WEED EATERS: CUT TO THE CHASE Terry Babich Ponders Grass Carp I have been chasing grass carp in the Vaal dam for more than ten years now.
amount of food in the water for carp and cats by dropping more insect and seeds in the water.
These fish seem to have a bad reputation, maybe even more so than my usual quarry, the catfish. I don’t think it is all doom and gloom as so many seem to think. There is a lot of well known documentation about how they are used to maintain water quality in polluted dams. Years back municipalities used to stock them in their dams on a regular basis to maintain a good water quality.
The other way grass carp feed is to pull the roots of plants out of the ground. This method most definitely makes more food available for other fish species. Carp and cats can be seen feeding side by side with grass carp. Again, just bear in mind that this is only when water levels are on the rise and only when the grass has had chance to grow after the winter die back. If you had to check out these dams at the end of winter before the rains come you will become very much aware of the fact that they are primarily devoid of grass. So, again, a bit of a blank as far as competing for food is concerned. I don’t know of any other fish in our system that eats grass.
Let’s look at this only in terms of large dams that now have healthy populations of grass carp in them. So, to be clear, we are not talking rivers here. Rivers are a different kettle of fish all together. The biggest concern in many people’s minds may be that they eat all the grass that holds the food for other species of fish that don’t eat grass. The irony of this point of view is that Vaal Dam, Bloemhof, etc. only really have grass on rising water levels and there are normally no water grasses present in these dams. So not really a valid excuse. Are grass carp really competing for food sources? Doesn’t look like it. In all the years that I have been fishing these dams I can’t actually say that a lot of fish feed in the grass. Carp and cats, sure thing, but other species? You really don’t see them in the shallow water.
In the colder months or when the water hasn’t risen sufficiently to create feeding pasture for grass carp, what do they feed on and how is it that a river fish that are not suited for dam living and breeding are thriving in our dams? We need to start looking at what most people forget when it comes to grass carp feeding habits. My belief is that they also feed a lot on algae, something that is also well documented. This is a very, very important issue because our dams are so full of nitrates from sewage and farm fertiliser that washes into them that the levels of algae are unnaturally high. Global warming also aggravates this situation. This is where grass carp have played a huge role maintaining our water quality, or at least the little we still have.
Do grass carp therefore compete with carp and cats? I think it is actually the other way around. Grass carp pull and basically mow the grass down and it could be argued that by doing this they actually increase the www.saflyfishingmag.co.za
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