The otter appears to be mainly eating freshwater mussels and possibly can not locate freshwater crabs in the Azolla . Waterfowl, such as black ducks, yellowbill ducks and Egyptian geese used to frequent the pool and now are only rarely observed if some of the pool is not covered. The fern must reduce the amount of area for the waterfowl to raise their young. Domestic animals have ventured onto the water fern in farming areas, possibly thinking that it was a solid sur face, and have drowned. One can only assume that this may happen to wildlife such as bushbuck and kudu.
Dragonflies quickly reappear when one is clearing the pool of the fern.
They are attracted by the reflection off the water surface. During summer they quickly start to mate and lay eggs, many of these eggs are laid on the water fern. The plankton is a very important food source for the young fish and without it the fish will starve. The water fern acts as a huge umbrella completely shading the riverine pools. The d ecaying plants sink to the bottom and cause a reduction in oxygen levels.