Feathers and Fuzz

one woman's cure for the empty-nester blues

Bluebird

Nesting Challenges: Cold and Hot Weather

by

2017 presented us with an unseasonably-warm February.  The Carolina Wrens and Eastern Bluebirds started nest-building and egg-laying very early.  Eggs are laid at the rate of one per day.  Female parents do not typically spend the night on the nest until all eggs have been laid -- the idea being to incubate all eggs an equal amount of time so all eggs will hatch about the same time.  For spring nesters, especially, this delayed-incubation comes with a risk -- an overnight cold-snap, before the female is sitting on the eggs overnight, can kill the embryos.

 

The Bluebird pair produced 3 eggs, but then their behavior indicated things were not going according to plan.  Soon the pair started bringing additional nesting material to bury the existing eggs.  The cold nights had killed the embryos.  The pair began the nesting process again -- this time successfully.

Bluebirds Bury Eggs
Wren Parent Leaves Nest in Morning

 

 

The Carolina Wrens had a different story.  The pair produced two eggs.  BOTH adults spent the night in the nest -- from the time the eggs were laid until the nestlings fledged.  I have never seen a male do this before, but somehow this pair knew that it would take the body heat of both parents to keep the embryos/nestlings alive.  (One of the two parents is shown leaving the nest in the photo.)

 

Birds producing eggs well-into July are presented with the opposite challenge.  Bird houses can be brutally hot -- even in April.  Like dogs, nestlings will pant when hot.  They will also align into an X-formation in the nest to allow maximum air circulation around their bodies.

BB Nestlings in Cooling-X
BB Nestlings in Cooling-X

We just won't go into the fans, umbrellas and sun-shades I may have employed on their behalf.

Up next ...

When a human follows the rules the birds did not write ...

Nesting Challenges: Location is Everything

by

Location Choices May Be Creative, But ...

If you have ever left your garage door open for a few hours in the spring or summer, you have probably encountered the Carolina Wren.  It is incredible how fast they can build a nest!!

I made the mistake of not using my BBQ grill for a few days during nesting season.  When I opened the grill cover, I found the two-story Wren Mansion pictured here.  I can't even begin to tell you how happy I was to find no eggs in the nest.  Sorry Mr. Wren -- I win this territory dispute -- move on!

Wren Next Inside BBQ Grill
Wrens in a Box

Wrens in a Box

When I said "Move on!", I did not mean for you to move into this bamboo box I used for concealing minor electrical connections by the hot tub!  Really, Mr. Wren?!  

I was too late this time -- the nest was full of eggs.  Unfortunately, the box sat on a 24" high table -- an easy target for snakes.  Out came an assortment of construction material.  The box ended up on a pole protected with a snake baffle -- just a couple feet from its original location.  It took momma Wren an hour or so, but soon she was tending to her nestlings.  They fledged successfully -- launching from the cut-out handle of the bamboo box they called home.

Lesson Learned:  Never turn your back on a Wren during nesting season!

 

And, now, I will tell you the story of the Bluebirds who discovered the "barn birdhouse" -- the house I didn't think would ever be used for nesting.  Silly me!

One afternoon, I saw the Bluebird pair coming in/out of this decorative house.  I checked it out and, sure enough, they had an active nest.  The issue was:  With the house sitting directly on a deck floor, it was an easy target for snakes and other predators.  I had just been through a rough summer of nest predation and was not about to lose another nest to predators -- snake or flying squirrel!!

BB Barn Before Relocation

Bluebirds Move Into Barn House

 

So ... like the wrens in a box ... the "barn birdhouse" got mounted on a pole protected by a snake baffle.  I struggled with how I could protect the house from flying squirrels.  I came up with a design for a hinged, mesh door to cover the THREE holes in the barn house.  I'm sure I should not admit this -- but every night at dusk (after the parent Bluebirds left the nestlings for the night), I would go close AND LOCK the door.  I set an alarm and, every morning at dawn, I opened the door.  (I won't mention the fan I hauled out to blow cool air into the house during the brutal July/August temps.)

BB Barn Door Closed
BB Barn Door Closed

 

Crazy or not, these Bluebird nestlings (count them 1-2-3) became fledglings.

Triplet Nestlings to Fledglings