Article
Environmental Sciences
Gwyneth A. MacMillan, Marc Amyot, Pierre-Yves Daoust, Melanie Lemire
Summary: In this study, we measured trace elements and mercury distribution in grey seals from the Gulf of St. Lawrence, Canada, and found a bioaccumulation pattern in different age groups. The concentrations of elements were lower in the muscles and livers of young-of-the-year seals compared to older ones feeding at sea. There were no significant sex-specific differences, but some elements showed higher concentrations in male seals.
Article
Environmental Sciences
David G. Watson, Patrick P. Pomeroy, Malcolm W. Kennedy
Summary: Mothers of the Atlantic grey seal lactate for about 20 days, leaving their pups unattended and unfed for up to another 40 days after weaning. Metabolomic analysis of the seals' milk reveals continuous changes in key metabolites from birth to weaning, indicating a transition from carbohydrate to fat-based energy metabolism in pups and establishment of gut microbiomes for post-weaning development and fasting.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Marine & Freshwater Biology
Mette K. Schionning, Martha Gosch, Eileen Dillane, Michelle Cronin, Mark J. Jessopp
Summary: Recovery of gray seal populations in the eastern Atlantic has resulted in increased interactions with fisheries, with fishermen estimating high rates of predation on salmonids and monkfish in Ireland. This study used genetic testing to show that gray seals in Ireland consume monkfish and salmonids, with varying occurrence rates depending on season and region. Traditional hard part analysis failed to detect these species, highlighting the importance of genetic methods in studying predator-prey interactions.
MARINE MAMMAL SCIENCE
(2021)
Article
Fisheries
Esa Lehtonen, Roope Lehmonen, Joel Kostensalo, Mika Kurkilahti, Petri Suuronen
Summary: Testing the feasibility and effectiveness of acoustic deterrent devices (ADDs) in Baltic salmon trap-net fisheries, this study found that using ADDs can significantly reduce seal-induced catch losses, with an average increase of 64% in salmon catches over a two-year period. The research suggests that ADD is a useful and economically viable tool for reducing seal-induced catch losses in trap-net fisheries.
FISHERIES RESEARCH
(2022)
Article
Marine & Freshwater Biology
Cornelia E. den Heyer, W. Don Bowen, Julian Dale, Jean-Francois Gosselin, Michael O. Hammill, David W. Johnston, Shelley L. C. Lang, Kimberly T. Murray, Garry B. Stenson, Stephanie A. Wood
Summary: The study found that the northwest Atlantic subspecies of gray seal has been increasing over the past half century and has reestablished breeding colonies, with Sable Island being the largest producer of pups. Regional differences in pup production trends are evident, with Sable Island's growth rate slowing down while newer breeding colonies in southwest Nova Scotia and the northeastern United States are rapidly increasing.
MARINE MAMMAL SCIENCE
(2021)
Article
Marine & Freshwater Biology
Sydney J. J. Allen, W. Don Bowen, Cornelia E. den Heyer
Summary: The study found that gray seal females' selection of birth-site habitat is influenced by both their age and parity, with younger and less experienced females preferring beach habitat, while older and more experienced females are more commonly found inland and on vegetated dunes. Longitudinal data also revealed moderate repeatability of birth-site habitat selection, with pups born in inland sand habitat that did not flood averaging 1.5 kg heavier at weaning than those born on tidally influenced beach habitat. Overall, birth-site habitat selection was associated with small effects on offspring body mass at weaning.
MARINE MAMMAL SCIENCE
(2022)
Article
Ecology
Neil M. Burns, Charlotte R. Hopkins, Maria Martina Quaggiotto, Dominic J. McCafferty, David M. Bailey
Summary: Decomposing organic matter is crucial for energy and nutrient recycling in ecosystems, but the role of animal carrion biomass in ecosystem functioning is poorly understood. This study examined a grey seal breeding colony on the Isle of May in Scotland and found that they contribute significantly to the carrion biomass available in the surrounding marine systems.
MARINE ECOLOGY PROGRESS SERIES
(2022)
Article
Environmental Sciences
Delphine B. H. Chabanne, Simon J. Allen, William Bruce Sherwin, Hugh Finn, Michael Krutzen
Summary: The study conducted on Indo-Pacific bottlenose dolphins in Perth found four behavioral communities with similar genetic structures but small differentiation due to related individuals within communities. The high levels of contemporary migration and related individuals among communities suggest a panmictic genetic population with continuous gene flow. Despite genetic similarity, each social community should be considered a distinct ecological unit for conservation due to exposure to different threats and occurrence in different habitats.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Hannah M. E. Wyles, Lars Boehme, Debbie J. F. Russell, Matt I. D. Carter
Summary: Understanding how marine predators find patchily distributed prey resources in a dynamic environment is crucial for ecosystem-level conservation management. In this study, the influence of geomorphology on the habitat use of grey seals was examined using GPS tracking data, and it was found that certain types of seabed features had a significant impact on the transition from travelling to foraging behavior.
