We have had a few mice, lizards, etc. drown in our jacuzzi and my daughter went and bought Frog Logs because we felt so awful. Our squirrels are welcome visitors along with the birds we feed and I feel your pain. I'm so sorry.

You have a kind heart and now you know how to prevent it.

Accelerated Community Oncology Research Network
Additive Congruential Random Number
AIDS Community Resource Network
Alliance to Conserve Old Richmond Neighborhoods
ARC (Australian Research Council) Communications Research Network
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Association of Community Organizations for Reform Now
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Aviation, Construction, Ordnance, Repair, Navy

Do you qualify as one of the above? If so, be afraid, VERY afraid!

I know how that feels to accidentally kill an animal. I accidentally killed some baby ducks of mine when I was about 10. Won't go into the sad tale, but am sympathetic as to how you're feeling....

with our turtle ponds. Had to build covers out of 1X2s and the 1/4" wire fencing. Total pain in the butt but no drownings since then. The smallest of outdoor creatures often grab our hearts and the thought of hurting them really sucks!

And I also felt terrible (although just yesterday, I spent $1200 to have new steel soffits installed, because the little jerks chewed through the vinyl ones)
I keep a sturdy branch inside the rain barrel now so anyone who falls in can climb out. As a gardener I am constantly battling the damage squirrels do, but I still don't want to hurt them.

and a little bird drowned. We hadn't thought of the pond as a hazard, but after we found the poor bird, we made some changes. We got a branch and fixed it so it was partly in the water and across the top of the pond. Later, we just covered the top of the pond with black cloth mesh and kept a shallow dish of water beside it. We didn't have any more losses.

In spite of trying to make our yards safe and welcoming, it's not possible to think of everything.

If you get a cover with holes, have them as small as possible, but not too small. Try to avoid something that will tangle small claws or talons, but not so big critters can get in.

Really sorry you went through such a sad incident.