Every few years for reasons unknown to biologists, all the oak trees in a landscape produce a huge crop of acorns. This is called a mast year. In California, mast years are simultaneous among stands of blue oak throughout the state.
Some biologists think that a mast year is nature’s way of saturating the market with acorns. Even after, blue jays, squirrels, white tail deer, and wild turkeys have eaten their fill—some acorns are assured of survival. Others believe that mast years are related to particular weather conditions that favor acorn production.
Whatever their cause, mast years are important for wildlife. 2010 was a mast year for acorns in the Hudson Valley of New York State. Well fed white-tail deer and abundant white-footed mice were seen throughout the winter.
This year, 2012, has seen almost a complete failure of the acorn crop in the same region. Already, in mid-fall, white-tail deer are moving to less preferred meadow forage and invading neighborhood gardens.
“When a high quality food resource is in short supply, one may witness dominant behavior between species. This is called ‘the law of the jungle’ or ‘the might is right’ effect.”
Ray Winchcombe is a wildlife biologist at the Cary Institute of Ecosystem Studies…
“I witnessed this recently when I observed a mature, white-tailed buck lower his antlers and actually lunge at wild turkeys that were feeding into the area underneath the same tree that he was feeding. In contrast, during years when there’s an abundant food supply, it’s not unusual to see many different species co-mingling underneath the same trees and sharing the abundant food supply that’s been provided by Mother Nature.”
For wildlife, acorns are worth fighting for.
Photo, taken on September 26, 2009, courtesy of Riley Kaminer via Flickr.