Akiko Kato

Akiko Kato
French National Centre for Scientific Research | CNRS · Centre d'Etudes Biologiques de Chizé (CNRS & La Rochelle Université)

PhD

About

241
Publications
53,077
Reads
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7,353
Citations
Additional affiliations
June 2016 - present
Centre d'Etudes Biologique de Chizé
Position
  • Ingénieurs de recherche
December 2009 - May 2016
Institut Pluridisciplinaire Hubert Curien
Position
  • Ingénieurs de recherche
April 1999 - December 2007
The Graduate University for Advanced Studies
Position
  • Research Associate
Education
March 1998 - March 1998
Hokkaido University
Field of study
April 1992 - September 1993
Tokyo University of Fisheries
Tokyo University of Fisheries
Field of study
April 1990 - March 1992
Waseda University
Field of study
  • Ecology

Publications

Publications (241)
Article
Full-text available
Niche theory predicts that to reduce competition for the same resource, sympatric ecologically similar species should exploit divergent niches and segregate in one or more dimensions. Seasonal variations in environmental conditions and energy requirements can influence the mechanisms and the degree of niche segregation. However, studies have overlo...
Article
Full-text available
Sexual segregation is common in many species and has been attributed to intra-specific competition, sex-specific differences in foraging efficiency or in activity budgets and habitat choice. However, very few studies have simultaneously quantified sex-specific foraging strategies, at sea distribution, habitat use, and trophic ecology. Moreover, the...
Article
Full-text available
King penguins ( Aptenodytes patagonicus ) are an iconic Southern Ocean species, but the prey distributions that underpin their at-sea foraging tracks and diving behaviour remain unclear. We conducted simultaneous acoustic surveys off South Georgia and tracking of king penguins breeding ashore there in Austral summer 2017 to gain insight into habita...
Article
Foraging behaviour is crucial to breeding success for marine predators, including seabirds. Yellow-eyed penguins Megadyptes antipodes are central-place, predominantly benthic foragers around mainland New Zealand. The northern (mainland) population of this Endangered species is declining, with changes in the marine environment a suspected cause, par...
Preprint
Full-text available
Niche theory predicts that to reduce competition for the same resource, sympatric ecologically similar species should exploit divergent niches and segregate in one or more dimensions. Seasonal variations in environmental conditions and energy requirements can influence the mechanisms and the degree of niche segregation. However, studies have overlo...
Article
In many bird species, reproductive partners sing together each time they meet on the nest. Because these nest ceremonies typically correspond to the return of one partner from foraging and to the subsequent departure of the other partner, we hypothesized that the foraging decisions of departing birds may be facilitated by the vocalizations accompan...
Article
Full-text available
As extreme weather is expected to become more frequent with global climate change, it is crucial to evaluate the capacity of species to respond to short-term and unpredictable events. Here, we examined the effect of a strong storm event during the chick-rearing stage of little penguins (Eudyptula minor) from a mega colony in southern Australia. We...
Article
Metamorphosis is a widespread developmental process that involves considerable changes in morphology, habitat use, ecology and behaviour between early developmental (larval) stages and adult forms. Among amphibians, anuran larvae (tadpoles) undergo massive morphological and ecological changes during their development, with early stages characterize...
Article
Full-text available
Background Energy landscapes provide an approach to the mechanistic basis of spatial ecology and decision-making in animals. This is based on the quantification of the variation in the energy costs of movements through a given environment, as well as how these costs vary in time and for different animal populations. Organisms as diverse as fish, ma...
Article
Full-text available
Seabirds allocate different amounts of energy to reproduction throughout the breeding season, depending on the trade-off between their own needs and those of their chicks and/or changes in environmental conditions. Provisioning parents therefore modulate their foraging behaviour and diet accordingly. However, for diving seabirds, many studies have...
Article
Full-text available
Diving is an ecologically important behaviour that provides air-breathing predators with opportunities to capture prey, but that also increases their exposure to incidental mortality (bycatch) in commercial fisheries. In this study, we characterised the diving behaviour of 26 individuals of three species, the black-browed albatross Thalassarche mel...
Article
Full-text available
There is a growing interest in studying consistency and site fidelity of individuals to assess, respectively, how individual behaviour shapes the population response to environmental changes, and to highlight the critical habitats needed by species. In Antarctica, the foraging activity of central place foragers like Adélie penguins ( Pygoscelis ade...
Article
Overabundant species can have major impacts on their habitat and induce trophic cascades within ecosystems. In North America, the overabundant greater snow goose (Anser caerulescens atlanticus) has been successfully controlled through special spring hunting regulations since 1999. Hunting is a source of mortality but also of disturbance, which affe...
Article
Full-text available
Energy drives behaviour and life history decisions, yet it can be hard to measure at fine scales in free-moving animals. Accelerometry has proven a powerful tool to estimate energy expenditure, but requires calibration in the wild. This can be difficult in some environments, or for particular behaviours, and validations have produced equivocal resu...
Article
Full-text available
