The references read like a who’s who list of the top zealots. They are anti-cat, wildlife advocates. And the Smithsonian is the one that hired Nico Dauphine to run her kitty cam project - she’s the one that was found guilty of poisoning food left out for feral cats at her apartment complex (cats in a managed TNR program).
They’ve just found a new way to inflate the numbers of birds and mammals cats kill.
This is Peter Marra’s research history: http://www.voxfelina.com/2011/03/catbirds-cats-and-scapegoats/
I prefer the UK wildlife conservation organisations. They actually read the science, and understand the problem of extrapolating cat predation studies from one area to state- or nationwide estimates:
What none of the predation studies takes into account (cat scat predation studies, stomach content predation studies, etc.) is whether the cats hunted the animal it ate, or whether the animal was dead - or sick or dying.
There are studies of cat predation in birds that clearly indicate cats more often than not hunt sick birds.
The astronomical figures of these reserachers alone raise questions of credibility. If the breeding population of North American landbirds is 4.9 billion, then the 1.4–3.7 billion mortalities reported by Loss et al. (which the authors argue throughout their paper is a conservative estimate) represent an astonishing 28.5–75.5 percent of the total population. That’s on top of the 21 percent Arnold and Zink attribute to collisions with towers and windows.
While some species are, unquestionably, on the verge of extinction, the entire population of North American landbirds most certainly is not
As hunters go, cats are superb, among nature’s best, but cats are opportunistic hunters and kill for food, and just for sport and play. They hunt and kill whether they are well fed or not, and whether for food or not. It’s just what cats do.