|Penguins foraging as a group.|
Photo credit: John Arnould, Deakin University
Group foraging has advantages for cooperative predators. But the benefits of group foraging are not as clear for less cooperative predators like little penguins, because of the potential for competition. The authors of this study attached cameras to 21 little penguins from two breeding colonies in south-eastern Australia to determine their prey types, hunting strategies and success.
The researchers found that little penguins were more likely to associate with each other when hunting schooling prey than when hunting solitary prey. Surprisingly, individuals were no more successful at capturing schooling prey than solitary prey. However, when penguins hunted schooling fish they had more or similar success when they hunted on their own rather than together. The authors suggest that individual penguins may trade-off the potential benefits of solitary hunting to increase their chances of spotting prey by working with other little penguins.
Grace Sutton said, "This study showed little penguins gained no benefit in capturing prey when hunting in groups, suggesting individuals may forage in groups to improve detection of prey or avoid predation but, once they find prey, it is every penguin for themselves."
Penguin cam captures hunt for prey, PLOS, 16 December 2015, EurekaAlert!
Sutton GJ, Hoskins AJ, Arnould JPY (2015) Benefits of Group Foraging Depend on Prey Type in a Small Marine Predator, the Little Penguin. PLoS ONE 10(12): e0144297. doi:10.1371/journal. pone.0144297