Big problem everywhere...
Not sure how Hawaii handles it, but similar to their to allowing snakes aboard...
Local park where I walk is a bird preserve, they do a decent job of trapping feral cats, once in a while one gets in... Then there are the do-gooders that leave food out for them, I trash it any time I find it...
Here at home, three or four cats roam at will, one in from the farm is a serious hunter, see him up in trees, waiting.. We used to put out bird seed, but the cats, leaping for the birds, knocked down the shrub below the feeder. Neighbor had a nice birdbath fountain, but it became obvious it was really a cat feeder, a continuous bird supply, so she took it out...
It's not the Canada Geese or Swans that have a problem, but all the other little guys... One of our doves ended up a pile of feathers the other day... Bummer...
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