The muskrat skull variation of morphometric parameters to comparing primary and secondary introducants

Abstract

The muskrat (Ondatra zibethicus) is hunted animals for hunting trophies, fur and financial reasons in many countries. Morphometric parameters can vary in different populations of muskrat. The aim of this work was to perform morphometric parameters analysis of skulls of muskrat in Lithuania (secondary introducants) and to compare with primary introducants (Poland, Finland) with respect to sex and weight. According to Pankakoski et al. (1987), a total of 23 measurements were taken on each skull of muskrat. The skull measurements of secondary introducants (Lithuania) females were mostly larger than those of males (p < 0.05). But the muksrat skulls were longer and wider in males than in females of primary introducants (Finland and Poland). The mean values of measurements on condylobasal length (CL), braincase length (BL) and weight (BW) showed that were higher in Finnish and Polish than in Lithuanian populations of muskrat (p < 0.05). These can depend on adataptive changes: habitat quality, diet and others. The strong relationship between muskrat body weight and skull length were determined in Lithuania (r=0.72, p<0.001).