We recently had a question from a concerned follower:
Question: “This morning I just discovered 20 dead tadpoles at the edge of my backyard vernal pool. They appear to be green frogs but I can’t say for sure. I also found 3 live ones swimming around them. Also 4 full grown green frogs hopping at the edge of this area. This vernal pool is about 3ft deep in the middle and is so large that it usually is not dry until Sept 1. It’s about 40 ft in diameter. I have been watching over this pool for 20 years and I have never seen a die-off before. Any advice? What can I do? Can I test the water or the tads for ranavirus or pollution? Is there a vernal pool expert in my area that could help? – Johanna”

Answer: “Ranavirus is likely but the good news is it may not happen again next year. Really there is nothing you can do but be sure no fertilizers or pesticides are running off into your pool. If your pool dries down every year, there should not be green frog tadpoles in it as they need permanent water.

Check the bodies on the underside to see if you see hemorrhages or bloating. I don’t know any experts in your area.

Click below for a couple of papers our lab has done on diseases in pools.

Thank you for your stewardship or your pool. – Aram Calhoun”