Thursday 4 February 2010

Survival of the Fittest

On Tuesday afternoon, I ambled down to feed the fish in the koi pond. Just as I was approaching the bridge, my eye was caught by a bright flash that disappeared into the water lilies. A baby had survived!

This is great news in the Morgenrood household. From October, a new cycle in a fierce battle for survival begins in our koi pond. That’s when the koi spawn and Siegie and I start to scan the edges of the pond looking for baby fish. Last season was our best season ever. We counted at least 20 fingerlings by the end of summer, but only two or three have survived the year.

When we first renovated our pond, friends and family used to give us small koi as birthday or Christmas presents. But it soon became obvious that they were throwing money down the drain. Of at least ten koi gifts we’ve received, only one has lived to adulthood.

Besides the frogs and the adult koi, there are three kinds of birds that find our “koilets” irresistible. As summer advances, they regularly visit our pond to gaze lovingly into the depths.

First, there’s the giant kingfisher, which gives a loud cackle of triumph when it spots our pond. But when it lands on the bridge railing, which is way too low for a diving board, it’s forced to fly away frustrated.

Then there’s the heron, which likes to stand motionless in the shallows waiting to stab a large fishy snack as it comes into range. It skirts the edges of our pond and generally flies away in disgust when it realises the water is too deep. This year, however, we had trouble with our pump and the water was low. At least two of our prized three-year-olds fell victim to the heron.

Finally, there’s the reed cormorant, a bird of a different feather, so to speak. Because it needs neither shallow water nor a diving board, it finds our pond a perfect place to hunt for a meal. Any koi smaller than 15 centimetres is fair game for this streamlined swimmer that seems to be able to dart around underwater for agonising minutes.

In the past five years or so, only around eight koi born in our pond have managed to survive into the second year. While most were predominately black with splashes of red, some were completely orange or white with large patches red and black. Desperately, we hoped one of these beauties would survive, but bright coloured fish are more visible. Sure enough, they were picked off one by one until only the darkest remained.

So, although I don’t hold out much hope for the five-centimetre-long light-coloured youngster I spotted the other day, I’m still keeping my fingers crossed.

“Why don’t you put a net over the pond?” a friend suggested. But it’s more important for us to keep our garden as natural as possible. And to be honest, we rather like being able to boast that herons and reed cormorants visit our garden. We just wish we could train them to be slightly less efficient.