Article
Oceanography
Yves Cherel, Colette Trouve, Paco Bustamante
Summary: The diet of the light-mantled sooty albatross Phoebetria palpebrata was studied for the first time at the Kerguelen Islands in the subantarctic region by analyzing the beaks from regurgitated boluses. The study identified 22 taxa, including four dominant squid species endemic to the Southern Ocean. The results showed that different albatross species have species-specific foraging grounds, and the cephalopod prey of Kerguelen albatrosses highlighted the abundance and importance of certain squid species in the pelagic ecosystem of the southern Indian Ocean.
DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS
(2023)
Article
Environmental Sciences
Lucien Besnard, Gael Le Croizier, Felipe Galvan-Magana, David Point, Edouard Kraffe, James Ketchum, Raul Octavio Martinez Rincon, Gauthier Schaal
Summary: The decline of shark populations in the world ocean has unpredictable effects on ecosystem structure and function, necessitating new ecological information for a better understanding of the role of sharks in their habitats. Research has found that many shark species primarily forage in the mesopelagic area, but the extent to which different pelagic sharks rely on this habitat has been overlooked. By using mercury stable isotopes in the muscle of pelagic sharks, it is possible to reveal their food partitioning and the relationship between foraging depth and resource competition.
ENVIRONMENTAL POLLUTION
(2021)
Article
Engineering, Environmental
Ryan F. Lepak, Sarah E. Janssen, Jacob M. Ogorek, Casey B. Dillman, Joel C. Hoffman, Michael T. Tate, Peter B. McIntyre
Summary: This study tested the stability of mercury concentrations and stable isotope ratios in preserved fish under museum preservation practices. Loss of unidentified constituents during preservation led to increased mercury concentrations in fish muscle. Low-mercury fish were susceptible to contamination with inorganic mercury when intentionally spiked or passively leached from contaminated wild fish. However, the conservative nature of methylmercury allowed for quantitative correction of the contamination. The findings suggest the potential use of preserved fish from museums for generating spatiotemporal baselines for the Minamata Convention on Mercury, with precautions recommended for maximizing inference strength.
ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Frerk Poppelmeier, Marcus Gutjahr, Patrick Blaser, Hartmut Schulz, Finn Suefke, Joerg Lippold
Summary: Research has shown that deep ocean carbon storage increased with limited variations in the past 100,000 years, with northern-sourced water dominating throughout. During Marine Isotope Stage 4, proportions of northern-sourced water even increased by approximately 15% in the Equatorial and Northeast Atlantic, questioning the idea that cold climates promote the expansion of southern-sourced water.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Ornithology
William F. Mills, Rona A. R. McGill, Yves Cherel, Stephen C. Votier, Richard A. Phillips
Summary: The non-breeding period is crucial for the restoration of body condition and self-maintenance in Grey-headed Albatrosses. Using stable isotope values, this study found that individuals foraged across a range of oceanic habitats, with males foraging at higher latitudes and higher trophic levels compared to females. Repeatability among feathers of the same individual was moderate in delta C-13 and low in delta N-15.
Review
Oceanography
Raquel Garcia-Vernet, Asuncion Borrell, Gisli Vikingsson, Sverrir D. Halldorsson, Alex Aguilar
Summary: The highly productive waters off Iceland are an important feeding ground for baleen whales, and during the summer feeding season, five balaenopterid species coexist by segregating their food sources to avoid competition, except for blue and fin whales, they all show clear ecological niche partitioning.
PROGRESS IN OCEANOGRAPHY
(2021)
Article
Ecology
Cody K. Porter, Jimena Golcher-Benavides, Craig W. Benkman
Summary: Dietary partitioning plays a central role in biological communities and its extent varies over time, possibly due to food availability and seasonality. The study found that dietary partitioning is greatest when food abundance is low, implying competition for limited food resources. The extent of dietary partitioning in birds and mammals is also related to seasonal changes in primary productivity.
Article
Environmental Sciences
Alessandra Cani, Luis Cardona, Meica Valdivia, Enrique M. Gonzalez, Massimiliano Drago
Summary: By analyzing the sulfur (δS-34) and oxygen (δO-18) isotopic ratios in bone, the study reveals the habitat use of seven marine mammal species inhabiting the Rio de la Plata estuary and the adjacent Atlantic Ocean. The integration of different stable isotope ratios helps to better delineate habitat partitioning between marine mammals in this complex ecosystem, providing valuable insights into their role in the ecosystem.
