Effects of supplemental food and corticosterone treatment on begging and feeding behavior in Florida Scrub-Jays (Aphelocoma coerulescens)


Meeting Abstract

132.5  Monday, Jan. 7  Effects of supplemental food and corticosterone treatment on begging and feeding behavior in Florida Scrub-Jays (Aphelocoma coerulescens) ELDERBROCK, EK*; SMALL, TW; SCHOECH, SJ; University of Memphis; University of Memphis; University of Memphis kldrbrck@memphis.edu

Begging is believed to communicate an honest signal of a nestling’s nutritional needs. When a nestling requires more food, it will beg to elicit feeding from its parents. The rate and duration of this behavior and the parental response may be influenced by a number of factors. In this study we investigated the roles of two such factors: 1) food availability through supplemental feeding and 2) an individual’s corticosterone (CORT) levels, a hormone known to influence begging and parental behavior. We studied the role of food availability by indirectly supplementing all nestling Florida Scrub-Jays (Aphelocoma coerulescens) within a brood by providing ad libitum supplemental food (meal worms) to their parents during the nesting period. The role of CORT was examined by feeding one nestling per assigned CORT treated nest a CORT-injected wax worm twice-daily for 4 days (Days 8-11 post-hatch) and a second nestling in the same nest a vehicle-injected wax worm. We quantified nestling and adult behaviors using high definition videos recorded with a camera set atop a pole (3-6 meters tall) on Days 5, 8, 11, and 13 post-hatch. We found that the rate and duration of begging of all nestlings in the CORT treated nests was greater than that of nestlings in food supplemented and control nests. In addition, the adults with CORT treated nestlings in their nest visited a greater number of times per hour and fed nestlings more frequently than did controls. Individual nestling behavior and data on nestling baseline and stress-induced CORT levels (collected on Day 11) will also be discussed.

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