Date: 8/3/17 8:39 am From: Ann Truesdale (via carolinabirds Mailing List) <carolinabirds...> Subject: Re: Pennies
A quick Internet search reveals: "Newer pennies are made mostly of zinc." Easy to find information on both copper and zinc toxicity, too. I'd guess if either of those heavy metals dissolve in sugar water sufficiently to inhibit mold or mildew, it could be a problem for the hummingbirds.
Incidentally, a problem occasionally encountered by veterinarians is heavy metal poisoning in dogs that have swallowed coins. Of course, the stomach contents are acidic, and sugar water is not.
Ann Truesdale (retired veterinarian) <anntrue...> Meggett, SC
On 8/3/2017 6:31 AM, Stu Gibeau wrote: > A friend told me he was putting a penny in his hummingbird feeders to keep the mildew down. Is this bad for the birds? I would think it's not good for them. Although there's not much copper in pennies anymore > > Stu Gibeau > Black Mountain, NC > > >