Foraging is a key aspect of a species’ ecology and decisions made while foraging affect fitness in many ways. Although much research has focused on snake foraging, only a handful of detailed studies have been conducted on free-ranging individuals, all on Crotalus horridus. We used fixed videography to collect data on free-ranging Northern Pacific Rattlesnake (Crotalus oreganus) behavior to qualitatively test predictions regarding interspecific differences in rattlesnake foraging behavior. We analyzed foraging behaviors based on encounter rates with prey and strike rates on prey, distances moved between consecutive ambush sites, residency time at each site, and poststrike behaviors. Snakes encountered approximately 4 prey/d, with California Ground Squirrels (Otospermophilus beecheyi) being encountered at much higher rates than other prey types. Crotalus oreganus typically did not remain at hunting sites for long durations compared with other species, and generally exhibited short distance movements (<10 m) to new sites. Snakes initiated strikes during 21% of all prey encounters, and 49% of these strikes were successful. Snakes were more likely to hold on to nonsquirrel prey than squirrels after a strike. When snakes struck and released prey, the distance prey fled after a strike was positively related to the time snakes spent locating the envenomated prey. Our findings indicate that variation in rattlesnake foraging behavior both within and between species might be driven largely by differences in habitat features, including prey abundance.

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