To better understand the situation we need to talk about sex...ground squirrel reproduction that is. Their mating system is officially called: polygynandrous. That means they are promiscuous litter critters that mate with up to 4 others. If you were wondering why you haven't seen them on their dates, it's because they copulate underground.
When ground squirrels emerge from hibernation the first thing on their mind is sex. Is it surprising that the males emerge a few weeks earlier than the females? They just can't wait. This is their big chance because the females only produce one litter per year. (I've heard from a few biologists that they sometimes mate again if they lose their litter, but I can't find that in writing.)
In California, breeding season runs from December - April. The further south, the sooner the ground squirrels start breeding. After 25-30 days gestation, the female has a litter of 1-15. Yes, you read it right...up to 15 ground squirrels! Fortunately for us and the female, they usually have 7-8. Could you imagine caring for 15 little rodents underground? It's bad enough dealing with 8 of them above ground.
The reason we are seeing an overabundance of destructive diggers now? After 6 weeks of growing up in their burrow, the litters are emerging from their nests. The young look like miniature lighter colored versions of the adults. Guess what happens next? At about 6 months of age, the young ground squirrels will move into old abandoned burrows or scatter off to new territory. Ground squirrels have been known to travel up to 5 miles to start a new colony.
After they find the best location for their burrow, most ground squirrels will then get ready for hibernation. Then they get to repeat the cycle all over again. Let's just hope that it isn't repeating on your land. Oh, and I forgot to mention that ground squirrels live up to 6 years in the wild.
If you want to talk about ground squirrels or discuss green solutions to dealing with their over-populations, email me at: firstname.lastname@example.org or visit: BurrowBlocker.com.