Australasian Science: Australia's authority on science since 1938

Male Snakes Worn Down by Mating Frenzy

A frenzied mating season is causing male snakes to die earlier and in worse condition than their female counterparts, who prioritise body maintenance over short-term reproductive success.

A University of Sydney-led study of red-sided garter snakes in Canada, published in Proceedings of the Royal Society B, found that:

  • males undertake energetic mating for 2–4 weeks per year;
  • males don’t eat and must compete with thousands of other males during the mating season;
  • females stayed at the orgy site for as little as 1 day, compared with up to 21 days for males; and
  • snakes hibernate underground for 8 months in their communal dens and emerge en masse in spring to form large aggregations where males scramble to locate and mate with females.

Senior author Dr Christopher Friesen explained that the males made good use of the relatively short amount of time to procreate, having only 4 months a year to breed, feed and have babies. “Although we believe that all females mate every year, they only stay at the den sites for a short period of 1–3 days, much less than males, who remain at least a week and up to 21 days,” Friesen said.

“Females reproduce every other year, which depends on their stored fat/energy reserves. Our previous research has shown that females can store sperm for up to 15 months or more before she uses the sperm to fertilise her eggs.”

The paper reported: “The relationship between body condition and age differed strikingly between sexes, with females maintaining their body condition with age, while condition decreased with age in males.”

In addition to prioritising self-preservation over sex, the female garter snakes did not waste energy on looking after their babies postnatally, which reflects the parenting approach of other snakes.