Article
Multidisciplinary Sciences
Nelle Meyers, Cassie N. Speakman, Nicole A. S-Y Dorville, Mark A. Hindell, Jayson M. Semmens, Jacquomo Monk, Alistair M. M. Baylis, Daniel Ierodiaconou, Andrew J. Hoskins, Greg J. Marshall, Kyler Abernathy, John P. Y. Arnould
Summary: In this study, the foraging behavior of female Australian fur seals was investigated using animal-borne video data loggers. The study found substantial differences in pursuit and handling times, energy gain, and expenditure between different prey types, but overall profitability did not significantly differ between prey types, except for elasmobranchs. The study highlights the benefits of using animal-borne video data loggers for understanding the factors influencing foraging decisions in predators.
Article
Environmental Sciences
Johanna J. Geeson, Mark A. Hindell, Alistair J. Hobday, Cassie N. Speakman, John P. Y. Arnould
Summary: The Australian fur seal population is recovering but experiencing changing nutritional conditions, which may continue to decline under predicted climate change conditions.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Ecology
Kayleigh A. Jones, Norman Ratcliffe, Stephen C. Votier, Simeon Lisovski, Anne-Sophie Bonnet-Lebrun, Iain J. Staniland
Summary: Research has shown that sexual segregation occurs in juvenile Antarctic fur seals, primarily in foraging distribution, with females foraging closer to South Georgia and the Polar Front, while males forage further south near the Antarctic Peninsula. This segregation is particularly evident in Feb-Apr and May-Nov, with males spending more time hauled out than females in May-Nov. Sex differences in body size, risk-taking, and social roles may contribute to this segregation.
Article
Ecology
Jonathan A. Botha, Clive N. Trueman, Stephen P. Kirkman, John P. Y. Arnould, Amanda T. Lombard, Maelle Connan, G. J. Greg Hofmeyr, S. Mduduzi Seakamela, Pierre A. Pistorius
Summary: This study investigated the trophic ecology of Cape fur seals breeding in South Africa by analyzing the carbon and nitrogen isotopic compositions of whiskers collected at four breeding sites. The results revealed geographic variability and individual specialization in resource and habitat use, emphasizing the importance of considering variability when assessing the foraging ecology of marine predators.
ECOLOGY AND EVOLUTION
(2023)
Article
Ecology
Renan C. de Lima, Valentina Franco-Trecu, Thayara S. Carrasco, Pablo Inchausti, Eduardo R. Secchi, Silvina Botta
Summary: The study found differences in isotopic niche width and overlap between male and female South American fur seals, with males showing higher values. There was minimal isotopic niche overlap between sexes and limited seasonal variation. Females had a wider isotopic niche in spring compared to other seasons.
Article
Multidisciplinary Sciences
Johanna J. Geeson, Alistair J. Hobday, Cassie N. Speakman, John P. Y. Arnould
Summary: Understanding the breeding biology of a species is important for predicting its response to global change. This study investigated the breeding phenology and pup production of the Australian fur seal on Kanowna Island and found correlations with winter and summer winds and climate indices.
ROYAL SOCIETY OPEN SCIENCE
(2022)
Article
Behavioral Sciences
Mathilde Chevallay, Christophe Guinet, Tiphaine Jeanniard-Du-Dot
Summary: Understanding the foraging strategies and decision-making processes of Antarctic fur seals and Northern fur seals provides insights into their response to changes in prey availability. Our study found that both species adjust their foraging behavior based on past prey capture experiences, but respond differently depending on their foraging strategy and targeted prey. Seals adjust their movement and diving patterns in response to a decrease in prey capture success, with variations between species and habitats.
