Fish

Fish are important indicators in Lake Okeechobee.

Black crappie are one of the most popular sport fisheries on Lake Okeechobee and provide important economic value to the region. They are sensitive to changes in vegetation and food; cultural eutrophication negatively impacts this community by shifting larval and juvenile macroinvertebrate prey-base from preferred taxa such as chironomids (non-biting midges) to one dominated by less preferred oligochaete (annelid worm) taxa.

Largemouth bass are the most popular sport fish on Lake Okeechobee, providing enormous economic benefits to the region. Four key factors have been found to influence the recruitment of bass into the adult population: availability of favorable spawning substrate; protection of nests from wind; availability of epiphytic invertebrates, forage fish, and other food resources; and protection from predators. These aspects are all directly related to the presence of a structurally complex vegetative community as fish habitat.

See the results for fish in Lake Okeechobee.

Fish and Fish Dynamics are an important indicator in the Southern Coastal Systems.

Three key fish species for the Southwest Coast sub-region are: Common Snook (Centropomis undecimalis), Florida Largemouth Bass (Micropterus salmoides floridae), and Sunfishes (genus Lepomis). The first two are economically-valuable recreational fisheries in the Everglades, while the third constitutes an important prey source for them. This long-term dataset shows that the abundance of these species is highly seasonal, with a quadrupling of the Snook and Bass abundance between the wet and dry seasons, and a 12-fold increase in the abundance of Sunfish prey in the dry season. These dry season increases in abundance are driven by a) the displacement of marsh inhabitants into the estuary upon marsh drying (the Bass and Sunfishes), and b) the upstream movement of estuarine residents (the Snook). Snook move upstream to take advantage of this seasonal prey pulse which occurs most years, and they partition with Bass. Catches of all 3 groups in our monitoring are negatively related to stage, such that more fish are caught at the lower stages of the dry season, showing this immigration and co-occurrence of predators and prey at the headwaters of the Shark river at the peak low flows of the dry season.

See the results for fish in the Southern Coastal Systems.

Photo credit: Jennifer Rehage.

How is it measured?

Lake Okeechobbe  

In Lake Okeechobee, Black Crappie and Largemouth Bass are monitored. There are two indicators for Black Crappie; age 1 and >=10 inches. There are two indicators for Largemouth Bass; age 1 and >=12 inches. The thresholds are based on the catch per unit effort.

Southern Coastal Systems, Southwest Coast

A desired condition was established for these coastal fishes by calculating a long-term average abundance over the 13 years of monitoring. The deviations from this long-term mean were evaluated across years for the 3 groups.