EFFECTS OF FOOD-DEPRIVATION AND OLFACTORY AND VISUAL CUES ON MOVEMENTPATTERNS OF 2 ELEODES SPECIES (COLEOPTERA, TENEBRIONIDAE) IN A WIND-TUNNEL

Terrestrial arthropods are challenged with locating food in a heteroge neous environment, and this activity may be mediated by the hunger lev el the animal is experiencing. We performed wind tunnel experiments to determine whether food deprivation in the terrestrial darkling beetle s Eleodes extricata Say and Eleodes hispilabris Say affects their move ment patterns and whether they orient to food by means of vision, olfa ction, or both. Hunger affected foraging behavior with respect to whet her beetles actually contacted food. However, the velocity and number of turns of both food-deprived and fed individuals did not significant ly differ, indicating that food deprivation affects the ethological co nsequences but not the velocity and turning mechanics of foraging in t hese species. Both olfaction and vision were used to find food over sh ort distances (<80 cm). Olfaction elicited a stronger navigational res ponse than did vision, particularly within 25 cm of food.