Countries that have had domestic and wild cats for millennia are mostly unaffected by domestic cats being outside, especially in urban areas where wildlife is overrun by vermin.
Yes, there are plenty of examples of cats causing issues, but only in locations where they were introduced and not where they are native. Australia is a good example, as domesticated cats have become a nuisance and bred in the wild. But then you look at what has happened since the cat population was culled, with the many videos of mice on farms. Removing them isn't a perfect solution, as they've been around long enough to become a part of the ecosystem and not just a destructive force.
I would also qualify this with; cats should be kept inside whilst in heat. Many of the issues caused by cats are due to owners letting their cats reproduce. Where cats have a good supply of food, naturally they will reproduce up to a balancing point with the available food. Many cat owners are unaware (or just don't care) about cats reproducing and the impact that has. Spaying/neutering is also a viable option if owners don't want to have to lock their cats in during their heat cycle - cats birthing can be traumatic for the mother, so this can be a major benefit. Similarly, male cats will mate with multiple females so neutering is many times more effective than spaying alone.
Spaying/neutering should be the default option, unless you have a specific wish to breed your cats, and then you should have a plan for it and do so responsibly.
We also know that of the millions of baby birds hatched each year, most will die before they reach breeding age. This is also quite natural, and each pair needs only to rear two young that survive to breeding age to replace themselves and maintain the population.
It is likely that most of the birds killed by cats would have died anyway from other causes before the next breeding season, so cats are unlikely to have a major impact on populations. If their predation was additional to these other causes of mortality, this might have a serious impact on bird populations.
Those bird species which have undergone the most serious population declines in the UK (such as skylarks, tree sparrows and corn buntings) rarely encounter cats, so cats cannot be causing their declines. Research shows that these declines are usually caused by habitat change or loss, particularly on farmland.
From https://www.rspb.org.uk/birds-and-wildlife/advice/gardening-...
Not in Europe, maybe new zealand. But in Europe we had/have wildcats until we destroyed the large forests. And nearly ever farmer depends on a cat to keep vermin's in check, if you have to keep your cat inside DONT BUY A CAT.
We know to do more research about the cat effect on that fauna instead to just repeat one preliminary study.
We need to know for example, if there is a percentage of those migrant birds allegedly chased by cats in US that just crashed against a window or were stunded by pesticides. The problem in that case is not the cat, is the glass pane, or the absence of trees.
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Second point. Some scientists hypothesize that Toxoplasmosis remain in the body alive for years and is a chronic disease. We should however take in mind that this is not the main current of thinking.
We know that parasites don't survive usually when end in the wrong host because immune response works "like this" and "like that" and because the temperature, organ structure or life cycle of the true host, matter for the parasite survival.
I can't see why Toxoplasma should behave different that the other ten thousands of cases, or why the immune system should make an excepcion here.
-> Were stunTed
Sleepy day, yawn.
https://www.rspb.org.uk/birds-and-wildlife/advice/gardening-...
"Those bird species which have undergone the most serious population declines in the UK (such as skylarks, tree sparrows and corn buntings) rarely encounter cats, so cats cannot be causing their declines. Research shows that these declines are usually caused by habitat change or loss, particularly on farmland."
I don't talk about street-cats, i talk about cats who can come and go as they wish.
BTW: Now i have a Dog and he can come a go as he wish...podengo mix...so half dog half cat.
When I walk about my 'hood I do see pet cats enjoying a time being outside, but it does not take much bad luck for their fortunes to turn rapidly, due to getting lost and deadly encounters with cars and coyotes.