Movement patterns and foraging ecology of Gila monsters (Heloderma suspectum Cope) in northwestern Arizona
Nine Heloderma suspectum were observed between 1 April and 13 July 1979. In April and May, movements of Heloderma were associated with areas where eggs of ground nesting birds were most abundant. During June and July, Heloderma responded to decreasing egg availability by shifting their diets to small mammals and moving onto areas where these prey were most abundant. These shifts are adaptive as Heloderma continually exploit the most abundant prey. Lizards demonstrated a foraging strategy of rarely backtracking and consuming only an average of 46% of the eggs available at each nest. The number of eggs eaten per day by each lizard was positively correlated with lizard weight. Combinations of lizard satiation, reproduction,...