Health parameters and sexual signalling in yearling black grouse males (Tetrao tetrix)

Content Provider	Semantic Scholar
Author	Häsä, Laura
Copyright Year	2006
Abstract	In many species, male mating success is determined through female choice and male-male competition over females. Besides these factors, there are also differences in individual male investment to sexual signalling due to quality differences between males. In this study I investigated the effect of male condition on reproductive effort in yearling black grouse males (Tetrao tetrix). To discover male traits affecting reproductive effort, morphological traits, ornamentation and condition of 191 young black grouse males were studied and males’ mating success and lekking behaviour were recorded. Males, which were present in leks, differed from absent individuals in plasma immunoglobulin concentration, hematocrit, the number of microfilaria parasites and lyre asymmetry. Lek activity varied between males that attended the lek, but only hematocrit explained these differences. Activity on the lek improved mating success in yearling males and active males tended to achieve more central territories than passive males. Active and passive juveniles did not differ in the number of parasites, immunocompetence or ornamentation. My results indicate, that health parameters affects whether yearling males are present in lek or not, since males in poor condition are dead or dispersed to other areas before the lekking season in spring. Instead, there were no significant differences among lekking yearling males in health factors in relation their lekking activity in this cohort.
File Format	PDF HTM / HTML
Alternate Webpage(s)	https://jyx.jyu.fi/bitstream/handle/123456789/7246/URN_NBN_fi_jyu-2006453.pdf?sequence=1
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article