Stagnant water doesn’t seem to be harmful to whitetails.
QUESTION: I just read a tip about putting a kid’s plastic swimming pool out to help keep deer on property during droughts. My question is: how do you keep the water from becoming stagnant and full of mold, or does that matter for wildlife? — Ronny H.
ANSWER: I’m not sure about mold, but stagnant water will grow green algae over time. I haven’t found anything suggesting that drinking water from a stagnant pond can be harmful to deer. After all, they quite often drink from stagnant ponds, pools and puddles in the wild, particularly when water is scarce.
However, during times of drought, a water source will attract the midges that carry EHD. If your area is known for EHD outbreaks, you might consider spraying the mud around the pond/pool with permethrin, or adding beneficial bacteria to the water in the form of a mosquito dunk, available at most hardware or farm and feed stores. — Recent Ask the Biologist Question:
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