Fish are present where there is a suitable habitat for the species. Meaning the water must have the correct turbidity, salinity, temperature and pH as well as enough food, food being the main attraction.
They live in a wide variety of habitats, from swiftly flowing waters, to shallow swamps or open lakes.
They may be grouped ecologically according to their ways of life: benthic(bottom dwellers); pelagic (free swimming) or plantonic (floating, as in the larvae of of some species).
Littoral zone fishes live in the inshorewaters where enough sunlight penetrates for the growth of rooted green plants, limnetic fishes in offshore waters and profundal fishes in the dark waters beneath the well lit zone, within these communities.
Fishes have differentfeeding habits. They may be herbivores (feeding on plants), omnivores (feeding on plants and animals) and piscivores(specifically on other fishes), Detritivores ( feeding on bottom deposits) and predators (feeding on other animals).
Fishes therefore have an importantrole in the food web as thgey convert plants and invertrabets into food for higher organisms, such as eptiles, birds and mammals, including man.
Fish species preferring the warmer waters i(east flowing rivers in Southern Africa) include Yellow-fish, Tilapia, Eels, Tiger-fish, Mud-fish,Cat-fish, Barbs, Bream and even a few types of Gobies.
Hippos prefer the warmer water where temparature seldomnly drop to below 16 C in winter. Therefore the fishes with a preference for the warmer water will obviously share their habitat.
Hippos have quite many parasites, being ticks, intestinal worms and whatever.
Hippos feed mainly on land (out of the water) however the also feed on plant growing in the waters. They also defacate mainly in the water as this is where they spend most of their time.
The Hippo dung will create a certain environment attracting other species which may come and feed on the dung and the intestinal parasites, which in turn are hunted by the next part of the food chain.
An example being diatoms and invertibrates feed on the dung, which in turn attract Barbs and Ghielemientjies, which again attract and are hunted by the larger predators being Yellow and Tiger and Cat-fish and Eels. Of course of the dung will also be consumed by the detritus feeding species.
By clearing the waters from excessive plant growth it creates an area where free swimming species can hunt and live in cleaner waters.
The external parasites are taken by the predatory species being, Yellow and Mud and Cat-fish, Bream, Tilapia who also compete with turtles.
I have spent many hours on a bridge in Kruger just watching all the above happen, nature will never cease to be fascinating.
I participate because I care - CUSTOS NATURAE
Convenor of the AIKONA Group.
No to Hotels in and commercialization of our National Parks.
Done 141 visits to National Parks.
What a wonderful privilege.