ESTUARIES AND COASTS
(2023)
Article
Multidisciplinary Sciences
June Eggebo, Jasmin Gross, Susan Bengtson Nash
Summary: This study compared the carbon and nitrogen isotopic values of blubber and skin tissues of Southern Hemisphere humpback whales, revealing significant differences between the two tissues. It highlights the need for method validation and standardization in the application of these approaches, advancing the methodological aspects of cetacean dietary analysis. This is of elevated importance in the context of rapidly changing ocean ecosystems.
Article
Marine & Freshwater Biology
J. Farber Lorda, M. Murcia-Riano
Summary: The study evaluated sympatric euphausiid species from the eastern tropical North Pacific and the California Current for stable isotopes, elemental composition, and lipid content, finding geographic patterns and species-level trophic niche partitioning. Higher trophic positions were observed in tropical species compared to California Current species, with significant differences in trophic positions among species. Thysanoessa spinifera exhibited higher values in isotopic signal, elemental composition, and total lipid content, while tropical species had lower individual carbon due to smaller sizes and lower lipid content. The differences between species from the two areas are likely related to differences in latitude, temperature, and trophic conditions.
Article
Ecology
Philip Matich, Joseph J. Bizzarro, Oliver N. Shipley
Summary: This article discusses the increasing importance of understanding animal resource use patterns in predicting biological resilience amidst growing concerns about anthropogenic and natural disturbance. While stable isotope analysis has been widely used in ecological studies to describe trophic interactions, its inherent limitations and inappropriate synonymizing may lead to misleading ecological inferences.
ECOLOGICAL APPLICATIONS
(2021)
Article
Geochemistry & Geophysics
Brandi N. Revels, Jorg Rickli, Candido A. Moura, Derek Vance
Summary: The study found that dissolved load dominates over particulate load for molybdenum in Amazonian rivers, and molybdenum isotope data show systematic variability between river types and seasons. Variations in molybdenum isotopes across tributaries and seasons are best explained by processes related to weathering regime, indicating significant temporal variability in the riverine source of molybdenum to the oceans controlled by tectonic and climate impacts.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Ecology
Joshua T. Bauld, Katharine A. Abernethy, Jason Newton, David Lehmann, Isabel L. Jones, Luc F. Bussiere
Summary: Classic evolutionary theory suggests that sexual dimorphism evolves primarily through sexual and fecundity selection. However, recent research indicates that resource competition may also contribute to the evolution of sexual dimorphism through ecological character displacement between sexes. This study conducted a meta-analysis to examine the association between isotopic divergence and body size dimorphism, and found modest but significant positive associations, particularly when there was a greater ecological opportunity for dietary divergence between sexes.
ECOLOGY AND EVOLUTION
(2022)
Article
Ecology
Priscilla M. Wehi, Karyne M. Rogers, Tim Jowett, Amandine J. M. Sabadel
Summary: This study investigates the feather stable isotope values in kea populations in New Zealand and finds a lower trophic position in modern kea populations, reflecting reduced lowland habitat and a mixed diet with more plant material. The study also identifies size and sex as factors influencing trophic values in kea, with larger birds more likely to have a high protein diet. The findings suggest potential changes in ecological networks and sexually dimorphic feeding patterns within kea species.
JOURNAL OF ANIMAL ECOLOGY
(2023)
Article
Environmental Sciences
Adelaide V. Dedden, Tracey L. Rogers
Summary: This study investigates the links between whale feeding patterns and climate cycles. The results show that variability in stable isotope values within whale baleen is associated with shifts in climate cycles, suggesting changes in feeding patterns due to resource availability. However, these relationships vary depending on the oceanic region in which the whales feed.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Ornithology
Jade Lopez, Natacha Nikolic, Martin Riethmuller, Jerome Dubos, Patrick Pinet, Patxi Souharce, Francois-Xavier Couzi, Matthieu Le Corre, Audrey Jaeger, Laurence Humeau
Summary: The critically endangered Mascarene Petrel has a high genetic diversity with a contemporary effective population size of approximately 1211 individuals, and a probable bottleneck around 10 000 generations ago. Further studies are needed to evaluate its evolutionary potential.
