How do mantis shrimp fight in a community of competitors?

About the Project

What are the strategies that animals use when competing over essential resources like mates, food, or shelter? Decades of animal behavior research into this question has identified several tactics animals may use. However, most studies do not realistically replicate the problem competing animals face in nature. For example, most experimental studies stage contests between two individuals over one resource; in reality, animals likely interact with a population of multiple competitors, all fighting over multiple resources. Understanding how animals fight in these more naturalistic scenarios will help us discover the strategies animals use in natural systems, while reaffirming or contesting the conclusions of previous work.

This study intends to track how a population of individuals compete over multiple resources by studying contests in mantis shrimp, crustaceans that use spring-powered strikes during fights over access to protective burrows. Specifically, we will set up “mesocosms”, large areas holding multiple, individually-marked mantis shrimp and multiple burrows. By tracking each individual over weeks to months, we can see who fights with whom, what their contests are like (e.g., how aggressive), and who ends up holding which resource(s).

The primary objectives of this project will be to build methods to track uniquely-marked individuals from video recordings, and to identify timestamps in videos when two individuals come into contact (perhaps leading to a fight). Finally, an additional goal of this project will be to gather movement and residence data from each individual—identifying how much individuals move through their environment and which resource(s) they ultimately hold. The methods from this project will form the basis for a long-term project that modifies this approach for multiple experiments in the future.