PARENT SESSION
Contributed Oral Session 126: Mammal Ecology: Management, Reproduction, and Food Webs
Thursday, August 11, 8:00 AM - 11:30 AM, Meeting Room 524 C, Level 5, Palais des congrès de Montréal

Reproductive investment of captive female striped skunks (Mephitis mephitis).

Quirk, Travis¹, Lariviere, Serge¹, Chivers, Douglas¹, ¹ Department of Biology, Saskatoon, SK., Canada

ABSTRACT- Striped skunks in northern climates accumulate large amounts of body fat in order to survive the period of winter inactivity and food scarcity. Mating occurs during the winter period (approximately March 15) in the confined space of the winter den and young are born in early to mid May. During this period of inactivity female skunks rely solely on their fat reserves for energy. These fat reserves are not only important for survival but reproduction as well. Pregnancy rates, date of parturition, litter size, total litter mass, average mass of offspring and sex ratio could potentially all be influenced by body fat levels from the previous fall. Captive female skunks were given access to males throughout the entire winter period in communal pens of multiple females and a single male, simulating natural conditions. Data on offspring and litter characteristics was recorded 5 days after the birth of the young. Fall body condition (defined as the percentage of body fat) was found to influence pregnancy rates and average mass of offspring. Percentage of total body fat lost over winter influenced parturition date. Age of mother also influenced fall body condition and offspring sex ratios indicating that there may be alternate strategies employed between the age classes. Female striped skunks may maximize their fitness by fine tuning reproductive effort according to their available reproductive investment.

Key words: Mephitis mephitis, maternal investment, reproduction