I don't know if you witness the same behavior in your yard each year, but during the summer months I rarely see any scrub jays. However - almost as if they can read the calendar - when it gets to be September, I start seeing a lot of scrub jay activity in my yard.
Jays belong to a family of birds called corvids, and this family includes ravens, crows, nutcrackers and magpies. Some of the species in this family are notorious for the behavior of caching food. This behavior is observed in other bird species as well, including nuthatches and woodpeckers.
The biology of these species includes an instinct to 'harvest' food during times of plenty (fall) and store it for times of scarcity (winter). This behavior is very similar to what we see in some mammal species, such as squirrels, chipmunks and pack rats.
Each fall in the Central Highlands area, acorns from scrub oak trees and shrubs, and pinyon pine nuts from pinyon pine trees ripen and become accessible to food-caching animals. Scrub jays become hyper vigilant this time of year, scouring pinyon pine trees to harvest the new crop of nuts.
Another hoarder in our area is the acorn woodpecker. This species is famous for creating a granary, typically using a ponderosa pine tree snag as a place to store between forty and fifty thousand acorns in a single tree! From time to time, acorn woodpeckers even attempt to store their cache of acorns in structures, such as cedar-sided homes.
This natural instinct to store food sustains these non-migratory, permanent resident species, making it possible for them to stay here and avoid the effort of migrating. It is fascinating how birds know what kinds of food to harvest and how to store it so they can retrieve it during a time of need.
Unwittingly, birds that cache food also act as a seed and nut dispersal agent, as they will frequently bury their stash slightly under the surface of the soil with the intention of retrieving it later. Of course, they don't always re-find every seed or nut they store. Thus, they are ensuring the perpetuation of the species of trees and shrubs that produces the food upon which their very existence is dependent - ensuring a continuous food source for future generations! Talk about a bunch of bird brains!
Many of our customers who offer raw, unsalted peanuts in the shell to the wild birds in their yards find evidence of this caching behavior. Jays love peanuts, and will hastily bury them under leaf litter and cover them with leaves and twigs. Jays will also store whole sunflower seeds (in the shell).
Interestingly, only seeds stored in a shell have a long 'shelf-life,' and remain viable for years to come. These stored seeds will sometimes germinate and grow plants that will in turn produce the food needed by future generations of birds.
As you spend time in your yard this fall, you will no doubt witness the frenetic hustle of scrub jays to find and save seeds and nuts for the winter months ahead. It is another example of the wonder of nature.
A quick reminder - the entire month of September is the submission period for the Jay's Bird Barn (now The Lookout) Annual Wild Bird Photography Contest. The event is free and open to the public and I invite you to participate. For submission guidelines, check out the Jay's Bird Barn (now The Lookout) website. The exhibit opens to the public for voting on Tuesday, October 1st, as part of our Annual Fall Seed Sale and Anniversary Celebration.
Until next week, Happy Birding!