San Diego Casino Reviews

Admin | January 16, 2012 | Comments Off

San Diego Casino Reviews

San Diego Casino Reviews

The remarkable ability of Mexican monarch butterflies, San Juan Capistrano swallows, and California gray whales to return to the exact same breeding grounds every year after migrating thousands of miles is a true wonder of nature. But no less wondrous to many coastal Californians is the annual nesting of resident, non-migratory, Anna's hummingbirds that build their nests in the exact same places year after year. This article reviews observations made for eight different Anna's hummingbird nests that were built in the same Tasmanian tree fern in San Diego, California from 2003-2009.

Nest Locations and Periods

The eight nests were not only built in the same tree but in the same part of the tree. Not exactly the same branch, because tree fern branches are continually replaced by newer sprouts. These branches are strong enough to support a nest and a few 3-4 gram hummingbirds (a nickel weighs about 5 grams) but not the weight of cats or other predators. Over the seven year period, six of the eight nests were established between the end of February and the beginning of March and one nest each was built on April 23 and May 22. A ninth nest was started on December 22 but was abandoned for unknown reasons before being completed.