THE BATTLE OF HOUSE WRENS

MALE HOUSE WREN #1

This Spring and Summer has been an active time for wildlife here in Mt Gretna.

On April 1st, our first day back from Florida, we were greeted with the singing of wood frogs.  A bit later Mallards and Turkeys came calling.  A pair of Mallards were here for more than a month and frequently visited our bird feeders and water gardens in search of food.  They became quite tame as they grew used to our comings and goings.  I did not look for the nest, but I believe it was near our pond.  They appeared to have hatched their young sometime around Memorial Day when we were away.

One day we looked out our front window and were surprised to see a Turkey Gobbler and two hens prancing around.  Fred (our nephew) had seen them earlier during the winter.
The Gobbler moved on to an another area and we often have heard him calling.  However, one of the hens stayed behind and established a nest.  We would see her often scratching around in the leaves for insects and other tasty creatures.  Her nest appeared to be behind our guest house.

This year the animals that take the prize for most interesting are the House Wrens.  Usually when  the male House Wrens show up in the Spring they wreck havoc on all the other song birds that are trying to nest in bird boxes in our yard.  These "cute" little demons will go around and destroy other bird's nests, remove their eggs and even their chicks. Then they fill the box with sticks.  Not a "nice" little bird in human terms.

BLACK-CAPPED CHICKADEE CHICKS

However this year was different.  We had Black-Capped Chickadees nesting in two different boxes about 400 feet apart.  Both pair had established their nest and laid eggs when the male House Wrens arrived about May 1st.  Both sites had male House Wrens calling nearby and my fear was that they would destroy the Chickadees's nest, but to my pleasant surprise they did not.  Both pair of chickadees completed their nesting and had young fledge.

HOUSE WREN BOX OF STICKS

When the male House Wrens first showed up, I put up two new bird boxes hoping that might keep them from disturbing the Chickadees. It seemed to work. One of the boxes was immediately claimed by a male House Wren and he proceeded to fill the box with sticks.  He soon attracted a wife and they were in business. We will call him MHW #1.  This pair raised 5 chicks that fledged during the second week of June.

At about the time the young House Wrens left the nest, an interloper male House Wren

(MHW #2) showed up. He began calling on a second new box about 30 feet from the box of MHW #1.  This guy (MHW #2) immediately filled his box with sticks and was frantically calling all around it.  Meanwhile, the original resident, MHW #1 continued to call on his box.  During this time I observed frequent fights between the two males.  I could not really tell where the female was in all this.

Over the last couple of days I  have made some interesting observations.  On Sunday (6/21) I saw a female enter the box guarded  by MHW #2.  Tuesday (6/23) I checked that box  and discovered 3 tiny eggs.  Meanwhile MHW #1 continues to  call on his box, but his nest cavity is empty.  Conclusion:  The female House Wren left her original mate and has moved in with the interloper---MHW #2.

WOW.

Our human reaction is predictable. "MHW #2 stole the "wife" of MHW #1".  "She is a slut who will sleep with anybody."  "An example of infidelity in the bird world."  "Birds are as immoral as humans."

FEMALE ON FENCE, MHW #2 FLYING ABOVE

Actually fidelity in the world of songbirds is more like--- "What have you done for me lately."
When faced with a choice, the female had to weigh the qualities of the two males and  decide which one best suited her needs.  Since I always go on the hypothesis that The Fittest Survive, there must have been something about MHW #2 she liked.  Does she like him because he is young, has a loud song or was it the layout of the home he was offering?  We will never know.

You just never know what may be happening right in your own backyard.