I’ll keep this fairly short because I am not too sure how relevant it is to the cat/bird debate. There are two facts that relate to it which might interest some people. It concerns America because it concerns the coyote.
The coyote is an effective predator of outside cats. It is a reason why cats are kept inside. Consequently outside cats stay away from coyotes. No surprise there.
Cats stick to areas near their homes. Most cats don’t wander far. In America the domestic cat avoids the areas where coyotes live. A study employed camera traps (camera on trees etc. which fire automatically on detecting movement) to track the movements of wild animals and domestic cats in backyards, urban ‘woodlots’ and protected natural areas.
More than 50,000 photos were taken of coyotes and other wildlife such as deer, in natural protected areas. There were only 55 photos of domestic cats amongst them all.
In residential, urban areas where coyotes are also found, domestic cats confined themselves to residential yards. The cats are steering clear of coyotes. Domestic cats were 300 times more likely to be in a residential yard than in protected areas.
One of the protected area had no coyotes. In that area there were cats.
All this means that cats kill usually birds in urban areas and back yards. Does that have any impact on the statistics of cat predation on birds? Do certain species of birds favour the urban environment and are, therefore, more prone to being preyed upon by cats? I am not sure but it may be a significant.
The second little known fact about cats preying on birds is that city or urban birds have developed different behaviors to adapt to this environment. I guess this happened over centuries of being preyed upon by cats and other animals in urban areas.
Birds produce alarm calls more frequently. When captured birds are less aggressive and ‘remain more paralyzed’. They also lose more feathers.
I have not seen and can’t find the original study material for more detail but it would appear that urban birds have developed strategies to improve survival from predation by roaming domestic cats in the urban environment.
As birds are already towards the bottom of the list of favoured prey of the cat (see below), these strategies may well alter the cat-killing-bird statistics. I hope ornithologists take note.
Sources: LA Times referring to a study by Roland Kays, a zoologist at the North Carolina Museum of Natural Sciences and Science Daily referring to a study by Juan Diego Ibáñez-Álamo, researcher at the University of Granada (UGR) and Anders Pape Møller from Paris-Sud University (France).
P.S. My cat Gabriel is a good hunter and it worries me because I don’t like to see animals killed but I like to see natural cat behavior. I have to accept it. He has killed 3 birds.