Are birds, wildlife at risk drinking water from a Danville swimming pool?

DEAR JOAN: I notice that a variety of animals and birds drink from my swimming pool. Does the chlorine cause a problem for them? Do they have an instinctive reaction against drinking tainted water?

I don’t know how we could protect wildlife from the thousands of swimming pools in our county.

Lyn Arscott, Danville

DEAR LYN: Like a lot of things in life, it comes down to individuals doing what they can, which will collectively make a huge difference.

While drinking chlorinated water is not good for animals or humans, it depends on how chlorinated the water is and how much the animals drinks. Some animals might have instincts that would keep them from drinking heavily contaminated water, but when they are thirsty, all creatures tend to toss caution to the wind and drink deeply.

In the case of pool water, birds might be the most affected by chlorine, especially ducks and geese. As well as the toxicity factor, chlorine can irritate their skin.

Most common visitors in our yards, from squirrels to deer, are better able to deal with the chlorine, which can take about 12 hours to leave the body. Excessive consumption, however, can harm the kidneys.

The greater danger these animals face is not the chlorine in the water, but the water itself. A good many fall in while trying to bend down to get a drink, and as most pools have tiled or plastered sides as well as a lip that extends over the side of the pool, climbing out is not easily managed.

To make pools safer, keep chlorine levels low and install escape mechanisms for creatures that might tumble in — floating ramps for smaller animals to climb up and out of the pool and knotted nylon ropes dangling into the pool for the larger ones. Pool covers also are a good way to keep out unwanted swimmers, including pets. You also can provide an alternate source of clean drinking water, making the pool less tempting.

DEAR JOAN: I went to get the newspaper one morning this week and discovered a group of broken snail shells on the walk, all picked clean. I’ve seen this kind of evidence in other areas of my front yard but this morning, the shells were so numerous it really piqued my curiosity.

We have lots of lizards, but I’m leaning to opossums, although I’ve not seen one. I posted this question on Nextdoor, but all I got were guesses.

Barbara Thurston, Castro Valley

DEAR BARBARA: A great number of creatures rely on snails as part of their daily repasts, including birds, lizards, opossums, raccoons, rats and beetles, to name a few. Because you found the shells in the morning, we can eliminate birds and lizards. For the most part, they are inactive at night.