There’s no way I can say for sure that this year’s pair of bluebirds are the same “attractive young couple” who have been my seasonal neighbors for the past several years. Their dogged determination to stay with the old nest box in my backyard in spite of many challenges sure makes me think so. Bluebirds don’t often nest in urban settings unless there’s lots of open space, but they recently lost a major feeding area just north of our backyard fence. What had been a large undeveloped area two years ago is now a string of new homes around a cul-de-sac street. Other challenges were natural, and the kind that all nesting birds face. They included late springs that delayed the bug hatch the birds need to feed their young. There was competition for nest space by tenacious and feisty other birds like house sparrows and house wrens. There were violent thunder and hail storms.
The originally tentative and shy pair of bluebirds coped with these challenges and became more mature and capable. They lost a couple of their nests to wrens who sneaked in and pierced their eggs while they were away feeding or chasing other competitors. I watched the male aggressively chase sparrows, wrens and even much larger (and meaner) starlings all spring, and was confident that he had the competition subdued by the time his mate began incubating five eggs. I unfortunately underestimated how determined a male wren can be. I checked the bluebird nest earlier this week, expecting to find newly hatched nestlings and found only one egg. It was pierced with the characteristic tiny hole made by a wren who had thrown the other four eggs from the nest.
More challenges are the only sure thing in nature! Though saddened by the loss of this year’s first bluebird nest, I am hopeful for their next nest attempt. They have chosen an open box just west of our home and built their new nest. I had a running battle with house sparrows in that box for several weeks this spring. They kept building new nests every time I threw one out, until I finally set a mouse trap under their nest. They sprung it twice. Although it didn’t catch the sparrows, it scared them enough that they abandoned the box. I expect to see new bluebird eggs any day and hope to enjoy their beauty and song awhile longer.
The challenges are far from over, though. Wrens are still in the neighborhood. Added to that is a pretty mama calico cat that decided to have her kittens under my firewood stack in the backyard. She’s just another in a series of feral (semi-wild) cats that have lived in our neighborhood over the years. Some were battle scarred old tomcats as fierce as any wild big cat, and others were young and sickly (likely abandoned by some one who no longer wanted them). Story County Animal Control in Nevada is overrun with cats, typically housing 120 to 160 of them at any given time. Some are eventually placed in homes as pets and others sometimes get sent to a few farms who want some cats to help keep the mice and rats in check. Those cats fortunate enough to be placed in new homes do so only after they get their vaccinations and are neutered.
Unfortunately, the demand for cats doesn’t keep up with the supply, and the supply can grow quickly since un-neutered feral cats breed at least twice a year. The problem of feral cats has been called a statewide cat crisis by vets and others who have to deal with it. Unvaccinated feral cats are reservoirs for disease and parasites that can spread to domestic animals and even humans. The threat of infectious bites and scratches by feral cats is greater than that posed by native wild animals. Most feral cats have intestinal worms and think an open child’s sandbox is a wonderful place to use as a latrine. They are hosts for fleas and ticks that also spread diseases. Native predators have always taken their share of young birds and animals, but now must compete with cats. Cats are one of the nation’s leading causes of bird deaths. Study after study indicates that cats kill many millions of birds every year. That includes well-fed house cats that are allowed to run free even — if they’re wearing a bell and are declawed! Some kindly folks feel sorry for the unwanted cats that lurk around their neighborhoods and feed them. Unfortunately, that only perpetuates the problem. Please, if you’re a cat lover — keep your cat indoors and don’t feed the neighborhood cats outdoors. Fewer free-ranging cats would be one less challenge for the birds to face.
Steve Lewka is a former director of Story County Conservation.