Seabirds of habit

As featured on the journal Oikos’ website, here’s a post about my latest research on how kittiwakes adapt their behaviour to the environment…

Black-legged kittiwakes choose their foraging habitat in response to changes in the tidal cycle, and environmental heterogeneity. The study tracked birds from three sites around the Irish Sea using GPS loggers, including from Puffin Island, pictured.

Breakfast at the nearest coffee shop in the morning, lunch from the local convenience store, quick drink in your regular on the way home. Sound familiar? Just like we can be creatures of habit, new research has revealed that seabirds, too, adapt to hourly cycles to choose where to eat.

What’s more, our study revealed that the more varied the environment was, the more seabirds changed where they go over the predictable cycle. So if we only had supermarkets, we’d have to go there for all of our food. But faced with cafes and bakeries, pubs and restaurants, we can choose where to go depending on whether it’s time for breakfast, lunch, or a G&T.

We used miniature GPS trackers to record how seabirds use the marine environment according to the state of the tide – the regular change in sea level caused by the rotation of earth and the moon’s gravity. As the tide rises and falls, water currents flow around the coast and change where fish are, and how easily seabirds can catch them. Because the tide is predictable, seabirds can learn where makes for good fishing, and when.

This study is the first to document changes in feeding habitat choice over such fine scales, and how important it is to consider variability in the environment at the same time. For all animals, adapting to predictable cycles and environmental variability could be a vital chance to find food efficiently, and conserve energy for survival and reproduction. As environments are changing, even fine scale changes in behaviour, like the ones we show in this study, are important for our seabirds, many of which are declining. They are important for us too, as by uncovering the finer details of how animals find food, we can learn more from animals about the health of our ecosystems, and do more to protect them.

The paper ‘Environmental heterogeneity amplifies behavioural response to a temporal cycle’ involved researchers from the National Oceanography Centre, Liverpool, and Deakin University, Australia.

Interactions between tidal currents and the sea floor can create predictable changes in resources, which influence seabird behaviour. This picture off the north coast of Northern Ireland shows tidal currents at the surface caused by the headland in the foreground, and Rathlin Island – one of the study sites – in the background. (Picture: Alice Trevail)

Graphical abstract for the paper, showing our main findings