FRONTIERS IN MARINE SCIENCE
(2022)
Review
Ecology
Arkadiusz Dziech
Summary: The development of genetic tools in recent decades has allowed for more detailed analysis and understanding of species hybridization, with microsatellites and single nucleotide polymorphisms proving to be reliable markers for identifying mixed individuals and their actual proportions in a population.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2021)
Article
Ecology
Keith M. Hernandez, Wendy Blay Puryear, Jonathan A. Runstadler, Michael J. Polito
Summary: Analysis of gray seal population in coastal Massachusetts over 4 years showed that maternal foraging ecology during pregnancy has a significant impact on offspring condition. Despite fluctuations in environmental conditions and prey availability, there was little interannual variability in female foraging ecology at the population level.
MARINE ECOLOGY PROGRESS SERIES
(2021)
Article
Zoology
Michelle N. Dufault, Zachary H. Olson, Dominique M. Mellone, Kelly R. Flanders, Kathryn A. Ono
Summary: By analyzing prey DNA in seal scat, researchers found that flatfish presence in the diet of gray seals was higher than previously estimated, indicating a potential underestimation of the importance of flatfish in gray seal diet in previous studies.
CANADIAN JOURNAL OF ZOOLOGY
(2021)
Article
Multidisciplinary Sciences
Sean D. Twiss, Naomi Brannan, Courtney R. Shuert, Amanda M. Bishop, Patrick. P. Pomeroy, Simon Moss
Summary: Measures of heart rate variability have been used to study temperament and reactivity to stress in wild animals. A new heart rate monitor allows for precise measurement of inter beat intervals in gray seals, with results showing high correspondence with traditional ECG recordings. Artifact correction and individual activity were found to be major sources of anomalous data, leading to the establishment of stringent filtering procedures to ensure accurate estimates of resting HRV.
Article
Marine & Freshwater Biology
Helen S. Chadwick, James E. F. Barnett, Abby Crosby, Anthea Hawtrey-Collier, Victoria J. Hobson, Lucy C. M. Omeyer, Ruth Williams, Brendan J. Godley
Summary: Changes in grey seal strandings in Cornwall and the Isles of Scilly over a 21-year period indicate a significant increase in abundance. The observed seasonality of strandings coincided with important life phases, and most strandings occurred on the north coast of Cornwall. Long-term citizen science data proved valuable for assessing the distribution and abundance of marine top predators.
JOURNAL OF THE MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM
(2023)
Article
Zoology
Christina M. McCosker, Zachary H. Olson, Kathryn A. Ono
Summary: This study compares two non-invasive methods, metabarcoding and hard parts analysis, to study the diet of grey seals. The results show that metabarcoding detects a greater diversity and frequency of prey, while hard parts analysis more frequently detects specific prey. Combining both methods increased the number of prey detections, with a total of 32 prey taxa identified.
