Have you seen fish gulping air at the surface of your pond or lake? It’s not normal behavior, but could be observed from now through this fall. It’s a warning sign pond oxygen levels have dipped to dangerously low levels.
As water temperatures rise, a pond’s ability to retain oxygen declines. Dissolved oxygen may vary with high plankton levels, extended periods of still, overcast days, or a turnover. If the water column cannot respire to maintain healthy oxygen rates, fish resort to gasping on the surface. Without a quick response, a fish kill could result.
If you see such activity, begin immediate aeration. Raise an outboard motor prop near the surface and run it for an extended period to agitate, aerate, and circulate the water column. If you have a well, turn it on and adjust the fill line to move and splash the surface. Utilize a farm tractor implement that can provide paddle action to stir and mix air in the water. If you have a water pump, draft water from the pond and spray it with high pressure back across the surface.
Small ponds are most susceptible to oxygen depletion. Let’s visit about a response plan if such a dreaded event occurs at your treasured waters.