Meal patterns and food intakes of ground squirrels during circannual cycles

Abstract

Meal patterns in ground squirrels (Spermophilus lateralis) were recorded repeatedly over the course of endogenous circannual body weight cycles, with most data coming from the weight-gain phase. No manipulations were made, and the conditions were kept as constant as possible. Meal patterns were related to the level of food intake at each observation period. When the animals ate more, the most noticeable change was an elevated meal frequency. There were also some increases in meal size and the rate of ingestion. Postprandial correlations were generally positive, but rather variable and did not increase significantly when the animals ate more. On average 57% of the total intake occurred during the light phase of the LD 12:12 cycle. No systematic changes in the diurnality of feeding were detected. The meal patterns of hibernators when they are spontaneously hyperphagic show some resemblance to those seen in animals given exogenous insulin.