HEMATOLOGIC, BIOCHEMICAL, AND ENDOCRINE CHARACTERISTICS OF BOBCATS DURING A PREY DECLINE IN SOUTHEASTERN IDAHO

We studied the hematology and blood chemistry of 33 adult bobcats (Fel is rufus) captured from 1982 through 1985 in southeastern Idaho during a decline in lagomorphs, their major prey. Our objectives were to rel ate blood physiology of bobcats to sex, season, and a decline in abund ance of black-tailed jackrabbits (Lepus californicus) and Nuttall's co ttontail rabbits (Sylvilagus nuttallii). Males had higher (P < 0.10) e rythrocyte counts (RBC) and hemoglobin levels (Hb) and lower (P < 0.10 ) insulin concentrations than females. Bobcats sampled during spring h ad higher (P < 0.10) mean corpuscular volume (MCV), mean corpuscular h emoglobin (MCH) and insulin levels, and lower (P < 0.10) Hb, packed ce ll volume (PCV), RBC, and cholesterol levels than bobcats captured in autumn. The decline in lagomorph prey abundance from 1982 to 1983 was reflected in bobcat blood by lower (P < 0.10) phosphorus and insulin l evels and higher (P < 0.10) Hb, RBC, and PCV. Progesterone levels in f emales reflected field results indicating that reproduction was curtai led when prey was scarce.