The story goes that someone imported English sparrows to control the insect population. Completely oblivious to the fact that the little birds eat seeds, not mosquitos. But wouldn’t there have been predators in place to control our native wrens and finches?
They do eat insects- in fact just about anything their little beaks can hold. Opportunistic feeders is the term.
Plenty of critters want to eat sparrows- Hawks (I have watched a Coppers hawk eat one), owls, cats, and many other things nab the eggs and young birds- racoons, ravens, etc.
But they breed so fast.
I was under the impression that house sparrows followed boats from Europe to the Americas. I can’t remember where I read that. I can’t imagine they’d be any better at eating mosquitoes than the native birds.
It was possibly a combo, but in North America deliberate introductions, were the primary culprit. Some potentially apocryphal like the goal of introducing every bird mentioned in Shakespeare. Some “practical” like the half-assed notion to control a variety of moth that was having an infestation that was defoliating Manhattan. Some just whimsical like the Shakespeare one, but more along the lines “let’s release these birds we like from back home.”
But yes, there are plenty of predators that eat house sparrows - they have no special immunities. I’ve literally seen with my own eyes a house sparrow getting snatched up by a suburban sharp-shinned hawk, so it happens. It’s just that they are very closely tied to human habitation which have a somewhat lower volume of bird predators (because people) other than stray/feral/free-roaming cats and they are very fecund.
Are we mixing sparrows and starlings? Those are the real pricks that up-ended a lot of other species’ places in the (pardon the pun) pecking order.
The Acclimitisation societies were complete arseholes - we had them here in Australia as well. They (and sole operating acclimitisers) have possibly caused more environmental damage and financial impact than mining. When we finally get that time machine and go back to kill Hitler, you know who I’m going to suggest goes on the list next?
May I borrow that time machine when you’re done with it? I’m gonna get the asshole(s) who introduced the Garden Snail to California.
The book Natural History of the Cincinnati Region by Stanley Hedeen describes efforts to introduce various bird species like sparrows and finches in the 1800s. I haven’t read it for a bit, but I recall that they had trouble getting populations established at first. They built bird houses for them in parks, or left bricks out of smokestacks, but eventually they got a critical mass. I think there was a native cliff swallow species that actually increased in population as the city grew because suddenly there were buildings and bridges they could build their mud nests on, but introduced starlings (?) eventually took over their nests. I do see cliff swallow nests under bridges nowadays so at least in tat particular niche there’s been some rebalancing.
All that said, the first European settlers to this part of Ohio described unfathomably large flocks of birds, enough so that they’d darken the sky. It’s not unlike the herds of bison farther out west. Destruction of crops because of the birds and insects was so extensive that we ended up engineering a new “normal” that’s so desiccated compared to pre-European settlement that we have no lived experience left of how nature was so many orders of magnitude “bigger” than we know now. So yes there were predators for native species, but it required huge swarms of insects to feed the huge swarms of birds and everything else up the chain.
I had a nesting pair of Coopers up the street from me for a few years and had to clear (ok, flick) sparrow parts off my car more than once and stopped bothering with feathers. I’m talking an entire bloody leg or wing. I also saw signs of pigeon kills but there aren’t as many of those around. Those could have been a cat or raccoon even but I think it was the hawks.
Edit: I also got to know the sparrows’ danger call, a sort of cheeercheeercheeeer cry that really gets the flock’s attention. Mine, too, I always look for the Big Bad that the birdie saw.
I was sunning in my back yard and a sparrow flew from our feeder. A hawk swooped in over it and grabbed it up without breaking stride.
Hey, while you’re back there, would you slap the asshole whole introduced ice plant to California.
Cool! My Ravens (one is very large) have made this area not safe for the Coopers Hawk.