Article
Multidisciplinary Sciences
Martin Beal, Maria P. Dias, Richard A. Phillips, Steffen Oppel, Carolina Hazin, Elizabeth J. Pearmain, Josh Adams, David J. Anderson, Michelle Antolos, Javier A. Arata, Jose Manuel Arcos, John P. Y. Arnould, Jill Awkerman, Elizabeth Bell, Mike Bell, Mark Carey, Ryan Carle, Thomas A. Clay, Jaimie Cleeland, Valentina Colodro, Melinda Conners, Marta Cruz-Flores, Richard Cuthbert, Karine Delord, Lorna Deppe, Ben J. Dilley, Herculano Dinis, Graeme Elliott, Fernanda De Felipe, Jonathan Felis, Manuela G. Forero, Amanda Freeman, Akira Fukuda, Jacob Gonzalez-Solis, Jose Pedro Granadeiro, April Hedd, Peter Hodum, Jose Manuel Igual, Audrey Jaeger, Todd J. Landers, Matthieu Le Corre, Azwianewi Makhado, Benjamin Metzger, Teresa Militao, William A. Montevecchi, Virginia Morera-Pujol, Leia Navarro-Herrero, Deon Nel, David Nicholls, Daniel Oro, Ridha Ouni, Kiyoaki Ozaki, Flavio Quintana, Raul Ramos, Tim Reid, Jose Manuel Reyes-Gonzalez, Christopher Robertson, Graham Robertson, Mohamed Salah Romdhane, Peter G. Ryan, Paul Sagar, Fumio Sato, Stefan Schoombie, R. Paul Scofield, Scott A. Shaffer, Nirmal Jivan Shah, Kim L. Stevens, Christopher Surman, Robert M. Suryan, Akinori Takahashi, Vikash Tatayah, Graeme Taylor, David R. Thompson, Leigh Torres, Kath Walker, Ross Wanless, Susan M. Waugh, Henri Weimerskirch, Takashi Yamamoto, Zuzana Zajkova, Laura Zango, Paulo Catry
Summary: This study combines tracking data and breeding population size data to estimate the relative importance of national jurisdictions and high seas areas for migratory marine species, highlighting the stake each country has in managing biodiversity in international waters. The study quantifies the links between national populations of threatened seabirds and the regional fisheries management organizations (RFMOs) regulating fishing in the high seas, providing valuable information for the conservation and management of migratory species in the marine realm.
Article
Marine & Freshwater Biology
I. A. Micklem, M. Connan, N. Stander, C. D. McQuaid
Summary: This study investigated the influence of consumer ontogeny on stable isotope ratios and trophic discrimination factors (TDFs) in African penguins. The results showed that age class affected the stable isotope compositions of whole blood and red blood cells, with chicks and fledglings exhibiting lower delta C-13 and delta N-15 values than juveniles and adults. Plasma, however, demonstrated no effect of ontogeny.
Article
Environmental Sciences
Maelle Connan, Vonica Perold, Ben J. Dilley, Christophe Barbraud, Yves Cherel, Peter G. Ryan
Summary: Marine litter has become a global issue, with 'garbage patches' documented in all ocean gyres. A study conducted in the rarely investigated south-west Indian Ocean in 2019-2020 found an accumulation of litter and called for more research in the area.
MARINE POLLUTION BULLETIN
(2021)
Article
Multidisciplinary Sciences
Marie-Lazarine Poulle, Matthieu Le Corre, Matthieu Bastien, Elsa Gedda, Chris Feare, Audrey Jaeger, Christine Larose, Nirmal Shah, Nina Voogt, Byron Gopper, Erwan Lagadec, Gerard Rocamora, Regine Geers, Dominique Aubert, Isabelle Villena, Camille Lebarbenchon
Summary: The study suggests that pelagic species in the ocean may be exposed to Toxoplasma gondii oocysts through marine currents and fish. Antibodies against T. gondii were detected in various seabird species, except for the great frigatebird.
Article
Marine & Freshwater Biology
D. Z. Keys, F. Orgeret, M. Le Corre, A. Jaeger, P. A. Pistorius
Summary: This study tracked Wedge-Tailed Shearwaters from Reunion Island and found that they use different foraging tactics during incubation and chick rearing periods, without a strong preference for specific environmental conditions. The research further highlights the importance of 'hotspots' for marine species threatened by anthropogenic pressures.
Article
Biodiversity Conservation
S. Schoombie, M. Connan, B. J. Dilley, D. Davies, A. B. Makhado, P. G. Ryan
Summary: Sooty Albatrosses are endangered birds that breed biennially on sub-Antarctic islands, with successful breeders spending at least 15 months at sea before returning to breeding grounds. During their non-breeding periods, adult Sooty Albatrosses primarily inhabit international waters in the southern Indian Ocean, dividing their time between sub-tropical and sub-Antarctic regions.
