Data for: Geolocation and immersion loggers reveal year-round residency and consequent nutrient deposition rates of adult red-footed boobies in the Chagos Archipelago, tropical Indian Ocean

Bio-logging has revealed much about high-latitude seabird migratory
strategies, but migratory behaviour in tropical species may differ, with
implications for understanding nutrient deposition. Here we use combined
light-level and saltwater immersion loggers to study the year-round
movement behaviour of adult red-footed boobies (Sula sula rubripes) from
the Chagos Archipelago, tropical Indian Ocean to assess migratory
movements and estimate nutrient deposition rates based on the number of
days they spent ashore. Light levels suggest that red-footed boobies are
resident in the Chagos Archipelago year-round, although there are large
latitudinal errors this close to the equator. Immersion data also indicate
residency with tracked birds returning to land every one or two days.
Spending an average of 79.86 ± 2.80 days and 280.84 ± 2.64 nights per year
on land allows us to estimate that the 21,670 pairs of red-footed boobies
deposit 37.34 ± 0.56 tonnes year-1 of guano-derived nitrogen throughout
the archipelago. Our findings have implications for tropical seabird
conservation and phylogenetics, as well as for assessing the impact of
seabird nutrients on coral reef ecosystems.