Coincidentally on another list this magazine article was offered.
"... In a landmark study in Wisconsin, Stanley Temple, now professor emeritus of forest and wildlife ecology at the University of Wisconsin, and his colleagues radio-collared free-ranging rural cats, watched the animals' hunting behavior, and examined their stomach contents. [...] The study showed that each cat killed an average of 5.6 birds a year. With an estimated 1.4 million free-ranging rural cats just in Wisconsin, that's nearly 8 million birds. Moreover, these numbers are virtually certain to be underestimates because the researchers didn't count kills not directly observed. Plus, many more birds were probably killed than were eaten and thus were not detectable in the stomach contents: cats are hard-wired predators that hunt even when well fed."
And those were presumably just the well-fed domestic cats, not the feral cats in the forest. The article observed that "Biologists also have used the studies from Marra, Temple, and a number of others to estimate the total U.S. death toll for birds due to cat predation as more than a billion per year." Whereas the press release on the earthworm study, also in Wisconsin, said, "Earthworms TO BLAME for Decline ...". No mention of invasive cats anywhere. And the authors claim in their paper that, "earthworm invasions may pose a regional threat to Ovenbirds."
Probably it would be easier to control the cat problem than the earthworm problem? Just a thought. Test it out inside a predator-free refuge and see how those killer earthworms and the ground-nesting birds get along?
> -----Original Message-----
> From: annelida-bounces from oat.bio.indiana.edu [mailto:annelida-
>bounces from oat.bio.indiana.edu] On Behalf Of Geoff Read
> Sent: Friday, 9 March 2012 7:15 p.m.
> To: annelida from net.bio.net> Subject: [Annelida] The early worm gets the bird?
>> The early worm gets the bird? The earthworm empire strikes back?
>> Well, you decide. It's subtle. And correlation is not causation. Humankind is
> likely mostly to blame in the end.
>>http://www.sciencedaily.com/releases/2012/02/120229142225.htm>http://dx.doi.org/10.1007/s10980-012-9717-4>> Scott R. Loss, Gerald J. Niemi, Robert B. Blair. Invasions of non-native
> earthworms related to population declines of ground-nesting songbirds across a
> regional extent in northern hardwood forests of North America.
Please consider the environment before printing this email.
NIWA is the trading name of the National Institute of Water & Atmospheric Research Ltd.