BEHAVIORAL ECOLOGY
(2022)
Article
Environmental Sciences
Shichao Pei, Xiangliang Zhang, Victor M. Eguiluz, Sarah S. Kienle, Patrick W. Robinson, Daniel P. Costa, Carlos M. Duarte
Summary: Northern elephant seals, known for their large-scale foraging migrations, exhibit surprising coherence in female seals' migratory behavior. Patterns of movement remained coherent until the seals were 1,000 km away from the colony, beyond which coherence declined. Regional aggregations were observed, with female seals traveling within the center and isolated individuals on the edges. The presence of synchronized movement was demonstrated, suggesting the influence of both internal and external cues on migration timing.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Brett R. Gardner, John Stenos, Jasmin Hufschmid, John P. Y. Arnould, Rebecca R. McIntosh, Mythili Tadepalli, Anita Tolpinrud, Marc Marenda, Michael Lynch, Andrew Stent
Summary: The Australian fur seal has been experiencing a slower population recovery than expected, with a high rate of third trimester abortions. The cause of this phenomenon is currently unknown. This study found evidence of Coxiella burnetii, a well-known cause of abortion, in Australian fur seals. This is the first description of this pathogen in a marine mammal from the southern hemisphere and highlights the need for further research on its potential risks to fur seals and other marine mammals.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Genetics & Heredity
Jaime A. Chaves, Fernando Lopes, Daniela Martinez, Dario F. Cueva, Gabriela I. Gavilanes, Sandro L. Bonatto, Larissa Rosa de Oliveira, Diego Paez-Rosas
Summary: The genetic consequences of the geographic distribution of rookeries in Galapagos fur seals were investigated. The results showed that the rookeries on four islands were genetically structured into three main groups. Gene flow analysis suggested migration from west Isabela to Fernandina islands, with limited migration in other directions.
FRONTIERS IN GENETICS
(2022)
Article
Multidisciplinary Sciences
Kimberley Kliska, Rebecca R. McIntosh, Ian Jonsen, Fiona Hume, Peter Dann, Roger Kirkwood, Robert Harcourt
Summary: The study found that the diet of Australian fur seals has changed over the past 17 years, influenced by both large-scale and regional environmental factors. Changes in the frequency of occurrence of prey species were correlated with environmental variables such as wind, sea surface temperature, and climate indices.
ROYAL SOCIETY OPEN SCIENCE
(2022)
Article
Multidisciplinary Sciences
Kimberley Kliska, Rebecca R. McIntosh, Ian Jonsen, Fiona Hume, Peter Dann, Roger Kirkwood, Robert Harcourt
Summary: Marine ecosystems in southeastern Australia are rapidly responding to climate change, as evidenced by changes in the diet of the Australian fur seal. The frequency of occurrence of prey taxa changed over time, and correlations were found with environmental variables at both local and regional scales. The study predicts that the Australian fur seal's diverse diet will be advantageous in a rapidly changing ecosystem.
ROYAL SOCIETY OPEN SCIENCE
(2022)
Article
Environmental Sciences
Mickie R. Edwards, Susana Cardenas-Alayza, Michael J. Adkesson, Mya Daniels-Abdulahad, Amy C. Hirons
Summary: Peru's coastal waters experience significant environmental fluctuations due to El Nino-La Nina-Southern Oscillation events, impacting the food web and diet of Peruvian fur seals. Stable isotope ratios are used to infer primary production and dietary variations, with correlations between N-15 values and ENSO conditions. The study suggests that ENSO conditions influence resource availability, potentially affecting pinniped foraging behavior and food web complexity.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Multidisciplinary Sciences
Connor C. G. Bamford, Victoria Warwick-Evans, Iain J. Staniland, Jennifer A. Jackson, Philip N. Trathan
Summary: Antarctic fur seals at South Georgia primarily feed on Antarctic krill, with foraging trips limited by the need to provision their pups. After breeding, female seals disperse to feed and recover condition, with potential interaction with the krill fishery at South Georgia during the winter months. Tracking data from female fur seals in winters of 1999 and 2003 reveals extensive distribution around South Georgia, with small areas of overlap with the krill fishery. These findings have implications for management and future research.
Article
Fisheries
Massimiliano Drago, Celia Llorach, Unai Ormazabal Santa Cruz, Lisette Zenteno-Devaud, Lorena Rebolledo, Diego Rita, Manel Gazo, Luis Cardona
Summary: This study used stable isotope ratios in whiskers and blood of young and subadult male Antarctic fur seals to investigate their diet. The results showed that Antarctic fur seals rely predominantly on Antarctic krill year-round, with penguins as their secondary prey. These findings highlight the importance of considering the dietary reliance of young and subadult male Antarctic fur seals in ecosystem-based fisheries management.
CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES
(2023)
Review
Multidisciplinary Sciences
Carlos M. Duarte, Lucille Chapuis, Shaun P. Collin, Daniel P. Costa, Reny P. Devassy, Victor M. Eguiluz, Christine Erbe, Timothy A. C. Gordon, Benjamin S. Halpern, Harry R. Harding, Michelle N. Havlik, Mark Meekan, Nathan D. Merchant, Jennifer L. Miksis-Olds, Miles Parsons, Milica Predragovic, Andrew N. Radford, Craig A. Radford, Stephen D. Simpson, Hans Slabbekoorn, Erica Staaterman, Ilse C. Van Opzeeland, Jana Winderen, Xiangliang Zhang, Francis Juanes
Summary: Oceans have become noisier due to human activities since the Industrial Revolution, affecting both biological and abiotic sounds. Climate change also plays a role in altering natural sounds in the oceans. The increased noise levels in the ocean pose threats to marine animals' behavior, physiology, and survival, prompting the need for management actions to mitigate the impact.
Article
Ecology
Cassie N. Speakman, Sebastian T. Lloyd, Elodie C. M. Camprasse, Andrew J. Hoskins, Mark A. Hindell, Daniel P. Costa, John P. Y. Arnould
Summary: Variation in foraging strategies can exist within populations, with individual consistency playing a key role in benthic diving activities. Consistency in foraging behavior contributes to individual success and efficiency during feeding activities.
ECOLOGY AND EVOLUTION
(2021)
Article
Biology
Jane Khudyakov, Rachel R. Holser, Craig A. Vierra, Serena T. Ly, Theron K. Niel, Basma M. Hasan, Daniel E. Crocker, Daniel P. Costa
Summary: Northern elephant seals undergo prolonged fasting during energy-intensive life-history stages and display unique metabolic features. Changes in apolipoprotein composition may play a role in maintaining high HDL levels in these seals.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2022)
Article
Marine & Freshwater Biology
Richard Condit, Roxanne S. Beltran, Patrick W. Robinson, Daniel E. Crocker, Daniel P. Costa
Summary: Northern elephant seals migrate long distances to breeding beaches to raise pups during a brief period. The timing of their arrival is crucial, with early arrival wasting foraging time and late arrival causing parturition failure. Despite traveling thousands of kilometers while pregnant, female elephant seals are able to time their arrival within days, maintaining a precise annual birth cycle for many years consecutively.
MARINE MAMMAL SCIENCE
(2022)
Article
Multidisciplinary Sciences
Richard Condit, Sarah G. Allen, Daniel P. Costa, Sarah Codde, P. Dawn Goley, Burney J. Le Boeuf, Mark S. Lowry, Patricia Morris
Summary: The study aimed to develop a method for estimating animal populations using a single site, particularly for asynchronous species. By testing the model at multiple colonies and demonstrating its capability to account for variations in animal presence over time, it provides a way to estimate total population throughout a season. This method can be applied to various seasonal species with asynchronous breeding, offering an efficient way to estimate population sizes with minimal time and resources.
Article
Multidisciplinary Sciences
Sarah S. Kienle, Ari S. Friedlaender, Daniel E. Crocker, Rita S. Mehta, Daniel P. Costa
Summary: This study investigates the sex-specific foraging strategies of northern elephant seals, with males as benthic predators and females as deep-diving predators. Males have a higher mortality rate compared to females. The foraging strategies and trade-offs between foraging rewards and mortality risk are related to energy demands and life-history strategies.
ROYAL SOCIETY OPEN SCIENCE
(2022)
Article
Multidisciplinary Sciences
Taiki Adachi, Yasuhiko Naito, Patrick W. Robinson, Daniel P. Costa, Luis A. Huckstadt, Rachel R. Holser, Wataru Iwasaki, Akinori Takahashi
Summary: This study reveals the significance of whiskers in the natural foraging behavior of free-ranging elephant seals. The whiskers help the seals sense prey in the deep ocean, supplementing their visual prey detection abilities. This finding highlights the adaptive alternative to echolocation in deep-diving mammals and demonstrates the importance of incorporating multiple sensory systems in studying predator foraging success.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Oceanography
Rachel R. Holser, Theresa R. Keates, Daniel P. Costa, Christopher A. Edwards
Summary: Marine heatwaves are prolonged warm water events that are increasing in frequency and magnitude due to rising global temperatures. The Northeast Pacific Blob, an unusually widespread marine heatwave, affected ecosystems across the Northeast Pacific and was found to be influenced by both surface warming and northward advection of warm, salty water. Analysis of temperature and salinity data collected by northern elephant seals showed significant warm anomalies throughout the water column and peak warming in late 2015, contributing to our understanding of the thermal content and structure of the Blob.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Marine & Freshwater Biology
Renato Borras-Chavez, Michael E. Goebel, Stella Villegas-Amtmann, Luis A. Huckstadt, Carla Rivera-Rebella, Daniel P. Costa, Jose M. Farina, Francisco Bozinovic
Summary: The study investigates the behavioral adjustments of lactating Antarctic fur seal females by comparing their foraging behavior with that of nonlactating females. The results show that lactating females have shorter foraging trips and spend less time onshore compared to nonlactating females, likely to optimize offspring provisioning. Lactating females also exhibit a reduced mean time per dive but a greater percentage of time per trip spent diving.
