Congratulations to Will Sowersby and Nicholas Deal for each being awarded grants from the Holdsworth Wildlife Research Endowment for their PhD projects.
Small male fish use high aggression strategy
A new study is shedding light on the aggressive mating behaviour of smaller nest-holding males. We quantified initiation of aggression in a fish, the desert goby by exposing nest-holding males to a male intruder. The perceived value of the resource was manipulated by exposing half of the residents to sexually receptive females for two days before the trial. Resident male aggression, however, was unaffected by perceived mating opportunities. It was also unaffected by the absolute and relative size of the intruder. Instead resident aggression was negatively related to resident male size. In particular, smaller residents attacked sooner and with greater intensity compared to larger residents. These results suggest that resident desert goby males used set, rather than conditional, strategies for initiating aggression. If intruders are more likely to flee than retaliate, small males may benefit from attacking intruders before these have had an opportunity to assess the resident and/or the resource.
(Photo: Andreas Svensson)
Read a popular article and accompanying video about the research here
