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Food color can be indicative of specific nutrients, and thus discrimination based on color can be a valuable foraging behavior. Several bird and fish species with carotenoid-based body ornamentation show color preferences for presumably carotenoid-rich red and orange foods. However, little is known within species about whether or not individuals with (or growing) more colorful ornaments show stronger food-color preferences than those with drabber coloration. Here, we examine food color preferences in house finches (Carpodacus mexicanus) ‐ a species with sexually dichromatic and selected carotenoid coloration ‐ as a function of sex and plumage coloration during molt. We captured wild, molting juvenile house finches over 4 wk in late summer ⁄early fall, quantified the color and size of plumage ornaments being developed in males, and determined food color preference in captivity by presenting individuals with dyed sunflower chips (red, orange, yellow, and green). On average, finches showed an aversion to yellow-dyed chips and a preference for red- and green-colored chips. We found no significant difference between male and female preferences for specific food colors, and food color preference was not significantly related to male plumage ornamentation. However, we did find that redder birds demonstrated a higher degree of food selectivity, measured as the proportion of their preferred food color consumed. These results suggest that food color is not a major factor determining food choice in molting house finches, but that there still may be aspects of foraging behavior that are linked to the development of colorful plumage.

Florida scrub-jays are cooperative breeders that live in family groups consisting of a breeding pair, often with several non-breeding helpers. Florida scrub-jays cache food by scatter-hoarding items for later consumption. Within family groups, members have the opportunity to observe and pilfer the caches of other members. We observed jays harvesting experimentally provisioned peanuts alone and in the presence of other family members, to determine whether jays modify their food-handling behavior relative to social context. Non-breeding helpers were less likely to cache in the presence of the dominant male breeder than when alone and all jays tended to cache out of sight when observed by another jay. These changes in caching behavior are consistent with cache protection strategies employed by other species. However, the adaptive value of such cache protection within a sedentary cooperatively breeding family group on a year-round territory is unclear.