Jean-Baptiste Thiebot

French National Centre for Scientific Research | CNRS

When facing changes in the available forage fish composition and distribution, seabirds are expected to respond by switching their prey species and/or adjusting their key foraging areas. We studied chick-rearing Rhinoceros Auklets Cerorhinca monocerata at Teuri Island, Japan, across three successive years. We examined inter-annual and seasonal chan...

The child-like question of why birds sing in the morning is difficult to answer, especially in polar regions. There, in summer animals live without the time constraints of daylight, and little is known about the rhythmicity of their routines. Moreover, in situ monitoring of animal behavior in remote areas is challenging and rare. Here, we use audio...

Due to its persistence and potential ecological and health impacts, mercury (Hg) is a global pollutant of major concern that may reach high concentrations even in remote polar oceans. In contrast to the Arctic Ocean, studies documenting Hg contamination in the Southern Ocean are spatially restricted and large-scale monitoring is needed. Here, we pr...

Short-tailed shearwaters Ardenna tenuirostris are seasonally abundant consumers in the Southern Ocean, but their diet in this region is debated. Among birds found on vessels at high latitudes (n = 11 live birds and 4 carcasses), at least six had recently ingested Antarctic krill Euphausia superba. Accumulated fresh remains with no flesh attached we...

The at-sea ecology of marine migratory species has been unevenly studied across life-cycle stages, which limits our understanding of how distant marine ecosystems may be connected. The macaroni penguin Eudyptes chrysolophus is the largest avian consumer of marine resources in the world, however no at-sea distribution data are available on this spec...

Since the last Arctic Monitoring and Assessment Programme (AMAP) effort to review biological effects of mercury (Hg) on Arctic biota in 2011 and 2018, there has been a considerable number of new Arctic bird studies. This review article provides contemporary Hg exposure and potential health risk for 36 Arctic seabird and shorebird species, represent...

One direct consequence of Arctic warming is the expansion of navigable portions of the Arctic Ocean. As a result, vessel traffic and the accompanying threats of spills, strikes and disturbance is intensifying throughout the Arctic. In the Bering Sea, these threats to the environment, wildlife and to the people who rely on marine resources for food...

Plastic pollution, and its associated impacts on marine fauna due to chemical contamination, is an area of growing global concern. We analyzed 145 preen gland oil samples from 32 seabird species belonging to 8 families with different foraging habits and life history strategies from around the world for plastic additives and legacy persistent organi...

The expansion of human activities in offshore maritime regions has outpaced the development of scientific knowledge and cooperative governance across these areas beyond national jurisdiction (ABNJ). In this context, current negotiations by the United Nations aim for an international legally-binding instrument to improve governance and sustainable u...

Rapid environmental changes can dramatically and durably affect the animal's foraging behavior. In the Ross Sea (Antarctica), calving of the Nansen Ice Shelf in 2016 opened a newly accessible marine area of 214 km2. In this study, we examined the foraging behavior of Adélie penguins from the nearby Inexpressible Island in December 2018, by tracking...

Anthropogenic marine debris is a threat to marine organisms. Understanding how this debris spatially distributes at sea and may become associated with marine wildlife are key steps to tackle this current issue. Using bird-borne GPS- and video-loggers on 13 black-footed albatrosses Phoebastria nigripes breeding in Torishima, Japan, we examined the d...

MONDRETI, R., DAVIDAR, P., RYAN, P.G., THIEBOT, J.B. & GREMILLET, D. 2020. Seabird and cetacean occurrence in the Bay of Bengal associated with marine productivity and commercial fishing effort. Marine Ornithology 48: 91–101. At-sea observations of seabirds and cetaceans provide essential baseline information about their biogeography and behaviour...

https://arctox.cnrs.fr/en/home/ Mercury (Hg) is a natural trace element found in high concentrations in top predators, including Arctic seabirds. Most current knowledge about Hg concentrations in Arctic seabirds relates to exposure during the summer breeding period when researchers can easily access seabirds at colonies. However, the few studies f...

Recent dramatic reductions of winter sea ice in the northern Bering Sea have raised the possibility that a rapid ecological transformation is underway. It has been hypothesized that with sufficient sea ice loss the cold pool thermal barrier separating the northern and southern Bering Sea would be breached, potentially benefiting piscivorous seabird...

Die-offs of seabirds in Alaska have occurred with increased frequency since 2015. In 2018, on St. Lawrence Island, seabirds were reported washing up dead on beaches starting in late May, peaking in June, and continuing until early August. The cause of death was documented to be starvation, leading to the conclusion that a severe food shortage was t...

