FIGHTING AND ASSESSMENT IN THE NET-SPINNING CADDIS LARVA ARCTOPSYCHE-LADOGENSIS - A TEST OF THE SEQUENTIAL ASSESSMENT GAME

Eight qualitative predictions from the sequential assessment game were tested using net-spinning caddisfly larvae Arctopsyche ladogensis which fight over silk retreats and catchnets. The results agree with predictions regarding effects of relative size and ownership. Size was crucial for the outcome of contests, large specimens usually winning. Both contest duration and the standard deviation of contest durations were negatively correlated with the relative size of the opponents. Owners were more persistent than intruders, and they won most of the contests. In contests where both opponents regarded themselves as owners, contests lasted longer than owner-intruder ones. Contrary to predictions from the sequential assessment game, resource value in terms of amount of silk invested or amount of food obtained in the net did not influence contest outcome or duration. It is concluded that the sequential assessment game predicted the effects of relative size and ownership but not the effects of resource value. © 1990 The Association for the Study of Animal Behaviour.