Researchers discover behavioral phenomenon in swans - study

By observing agression, rest and maintenance such as preening and cleaning feathers, the researchers found that the energy expended by aggressive behavior reduced the swans' resting time.

An adult mute swan (Cygnus olor) in a pond near Vrhnika, Slovenia (photo credit: Yerpo/CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)/VIA WIKIMEDIA COMMONS)
An adult mute swan (Cygnus olor) in a pond near Vrhnika, Slovenia
(photo credit: Yerpo/CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)/VIA WIKIMEDIA COMMONS)

Researchers at the University of Exeter and the Wildfowl & Wetlands Trust (WWT) studied the behavior of mute and whooper swans in order to find out how they spent their time and energy in a study that could allow the construction of habitats designed to reduce agression.

In a peer-reviewed study published in PLOS One on Friday, the researchers observed the swans over a livestream from a camera at WWT Caerlaverock nature reserve in Scotland.

Whooper swans, which are migratory birds, often go to the reserve during the winter, while mute swans are there all year and are therefore more "flexible" behavior as they don't have as dire a need to store fat as whooper swans, according to Dr. Paul Rose of the University of Exeter and WWT.

"By providing enough foraging spots for the birds, we can reduce the need for aggression around desirable feeding spots, giving them more time to rest," he said. "This can help to ensure that migratory species don’t 'push out' non-migratory species when they mix in the same wintering locations.

By observing agression, rest and maintenance such as preening and cleaning feathers, the researchers found that the energy expended by aggressive behavior reduced the swans' resting time.

A scientist looks through a microscope (credit: INGIMAGE)A scientist looks through a microscope (credit: INGIMAGE)

Trade-off

"Our observations of two overwintering swan species are consistent with the idea that birds can trade-off their time investments in mutually exclusive behaviours within their time-activity budgets, at least over short time periods."

Study

The researchers found that swans "trade-off" their time investments in certain behaviors.

"Our observations of two overwintering swan species are consistent with the idea that birds can trade-off their time investments in mutually exclusive behaviours within their time-activity budgets, at least over short time periods," the study read. "For both of our study species, negative associations between foraging and resting, and between resting and aggression, suggest that swans can trade-off time investment in these behaviours. However, we also recognise that it is difficult to draw broader conclusions about the implications of such patterns of behaviour, including fitness impacts, from short-term observations conducted over periods of 15 minutes."

Implications of the study

The study helps scientists understand how the behavior of these birds changes when they get into fights.

"Our study also demonstrates how remotely collected data can be used to investigate fundamental questions in behavioural research," Rose added.