Wednesday, January 30, 2013

Study says cats kill more birds than wind turbines

Those who oppose wind turbines often cite bird deaths as a reason, noting incidences in which birds have flown into turbines and been killed en masse. But a Smithsonian Conservation Biology Institute study has found that wind turbines kill far fewer birds annually than an average house cat, Tim McDonnell of Mother Jones reports. (NPR photo)

The study, published today in the journal Nature Communications, found that cats kill about 12.3 billion mammals every year and about 2.4 billion birds. By comparison, wind turbines kill just 440,000 birds. Study authors write that "free-ranging cats . . . are likely the single greatest source of anthropogenic [human-caused] mortality for U.S. birds and mammals." (Read more)

Smithsonian animal ecologist Pete Marra told NPR's Veronique Lacapra that Americans own about 84 million cats, of which 40 to 70 percent are allowed outside. About 50 to 80 percent of those are actually hunters, so around 47 million cats, most of them feral, are killing prey every year. Researchers analyzed all available data to estimate about how many bird and small animals cats kill each year.

3 comments:

EJ said...

I have downloaded the study and reviewed it. I am an avid birdwatcher and very concerned about the decline in some songbird species, but this study is just bad science at its very worst. For instance, the figure on the number of feral cats in the US are not backed up by any evidence. As the authors admit: 'No precise estimate of the un-owned cat population exists
for the United States because obtaining such an estimate is cost
prohibitive, and feral un-owned cats are wary of humans and tend
to be solitary outside of urban areas." However, the validity of the conclusions of the study rests on multiplying predation data (also very questionable) by the estimates of feral cats. As far as I know, all such estimates are just wild guesses, pulled from thin air and not based on wildlife surveys. Let's get some real data before we start scapegoating cats!

EJ said...

I have downloaded the study and reviewed it. I am an avid birdwatcher and very concerned about the decline in some songbird species, but this study is just bad science at its very worst. For instance, the figure on the number of feral cats in the US are not backed up by any evidence. As the authors admit: 'No precise estimate of the un-owned cat population exists
for the United States because obtaining such an estimate is cost
prohibitive, and feral un-owned cats are wary of humans and tend
to be solitary outside of urban areas." However, the validity of the conclusions of the study rests on multiplying predation data (also very questionable) by the estimates of feral cats. As far as I know, all such estimates are just wild guesses, pulled from thin air and not based on wildlife surveys. Let's get some real data before we start scapegoating cats!

Michael P. McGuire said...

Songbirds = Indigenous species vital to the ecosystem.

Domestic cats = Invasive species detrimental to the ecosystem

Asian tree beetles have spread all through Mahopac Falls New York decimating Maple trees. What eats Asian tree beetles? Birds. What kills birds? Domestic cats that are descendants of animals brought here from The Fertile Crescent, that are let out by their owners. One invasive species gives rise to another. Domestic cats love the indoors. Let's keep them there. It is where they are the safest. That should be motivation enough for any cat owner that loves their pet.