Right now you are breathing in oxygen. You
probably drink water when you’re thirsty, and eat food when you’re hungry. And it’s
highly likely you have some type of shelter to protect you from nature’s elements. Air,
water, food and shelter are basic survival needs for humans. Aquatic organisms have survival needs too.
Beside their need to reproduce for their very existence, many of them depend on one another
as part a natural food chain. For example, zooplankton may eat phytoplankton, gizzard
shad may eat zooplankton, and largemouth bass may eat gizzard shad. Yum Yum. But in order for this natural food chain to
function properly, a healthy population of each participating species is necessary. A
population is a group of individuals of one species who live in the same place at the
same time. And populations of different aquatic species which live within the same river,
coastal marsh or hill country stream can create a community. Does the system sound familiar?
In much the same way, we also create communities in our cities and towns. Only, in aquatic
environments there is much more interaction and interdependence between its residents. All aquatic plants and animals, including
fish, have adapted characteristics over millions of years that allow them to live in water.
Yet the challenge for each species is to find their niche, its role in the community, as
a resource in the overall food web.