Biology population

Question

Rainbow smelt are a newly introduced species and are not native to Lake Winnipeg. They occupy the same areas of the lake as a native yellow perch species, and they tend to be more

aggressive. Suggest two limiting factors for yellow perch that are illustrated by this situation. Decide whether each limiting factor is density-dependent or density-independent.

Answer 1

Hello Jaclyn. From the prompt, there are two major limiting factors for the yellow perch. The first is increased competition for resources especially during early life when both species rely on zooplankton. The second limiting factor is the Rainbow smelt’s aggression which is borderline predation. The smelt is voracious, especially towards smaller fish and it could drastically reduce the survivability of the Yellow perch. Both competition and aggression from the Rainbow smelt are dependent on the populations of the aggressor and the perch's population. Hence, both of these limiting factors are density-dependent.