Most Procellariform seabirds are pelagic, breed in summer when prey availability peaks, and migrate for winter. They also display a dual foraging strategy (short and long trips) and sex-specific foraging. The Westland petrel Procellaria westlandica, a New Zealand endemic, is one of the rare seabirds breeding in winter. Preliminary findings on this...
Article
Full-text available
Individual heterogeneity in diet and foraging behaviour is common in wild animal populations, and can be a strong determinant of how populations respond to environmental changes. Within populations, variation in foraging behaviour and the occurrence of individual tactics in relation to resources distribution can help explain differences in individu...
Article
Full-text available
Reduced human mobility during the pandemic will reveal critical aspects of our impact on animals, providing important guidance on how best to share space on this crowded planet.
Article
Sentinel species, like Adélie penguins, have been used to assess the impact of environmental changes, and their link with sea ice has eceived considerable attention. Here, we tested if foraging Adélie penguins from 2 colonies in East Antarctica target the distant sea-ice edge or take advantage of closer open waters that are readily available near t...
Article
Full-text available
1. Changes in marine ecosystems are easier to detect in upper-level predators, like seabirds, which integrate trophic interactions throughout the food web. 2. Here, we examined whether diving parameters and complexity in the temporal organisation of diving behaviour of little penguins (Eudyptula minor) are influenced by sea surface temperature (SS...
Article
Full-text available
Southern Ocean ecosystems are under pressure from resource exploitation and climate change1,2. Mitigation requires the identification and protection of Areas of Ecological Significance (AESs), which have so far not been determined at the ocean-basin scale. Here, using assemblage-level tracking of marine predators, we identify AESs for this globally...
Article
Full-text available
There is a paucity of information on the foraging ecology, especially individual use of sea-ice features and icebergs, over the non-breeding season in many seabird species. Using geolocators and stable isotopes, we defined the movements, distribution and diet of adult Antarctic petrels Thalassoica antarctica from the largest known breeding colony,...
Article
Full-text available
The Retrospective Analysis of Antarctic Tracking Data (RAATD) is a Scientific Committee for Antarctic Research project led jointly by the Expert Groups on Birds and Marine Mammals and Antarctic Biodiversity Informatics, and endorsed by the Commission for the Conservation of Antarctic Marine Living Resources. RAATD consolidated tracking data for mul...
Article
The Retrospective Analysis of Antarctic Tracking Data (RAATD) is a Scientific Committee for Antarctic Research project led jointly by the Expert Groups on Birds and Marine Mammals and Antarctic Biodiversity Informatics, and endorsed by the Commission for the Conservation of Antarctic Marine Living Resources. RAATD consolidated tracking data for mul...
Article
Full-text available
• The most western little penguin colony globally, and the most northern in Western Australia (WA) is found on Penguin Island, WA. The penguins use coastal bays that are also used extensively by recreational watercraft. These penguins have been found to either dive predominantly to shallow depths of 1–5 m or to depths >8 m. It is thus hypothesized...
Article
Full-text available
1) The early‐life of animals is a period of high mortality, when foraging capacities are assumed to be improved progressively. In birds, this critical period involves the improvement of the flight. How do young birds gain these capacities has rarely been studied in natural conditions especially in seabirds that spend most of their life at sea. 2) W...
Data
1) The early-life of animals is a period of high mortality, when foraging capacities are assumed to be improved progressively. In birds, this critical period involves the improvement of the flight. How do young birds gain these capacities has rarely been studied in natural conditions especially in seabirds that spend most of their life at sea. 2)...
Article
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...
Article
Central place foragers rely on areas within a small range of their breeding grounds for chick provisioning. Therefore there exists a tight coupling between their breeding success and local bio-physical conditions. The effects of fine-scale variability in environmental parameters and resource distribution on the foraging behaviour of marine predator...
Article
Southern Ocean ecosystems are extremely vulnerable to sea-ice changes occurring at different spatial and temporal scales. Variability in the sea-ice conditions strongly influence the survival and reproduction of animals that are synchronized with the seasonality of sea ice. Although the linkages between Adélie penguins (Pygoscelis adeliae) and sea-...
Article
Full-text available
Penguins face a wide range of threats. Most observed population changes have been negative and have happened over the last 60 years. Today, populations of 11 of the 18 penguin species are decreasing. Here we present a review that synthesizes details of threats faced by the world’s 18 species of penguins. We discuss alterations to their environment...
Article
Breeding in most species is timed to coincide with the greatest availability of food resources to support the increased energetic needs of reproduction. Correspondingly, the majority (76%) of seabird species in temperate and polar regions breed in spring/summer, matching the peak in ocean productivity. The Fiordland penguin Eudyptes pachyrhynchus i...
Preprint
Full-text available
Sexual segregation is common in many species and has been attributed to intra-specific competition, sex-specific differences in foraging efficiency or in activity budgets and habitat choice. However, very few studies have simultaneously quantified sex-specific foraging strategies, at sea distribution, habitat use, and trophic ecology. Moreover, the...
Article
Full-text available
