16155 South Hwy 377
Fort Worth, TX 76126
ESA Status Update from NOAA Fisheries:
Five distinct population segments of Atlantic sturgeon have been listed under the Endangered Species Act. The Chesapeake Bay, New York Bight, Carolina, and South Atlantic populations of Atlantic sturgeon will be listed as endangered, while the Gulf of Maine population will be listed as threatened.
Historically, Atlantic sturgeon ranged from Labrador, Canada to Florida, U.S., and inhabited most major river systems along the Atlantic coast. From the late 1800s to early 1900s, their populations declined progressively, primarily as a result of unregulated commercial fishing. A staggering seven million pounds of Atlantic sturgeon had been harvested by commercial fishermen as per commercial landing records of 1890. By 1920, the numbers dropped dramatically to only 22,000 pounds. Heavy fishing pressure, late reproductive maturity, and the prolonged spawning periodicity of Atlantic sturgeon proved to be a fatal combination for successful recovery of the species to sustainable populations. Regulated fishing, and restocking programs were inevitable. Other significant impacts which led to the Atlantic sturgeon's critical status and eventual extirpation in parts of their historic range include the construction of dams which blocked spawning migration, loss of habitat as a result of human encroachment, and water pollution. Today, all that remains of the once abundant Atlantic sturgeon are remnant populations in some of the larger rivers along the Atlantic coast.
Mike Hendrix, Director of the Northeast Fisheries Center in Lamar Pennsyvania for the USF&WS said the following about their restoration and restocking program:
Our role in the restoration of Atlantic sturgeon is to develop culture techniques of this species so that that information can be rotated out to other field stations to produce these fish in captivity if it’s necessary to do a stocking program. A stocking program would be the last alternative that we use to restore a species. We want to use regulation and habitat improvement to try restore species before we start enhancment stocking. But in some cases populations are so low and so depleted that we do have to use a stocking program to build them back."
See the Jerre Mohler-Boyd Kynard-Brian Dickson Interviews at the Sturgeon Gallery for important information about using hatchery raised stocks for restocking programs.
Gulf sturgeon and Atlantic sturgeon are of the same genus, and look very similar in appearance, however, there are a few distinguishable differences; the most obvious being geographical. It is believed the emergence of the Florida peninsula well over a million years ago separated the two species. The separation was then maintained by the thermal barrier of the Gulf stream around south Florida.
Gulf sturgeon are further distinguished from their Atlantic counterparts by their squarish dorsal scutes, longer head and pectoral fins, and notably longer spleen. DNA studies have defined genetic differences as well, and further identified five river-specific population groups of Gulf sturgeon which are maintained by strong homing instincts. DNA information is utilized in management efforts as an aid to preserve genetic integrity.
Sturgeons have certain characteristics which vary slightly from species to species. They have a heterocercal tail much like that of sharks, and a skeleton
composed almost entirely of cartilage rather than bone. They have a torpedo shaped body which helps them glide effortlessly through the water….four large barbels that dangle just in front of the mouth, and serve as sensory organs…..and a rubbery, siphon-like mouth that acts like a vacuum for these opportunistic bottom feeders.
Sturgeons don't have scales, rather their bodies are armored with several lengthwise rows of bony plates called scutes. Scutes are thought to have been used by ancient peoples, and Native Americans for tools and ornamentation. The scutes of young Gulf sturgeon have sharp points which helps discourage predation. As the fish matures, the points wear down to a more rounded surface that is hard and durable. Adult sturgeons have no known predators, other than man.
Gulf sturgeon are one of the largest species of fish that inhabit both fresh and salt water. They can grow over 9 feet in length, and weigh more than 300 lbs., although fish that size are rare. Young sturgeons grow rapidly during the first few years of life, but the growth rate slows as they mature. They are long lived, and typically reach ages well over 40 years.
Gulf sturgeon are anadromous, which means they migrate from saltwater into freshwater rivers to spawn. Juveniles and adults participate in the yearly migration which begins in February or March. They remain in the rivers throughout the summer, and return to saltwater in the fall. The reason for this behavior remains a mystery.
For the classroom, "The Gulf Sturgeon" is available on DVD in our DVD Gallery. It can also be viewed online at the Earthwave Society Channel on YouTube.
16155 South Hwy 377
Fort Worth, TX 76126