Introduction

Carpiodes velifer, commonly known as the Highfin carpsucker, can be found throughout the Southeast and the Midwest United States but is most widely distributed in the Southeast. The Highfin carpsucker has been located as far north as upper Michigan, as far west as Nebraska, and in the deep south of Louisiana and Florida. Highfin carpsuckers are generally found in large to moderate sized rivers. They tend to stay in more shallow water than most carpsuckers and do not go in smaller streams like the Quillback carpsucker.
Highfins spawn from April through June, and in some states eggs have been found up until late August. In the third year of life this species becomes sexually mature. These fish migrate locally but are not considered a migrant species. Their diet includes an assortment of small crustaceans, protozoa, filamentous algae, and other aquatic invertebrates. Northern pike, muskellunge, walleye, and largemouth bass have been known to prey on the Highfin. However, humans are still the most significant predator that this species encounters.
In order for the Highfin to thrive there needs to be a specific monitoring plan for its habitat. In 2010, three mature Highfin carpsuckers were caught in the Apalachicola River, located in western Florida near the Georgia state line. This was the first confirmed existence of this species in this particular area. The small number of this otherwise abundant fish in surrounding states leads researchers to believe it is linked to fragmentation and overall habitat degradation of the Apalachicola River. Right now further studies are underway to determine the total number of Highfin carpsuckers in the Apalachicola River, as this data is necessary to decide the best management strategy.

Geographic Distribution

Highfin carpsuckers can be found throughout most of the Eastern part of the United States and partially west of the Mississippi River. They have a traditional temperate water distribution and are most commonly found between 46°North to 31°North latitude. The Highfin can inhabit waters all the way from South Dakota to Louisiana, but are not found in the Northeast portion of the United States. The Highfin can be found even more abundantly in the Mississippi basin and the Lake Michigan drainages as well as in adjacent rivers and drainages. The Highfin carpsucker has been introduced in the Santee River and along Cape Fear in North Carolina. This species is found in medium depth water (4 to 10 feet) usually in areas with a rocky gravel substrate.

Ecology

The Highfin carpsuckers diet consists of small crustaceans and other aquatic invertebrates such as crayfish and snails. This species prefers to feed in large to moderately sized rivers but usually stays closer to the bank than the open river channel. However, it is important to note that it is not common for the Highfin carpsucker to be found in very shallow water.
The Highfin carpsucker does not tolerate very much change in the water velocity and prefers to stay in moderate to swift currents. This species feeds and thrives in areas that have a consistent sandy or rocky gravel substrate. Siltation can cause a variety of problems for this species and some of the other species with which the Highfin directly competes. Catfish and other carps are the Highfin carpsuckers toughest competitors. It is possible for some of these species to survive in the same areas, but the Highfin carpsucker does best without much competition.
According to Ronald L. Woodwards and Thomas Wissinga, the abundance of Highfin carpsuckers may have a direct impact on traditional game species. This is due to the fact that these types of feeders - bottom feeders - are responsible for the “cleaning” of their habitat. Fisheries depend on them to keep the environment in check so it can support more marketable game species.

Life History

Highfin carpsuckers breed when temperatures are around 17° C. In Tennessee, these temperatures usually occur mid-May, though Highfins have been known to mate anywhere from April to June. They only breed once a year, not again in the fall like some species. Generally, the average clutch size of the Highfin carpsucker produces around 20 to 30 young. After spawning, the new organisms will live for around 11 years in the wild. However, if this species is grown in captivity, it may only live for 4 years. The maximum length ever recorded of a Highfin carpsucker is 50 cm (almost 20 inches) but the common length of these fish is 26.5 cm (about 10 inches).

Current Management of the Highfin Carpsucker

Recently the Highfin carpsucker was found in the Apalachicola River in Florida. A Highfin specimen was captured there in 2007, and marks the first time this species has been documented in this area. Previously, the Highfin carpsucker had never been documented east of the Choctawhatchee River that runs through Florida and Alabama. The researchers who discovered this population do not believe that this is a recent colonization, but instead a declining population. They believe the causes of this declination are due to many factors concerning the Apalachicola River.
In other areas where Highfin Carpsuckers are more commonly found factors such as pollution, habitat degradation, fragmentation, and siltation have caused the Highfin to experience major population losses. It is of significance that all of these factors are present in the Apalachicola River. Although further studies are needed to better determine the exact population status of the Highfin carpsucker in the Apalachicola River, there is a direct correlation between the status of this river and the low numbers of this fish species. The research conducted will show that with certain management practices in place the Highfin carpsucker could thrive in a section of the United States where it was previously thought not to exist. Since it has been determined that this Highfin colony is not new to the area, it is understood that this particular habitat can handle a larger population of Highfin carpsuckers.

Recommended Management Strategies for the Highfin Carpsucker

Areas where the Highfin carpsucker population is declining can be linked to certain factors present in their habitat. This particular species is not tolerant of many changes and needs a specific habitat not only to survive, but to flourish.
In areas that may need attention, an electroshock capture method should be used to determine the current status of Highfin carpsuckers and other related or competitive species in that area. To get an accurate count of the Highfin carpsucker the testing should be done in moderately shallow water, as this particular species thrives on a rocky gravel substrate where it can easily feed and spawn. In these certain areas it should be noted whether or not Highfins were caught. If so, the sex, age, and weight of each fish should be carefully documented. In areas where it would be logical for the Highfin carpsucker to be found but is not, data should be collected regarding the other species and conditions of these areas.
Using this practice will not only determine where Highfin populations exist, but will also help identify reasons why Highfin populations are not found in seemingly favorable habitats. In the areas where Highfin communities are not found, the conditions of the substrate should be carefully observed, as the Highfin carpsucker is a bottom feeder and relies heavily on this part of the habitat to support feeding and spawning. If this area becomes heavily silted, it will drive out the Highfin.
Humans have the most damaging influence on this species, since pollutants and erosion can have a large impact on the survival of the Highfin carpsucker. In areas where construction, dams, or other human activity is present, the impacts on the Highfins habitat should be carefully monitored.