Central-place foraging in large seabird colonies leads to high levels of intra-specific competition for food resources, often resulting in between-colony spatial segregation. However, little is known about within-colony variation in foraging behaviour that may arise from breeding locations. Using little penguins Eudyptula minor from a large colony...
Data
This webpage is a scientific database where you will find official records of dive depth and duration for most diving species of vertebrates. This project was initiated to answer the questions regularly asked by school teachers, educators, journalists, scientists: "How deep can animals dive?". Such information is compiled here, using references fro...
Presentation
Under climate change, seabirds can provide a means to monitor rapid changes in the marine environment. An emerging approach uses fractal analysis to assess structural complexity in behavioural sequences, yet identifying how such complexity is affected by intrinsic and extrinsic parameters remains underexplored. Here, we examined how diving paramete...
Article
In the d'Urville Sea in East Antarctica, a population of roughly 20,000 pairs of Adélie penguins of Iles des Pétrels (Terre Adélie) has experienced two massive breeding failures, with no chick surviving the 2013–14 and 2016–17 breeding seasons. In both seasons the extent of sea ice in front of the colony persisted throughout the breeding cycle of t...
Article
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...
Article
Gastrointestinal nematodes are known to be one of the most economically important parasites in livestock production. In order to test whether fractal analysis of behaviour can be used as a diagnostic tool for detection of infected animals, we investigated fractal patterns in the behavioural activity of domestic sheep (Ovis aries) in relation to str...
Presentation
Due to ongoing climate change, it is necessary to understand how ecosystems and food webs are affected by these environmental changes. As upper-level predators, seabirds’ behaviour provides a way to monitor changes occurring in the marine environment, but identifying how the complexity in the temporal structure of behaviour depend on intrinsic and...
Article
Full-text available
Jellyfish and other pelagic gelatinous organisms (“gelata”) are increasingly perceived as an important component of marine food webs but remain poorly understood. Their importance as prey in the oceans is extremely difficult to quantify due in part to methodological challenges in verifying predation on gelatinous structures. Miniaturized animal-bor...
Article
Full-text available
Background: Foraging efficiency determines whether animals will be able to raise healthy broods, maintain their own condition, avoid predators and ultimately increase their fitness. Using accelerometers and GPS loggers, features of the habitat and the way animals deal with variable conditions can be translated into energetic costs of movement, whic...
Article
Full-text available
Little penguins (Eudyptula minor) have one of the widest geographic distributions among penguins, exposing them to variable ecological constraints across their range, which in turn can affect their foraging behaviour. Presumably, behavioural flexibility exists to allow animals to adapt to prevailing environmental conditions throughout their foragin...
Article
Several biological functions, such as reproductive success, peak during middle age in long-lived vertebrates. One possible mechanism for that peak is improved foraging performance during middle age, after a period of youthful inexperience and before senescence. Age may be particularly important in relating foraging behaviour to fitness for diving a...
Article
Full-text available
In polar seas, the seasonal melting of ice triggers the development of an open-water ecosystem characterized by short-lived algal blooms, the grazing and development of zooplankton, and the influx of avian and mammalian predators. Spatial heterogeneity in the timing of ice melt generates temporal variability in the development of these events acros...
Article
Full-text available
The identification of feeding events is crucial to our understanding of the foraging ecology of seabirds. Technology has made small devices, such as time-depth recorders (TDRs) and accelerometers available. However, TDRs might not be sensitive enough to identify shallow dives, whereas accelerometers might reveal more subtle behaviours at a smaller...
Article
Full-text available
In polar seas, the seasonal melting of ice triggers the development of an open-water ecosystem characterized by short-lived algal blooms, the grazing and development of zooplankton and the influx of avian and mammalian predators. Spatial heterogeneity in the timing of ice melt generates temporal variability in the development of these events across...
Article
Modeling metapopulation dynamics is potentially a useful and powerful tool for ecologists and conservation biologists. However, the key processes driving metapopulation dynamics are colonization and extinction events, which are notoriously difficult to study. A recent global assessment of Adelie Penguin (Pygoscelis adeliae) breeding populations rep...
Data
Commercial fisheries may impact marine ecosystems and affect populations of predators like seabirds. In the Southern Ocean, there is an extensive fishery for Antarctic krill Euphausia superba that is projected to increase further. Comparing distribution and prey selection of fishing operations versus predators is needed to predict fishery-related i...
Poster
Full-text available
In recent years, the possibility to track large numbers of seabirds has driven the development of several methods to determine foraging areas from GPS only data. These models analyse gps locations and use data such as speed, trajectory and turning angle to locate in time and space some basic behaviour of seabirds, such as foraging, flight and resti...
Poster
Full-text available
Recent technology has made available small and accurate devices such as accelerometers and Time Depth Recorders (TDRs) which can be deployed on marine birds for several days. While TDRs have been specifically designed for measuring depth, accelerometers are increasingly used to identify body movements and behaviour. Sometimes a TDR might not be sen...