Patterns of feeding in the polyphagous grasshopper Taeniopoda eques: a field study

Abstract Abstract. Detailed field observations were made of the feeding behaviour of the polyphagous grasshopper Taeniopoda eques (Burmeister), in its desert habitat in the southwestern United States. Twelve adult females were observed continuously throughout the day, including three on overcast days and nine on sunny days. Insects observed on sunny days had two foraging periods, one in the morning and one in the afternoon, separated by an extended period of roosting. By contrast, those observed on overcast days had no extended midday roost and tended to feed intermittently throughout the day. Analysis of the patterns of feeding showed that feeding events were clustered into meals separated by inter-meal intervals of 8 min or longer. The insects almost always ascended a perch and took postprandial rests between meals. Those observed on sunny days locomoted less and spent a greater proportion of the inter-meal intervals quiescent, partly as a result of taking longer postprandial rests. The time spent feeding within meals was positively related to the amount of time spent locomoting in the preceding inter-meal interval (preprandial correlation), and negatively related to the time spent locomoting in the following inter-meal interval (postprandial correlation). A high degree of individual polyphagy was observed, with individual insects feeding on up to 30 food items per day and single meals consisting of feeds on up to 11 different food items. Increased food mixing was associated with increased locomotion. These patterns of feeding are compared with those previously observed in laboratory studies of insects.