King penguin population threatened by Southern Ocean warming.

Seabirds are sensitive indicators of changes in marine ecosystems and might integrate and/or amplify the effects of climate forcing on lower levels in food chains. Current knowledge on the impact of climate changes on penguins is primarily based on Antarctic birds identified by using flipper bands. Although flipper bands have helped to answer many questions about penguin biology, they were shown in some penguin species to have a detrimental effect.

Population dynamics in a long-lived seabird: I. Impact of breeding activity on survival and breeding probability in unbanded king penguins.

Understanding the trade-off between current reproductive effort, future survival and future breeding attempts is crucial for demographic analyses and life history studies. We investigated this trade-off in a population of king penguins (Aptenodytes patagonicus) marked individually with transponders using multistate capture-recapture models. This colonial seabird species has a low annual proportion of non-breeders (13%), despite a breeding cycle which lasts over 1 year.

Long-term effects of flipper bands on penguins.

Changes in seabird populations, and particularly of penguins, offer a unique opportunity for investigating the impact of fisheries and climatic variations on marine resources. Such investigations often require large-scale banding to identify individual birds, but the significance of the data relies on the assumption that no bias is introduced in this type of long-term monitoring. After 5 years of using an automated system of identification of king penguins implanted with electronic tags (100 adult king penguins were implanted with a transponder tag, 50 of which were also flipper banded), we can report that banding results in later arrival at the colony for courtship in some years, lower breeding probability and lower chick production.

Performance of differential GPS collars in temperate mountain forest.

To determine the performance of Global Positioning System (GPS) for habitat studies in free-ranging animals, we tested differential 6- and 8-channel GPS collars under six representative canopies and one open-field reference site in the 'Parc national des Cévennes', southern France. The proportion of successful locations decreased under taller trees and worsened with snow accumulation in mixed coniferous habitats. The mean location success of seven free-ranging red deer fitted with 6-channel GPS collars in the same study area increased with a shorter interval between location attempts and during the leaf-off period.

Global Positioning System (GPS) location accuracy improvement due to selective availability removal.

Global Positioning System (GPS) is an important new technology for spatio-temporal behaviour studies of animals. Differential correction improves location accuracy. Previously, it mostly removed partially the influence of Selective Availability (SA).