CANADIAN JOURNAL OF ZOOLOGY
(2023)
Article
Ecology
Sophie Smout, Ruth King, Patrick Pomeroy
JOURNAL OF ANIMAL ECOLOGY
(2020)
Article
Marine & Freshwater Biology
Izzy Langley, Tobias Rosas da Costa Oliver, Lex Hiby, Thomas B. Stringell, Ceri W. Morris, Oliver O'Cadhla, Lisa Morgan, Kate Lock, Sarah Perry, Stephen Westcott, Dave Boyle, Birgitta Buche, Edward M. Stubbings, Rebecca M. Boys, Holly Self, Charlie Lindenbaum, Powell Strong, Mick Baines, Patrick P. Pomeroy
Article
Multidisciplinary Sciences
David G. Watson, Patrick P. Pomeroy, Naser F. Al-Tannak, Malcolm W. Kennedy
SCIENTIFIC REPORTS
(2020)
Article
Multidisciplinary Sciences
Sean D. Twiss, Courtney R. Shuert, Naomi Brannan, Amanda M. Bishop, Patrick P. Pomeroy
SCIENTIFIC REPORTS
(2020)
Article
Ecology
Courtney R. Shuert, Lewis G. Halsey, Patrick P. Pomeroy, Sean D. Twiss
JOURNAL OF ANIMAL ECOLOGY
(2020)
Article
Environmental Sciences
France Damseaux, Ursula Siebert, Patrick Pomeroy, Gilles Lepoint, Krishna Das
Summary: The study focused on ecological niche segregation between grey seals and harbour seals in the North Sea, revealing spatial and resource partitioning, more selective diet of grey seals, and potential sharing of food resources along the German coasts. The multi-tracer approach provided a robust discrimination among diet resources and spatial foraging distributions of the seals.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
David G. Watson, Patrick P. Pomeroy, Malcolm W. Kennedy
Summary: Mothers of the Atlantic grey seal lactate for about 20 days, leaving their pups unattended and unfed for up to another 40 days after weaning. Metabolomic analysis of the seals' milk reveals continuous changes in key metabolites from birth to weaning, indicating a transition from carbohydrate to fat-based energy metabolism in pups and establishment of gut microbiomes for post-weaning development and fasting.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Biology
Kagari Aoki, Saana Isojunno, Charlotte Bellot, Takashi Iwata, Joanna Kershaw, Yu Akiyama, Lucia M. Martin Lopez, Christian Ramp, Martin Biuw, Rene Swift, Paul J. Wensveen, Patrick Pomeroy, Tomoko Narazaki, Ailsa Hall, Katsufumi Sato, Patrick J. O. Miller
Summary: This study cross-validated two independent methods, animal-borne tags and aerial photogrammetry, to estimate the body condition of humpback whales in Canada and Norway, showing lower tissue body density in pregnant females and higher in lactating females. Whales in Norway exhibited more negative buoyancy during the early feeding season compared to Canada, possibly due to longer migration distances. Despite a decrease in tissue body density over the feeding season, whales remained negatively buoyant in the late feeding season.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2021)
Article
Ecology
Hannah Worthington, Ruth King, Rachel McCrea, Sophie Smout, Patrick Pomeroy
Summary: Long-term capture-recapture studies provide insight into the population dynamics of long-lived species by examining individual maturation, recruitment into breeding population, and changes over time. The study on female gray seals shows variability in maturation rates and recruitment ages, highlighting the importance of understanding these processes for effective population management strategies. Age-structured capture-recapture models can explicitly relate recruitment and demographic parameters to age and time, providing a more realistic recruitment profile for population models.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2021)
Article
Multidisciplinary Sciences
Sean D. Twiss, Naomi Brannan, Courtney R. Shuert, Amanda M. Bishop, Patrick. P. Pomeroy, Simon Moss
Summary: Measures of heart rate variability have been used to study temperament and reactivity to stress in wild animals. A new heart rate monitor allows for precise measurement of inter beat intervals in gray seals, with results showing high correspondence with traditional ECG recordings. Artifact correction and individual activity were found to be major sources of anomalous data, leading to the establishment of stringent filtering procedures to ensure accurate estimates of resting HRV.
Article
Ecology
Suzanne McGill, Richard J. S. Burchmore, Patrick P. Pomeroy, Malcolm W. Kennedy
Summary: A study found that neonates of true, phocid seals have significantly lower levels of serum immunoglobulins and acute phase proteins compared to their mothers. This difference in early life immune protection raises questions about the mechanisms that protect these neonates and the adaptive value of their seeming vulnerability.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2022)
Article
Environmental Sciences
Suzanne McGill, Richard J. S. Burchmore, Patrick P. Pomeroy, Malcolm W. Kennedy
Summary: Phocid seals have short lactations relative to body mass, with an unrivaled rate and extent of transfer of adipose stores from mother to offspring. Proteomic analysis of sera from Atlantic grey seals shows a mirror image flux of lipids between mothers and pups, reflected in an inverse relationship in the specialized proteins in their blood for fat transportation.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Cell Biology
Holly C. Armstrong, Debbie J. F. Russell, Simon E. W. Moss, Paddy Pomeroy, Kimberley A. Bennett
Summary: Life-history-oxidative stress theory predicts that elevated energy costs during reproduction reduce allocation to defences and increase cellular stress, with fitness consequences, particularly when resources are limited. Grey seals, as capital breeders, were used as a natural system to test this theory. The study found that foraging females experienced lower oxidative stress and higher cellular defences compared to lactating mothers, suggesting that resources were diverted to pup rearing rather than blubber tissue damage. The cellular stress and defences during lactation affected pup weaning mass and survival probability. These results support the life-history-oxidative stress hypothesis and highlight the vulnerability of mothers during lactation to environmental factors.
CELL STRESS & CHAPERONES
(2023)
Article
Behavioral Sciences
Zoe L. Fraser, Ross M. Culloch, Sean D. Twiss