Sensory ecology and behavioural flexibility of predatory bats.
Published: 2005
Language: eng
Number of pages: 174
Description: In chapter five, I test the prediction that relative brain size is positively correlated with behavioural flexibility in 59 predatory bats representing 11 of the 15 extant families of bats which include predatory species. Before and after controlling for the potentially confounding effects of phylogenetic inertia, the results show a positive correlation between relative brain volume and behavioural flexibility, suggesting that relatively larger brains, though costly, are advantageous because they confer the ability to use multiple foraging strategies.Here I report on one comparative and three experimental studies addressing the use of auditory and other sensory information in predatory bats when taking prey from surfaces (substrate-gleaning) and airborne prey (aerially hawking) under conditions similar to those found in nature.In chapter three, I test the prediction that during aerial and gleaning attacks on dogbane tiger moths, Cycnia tenera, which have been argued to use visual and acoustic signals to advertise toxicity, northern long-eared bats use acoustic signals to discriminate airborne dogbane tiger moths and chemical signals to discriminate moths on surfaces. The results show that during aerial attacks the clicks produced by tiger moths act as a deterrent to bats, while tiger moths on surfaces were always attacked.In chapter four, I test the prediction that Indian false vampire bats,  Megaderma lyra, continue echolocating under moonlit conditions and over complex surfaces when hunting in unfamiliar space. The results show that regardless of light/surface conditions this bat echolocates using calls of similar design up to and throughout prey capture. In the context of past research, my results suggest that spatial memory, attention, and visual information should be considered in future studies, as they appear to interact differently in familiar versus unfamiliar spaces.In chapter two, I test the prediction that little brown bats,  Myotis lucifugus, and northern long-eared bats, M. septentrionalis , both glean and hawk prey. The results highlight the importance of integrating morphological and behavioural observations when determining foraging specialization in predators and suggest that the derived echolocation calls used by some bats when gleaning prey are functionally adaptive: given their acoustic properties, returning echoes will improve prey-background resolution.
Notes: Source: Dissertation Abstracts International, Volume: 66-10, Section: B, page: 5271.

Thesis (Ph.D.)--University of Toronto, 2005.

Electronic version licensed for access by U. of T. users.