENOSE dolphin, HARBOR seal, MARINE mammals, LIFE expectancy, LONGEVITY, POLAR bear
Abstract

An intense public debate has fuelled governmental bans on marine mammals held in zoological institutions. The debate rests on the assumption that survival in zoological institutions has been and remains lower than in the wild, albeit the scientific evidence in support of this notion is equivocal. Here, we used statistical methods previously applied to assess historical improvements in human lifespan and data on 8864 individuals of four marine mammal species (harbour seal, Phoca vitulina; California sea lion, Zalophus californianus; polar bear, Ursus maritimus; common bottlenose dolphin, Tursiops truncatus) held in zoos from 1829 to 2020. We found that life expectancy increased up to 3.40 times, and first-year mortality declined up to 31%, during the last century in zoos. Moreover, the life expectancy of animals in zoos is currently 1.65–3.55 times longer than their wild counterparts. Like humans, these improvements have occurred concurrently with advances in management practices, crucial for population welfare. Science-based decisions will help effective legislative changes and ensure better implementation of animal care. [ABSTRACT FROM AUTHOR]

Published
2023
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35. Anthropogenic food: an emerging threat to polar bears.

Author

Smith, Tom S., Derocher, Andrew E., Mazur, Rachel L., York, Geoff, Owen, Megan A., Obbard, Martyn, Richardson, Evan S., and Amstrup, Steven C.

Subjects
*BLACK bear, *POLAR bear, *BROWN bear, *PROPERTY damage, *MORTALITY, *SOCIAL interaction, *COMMUNITY life
Abstract

Supplemental food from anthropogenic sources is a source of conflict with humans for many wildlife species. Food-seeking behaviours by black bears Ursus americanus and brown bears Ursus arctos can lead to property damage, human injury and mortality of the offending bears. Such conflicts are a well-known conservation management issue wherever people live in bear habitats. In contrast, the use of anthropogenic foods by the polar bear Ursus maritimus is less common historically but is a growing conservation and management issue across the Arctic. Here we present six case studies that illustrate how negative food-related interactions between humans and polar bears can become either chronic or ephemeral and unpredictable. Our examination suggests that attractants are an increasing problem, exacerbated by climate change-driven sea-ice losses that cause increased use of terrestrial habitats by bears. Growing human populations and increased human visitation increase the likelihood of human–polar bear conflict. Efforts to reduce food conditioning in polar bears include attractant management, proactive planning and adequate resources for northern communities to reduce conflicts and improve human safety. Permanent removal of unsecured sources of nutrition, to reduce food conditioning, should begin immediately at the local level as this will help to reduce polar bear mortality. [ABSTRACT FROM AUTHOR]

Published
2023
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47. The Impact of Conservation on the Status of the World's Vertebrates

Author

Hoffmann, Michael, Hilton-Taylor, Craig, Angulo, Ariadne, Böhm, Monika, Brooks, Thomas M., Butchart, Stuart H. M., Carpenter, Kent E., Chanson, Janice, Collen, Ben, Cox, Neil A., Darwall, William R. T., Dulvy, Nicholas K., Harrison, Lucy R., Katariya, Vineet, Pollock, Caroline M., Quader, Suhel, Richman, Nadia I., Rodrigues, Ana S. L., Tognelli, Marcelo F., Vie, Jean-Christophe, Aguiar, John M., Allen, David J., Allen, Gerald R., Amori, Giovanni, Ananjeva, Natalia B., Andreone, Franco, Andrew, Paul, Ortiz, Aida Luz Aquino, Baillie, Jonathan E. M., Baldi, Ricardo, Bell, Ben D., Biju, S. D., Bird, Jeremy P., Black-Decima, Patricia, Blanc, J. Julian, Bolaños, Federico, Bolivar-G., Wilmar, Burfield, Ian J., Burton, James A., Capper, David R., Castro, Fernando, Catullo, Gianluca, Cavanagh, Rachel D., Channing, Alan, Chao, Ning Labbish, Chenery, Anna M., Chiozza, Federica, Clausnitzer, Viola, Collar, Nigel J., Collett, Leah C., Collette, Bruce B., Fernandez, Claudia F. Cortez, Craig, Matthew T., Crosby, Michael J., Cumberlidge, Neil, Cuttelod, Annabelle, Derocher, Andrew E., Diesmos, Arvin C., Donaldson, John S., Duckworth, J. W., Dutson, Guy, Dutta, S. K., Emslie, Richard H., Farjon, Aljos, Fowler, Sarah, Freyhof, Jörg, Garshelis, David L., Gerlach, Justin, Gower, David J., Grant, Tandora D., Hammerson, Geoffrey A., Harris, Richard B., Heaney, Lawrence R., Hedges, S. Blair, Hero, Jean-Marc, Hughes, Baz, Hussain, Syed Ainul, Icochea M., Javier, Inger, Robert F., Ishii, Nobuo, Iskandar, Djoko T., Jenkins, Richard K. B., Kaneko, Yoshio, Kottelat, Maurice, Kovacs, Kit M., Kuzmin, Sergius L., La Marca, Enrique, Lamoreux, John F., Lau, Michael W. N., Lavilla, Esteban O., Leus, Kristin, Lewison, Rebecca L., Lichtenstein, Gabriela, Livingstone, Suzanne R., Lukoschek, Vimoksalehi, Mallon, David P., McGowan, Philip J. K., Mclvor, Anna, Moehlman, Patricia D., Molur, Sanjay, Alonso, Antonio Muñoz, Musick, John A., Nowell, Kristin, Nussbaum, Ronald A., Olech, Wanda, Orlov, Nikolay L., Papenfuss, Theodore J., Parra-Olea, Gabriela, Perrin, William F., Polidoro, Beth A., Pourkazemi, Mohammad, Racey, Paul A., Ragle, James S., Ram, Mala, Rathbun, Galen, Reynolds, Robert P., Rhodin, Anders G. J., Richards, Stephen J., Rodríguez, Lily O., Ron, Santiago R., Rondinini, Carlo, Rylands, Anthony B., de Mitcheson, Yvonne Sadovy, Sanciangco, Jonnell C., Sanders, Kate L., Santos-Barrera, Georgina, Schipper, Jan, Self-Sullivan, Caryn, Shi, Yichuan, Shoemaker, Alan, Short, Frederick T., Sillero-Zubiri, Claudio, Silvano, Débora L., Smith, Kevin G., Smith, Andrew T., Snoeks, Jos, Stattersfield, Alison J., Symes, Andrew J., Taber, Andrew B., Talukdar, Bibhab K., Temple, Helen J., Timmins, Rob, Tobias, Joseph A., Tsytsulina, Katerina, Tweddle, Denis, Ubeda, Carmen, Valenti, Sarah V., van Dijk, Peter Paul, Veiga, Liza M., Veloso, Alberto, Wege, David C., Wilkinson, Mark, Williamson, Elizabeth A., Xie, Feng, Young, Bruce E., Akçakaya, H. Resit, Bennun, Leon, Blackburn, Tim M., Boitani, Luigi, Dublin, Holly T., da Fonseca, Gustavo A. B., Gascon, Claude, Lacher, Thomas E., Mace, Georgina M., Mainka, Susan A., McNeely, Jeffery A., Mittermeier, Russell A., Reid, Gordon McGregor, Rodriguez, Jon Paul, Rosenberg, Andrew A., Samways, Michael J., Smart, Jane, Stein, Bruce A., and Stuart, Simon N.

Published
2010

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