Birds need help from cat owners

As related last week, domestic and feral cats are a huge threat to wildlife species, even in urban and suburban areas.

While loss of habitat and fragmentation due to human development is the leading cause of declining bird populations, The American Bird Conservancy states that invasive species including cats are the second most serious threat to bird numbers worldwide.

A study in Wichita, Kansas found 83 percent of the 41 study cats in an urban area killed birds, despite owners often not being aware of the predation. In fact, a de-clawed cat killed more animals than any other cat in the study.

A four-year Wisconsin study estimated that rural, free-roaming cats kill at least 7.8 million birds (and perhaps as many as 217 million) birds a year in that state. Suburban and urban felines would add to that total.

I've got to believe most cat-lovers also appreciate wildlife. They just need to be aware that when they release Fluffy out into the yard, the cat's natural instincts kick in and he or she becomes a killing machine.

Unfortunately, cats and habitat loss are not the only things making nesting season a dangerous proposition and endangering bird populations.

The duck nest I mentioned last week? Well, either a cat or raccoon killed the hen (I observed both feeding on the carcass) and consumed the seven or more eggs in the nest in the process - literally the day after I wrote last week's column.

Another factor has been the depressed fur market which has hurt fur prices, which has in turn prompted many to discontinue trapping and/or hunting raccoons.

That has led to increased raccoon and mink populations, animals that are also efficient predators of birds, especially those that nest on the ground. While fur prices have started to rebound slowly in recent years, we are still a long way from the heydays of 25 to 30 years ago when even a freshly-roadkilled raccoon could be sold for about $40 on the carcass to any one of several buyers in the area. Adjusting for inflation, that would be a tidy sum of money for most anyone today.

While raccoons are a naturally-occurring predator, human development has removed or displaced many of their larger enemies such as mountain lions. And with little incentive to hunt or trap them, coons are probably having an effect.

Also having a deleterious effect on this latter part of the nesting season was the excessive wind we experienced Wednesday and Thursday. Many nests were blown right out of trees, especially flimsy ones such as those of mourning doves, but also those mud-reinforced fortresses built by robins. The result is the same: destroyed eggs or injured or vulnerable nestlings.

Nothing we can do about that, but the good news is some birds still have time and will attempt to re-nest and pull off a successful hatch. That is if they don't run into one of their own brethren, a common yet despicable bird whose populations are increasing and now threatening the existence of many smaller birds due to their diabolical nesting behavior.

More on them nest week.