Birds and Cats

The book I am currently reading, Upheaval: Turning Points for Nations in Crisis (2019) by Jared Diamond, had a statement that surprised me.  Talking about windmills for power production he noted that the windmills are estimated to kill an average of 45,000 birds and bats a year.  That seems like a lot of birds and bats. He then puts the number in perspective>  He notes that pet cats which are allowed to wander outdoors have been measured to kill an average of more than 300 birds per year per cat. You read that right, THREE HUNDRED a year.  

Feral Cats in Hawaii

Birds are important to our overall ecosystem, and, according to "National Geographic" (January 2018) our souls.  That is the why 2018 was the year of the bird in that magazine, noting the trails and tribulations they face.  Birds seem rather common, but many bird species have been killed off.  A "Smithsonian Magazine" article (dated Sept 20, 2016, and found online) references one scholarly paper which states that 33 extinctions of bird types are related to cats.  I think the study was mainly on islands, where birds are rather captive. Birds are important regardless if on an island, or mainland.  I suppose they may be more important for the small island ecosystem, not that birds are not important on the mainland.

Diamond goes on to say that the US cat population is estimated at 100 million, and hence that equates to 30 billion (yes, BILLION) birds lost to cats a year.   That Smithsonian article, which is a few years older than Diamond's book, says the number of cats in the US is 86 million, still a large number.  Cats, it says, are more popular as pets than dogs.  While all cats are blamed for the bird carnage, Smithsonian goes on to say that a quarter to a third of cats are outdoor cats, and they are the main murderers. The following story is relayed by the author of the Smithsonian article: Tibbles, a cat, traveled to New Zealand with her owner in 1894, and "there she single pawedly caused the extinction of the Stephen's Island wren. A small flightless bird found only in that part of the world." The article goes on to say that most pet cats, kill on average two animals per week (mammals and birds), quoting the Wildlife Society. The solution is to bring and keep cats indoors.  

Indigo Bunting

Cats get their own Broadway show, having humans dressed as that sneaky, snide animal, and floating around stage.  I only recall watching part, but urban stray and feral cats are involved, I think.  What do birds get?  they get the Birdman of Alcatraz, one of the most notorious criminals in the United States. Does this show where the nation's heart lies?  Robert Stroud, the Birdman of Alcatraz has a Wikipedia page, and there is a quote that says he was a '"first-rate ornithologist and author," but was an "extremely dangerous and menacing psychopath, disliked and distrusted by his jailers and fellow inmates."' The book and movie about Stroud shows him a much kinder light than many say he deserved.

Birdman of Alcatraz, R Stroud
US Govt photo from Wikipedia

The main issue is the non-owned stray and feral cats, however. Feral cats are basically wild animals and in some instances a human caretaker may feed them and watch over them, which Smithsonian says "subsidizes" them.  The subsidization allows the feral cat population to sore.  My step mother was a cat lover, but my dad was not, and she was one who subsidized feral cats seen around the large yard.  She was also a bird lover.  I always thought there was some incongruity in her two loves--cats and birds, but never explored it with her.  I recall going to the basement of the house and finding cat feces; I found out she let the cat in the basement during cold streaks. I think she may have had them neutered, probably to help protect the birds. Getting back to Diamond's number of 100 million, he may add in feral cats which are estimated to be 30 to 80 million in the US (if he adds in, he is obviously kind to the number). 

Feral cat advocates, and biologists agree that there are too many feral cats.  In high priority areas, the Smithsonian article quotes a specialist as saying, they must be trapped and never returned.  Trap and release elsewhere seems to move the problem somewhere else.  The Smithsonian article goes on to say that if they cannot be trapped other measures must be taken--be it select poison or hunters.  The trap, neuter, return method has been used in some cities, and which the feral cat advocates prefer.  However, many ecologists say the method is problematic as to be of some success it would require over 75% of cats in a colony to be sterilized and that does not happen.  Short term reductions in colony size, they say, is quickly reversed. One cat specialist Smithsonian interviewed says the TNR method is no solution at all.  He and others call for widespread removal and euthanasia. Of course, what would be the unintended consequences of ridding cities of the feral cats?  Would rodent populations, rats and mice in particular, get even larger than they exist today?

Baltimore Oriole
Taken through a screen, sorry about lack of clarity to photo

Australia hopes to kill two million cats per year using robots, lasers and poison. New Zealand has "mass warfare on possums, stoats and weasels in a bid to save its beloved birds." Like many things, the US cannot agree on an approach, with advocacy groups on both sides.  Who ever knew there was an Alley Cat Association?  Incremental carnage of birds can cause real problems.  It did not take people long to kill off the passenger pigeon, and cats can already lay claim to have caused the extinction of  33 types of birds, and I suppose that number will only grow.  Personally, I am not a cat person, but if you own a cat, keep it indoors.  Thirty billion birds a year, is a lot of birds.  Or, perhaps, get a dog.