When the large pond in the rear garden was first constructed it was dug deep enough so that I could take an occasional dip in it on a hot summer afternoon. Despite recommendations by pond references to the contrary, I stocked the pond with ten small, inexpensive koi and two goldfish that were transferred from one of the smaller ponds. I’ve little doubt that the concern about having fish in a swimming pond is justified, but I’ve never heard of any harm done from swimming in farm ponds that are inhabited by all manner of beasts, so I didn’t figure it would kill me.

The pond was designed with a rudimentary filtration system that has managed to keep the water clear enough to see the pond’s rocky bottom, and I’ve not been too worried, even though the fish have multiplied far beyond the number that I’m able to count. No, the problem is not that I ran out of fingers and toes, but koi and goldfish are unwilling to stay still to be counted, and in a pond of fourteen hundred square feet it’s difficult to get even a rough count while they’re swimming in every direction.

Finally, this year the abundance of fish has overwhelmed the capacity of the filtration and the water has been a bit murky, and occasionally a little green from algae growth. The formula for this is fairly simple. Nutrients from fish waste and typical decay of organic materials, plus sunlight, will result in algae growing, and without more sophisticated filtration there’s no sense in me worrying about it. In fact, I’ve never done anything more than float on an inflatable lounger a handful of days through the summer anyway, so it’s not a big deal to just declare that it’s now a koi pond, and give up on the swimming part.

In addition to fifty or sixty (or eighty) fish, there are frogs and more tadpoles than you can count, an occasional turtle, and a snake or two that regularly inhabit the pond. A variety of insects skim over the pond’s surface, and dozens of dragonflies now patrol the skies immediately above the water. More than once in past years I’ve shooed away geese that appeared intent on taking up residence. Two large farm ponds are within a stone’s throw, so I’ve never felt guilt that I was denying them shelter.

There are regularly dozens, and sometimes hundreds of geese on the farm pond just across the creek, and they often congregate in the road and on the neighbor’s front lawn. The mess isn’t too terribly bad, but I’d rather they stay there than come over into my garden. In recent weeks a Great Blue heron has spent more time in the shallow filtration area of the pond and peering down from branches in the swamp maples that overhang the garden than I’d prefer. The heron is there for one reason, and I’d prefer that my koi not be its evening meal, but it’s difficult to dissuade a hungry bird who’s spied a pond full of dinner sized fish.

Despite the profusion of wildlife, I was still hedging on declaring that the pond was no longer for swimming, until recent weeks when ducks moved in. At first, my wife saw them on the back patio, but they were apparently just exploring. And then, we began seeing them regularly in the koi pond. So, now there are fish, frogs (and tadpoles), turtles, snakes, and ducks, and at this point it seems more clear that I’m the intruder. The ducks come and go, and when my wife and I go near they hop out to hide in the bushes, so there’s still a doubt that they’re here to stay.

I much prefer the ducks to geese, though I don’t know why. They’re certainly quieter, and I don’t think I’d mind if they decided to stick around. Especially since the pond is now off limits to swimming.