Introduction to some aquatic protozoa in Essex
The pond in Figure 1 is a typical Forest pond with many different environments that harbour a
multitude of plant and animal life both at the micro and macro level. The number of small ponds in
Essex has dwindled considerably over the last century with the advent of agricultural drainage, road
building and building of new housing estates.
Woodland freshwater ponds, teem with an amazing variety of microbial life. The pond in Figure 1 is
located in Epping Forest, approximately 10 miles from the centre of London. Such ponds contain
numerous ecological niches that result from variations in oxygen content, temperature, pH, mineral
composition, light intensity, nutrient availability and associated life forms. Each unique habitat is
populated by organisms selected through the evolutionary process of natural selection for
characteristics that ensure an optimal chance of survival in a particular environment. Microbes can,
by their quantity and species, be used to identify ecological niches and changes in environmental
variables, and to detect the presence of pollutants. As ponds undergo both seasonal and short-term
(rain, drought, water fowl etc) changes that impose selective pressures on the inhabitants, they offer
a rich opportunity for the study of a variety of ecological issues.
Examples of species to be found
Some examples of what can be seen at the micro-level are shown below with a short account of their
morphologies and ways of life.
Amoeba proteus
Figure 2. Amoeba proteus © Steve Durr
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Essex Naturalist (New Series) 18 (2001)