MARINE MAMMAL SCIENCE
(2023)
Article
Biodiversity Conservation
Logan J. Pallin, Nick M. Kellar, Debbie Steel, Natalia Botero-Acosta, C. Scott Baker, Jack A. Conroy, Daniel P. Costa, Chris M. Johnson, David W. Johnston, Ross C. Nichols, Doug P. Nowacek, Andrew J. Read, Oksana Savenko, Oscar M. Schofield, Sharon E. Stammerjohn, Deborah K. Steinberg, Ari S. Friedlaender
Summary: By studying the relationship between humpback whale pregnancy rates and krill availability as well as ice cover fluctuations, it was found that the limitation of krill resources has an impact on whale reproductive rates, contrary to the previous krill surplus hypothesis. This suggests that the population growth of humpback whales in the Antarctic may be limited by prey availability.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Virology
Morgan Furlong, Andrew M. Adamu, Andrew Hoskins, Tanya L. Russell, Bruce Gummow, Maryam Golchin, Roslyn I. Hickson, Paul F. Horwood
Summary: Mathematical and geospatial mapping techniques were used to estimate the risk of Japanese encephalitis virus transmission in coastal and inland regions of Australia. Increased surveillance of waterbirds, feral pigs, and mosquito populations is recommended in areas with human and domestic pig populations.
Article
Ecology
Taiki Adachi, Philip Lovell, James Turnbull, Mike A. Fedak, Baptiste Picard, Christophe Guinet, Martin Biuw, Theresa R. Keates, Rachel R. Holser, Daniel P. Costa, Daniel E. Crocker, Patrick J. O. Miller
Summary: Researchers have developed a novel satellite-linked data logger that can calculate real-time changes in body condition of marine mammals, specifically lipid stores. This method is applicable to a wide array of diving animals, allowing for assessment of body condition in a broad range of species. This advancement has the potential to improve marine biology research by directly measuring changes in body condition in relation to foraging effort, habitat, ecological factors, and anthropogenic stressors.
METHODS IN ECOLOGY AND EVOLUTION
(2023)
Article
Physiology
Allison D. Northey, Rachel R. Holser, Garrett T. Shipway, Daniel P. Costa, Daniel E. Crocker
Summary: By injecting ACTH into northern elephant seals, researchers found that there were differences in stress responses during the early and late stages of their molting period. Extended, high-energy fasting increased the release of cortisol and aldosterone, impacting metabolism and immune function. These findings emphasize the importance of considering life-history context when assessing the impacts of anthropogenic stressors on wildlife.
AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY, INTEGRATIVE AND COMPARATIVE PHYSIOLOGY
(2023)
Review
Biology
Daniel P. Costa, Arina B. Favilla
Summary: Comparative physiology has provided insights into the physiological adaptations of organisms. Aquatic air-breathing vertebrates, with their diving behavior, represent a unique study system for understanding the interplay between ecology, physiology, and behavior. This review examines the history of research on diving physiology and behavior, and highlights the importance of considering factors such as aerobic diving limit, body size, oxygen stores, prey distribution, and metabolism.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2023)
Article
Biology
Ana M. Valenzuela-Toro, Rita Mehta, Nicholas D. Pyenson, Daniel P. Costa, Paul L. Koch
Summary: Body size and feeding morphology play a crucial role in how animals organize themselves within communities. In this study, we investigated the relationships between sex, body size, skull morphology, and foraging behavior in sympatric otariids from the eastern North Pacific Ocean. We found significant differences in size, skull morphology, and foraging behavior among species and sexes, with sea lions showing higher foraging values than fur seals, and males having higher values than females. Additionally, there was a community-wide correlation between skull length and foraging, indicating a preference for nearshore habitats and higher trophic level prey among larger individuals.