Hello, I am so glad I found this web site. There is so much great information. My ? is: I have a pond that is about 1 year old. I filled the pond from a near by creek/river with a pump and it stayed completly full until this summer. We had very little rain this summer but I also noticed a lot of crawl dad holes in the bank. I was wondering if they ( crawl dads) can cause ponds to leak. I pumped my pond back to full and in the past week it has dropped about 6 inches. We have had cool weather and some rain. I do have a bottom based aeration system in place.

Any info would be great.
Thanks

If your pond was built in porous soils, then lined with clay, crawfish can burrow through clay, and cause a leak. If your pond was built in good clay soils, crawfish probably won't be a big issue in terms of creating leaks.
Try to quantify your leakage by pushing a measuring stick into the mud, then reading it every other day for a couple weeks. See how fast your water level drops. Compare that to humidity, and estimate natural evaporation. Then, you can figure out how much water you are losing. It may not be enough to worry with. But, you can figure it out, then decide what to do.