Search Results - "Ward Testa, J."

Reproductive success delays moult phenology in a polar mammal by Beltran, Roxanne S., Kirkham, Amy L., Breed, Greg A., Testa, J. Ward, Burns, Jennifer M.

“…Animals can respond to dynamic environments through phenological plasticity of life history events; however, changes in one part of the annual cycle can…”
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Life history and population dynamics of southern Alaska resident killer whales (Orcinus orca) by Matkin, Craig O., Ward Testa, J., Ellis, Graeme M., Saulitis, Eva L.

“…Resident (fish eating) killer whales (Orcinus orca) in the North Pacific have been the subject of long‐term studies in several geographical regions. The…”
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Replicating necropsy data without lethal collections: using ultrasonography to understand the decline in northern fur seals by Testa, J. Ward, Adams, Gregg P., Bergfelt, Don R., Johnson, Devin S., Ream, Rolf R., Gelatt, Thomas S.

“…1. Many valuable contributions to the biology and conservation of harvested or previously harvested species have come from examination of specimens obtained by…”
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Evaluating Cementum to Determine Past Reproduction in Northern Sea Otters by von Biela, Vanessa R, Testa, J. Ward, Gill, Verena A, Burns, Jennifer M

“…Age at first reproduction (AFR) has been difficult to quantify in mammals, as the most commonly used methods require reproductive tracts or direct…”
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Pairing ultrasonography with endocrinology to elucidate underlying mechanisms of successful pregnancy in the northern fur seal (Callorhinus ursinus) by Shero, Michelle R., Bergfelt, Don R., Testa, J. Ward, Adams, Gregg P.

“…•Stasis of the wild northern fur seal population is not due to loss of fecundity.•Pregnancy rate was high (96%) and pregnancy loss rate was low…”
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ULTRASONOGRAPHIC CHARACTERIZATION OF REPRODUCTIVE ANATOMY AND EARLY EMBRYONIC DETECTION IN THE NORTHERN FUR SEAL (CALLORHINUS URSINUS) IN THE FIELD by Adams, Gregg P., Ward Testa, J., Goertz, Caroline E. C., Ream, Rolf R., Sterling, Jeremy T.

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Population Dynamics and Life History Trade-offs of Moose (Alces alces) in South-Central Alaska by Testa, J. Ward

“…A common framework toward understanding the ecological forces affecting herbivore population dynamics is to partition those forces according to their origin…”
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Exploring Linkages between Abiotic Oceanographic Processes and a Top-trophic Predator in an Antarctic Ecosystem by Proffitt, Kelly M, Garrott, Robert A, Rotella, Jay J, Siniff, Donald B, Testa, J. Ward

“…Climatic variation affects the physical and biological components of ecosystems, and global-climate models predict enhanced sensitivity in polar regions,…”
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Validation of a homologous canine relaxin radioimmunoassay and application with pregnant and non-pregnant Northern fur seals ( Callorhinus ursinus ) by Bergfelt, Don R, Steinetz, Bernard G, Dunn, J. Lawrence, Atkinson, Shannon, Testa, J. Ward, Adams, Gregg P

“…Abstract The primary objectives of this study were to validate a canine relaxin RIA for use in otariids and phocids and consider practical applications. For 6…”
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Interaction of Top-down and Bottom-up Life History Trade-offs in Moose (Alces alces) by Testa, J. Ward

“…Moose (Alces alces) in south-central Alaska have been found to have phenotypic life history trade-offs that can be partitioned into the same "bottom-up" and…”
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DOES PREDATION ON NEONATES INHERENTLY SELECT FOR EARLIER BIRTHS? by Testa, J. Ward

“…I hypothesize that predation on newborn young represents a seasonal analog to time-lagged predator–prey cycles and can cause directional selection against late…”
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Body Condition and Adjustments to Reproductive Effort in Female Moose (Alces alces) by Testa, J. Ward, Adams, Gregg P.

“…We studied condition and reproduction of moose (Alces alces) in southcentral Alaska using ultrasonography to determine rump-fat thickness and numbers of…”
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An agent-based bioenergetics model for predicting impacts of environmental change on a top marine predator, the Weddell seal by Beltran, Roxanne S., Testa, J. Ward, Burns, Jennifer M.

“…•Our agent-based model simulates energy balance of adult, female Weddell seals.•Simulations were run to study the responses of seals to 10% reduced prey.•Prey…”
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Maternal and Birth Colony Effects on Survival of Weddell Seal Offspring from McMurdo Sound, Antarctica by Hastings, Kelly K., Testa, J. Ward

“…1. Maternal and birth colony effects on offspring survival to weaning and to reproductive age were examined for Weddell seals using mark-recapture models and…”
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BEHAVIORAL AND ECOLOGIC EFFECTS OF DIFFERENTIAL PREDATION PRESSURE ON MOOSE IN ALASKA by White, Kevin S., Testa, J. Ward, Berger, Joel

“…We studied behavioral and ecologic effects of differential predation pressure on moose (Alces alces gigas) in the eastern Talkeetna Mountains, Alaska, during…”
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Habitat Selection and Home Ranges of River Otters in a Marine Environment: Effects of the Exxon Valdez Oil Spill by Bowyer, R. Terry, Testa, J. Ward, Faro, James B.

“…We studied habitat selection and home ranges of river otters (Lutra canadensis) living along the coastlines of Prince William Sound, Alaska, following the…”
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ULTRASONOGRAPHIC CHARACTERIZATION OF REPRODUCTIVE ANATOMY AND EARLY EMBRYONIC DETECTION IN THE NORTHERN FUR SEAL (CALLORHINUS URSINUS) IN THE FIELD by Adams, Gregg P, Ward Testa, J, Goertz, Caroline E.C, Ream, Rolf R, Sterling, Jeremy T

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Dynamics of an Isolated Population of Weddell Seals (Leptonychotes weddellii) at White Island, Antarctica by Testa, J. Ward, Scotton, Bradley D.

“…A small population of Weddell seals (Leptonychotes weddellii) was studied at White Island, Antarctica, where it is apparently isolated from other populations…”
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Estimating Populations of Marine River Otters in Prince William Sound, Alaska, Using Radiotracer Implants by Testa, J. Ward, Holleman, Dan F., Bowyer, R. Terry, Faro, James B.

“…One year after the spillage of oil from the Exxon Valdez in spring 1989, we used radiotransmitters and radiotracer labels to mark river otters (Lutra…”
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Population Dynamics of Weddell Seals (Leptonychotes Weddelli) in McMurdo Sound, Antarctica by Testa, J. Ward, Siniff, Donald B.

“…Population dynamics of Weddell seals in McMurdo Sound, Antarctica, were studied from 1970 to 1984 using mark-recapture estimation, aerial surveys, age…”
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