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or you are just eating up one random study the media went wild with because it made good headlines?

windows - https://www.sibleyguides.com/conservation/causes-of-bird-mor...

Habitat Loss, pesticides and other chemicals, then invasive species not just cats (including plants), then windows https://www.birdscanada.org/conserve-birds/major-threats-to-...

and i could go on. this will of course change with the country you are in, cats in a country like australia or small island are going to have a much different effect then NA/UK/EU and thus lots of organizations and scientists for these areas do not put cats as the number one cause because it really is not established fact.

I knew exactly what paper you were linking because it is always the one people trot out, as the only one making such wild claims with numbers that big from some imho wild assumptions.

There are others who also correctly pointed out that it is alarmist paper that needs to be taken with a large grain of salt: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9794845/

some of the choice quotes:

"both implied or were interpreted by others to indicate alarming predation of house cats on prey populations."

Churcher and Lawton (2) investigated predation by ca. 70 cats in one English village over a 1-year period, .... The authors estimated that 30% of the sparrow deaths in the village were due to cats, but stated that the village sparrow population was much higher than the average in other British villages. Although the authors were cautious in their interpretation, the media took off with alarming extrapolations of these very limited data across all of the UK."

"Loss et al. (3), .... stated that the magnitude of mortality in mainland areas was largely speculative. .... stated that un-owned cats (as opposed to owned pets) cause the majority of this mortality and concluded that free-ranging cats are likely to be the single greatest source of anthropogenic mortality for U.S. birds and mammals. However, most of the field studies in their literature review and in their data extrapolation have not taken the above-mentioned known facts about cat predatory behavior into account, .... Among the various studies they considered many lacked a correction for prey eaten or left when away from home, different methods of gut analysis, no control for habitat where the data were collected (suburban, city, farmland), or other causes of prey decimation (e.g., habitat destruction). "

"But the most serious criticism of all such studies is that none of them even mentions a rough estimate of the total population size of a prey species (supposedly being threatened by cat predation) or of the yearly reproduction and replacement of lost individuals. What good does it do to headline that “Cats kill up to 3.7 billion birds annually” if the estimated total population of birds in the USA is at a minimum 10 billion pairs breeding every year and that as many as 20 billion are in the country during the fall migratory season [US Fish and Wildlife Service (18), cited January 19, 2011]? Free-ranging cats might be taking about 10–15% of the population of birds annually, but that is not exceptional for a normal predator-prey relationship and is insufficient to eliminate a prey species. Further, estimates of the owned and non-owned free-ranging cat populations are just that–rough estimates."

"Fitzgerald (7) and with the addition of even more field studies (28) have countered that there is simply no evidence that free-ranging cats on the continents are the main cause of species disappearance (and biodiversity reduction) since there is usually a suite of predators utilizing the same prey species and other causes can be cited"



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