Article
Environmental Sciences
Anne-Sophie Bonnet-Lebrun, Maria P. Dias, Richard A. Phillips, Jose P. Granadeiro, M. de L. Brooke, Olivier Chastel, Thomas A. Clay, Annette L. Fayet, Olivier Gilg, Jacob Gonzalez-Solis, Tim Guilford, Sveinn A. Hanssen, April Hedd, Audrey Jaeger, Johannes Krietsch, Johannes Lang, Matthieu Le Corre, Teresa Militao, Borge Moe, William A. Montevecchi, Hans-Ulrich Peter, Patrick Pinet, Matt J. Rayner, Tim Reid, Jose Manuel Reyes-Gonzalez, Peter G. Ryan, Paul M. Sagar, Niels M. Schmidt, David R. Thompson, Rob van Bemmelen, Yutaka Watanuki, Henri Weimerskirch, Takashi Yamamoto, Paulo Catry
Summary: The study found that during the non-breeding season, most seabird species increase their time in flight during migration, and that some nocturnal species spent more time flying during the day, while diurnal species did the opposite.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Marine & Freshwater Biology
L. Gauchet, A. Jaeger, D. Gremillet
Summary: This study used facial infrared thermography to estimate the body temperature of red-footed boobies in their natural environment. The researchers found linear relationships between surface temperatures in different facial regions and the internal body temperatures of the birds. At the individual level, the maximum facial temperatures at the corner of the bill and the internal cantus of the eye were the most accurate indicators of internal temperature. At the species level, the minimal and mean temperatures of the eyeballs provided the best estimates. Factors such as wind speed, ambient temperature, sun exposure, and shooting distance also influenced the bird's facial surface temperatures.
Article
Biodiversity Conservation
M. N. Bester, M. Connan
Summary: Southern elephant seals play a crucial role in the food chain in the Southern Ocean, predominantly consuming cephalopods. Limited knowledge exists on their diet at Prince Edward Islands in the sub-Antarctic, with stomach contents analysis revealing a lack of fish remains.
Article
Zoology
Fannie W. Shabangu, G. J. Greg Hofmeyr, Rachel Probert, Maelle Connan, Corrine A. Buhrmann, Tess Gridley
Summary: This study investigated the in-air acoustic repertoire and associated behavior of crabeater seals. The results revealed that hisses were the most common sound, occurring during heightened arousal states and interactions. Moan calls were detected from only two of the three seals, and the female seal switched to producing croaks during rehabilitation. The findings suggest that the in-air acoustic repertoire and associated behavior of these seals are dynamic and context-dependent.
BIOACOUSTICS-THE INTERNATIONAL JOURNAL OF ANIMAL SOUND AND ITS RECORDING
(2023)
Article
Anatomy & Morphology
Liezl E. Pretorius, Marthan N. Bester, Maelle Connan, G. J. Greg Hofmeyr
Summary: This study examines the use of external measurements of canine teeth to distinguish between species, determine sex, age, and island of origin in fur seals. The results show that external measurements can be used to differentiate species and sex, but distinguishing females and determining island of origin is more challenging.
JOURNAL OF MORPHOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Helena Teixeira, Matthieu Le Corre, Audrey Jaeger, Arthur Choeur, Merlene Saunier, Francois-Xavier Couzi, Vikash Tatayah, Nirmal Jivan Shah, Malcolm A. C. Nicoll, Nais Avargues, Laurence Humeau
Summary: This study developed 25 new microsatellite loci, providing valuable tools for population genetic studies in shearwaters. The results showed the importance of these loci for designing effective conservation and management plans.
MOLECULAR BIOLOGY REPORTS
(2022)
Article
Ornithology
Maelle Connan, Stefan Schoombie, Janine Schoombie, Ben Dilley, Peter G. Ryan
Summary: Nocturnal burrow-nesting seabirds, such as the Common Diving Petrel, are challenging to study due to their remote habitat. However, recent research on the sub-Antarctic Prince Edward Islands has revealed the recolonization of Common Diving Petrels following the eradication of introduced cats. The breeding phenology and success of the birds were studied, with observations of nesting, hatching, and fledging patterns.
Article
Multidisciplinary Sciences
Jeffrey N. Zeyl, Edward P. Snelling, Maelle Connan, Mathieu Basille, Thomas A. Clay, Rocio Joo, Samantha C. Patrick, Richard A. Phillips, Pierre A. Pistorius, Peter G. Ryan, Albert Snyman, Susana Clusella-Trullas
Summary: Birds exhibit wide variation in their use of aquatic environments, and some diving birds have the ability to detect and respond to sound underwater, possibly due to modifications in their ear structure. This study measured a suite of morphological traits related to aerial and aquatic hearing in bird ears and found significant differences in ear structure between diving birds and terrestrial species. These results confirm adaptations of the middle ear to aquatic lifestyles in birds.
SCIENTIFIC REPORTS
(2022)