Albatrosses have different personalities, and these “characters” influence their fishing strategies, which are intimately linked to wind strength.
Is it better to be content with what you’ve found, or to keep searching? When it comes to food, wandering albatrosses don’t have a clear-cut position; there’s a difference between the “shy” and the “bold”. On June 26, researchers published a study showing a link between the personality of wandering albatrosses and the way they adapt to different wind forces when searching for food. Specialists have shown that birds with a ” shy ” character stop exploiting wind strength earlier than those with a ” bold ” character, when wind strength tends to diminish.
Wandering albatrosses owe their flight and foraging ability to the power of the wind. “We already knew that their flight and foraging behavior aligned with atmospheric conditions, and wind in particular,” says Natasha Gillies, lead editor of the study published in Journal of Animal Ecology.
Albatrosses travel longer distances when winds are strong. When it dies down, the animals rest and wait for air movement to return, while floating on the surface of the water. In such moments, it’s more profitable for them to be on stand-by in a corner of the ocean where food is abundant.
As they travel, they scour the ocean for food, sometimes leaving promising areas behind. They take the risk of missing out in search of even denser plankton and prey aggregations. Conversely, when they linger on in a fishing area, they take fewer risks, adopting an exploitative behavior and performing lots of small flights in a tight space to harvest as much prey as possible. “We call this exploitative versus exploratory behavior”, explains the researcher. Albatrosses switch from one mode to the other during their time at sea. The study shows that personality influences the benefit-risk analysis of each individual.
How can you tell an albatross’s personality?
On the island of Crozet in the French Southern and Antarctic Lands, the Alfred-Fore base albatross colony is an experimental area for the Centre d’Études Biologiques de Chizé, which sends ornithologists from the French Polar Institute to the site every year. Since 2010, ornithologists have been testing the boldness of certain breeding pairs.
They use a scale of 0 to 5 to rate the individual’s personality, with 5 being the highest. At this stage, the bird stands up and leaves the nest in response to the approach of a human being (at more than 5 meters), at 3 it vocalizes and at 0 it doesn’t move. Birds are also fitted with transponders to record their flight at sea.
When winds are strong, “shy” and “reckless” travel longer between patches of plankton. Their chances of finding plenty of food increase. But when the wind drops, the “timid” prefer to exploit a productive area of the ocean, while the “bold” continue to travel and explore.
Between males and females
The distinction between “shy” and “bold” exists in males, but they can’t tell the difference between strong and light winds. “They are so constrained by their size that they can only develop one type of behavior per character,” explains the researcher. The “shy” ones stop more often to exploit a fishing area, and the “bold” ones take more risks and travel longer. In general, males move to areas with stronger winds which usually is further south.
Females are lighter and have smaller wings. They are found in parts of the Southern Ocean where winds are less strong and less regular. Within the female group, the “shy” are able to switch from one fishing strategy to another depending on wind strength and the “bold” ones continue to explore in light winds. This diversity of behavior enables them to adapt to changes in their environment.
Scientists believe that climate change may favor the “bold”. However, if this were to be the case, the diversity of personalities could fade and these bird populations would be less flexible in the face of other changes, with a real risk of ending up with their beaks in the water.
Camille Lin, PolarJournal
Link to the study : Gillies, N., Weimerskirch, H., Thorley, J., Clay, T.A., Martín López, L.M., Joo, R., Basille, M., Patrick, S.C., n.d. Boldness predicts plasticity in flight responses to winds. Journal of Animal Ecology n/a. https://doi.org/10.1111/1365-2656.13968.
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