Antlions are predatory insects known as doodle bugs. They are often found in sandy habitats that have some shielding from rainfall. They have a worldwide distribution and are relatively common in Georgia. Antlion larvae are ambush predators that create pits in the sand to capture their prey. Their main food sources are small insects that fall into their pits. Preliminary data from other experiments indicate that antlions show a strong preference for fine sand habitats. Are antlions able to construct the most successful pits only in these environments? Can anlions successfully survive and hunt in less ideal habitats? In the following study, predation success and pit trap dimensions were measured in the common, pit-making antlion species, Myrmeleon immaculatus, in several types of habitats. Antlion success was compared in the optimal habitat (fine sand) and in four suboptimal habitats (course sand, sand with small pebbles, sand with 25% clay, and sand with 50% clay). Forty antlions were placed into seperate containers with each soil type for 1 week. They were given 2 days to make their pits and then supplied with 2 ants a day to measure both predation success, predation effort (mandible strikes), and time to preay capture. Preliminary results indicate that antlions capture success is greater in dry, fine-sand environments. Prey have the most difficulty escaping pits constructed in the fine sinad since the pit walls often collapse as they attempt to climp out of the pit. The more times the prey falls to the bottom of the pit, the more chances the antlion has to impale it with its mandibles and capture the prey. Antlions are able to capture prey in suboptimal habitats; however, greater soil moisture and larger soil grane size provide escape advantages for the prey.


GGC Dept. of Biology

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