Some Bird Nests

I’ve seen four Robin’s nests so far this spring.  Two in cedars, one in a white pine and this one anchored to my house.  The Robins are year-round residents and spend the winter months feeding on various fruits or searching the creek edges for various arthropods and worms.

This female completed her clutch at the usual four eggs.  She’s been sitting for a week now, so the eggs should be half way to hatching.

Ledges are often used as nest sites.  Robins also readily utilize an open platform type nest box.
 

Usually the nest is higher than just a couple of feet above the ground.  I’m hoping this one doesn’t attract any passing predators.  The Robin nest is in close proximity to a Phoebe nest on a platform showing in the upper left corner of the photo.

The Phoebe chicks are already well developed.  I installed this nest platform specifically for the Phoebes in an attempt to keep them from nesting on the porch.  Porch nests almost always failed, usually because some unexpected late night visitor spooked the birds from the nest and the young succumbed to exposure overnight.  The Phoebes now raise at least one family each year on this platform.

The Wild Turkey nest I showed a couple of weeks ago has been plundered by some predator with a taste for eggs.  I have been purposely staying away from the nest so as not to leave a scent trail to be followed by hungry mammals.  A broken egg on the nearby walking trail was evidence of what had happened and the disturbed nest was clearly visible from a distance.

I’ve seen Opossums, Skunks and Crows do this type of damage to eggs.  Those three species are all common here.  This is why the turkey lays so many eggs.  It only takes a small percentage of successful nests to sustain the population.

The nest boxes are doing a brisk business.  Out of a dozen boxes, only one held a Bluebird nest.  Since I see several Bluebird pairs around the field, I assume some are nesting in natural cavities.

Tree Swallows occupy the majority of the boxes.  Twenty-five years ago, it was uncommon to see a nesting pair of Tree Swallows.  Bluebirds dominated the boxes at that time.

Feathers are used to line the Tree Swallow nest.  Turkey feathers are becoming more common, but the majority seem to come from domesticated ducks and chickens.

A single nest box was unoccupied and this is the reason why.  Wasps will aggressively defend their nest site from intruding birds or photographer’s heads.

The empty box did offer a platform from which the Meadowlark could sing undisturbed.  This guy tried to sing from occupied boxes, but was driven away by the resident nesting pair every time.  I’m not sure if the birds were defending their nest site against an intruder or just being critical of the Meadowlark’s vocalizations.

Pipe Organ Wasp Nest

Most people have seen mud nests of the Pipe Organ Wasp, AKA Mud Dauber.  Around the home, the nests are most commonly constructed on a vertical wall or beam.  A location favored by female wasps at my house is on the front porch.  The porch provides plenty of wall surface for nest construction and a roof to keep the nests dry.

Nests are constructed by the female wasp, a shiny steel-blue creature with a long thin waist.  She makes hundreds of trips to haul in balls of mud to form into the tube shaped nests.  Once a tube is completed, the female carries in paralyzed spiders and stuffs them into the tube.  Periodically she’ll lay one egg among the spiders and seal that section of the tube shut with additional mud.  Inside each of these sealed chambers, a single wasp larva will feed on spiders until it is time to pupate.  They will overwinter in this fashion and emerge as adults next spring.

The tube is constructed as a long arched structure, similar to the design of a Quonset hut.  The house forms the flat floor and the nest walls are built by adding mud fingers running from the central line of the tube to the house.  Placement of the fingers progresses in an alternating fashion from side to side.  Color differences in the fingers show that the wasp may visit several different mud sources during the period of nest construction.

While doing some work to the barn roof, I dislodged several mud nests from the barn rafters.  I checked out the debris later to see if anything of interest could be found in the debris.  Most of the fallen nests were old.  The few fresh nests all contained the lozenge shaped cocoons in which the larvae will eventually pupate.  I set undamaged cocoons in a safe place where they have a chance of surviving the winter and hatching new wasps next spring.

This cocoon was damaged in the fall.  Inside was a wasp larva.  The larvae eat just about every bit of the spiders in their cells.  Debris left in the cell is just a bit of dust.

Some cocoons were very light weight, so I cracked them open to see what was inside.  Most were filled with debris with no signs of the larva.

Several were full of the shed skins of Carpet Beetle larvae.  Judging by the number of skins in each cocoon, the beetles must have flourished here.

There are always a few old mud nests on the porch, usually in the corners.  I’ll remove them when they reach the stage where they begin to crumble on their own, but it usually takes them a couple of years to reach that stage.  I think they’re kind of neat to look at.  They remind me of the Mesa Verde Cliff Dwellings.  They’re just smaller and easier to access. 

Upground Yellow Jacket Nest

This delicate little structure almost looks like one of the myriad species of fungi that are appearing this year, but if you were to pick it, you would find it not as benign as you might first suspect.

Inside the umbrella like shell is the beginning of a wasp nest. The queen has begun laying eggs, so it won’t be long before the colony really becomes active. As the colony grows, the cap will be enlarged to fully enclose the brood chambers. I believe this to be Vespula alascensis, but the descriptions and photos I’ve seen are of the workers and may not accurately describe the queen. I’ll recheck my identification if it reaches the point where workers are present.

I always say that all you have to do is step outside if you want to find something interesting. This nest is a perfect example. Well, I guess it’s perfect except for the fact that just above the front door to my house is not the ideal location for something that frightens most people. I really don’t mind if the resulting swarm chases people away, but I’d hate for them to scare away the UPS guy and if they buzzed my wife, I’d be in big trouble.

I took these pictures in the cool of the morning and the queen was content to stay in the nest and waggle antennae at me. In the heat of the afternoon she took a more defensive posture and took to the air whenever I came near.

Relocation of the nest is probably the best course of action. Normally, collecting a nest for relocation is accomplished during the night. In this case I can’t do that because there’s a nesting Phoebe just a few feet away and I don’t want to scare it off the eggs after dark. I went out a short while ago to make my capture and found the nest empty. The queen must be out foraging. I left my equipment by the door in anticipation of her return. It’ll be a good test of my reflexes to see if I can get a jar over her nest before she can take wing to defend her brood.