Assessing impacts of environmental change on Arctic-breeding seabirds requires a better understanding of their year-round movement and foraging ecology. Here we examined the post-breeding movements and diving behavior of thick-billed (Uria lomvia) and common murres (U. aalge) breeding on St. Lawrence Island, northern Bering Sea, by using geolocator...

The reduced species richness typical of oceanic islands provides an interesting environmental setup to examine in natura the epidemiological dynamics of infectious agents with potential implications for public health and/or conservation. On Amsterdam Island (Indian Ocean), recurrent die-offs of Indian yellow-nosed albatross (Thalassarche carteri) n...

Cyclones are currently increasing in frequency and intensity across the tropical regions, and such changes in cyclonic activity can adversely impact tropical marine ecosystems. To examine the potential effects of these changes on marine migrations, we tracked the annual at-sea distribution of black-naped terns from Okinawa Islands, southwest Japan...

Migratory seabirds experience varying levels of both protection and threats as they travel across marine regions and countries’ jurisdictions. Studying their seasonal distribution provides insights into the full range of exploited habitats and potential gaps in conservation policy existing in the visited areas. Here we used light-based geolocation...

Our paper reports findings on at-sea distributions of both seabirds and cetaceans in the Bay of Bengal. Our study is the first systematic attempt in creating baseline information for this data-poor region. We carried out 39 days of vessel-based observations from 2012 to 2014 over a total linear distance of 4722.3 km. We observed 2697 seabirds of 17...

Oceanic islands with reduced species richness provide an opportunity to investigate the emergence, maintenance and transmission of infectious diseases threatening wildlife. On Amsterdam Island, in the southern Indian Ocean, massive and recurrent mortality of the nestlings of Indian yellow-nosed albatross (Thalassarche carteri) has been attributed t...

The spatial structure of host communities is expected to constrain pathogen spread. However, predators and/or scavengers may connect distant host (sub)populations when foraging. Determining whether some individuals or populations play a prominent role in the spread of pathogens is critical to inform management measures. We explored movements and ep...

There is growing evidence that gelatinous zooplanktonic organisms ("gelata") are regular prey for marine endotherms. Yet the consumption of gelata is intriguing in terms of the energy reward, because endotherms have a high energy demand and the consumption of gelata provides little energy return. In this paper, we take advantage of recent advances...

Spatiotemporal dynamics of ecosystems can challenge the pertinence of Marine Protected Area (MPA) planning. Seasonal environmental changes are extreme in polar regions, however MPA planning in East Antarctica relies mostly on species' summer distribution only. Thirteen Adélie penguins were tracked from Ile des Pétrels (Terre Adélie), and their seas...

Oceanic islands with reduced species richness provide an opportunity to investigate the emergence, maintenance and transmission of infectious diseases threatening wildlife. On Amsterdam Island, in the southern Indian Ocean, massive and recurrent mortality of the nestlings of Indian yellow-nosed albatross (Thalassarche carteri) has been attributed t...

Despite critical implications for disease dynamics and surveillance in wild long-lived species, the immune response after exposure to potentially highly pathogenic bacterial disease agents is still poorly known. Among infectious diseases threatening wild populations, avian cholera, caused by the bacterium Pasteurella multocida, is a major concern....

The Southern Ocean is currently experiencing major environmental changes, including in sea‐ice cover. Such changes strongly influence ecosystem structure and functioning and affect the survival and reproduction of predators such as seabirds. These effects are likely mediated by reduced availability of food resources. As such, seabirds are reliable...

Incidental capture in fisheries (“bycatch”) is a major threat to global marine biodiversity, especially to those species with low fecundity, such as albatrosses. Efforts to reduce bycatch have been undertaken in industrial fisheries, but the scale of seabird interactions with artisanal or small-scale fleets remains largely unknown. The island of To...

Infectious diseases may be particularly critical for the conservation of endangered species. A striking example is the recurrent outbreaks that have been occurring in seabirds on Amsterdam Island for the past 30 years, threatening populations of three Endangered seabird species and of the endemic, Critically Endangered Amsterdam albatross Diomedea...

Global change is contributing to unprecedented expansions of infectious diseases in wildlife. Recurrent avian cholera outbreaks are causing dramatic chick mortality and population decline in endangered albatross colonies on Amsterdam Island, a critical seabird breeding ground in the Southern Indian Ocean. We manufactured a killed vaccine using a Pa...

Marine research conducted in the Bay of Bengal Large Marine Ecosystem (BOBLME) so far largely focused on physical oceanography. • Seabirds are the most under-studied taxon. • At-sea seabird data provide important insights into the individual biology of the species, species-area relationships (the relationship between physical and biological ocean c...

