Research shows female fish judge males on DIY skills

Female fish judge males based on their ability to design nests best suited for the conditions of their environment, according to a new study by researchers from the Department of Neuroscience, Psychology and Behaviour.

In the study, which is published today, biologists at our University, the Australian National University (ANU) and the University of Technology Sydney (UTS) have shown that low oxygen can change the way in which fish build nests, and also change the nesting preferences of female fish.

Male three-spined stickleback fish are unusual in that they build nests and provide all the parental care for the eggs, which are spawned by females, and for the developing baby fish. The research team found that males change the design of their nests depending on the oxygen content of the water – making looser nests under low-oxygen conditions and more compact nests when oxygen increases.

“This makes sense, because male sticklebacks have to work really hard as dads, using their fins to fan water through the nest to supply the eggs with the oxygen they need to develop,” said lead researcher, Leicester biologist Dr Iain Barber. “If the water is low in oxygen, then having a looser, more open nest allows more oxygen to reach the eggs, but it probably comes at the expense of increasing the risk of them being discovered by predators.”

Flexible nest preferences might give sticklebacks a real advantage in rapidly changing environments. One problem animals in degraded habitats often face is that the decisions they make are shaped by their evolutionary history, with the result that they end up making choices that are no longer beneficial under changed conditions. The fact that sticklebacks appear to be able to moderate their behaviour and their decision-making dependent on local conditions might mean they might be able to cope better in degraded environments.

Dr Barber has previously advised the BBC Springwatch team on the behaviour of sticklebacks and his research into stickleback nest building and parental care has featured on BBC’s ONE Show.

• The University of Leicester conducts fundamental and applied research across all disciplines creating a strong culture of interaction, sharing and learning, helping to deliver an outstanding education for its students.

A video of stickleback nest building behaviour is available below: