Nest Searching in Forest Ranch

4/25 A pair of American robins are jetting across my yard in unison all morning long. As stealthily as possible I move towards the northern terminus of their circuit and observe them adding pine needles to the early stages of a nest. The platform is in the fork of limb, app. 12’ above the ground and perhaps 6’ out from the trunk. It appears to be entirely made of pine needles.

4/26 Visiting the robin nest this afternoon I was surprised to find that it had doubled in size in the last 24 hours. The exterior shell of the nest is about 4” tall and from what I can tell the nest is perhaps 7” across.

After seeing a Steller’s jay return to the same cedar tree next to my front door repeatedly with small sticks, I stopped to watch it hop up from limb to limb to a fork about 70’ up. There was the wispy, loosely assembled beginning of a nest platform.

4/27 I patiently watched and followed a pair of Hutton’s vireos about 200 yards down the road from my property as they foraged among the live oaks. After a couple of wild goose chases I finally saw an unusual amount of ‘rustling’ around in the outer leaves of a small live oak overhanging the driveway of my neighbors - the Archer’s. A tentative platform perhaps 2.5” across of spider silk and moss marked the beginning of the vireo’s nest. The nest is placed out at the very end of the branches.

4/28 Today I watched a (presumed) male Bewick’s wren for signs of breeding/nesting behavior. The wren would sing from the tallest of the small pines in the center of a brushy portion of my easterly neighbor’s property. The bird would sing from app. 6-8’ in the pine on an exposed portion of the limb just inches from the trunk. He would sing about 10 x, each song app. 6-8 sec. apart. After this song display the bird would hop down through the branches and travel through shrubs app. 3’ from the ground, continually issuing single call notes. He would pause during this trek and call more frequently (and rapidly) from a thicket into which I could not see, then continue travelling. I did not see a second bird or any indication that he might be collecting food, nest material, or servicing a nest in any way.

Returning to the Hutton’s nest this afternoon I was astounded to see how much had been done (see photo), what had been a mere suggestion of a base yesterday had grown into a 3” tall by 3” wide cozy looking little wonder!

4/29/2009 Searched out a new song early this morning which turned out to be an alternate Nashville warbler song. This vocalization was a very simple “p-chee, p-chee, p-chee, p-chee, p-chee” sometimes with additional rapid chee notes tacked onto the end.

After returning from town app. 9 am I headed back over to where I had watched the Nashville warbler singing this morning. While I had been there earlier I had heard the repeated scolding PEEEK of black-headed grosbeak and I suspected nesting.

In the tall deciduous oak on our property I watched a female black-headed grosbeak feed through the leaves, adjacent to a bright male lazuli bunting. Within minutes the female flew into the dense cluster of trees and shrubs in front of me and began snapping off small twigs from the bushes. A male soon joined her in collecting twigs, singing quietly from time to time. I have not yet found where the nest is being constructed within this thicket but will return again to locate it.

Leaving the grosbeaks I walked up to the opposite side of my property onto that neighbors yard to check out the American Robin’s nest that had been built within the preceding few days. As I approached the robin pair flew a short distance from the tree they had been residing in (not the nest tree) to another set of pines and cedars where they proceeded to copulate 3-4 times. Afterwards the female preened for a couple of minutes while the male sat in the sun of another limb just 5’ from the nest. When the female flew into the nest the male departed, she then did a couple of slow turns around the nest, settling deeper and deeper into it until just the tip of her tail could be seen.