Yvon Le Maho - Academia.edu (original) (raw)
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Papers by Yvon Le Maho
Proceedings. Biological sciences / The Royal Society, Jan 22, 2014
How natural climate cycles, such as past glacial/interglacial patterns, have shaped species distr... more How natural climate cycles, such as past glacial/interglacial patterns, have shaped species distributions at the high-latitude regions of the Southern Hemisphere is still largely unclear. Here, we show how the post-glacial warming following the Last Glacial Maximum (ca 18 000 years ago), allowed the (re)colonization of the fragmented sub-Antarctic habitat by an upper-level marine predator, the king penguin Aptenodytes patagonicus. Using restriction site-associated DNA sequencing and standard mitochondrial data, we tested the behaviour of subsets of anonymous nuclear loci in inferring past demography through coalescent-based and allele frequency spectrum analyses. Our results show that the king penguin population breeding on Crozet archipelago steeply increased in size, closely following the Holocene warming recorded in the Epica Dome C ice core. The following population growth can be explained by a threshold model in which the ecological requirements of this species (year-round ice-...
Marine Ecology Progress Series, 2004
We investigated the use of Antarctic waters by king penguins in a 2 yr study based on the satelli... more We investigated the use of Antarctic waters by king penguins in a 2 yr study based on the satellite tracking of 10 penguins from the Crozet Islands (SW Indian Ocean). All the penguins travelled towards the pack ice, with 3 of them ending their journey at the edge between the marginal ice and the dense pack ice. The mean maximum foraging range and minimal distance travelled were 1620 and 4095 km, respectively. The effect of the satellite transmitter (PTT) attachment on foraging trip duration and colony attendance was much more important in winter in comparison to the summer. The penguins spent around 24% of their trip at sea in the marginal ice zone. They explored the ice-covered habitat non-randomly as revealed by compositional analysis. The marginal ice was more used than free ice and floes areas. The strategy of travelling towards the marginal ice zone during winter ensures that the penguins have access to predictable feeding areas at a time when food availability is very low in the polar frontal zone. The diet of king penguins when foraging in Antarctic waters is unknown but may be different to their summer food at the Polar Front.
Journal of Zoology, 2008
To determine what kind of factors are implied in the decline of long-distance birds, knowledge on... more To determine what kind of factors are implied in the decline of long-distance birds, knowledge on feeding ecology in breeding and wintering areas is essential. We present the first study recording the quantity and quality of food eaten by a population of black storks Ciconia nigra in the Africa wintering zone, as well as prey abundance in the field by testing an eventual foraging strategy based on the selection of biotic parameters of fish prey (body size, energy gain, swimming speed and fish armaments). Black storks preferentially selected two fish species of Siluriforms that were not the most abundant species in the field. Storks carried out interspecific selection according to the swimming speed of fish species and intraspecific selection depending on prey size, probably to avoid defensive armaments of the preferred fish prey. Small fishes consumed by the birds constituted 91% of the diet and 45% of the total food energy intake. Small fishes were more frequently caught than large ones, even if the storks sometimes took the opportunity to catch large fishes that provided a high energy gain. Energy assimilation of black storks is almost twofold higher than the estimated daily energy expenditure. This study suggests that the quantity of food would satisfy the energy requirements of the species during the winter in Africa, enable them to store reserves and ensure their survival in the African areas.
Proceedings. Biological sciences / The Royal Society, Jan 22, 2014
How natural climate cycles, such as past glacial/interglacial patterns, have shaped species distr... more How natural climate cycles, such as past glacial/interglacial patterns, have shaped species distributions at the high-latitude regions of the Southern Hemisphere is still largely unclear. Here, we show how the post-glacial warming following the Last Glacial Maximum (ca 18 000 years ago), allowed the (re)colonization of the fragmented sub-Antarctic habitat by an upper-level marine predator, the king penguin Aptenodytes patagonicus. Using restriction site-associated DNA sequencing and standard mitochondrial data, we tested the behaviour of subsets of anonymous nuclear loci in inferring past demography through coalescent-based and allele frequency spectrum analyses. Our results show that the king penguin population breeding on Crozet archipelago steeply increased in size, closely following the Holocene warming recorded in the Epica Dome C ice core. The following population growth can be explained by a threshold model in which the ecological requirements of this species (year-round ice-...
Marine Ecology Progress Series, 2004
We investigated the use of Antarctic waters by king penguins in a 2 yr study based on the satelli... more We investigated the use of Antarctic waters by king penguins in a 2 yr study based on the satellite tracking of 10 penguins from the Crozet Islands (SW Indian Ocean). All the penguins travelled towards the pack ice, with 3 of them ending their journey at the edge between the marginal ice and the dense pack ice. The mean maximum foraging range and minimal distance travelled were 1620 and 4095 km, respectively. The effect of the satellite transmitter (PTT) attachment on foraging trip duration and colony attendance was much more important in winter in comparison to the summer. The penguins spent around 24% of their trip at sea in the marginal ice zone. They explored the ice-covered habitat non-randomly as revealed by compositional analysis. The marginal ice was more used than free ice and floes areas. The strategy of travelling towards the marginal ice zone during winter ensures that the penguins have access to predictable feeding areas at a time when food availability is very low in the polar frontal zone. The diet of king penguins when foraging in Antarctic waters is unknown but may be different to their summer food at the Polar Front.
Journal of Zoology, 2008
To determine what kind of factors are implied in the decline of long-distance birds, knowledge on... more To determine what kind of factors are implied in the decline of long-distance birds, knowledge on feeding ecology in breeding and wintering areas is essential. We present the first study recording the quantity and quality of food eaten by a population of black storks Ciconia nigra in the Africa wintering zone, as well as prey abundance in the field by testing an eventual foraging strategy based on the selection of biotic parameters of fish prey (body size, energy gain, swimming speed and fish armaments). Black storks preferentially selected two fish species of Siluriforms that were not the most abundant species in the field. Storks carried out interspecific selection according to the swimming speed of fish species and intraspecific selection depending on prey size, probably to avoid defensive armaments of the preferred fish prey. Small fishes consumed by the birds constituted 91% of the diet and 45% of the total food energy intake. Small fishes were more frequently caught than large ones, even if the storks sometimes took the opportunity to catch large fishes that provided a high energy gain. Energy assimilation of black storks is almost twofold higher than the estimated daily energy expenditure. This study suggests that the quantity of food would satisfy the energy requirements of the species during the winter in Africa, enable them to store reserves and ensure their survival in the African areas.