Which groups of prey are generally considered opportunistic rather than a dietary cornerstone for *Crotalus oreganus*?
Answer
Birds and amphibians
While the diet of the Western Rattlesnake is overwhelmingly dominated by small mammals, certain food sources are encountered and consumed only when the opportunity arises, rather than forming a consistent part of the overall caloric intake. These less frequent dietary inclusions are birds (especially those nesting on the ground) and their eggs, along with occasional small amphibians. These items are categorized as opportunistic because their availability is transient or geographically limited, meaning they do not represent a reliable cornerstone when compared to the year-round availability and energetic reward provided by mammalian prey.
Related Questions
What prey forms the foundation of the adult Western Rattlesnake's diet across most distribution?Which prey item is juvenile *C. oreganus* disproportionately likely to consume?What primary method does the Western Rattlesnake use to secure prey?After striking prey, what cues does the Western Rattlesnake use to track the animal?What significant ecological service does the Western Rattlesnake provide by consuming small mammals?Which prey item heavily features in drier, inland California diets versus cooler British Columbia diets?What physical state follows the consumption of a substantial meal for *Crotalus oreganus*?Why are juvenile Western Rattlesnakes initially concentrated on smaller ectotherms?Which groups of prey are generally considered opportunistic rather than a dietary cornerstone for *Crotalus oreganus*?What consequence is noted when *Crotalus oreganus* populations are removed from a local area?