Monday, 29 June 2015

PART III: Cats as killers... debate continues!

They haven't read the reports themselves.
Feral cats have helped push
33 birds to extinction worldwide.
Most of these on islands.
Yes. I read the reports. I read the fine print. Still, the bird biologists keep going on and on. They simply do not understand cats. I read the Blanchard 'report', which was not pure research, but a synthesis of research and created a formula to determine how many birds are killed by cats.
They are extrapolations based on cat owner self-reports, reported number of house cats and feral cats, individual cats tracked, and extrapolated data. They call it a 'stochastic model'.
The formula ignores the fact that birds fly. Cats do not. These sparrow are frequently on the 100m driveway. The cats can't even get close.

Song sparrow food fight from Jennifer Jilks on Vimeo.
Just beginning a walk, I gazed down the driveway, and spotted some sparrow. One stole a worm from another. One was feeding its partner, too! You can see that our driveway needs doing and I didn't have a tripod!

The formula ignores the fact that certain cats (depending upon the breed/genetics; their proclivities; where they live: their environment, their climate; their gender, and which tend to be hunters, many do not hunt in the way the tracked cats hunt. Our four cats are profoundly different.

Daisy heard this mouse in the snow,
waited for it and pounced.
House cats simply are not the cause of endangering species for those birds who are in our yards.

  • Most cats grab ground feeding birds, in cities, at feeders. 
  • Most cats are not on islands, where endangered species are at risk.
  • Most cats are NOT the voracious bird hunters they claim, based on cats they track who ARE hunters.  (Ten per day?! As if. They get bored.)
  • Most cats capture juncos, goldfinches, jays, sparrows, at winter feeders – or sick, or young birds. 
  • Many cats do not capture a lot of birds in forests, or wetlands, they fear being prey themselves.
This is what the study says specifically...
They barely notice birds in the trees,
lie these waxwings who were gathering nest materials
4' off the ground in the front yard over two days.
They know they cannot get to them
"Twenty-three species at risk in Canada (COSEWIC 2012) are among the potentially vulnerable species in Table 5; 
all of these birds nest on or close to the ground in open landscapes in southern Canada, two on islands. 
Only one (Barn Swallow, Hirundo rustica) is frequently present in urban and suburban landscapes. Predation by cats is mentioned as a concern in status reports or recovery plans for at least 10 of these species, though in no case are house cats listed as the primary threat to population viability."
The butterfly net works well,
Annabelle brought me two last week.

Daisy likes catch and release.
She gets bored, and they take off.
That's not what the study says...
 It does say:

PART I: Cats as Predators
PART II: Cats as Killers: Myths or true data?


Nancy J said...

Jennifer, there will always be someone who is so ready to theorise, and there are too many factors to take into account for a survey of this proportion. here, with all the cats we have had over the years, very few birds have been caught and killed. Maybe feral cats do more harm, but how would anyone know about that, as they cannot see, or records any data that way. I agree, birds do fly. Sending an email, surgery date came in the mail yesterday. Hugs., jean.

William Kendall said...

Cats do get a bad rap from certain quarters.

Yamini MacLean said...

Hari OM
...what Nancy said... and also that so much of this statistical stuff can be 'massaged' - which you don't need telling!!! YAM xx

Christine said...

interesting capture of that food fight Jenn, I had no idea what goes on!

Red said...

This is one of those situations where there is no middle ground. Tt's either one or the other when in reality it's somewhere in the middle.

Jennifer A. Jilks said...

You're right, Red. Feral cats on islands kill. If people continue to feed birds in summer, cats will be attracted. We have to work together. Yet, very few of any endangered species are harmed by city cats.