Strong pair bonds generally increase fitness in monogamous organisms, but may also underlie the risk of hampering it when re-pairing fails after the winter season. We investigated whether partners would either maintain contact or offset this risk by exploiting sex-specific favourable niches during winter in a migratory monogamous seabird, the south...

Commercial fisheries currently pose a serious threat at sea to the conservation of a number of pelagic seabirds. However, these interactions are complex, and reports on population-specific bycatch in the high seas are scarce. Here we report the case of an Indian yellow-nosed albatross Thalassarche carteri re-sighted on Amsterdam Island after an app...

Introduced mammals may have deleterious effects on avifauna. We investigated whether such species may be affecting the breeding success of the critically endangered Amsterdam Albatrosses Diomedea amsterdamensis on its remote breeding island. Twelve camera-traps deployed near albatross nests during the chick brooding period in 2011 captured 25,000 p...

Post-breeding migration in land-based marine animals is thought to offset seasonal deterioration in foraging or other important environmental conditions at the breeding site. However the inter-breeding distribution of such animals may reflect not only their optimal habitat, but more subtle influences on an individual's migration path, including suc...

Summary of the MADIFA model for wintering Eudyptes filholi from Crozet and Kerguelen. Values indicate % of variance explained by the three first principal components of the PCAs and scores of the variables on those components. Abbreviations used for the variables: BATHY: bathymetry, BATHYG: gradient of bathymetry, SST: sea-surface temperature, SSTG...

Summary of the MADIFA model for wintering Eudyptes chrysolophus from Crozet and Kerguelen Islands. Values indicate % of variance explained by the three first principal components of the PCAs and scores of the variables on those components. Abbreviations used for the variables: BATHY: bathymetry, BATHYG: gradient of bathymetry, SST: sea-surface temp...

Illustration of the chronological scenario proposed from the paleoenvironments to explain the Eudyptes penguins’ contrasted inter-breeding migration patterns. Cool period during early Pleistocene (A, from 1.9–1.3 to 0.9–0.42 Ma ago), with penguins at Crozet and Kerguelen Islands and putative migration routes (yellow arrows); then (B) warming during...

Migration schedule (peak departure/return dates from the colony) and tagging period of the three species surveyed (the macaroni Eudyptes chrysolophus, the eastern E. filholi and the northern E. moseleyi rockhopper penguins) on the four localities (Marion, Crozet, Kerguelen and Amsterdam Islands). References: *. this study, 8. Thiebot JB, Cherel Y,...

The juvenile phase is poorly known in Antarctic seabirds, despite being a critical period for individual survival. To better understand the ecology of young Antarctic seabirds, we surveyed for the first time the three-dimensional habitat use of six juvenile emperor penguins during their post-natal dispersal from Terre Adélie, using bio-telemetric t...

Seabirds associations with marine mammals have been shown to be an efficient way by which the seabirds can detect and access prey patches. However, these associations have been documented locally in the literature and their relevance at the ecosystem level is unknown, mostly because they constitute relatively rare events and therefore few appropria...

Ecological niche theory predicts segregation mechanisms that mitigate potential competition between closely related organisms. However, little is known outside the breeding season, when central-place foraging animals may move on larger scales. This study tested for segregation mechanisms within the same 2007 inter-breeding period on three neighbori...

For land-breeding marine organisms such as seabirds, knowledge about their habitat use has mainly been gained through studies of breeding individuals that are constrained to return frequently to their breeding grounds. In this study we set out to measure whether: a) habitat selection in the non-breeding period predicts habitat selection in the bree...

The study of scats of adult male Antarctic fur seals Arctocephalus gazella (AFS) revealed occasional frequent capture of penguins. Although AFS adult males have been occasionally reported to kill king penguins Aptenodytes patagonicus at the shore, here we report the first observations of at-sea predation by AFS on adult king penguins in the Crozet...

The development of biologging techniques has been instrumental in studying the behaviour of wild animals and interpreting it with respect to the bio-physical features of their habitat. Light-based geolocation currently appears to be the only technique suitable for the study of farranging small species, particularly marine species, over long periods...

The primary and accepted method used to estimate seabird densities at sea from ships is the strip transect method, designed to correct for the effect of random directional bird movement relative to that of the ship. However, this method relies on the critical assumption that all of the birds within the survey strip are detected. We used the distanc...

Although penguins are key marine predators from the Southern Ocean, their migratory behaviour during the inter-nesting period remains widely unknown. Here, we report for the first time, to our knowledge, the winter foraging movements and feeding habits of a penguin species by using geolocation sensors fitted on penguins with a new attachment method...