Aggregation of Larval Lepidoptera: Advantageous or Fatal

The objective of the study was to test the effect of larval gregariousness on avian predator activity in secondary forest in Costa Rica. Clay models resembling larval species of the Geometridae family were placed on plant leaves as solitary and aggregated individuals in an experimental plot, and orange and blue ribbon was used to mark each solitary and aggregated group, respectively. Model attack data was collected every twelve hours, and models that fell off due to rain or other factors were replaced once all groups were checked for evidence of attack. Also, additional models were placed under leaves and on tree branches to investigate if models of different color and size would better attract avian predators and if placing models in different locations would increase the rate of predator attack. Observations made about the foraging behaviors of the rufous-naped wren and the great-tailed grackle, two birds common to the experimental area, were used to determine the locations where avian attack would be the most probable. Results from the experiment were inconclusive due to a lack of data and a lack of validity in the evidence of avian attack. Further research on the perception of birds will need to be conducted to provide insight that could improve the methods of this experiment and possibly produce more conclusive results if the experiment were repeated. Moreover, if the experiment were repeated, choosing an experiment plot away from human habitation may decrease the chances of people interfering with the experiment and increase validity of the data collected