Date of Award
Thesis open access
Status signals allow senders and receivers to minimize the costs of competition by minimizing the need for costly physical fights. While much research has focused on demonstrating that individuals respond to status signals in both breeding and non-breeding contexts, less is known about how the function of status signals may change as resource availability changes seasonally. In this thesis, I provide a basic review of status signaling in birds and report the results of an investigation on status signaling in the black-crested titmouse during different environmental conditions. The black-crested titmouse is a socially monogamous passerine that defends territories throughout the year. This species forms small family groups during the breeding and post-breeding season, which dissolve into mated pairs during the non-breeding and pre-breeding seasons. Using an array of supplemental seed-feeders outfitted with RFID technology, I investigated the relationship between the crest size of adult male titmice and their foraging behavior during the post- and pre-breeding seasons. I also investigated the effect of both crest size and dominance on an individual’s ability to maintain baseline foraging behavior after approximately half of the feeders were removed. I found that birds with larger crests had greater access and monopolization of feeders during the post-breeding season, but not the pre-breeding season. When the number of available feeders were reduced during the pre-breeding season, males that monopolized their most-used feeder the most during baseline, and males that had longer crests, reduced their access to the feeders relatively less than other birds. Taken together, these findings indicate that the crest is used to signal status, particularly during times of increased competition (i.e. due to seasonal fluctuation in resources or increased competition between family groups).
Queller, Philip, "Minimizing the cost of competition in the black-crested titmouse: status signaling, dominance, and foraging behavior" (2014). Biology Honors Theses. 15.