Baby Whistle Pigs

The first shot of some baby Whistle Pigs (Marmota monax) at this camera trap set.  Four of 'em, it appears.

According to a variety of sources summarized by Feldhammer et al. (2003), average litter size for this species hovers right around 4 to 5 individuals.

• Litter size of 4.8 (sample of five females) in Ontario.
• Litter size of 4.5 (sample of four) in Illinois
• Litter size of 4.3 (sample of seven) in New York.

At 33 days old, young emerge from the nest for the first time and they wean at 42 days (Ferron and Oullet, 1991).  After one week of age, mother-infant contact begins to decline, which culminates in no contact at the time of weaning (Barash 1974).

Breeding usually occurs immediately after emerging from hibernation.  Young are born after a gestation period of 28-33 days (reviewed by Feldhammer et al. 2003).

The litter size pictured above is within the norm.  Also, these little Whistlers were probably born in late April (around the 20th, or so), as a result of adult copulation in late March.  The first adult pig captured active and above ground on this camera was on March 7th...so copulation occurring shortly after this makes sense, given the timeline I've just laid out.

Regardless of all that, those babies are pretty cute.

Lots going on this time of year, and lots more to report!  Trying not to fall behind!  More to come soon.....



Literature Cited:

Barash, D.P. 1974. Mother-infant relations in captive woodchucks (Marmota monax). Animal Behavior 22:446-48.

Feldhammer, G.A., B.C. Thompson, and J.A. Chapman. 2003. Wild Mammals of North America: biology management and conservation (second edition). The Johns Hopkins University Press.

Ferron, J. and J. P. Ouellet. 1991. Physical and behavioral postnatal development of woodchucks (Marmota monax).  Canadian Journal of Zoology 69:1040-1047.