Physiological Stress Responses, Fecal Marking Behavior, and Reproduction in Wild European Pine Martens (Martes martes)

The relationship among physiological stress responses, fecal marking behavior, and reproduction in male and female European pine martens was investigated. Between July 2004 and June 2007, 145 fresh fecal samples were collected in a protected area of northwest Spain. Fecal DNA was used for specific identification by using the polymerase chain reaction-restriction fragment length polymorphism technique. Glucocorticoids (cortisol) and sex steroid hormones (P, progesterone; E, estradiol; T, testosterone) were quantified by enzyme immunoassays. Sex was assigned according to concentrations of T+P+E and the T/P ratio. Fecal cortisol concentrations were higher in males than in females. Feces with a presumptive marking function (on conspicuous substrates, above ground level, and/or in latrines) had higher mean levels of cortisol than those that were on inconspicuous substrates and/or at ground level, for both males and females. Fecal mark density was highest in spring, when mean levels of fecal cortisol were more elevated. Therefore, the higher physiological stress levels in females could be due to female physiological state (late-term pregnancy and lactation), competition for resources connected to birth, or food resources for offspring rearing. In males, the increase could be due to higher male competition for access to females during pro-estrus and estrus. Our results suggest that scent marking in European pine martens is related to reproduction and is involved in intersexual and intrasexual communication.