Sunday, November 14, 2010

Birds Move Trees

I was loading seed into a car at the Wild Birds Unlimited - East Lansing store and a ginko leaf blew across my shoe. Now where did that come from? I haven’t noticed any Ginko trees in the area. It may have blown miles.

Leaves are carried easily by the winds, but how can the seed of a tree like an acorn move away from its parent plant to germinate. These tree seeds need a little help to take flight and travel.


Blue Jay storing seeds in his esophagus

A single blue jay can cache or hide as many as 5,000 acorns up to 2.5 miles from their original source and retrieve them when needed. They can do this by carrying several nuts at one time in their esophagus.

The esophagus is a tube that connects the mouth and the stomach. It can also help store food for a short time through a temporary distension for certain birds like the nut eating Blue Jays, fruit eating Cedar Waxwings, fish-eating species and birds of prey.

Wild Birds Unlimied Whole Peanut Wreath
Blue Jays eat fruit, nuts, berries, seeds, and suet. At the feeder their first choice would be peanuts in the shell. In the wild, blue jays eat lots of different foods. Though they are primarily vegetarian they also will eat caterpillars, beetles and other small bugs. Rarely do they eat eggs and nestlings.

This behavior of burying seeds has greatly helped with the range expansion of many oak species. The rapid northward dispersal of oaks after the ice age may have resulted from the northern transport of acorns by Jays.

In one research study, 50 Blue Jays were observed selecting and caching 150,000 acorns over a period of 28 days. Each bird cached a total of 3,000 acorns by selecting and hiding an average of 107 acorns per day.

No comments:

Post a Comment