Many factors influence the numbers and size of bluegills in a particular lake. ?Among them are the relative sizes of the Largemouth Bass and Northern Pike populations. ?Consider this information from the DNR:?“Pike eat tremendous numbers of fish, but mostly suckers, minnows and perch. ?Whether because of the bluegill’s spiny rayed dish shape or its ability to take cover in thick weeds, pike do not eat enough bluegill to reduce their numbers.
Largemouth bass appear to be a different story. ?They feed heavily on bluegill and seem adept at ambushing sunfish in heavy weeds. ?Largemouth will feed on bluegill up to one-quarter their own length. ?Consequently, a promising way of controlling bluegill numbers is by maintaining great numbers of medium-sized bass.”
Overfishing may also be an important factor. ?Bluegill occur in two sub-species or varieties, one of which is significantly larger than the other. ?When males of the larger variety fertilize eggs on a spawning bed, they stick around to defend the nest. Males of the smaller variety typically fertilize eggs and head for deeper water, leaving the larger males to guard the nest. ?As a result, the larger males are an easy catch during the spawn and their genetic contribution to the population is quickly depleted.
What we can do to improve the fishery?
As hard as it may be, toss back the 6-7″+ bluegills and keep more of the 5″ fish. ?Overtime, this will help restore the population of the larger variety which are so fun to catch on light tackle. Reducing the population of smaller pike, < 24″, can also lead to larger bluegills because fewer pike means more food for largemouth bass which feed on smaller bluegills. ?That in turn leaves more food for the remaining bluegills leading to larger fish.