Department of Physics, Chemistry and Biology (IFM)

The studies among others, compared the habitat similarities in the two locations where the invertebrates were sampled. Renkonen index and Sorensen index were take into consideration the minimum proportion of all the frequencies distributions. This is an established procedure in understanding habitats complexity.

The fish gut content were analysed and this provided information about the predator fish of interest. Thus the choice of Perch as the predator fish was adequate. Again, gut content analysis is very fundamental in knowing the interactions between species in an ecosystem.

In the predation experiment, the handling time is a way of quantifying the cost and benefits in a predation -prey contest. In the experiment, it was shown that there was no significant difference between the handling time across the different prey types and size category. 

The predation for Asellus aquaticus was shortest and that of  Corixidae was highest. However , looking back on the gut content analysis it shows that  Corixidae was more in the gut.  It might be that the vegetation in the natural habitats has a role to play. Without vegetation and dark substrates Asellus aquaticus is likely to be more vulnerable  as shown in the experiment. Corixidae  is often seen dangling  between clear water and vegetation in the natural environment , thus likely to be more vulnerable in natural water.

It is suggested therefore, that multiple factors need to be consider in order to adequately account for the handling time in a predator - prey contest.