Orangespotted sunfish

The orangespotted sunfish (Lepomis humilis) is a North American species of freshwater fish in the sunfish family (Centrarchidae) of order Centrarchiformes. These fish are widely distributed across the middle and eastern United States, from the Rocky Mountains to the east, from the Great Lakes south into the Gulf Coast. The orangespotted sunfish is ecologically unique and thrives in turbid, shallow systems that have few predators and low oxygen contents. The species prefers vegetated areas in sluggish backwaters or lakes, and can also be found in turbid rivers. The orangespotted sunfish can extend its range in lower-quality waters, which is not characteristic of other sunfish. Orangespotted sunfish vary in total length and age for different river basin originations, but can be found to live four to seven years, and recorded lengths are up to 15 cm (5.9 in).

Males make grunting noises to attract females to mate, and are known to nest in 'colonies' or aggregations. Spawning patterns are similar to those of other sunfish. Due to the wide distribution of this fish, the species is not endangered and management plans are almost nonexistent presently. The orangespotted sunfish has been introduced to many habitats, such as rivers in Florida, Alabama, Texas, Colorado, Michigan, and Canada.

Habitat

The orangespotted sunfish prefers to reside in shallow, silt-laden waters such as floodplain pools, or waters with fine substrates such as sand. As species of the fish age and develop, they explore new territories and expand their ecological limits through migration. The dominant prey of orangespotted sunfish includes insects, such as corixids and chironomids, zooplankton, other small invertebrates that live in the water column, and fish. Though orangespotted sunfish can be found in different parts of a lake, their prey items do not vary much throughout the lake compared to other sunfish species. If reared in an environment with altered prey availability, the species has been found to show phenotypic plasticity or morphological differences in response to this changed environmental condition. Certain prey types require different methods of prey capture, so as the orangespotted sunfish develop, their body can be more elongated with an angled snout, or more deep-bodied with a blunt snout, depending on the prey type.

Distribution

In North America, this species is common in many places; it ranges from the Great Lakes to Hudson Bay, from the Mississippi River down to the Gulf Coast and in the Colorado River from Alabama to Texas. Some studies find that, in general, orangespotted sunfish tend to live in turbid, long, large lakes, which is evident by its geographic distribution. The orangespotted sunfish is found in the Canard River near Ontario, Canada, though it is an introduced species. In Texas, this species has been introduced in the past as far south as the Rio Grande basin.