Lake Sturgeon Reintroduction into the Upper Coosa River …



Chapter 3—White-tailed Deer, Lake Sturgeon, American Alligator

This chapter highlights species that are points of focus during the fall months. The following accounts and information on the white-tailed deer, lake sturgeon, and American alligator will explain why these species are important wildlife resources and what is being done to responsibly manage these species. You can go directly to any of these sections by clicking on their name: White-Tailed Deer; Lake Sturgeon; American Alligator.

LAKE STURGEON

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COMMON NAME: Lake sturgeon (Rock sturgeon, Dogface sturgeon, Rubbernose)

SCIENTIFIC NAME: Acipenser fulvescens (Acipenser – sturgeon; fulvescens – dull yellow color)

IDENTIFICATION: Lake sturgeons have several characteristics that identify them from other fish. Sturgeons have sharp bony plates (scutes) along their back and sides. As sturgeons age, these scutes get smoother and become barely visible. Sturgeons have a shark-like tail (heterocercal tail) that is connected to a backbone made of cartilage. The sucker-like mouth is located on the underside of the head and can be extended to feed. Four “whiskers” (barbels) located just in front of the mouths are sensory organs and help in the location of food. Young lake sturgeons have very pointed snouts that become blunter and shorter with age. Older lake sturgeons are slate-blue to olive brown in color with yellow-white bellies while young lake sturgeon are light in color and have dark blotches on sides and snouts.

RANGE: The ancestors of this ancient species made their appearance about 100 million years ago. Based on collection records and interviews with anglers, the historical range of the lake sturgeon in Georgia included the Etowah, Oostanaula, Coosawattee, and Coosa rivers. In Alabama, the lake sturgeon was found downstream in the Coosa River to near Childersburg. The lake sturgeon disappeared (was extirpated) from the Coosa River basin in the late 1960’s. In North America, the lake sturgeon ranged from Canada, throughout the Midwest, Great Lakes, and Mississippi Valley to the Coosa Basin but its current population numbers less than 1% of the its pre-1900 size. The lake sturgeon is considered rare and good reproducing populations are limited to the upper Midwest and the Great Lakes region. Pollution, over fishing, and habitat loss contributed to the decline of the lake sturgeon

LIFE HISTORY: Lake sturgeon migrate to their spawning grounds between April and June preferring to spawn in shallow, rocky areas along river banks. Spawning occurs between 50oF - 58 oF depending on water flow. Females do not reach sexually maturity until 16 to 23 years old and then only spawn once every four to six years. Males mature at about 14 to 16 years and spawn every one to two years. Spawning occurs when the female joins a group of about six to eight males. The sturgeon will swim against the current, thrashing their tails, while releasing milt (sperm) and eggs. A female can release anywhere from 50,000 to 700,000 eggs. The eggs cling to rocks and other solid material until they hatch in five to eight days. Lake sturgeons are bottom feeders and use their mouths to suck up food such as insect larvae, worms, leeches, snails, and small clams. At first, lake sturgeon will grow rapidly (up to three feet in five years) but growth slows, as the fish gets older. Lake sturgeon can reach over 200 years old and six feet in length. The largest lake sturgeon on record was almost eight feet long and weighed over 300 pounds.

REINTRODUCTION EFFORTS IN GEORGIA: After about a 35-year absence, lake sturgeon returned to the Coosa River system in 2002 to begin a 20-year restoration effort. The yearly cycle begins with eggs provided by the Wisconsin Department of Natural Resources that were hatched and reared to fingerlings at the Georgia Wildlife Resource Division’s Summerville Hatchery. In October 2002, elementary school children from Armuchee and the City of Calhoun helped release 1,127 five to seven inch lake sturgeon into the Oostanaula River. The 2002 releases appeared to be successfully as anglers in the summer of 2003 reported seeing lake sturgeon 12 to 15 inches long. In 2003, release points were expanded to include the Etowah and Coosawattee Rivers. In 2004, researchers from the University of Georgia, Warnell School of Forest Resources began population assessments and radio telemetry studies to quantify introduction success, determine seasonal movements, and identify habitat critical to the lake sturgeon.

MANAGEMENT: The goals of the reintroduction effort are to establish a self-reproducing population of lake sturgeon that can support a sport fishery; and to support the national effort of preserving the species. Under current Georgia regulations, lake sturgeon cannot be harvested and must be released immediately. If a lake sturgeon is accidentally caught, it should be released while still in the water. If hooked deep, cut the line close to the hook. If you observe a sturgeon, find a dead specimen, or accidentally catch one, please contact the Wildlife Resources Division, Fisheries Management Section. The information you provide will be invaluable in our restoration efforts.

Credits:

Becker, George. 1983. Fishes of Wisconsin. University of Wisconsin Press

Heaton-Vecsei, Sarah. Sturgeon line drawing. University of Georgia, Warnell School of Forest Resources

Mecozzi, Maureen. 1988. Lake sturgeon. WI Dept of Natural Resources PUBL-FM-704-88

Questions and Answers

Q. What are lake sturgeon?

A. Sturgeons (about 27 species world-wide) are a very unique, awe-inspiring group of fish that look like they belong more with dinosaurs than with our current day freshwater fish. In fact, they did coexist with dinosaurs and have changed little since that time. They are a cartilaginous (nearly boneless) fish with a shark-like tail, sucker-like mouth, sensitive barbels under its snout and rows of bony scutes (plates) on the side and top of its body. The lake sturgeon is a species that is found primarily in the Great Lakes and Mississippi River drainage area but was also found in the Coosa River basin in northwestern Georgia and northeastern Alabama. Unfortunately, lake sturgeon disappeared from the Coosa River system in the 1960s.

Q. How big and how old do lake sturgeon get?

A. One lake sturgeon on record lived to be 154 years of age and another tipped the scales at 310 pounds. Both these records were from northern states in the early 20th century and few, if any, such fish exist today. Unfortunately, little was recorded about the Coosa River population of lake sturgeon but they probably did not live as long or get as large as northern fish due to the warmer waters. Biologists have found a few old pictures of Coosa drainage fish in which the fish appear to weigh up to about 40 pounds.

Q. What do lake sturgeon eat?

A. Sturgeons are primarily bottom feeders that find their food by smell and touch. Food consumption studies indicate lake sturgeon feed on almost anything they can find, which includes invertebrates, insect larvae, crayfish, worms and mollusks. While these studies found that sturgeon eat some fish and fish eggs, they were not a large component of the lake sturgeon diet. Most food consumption studies found that food items were typically eaten in proportion to the item’s abundance in the environment. However, several researchers reported a preference for soft-bodied invertebrates such as mayflies.

Q. Why does the Georgia Department of Natural Resources want to stock lake sturgeon?

A. One reason for stocking lake sturgeon is to reestablish a sport fish. Fishermen reported good harvests of lake sturgeon into the early 1960’s but the fish suddenly disappeared. Considering the longevity of lake sturgeon and the heavy harvests reported by some fishermen, over-harvest was likely a factor in the disappearance of the Coosa River fish. Biologists believe the species can once again be part of the river ecosystem and provide some harvest if monitored and managed carefully. Lake sturgeon are prized by sportsmen primarily for their meat and eggs.

Another reason to restore the species is that most people are interested in the preservation of rare species. In one recent survey, 72% of Georgians favored more money and time be devoted to the management of imperiled species. Lake sturgeon are certainly one of the more interesting of these species due to their size, unique appearance and longevity. By reintroducing lake sturgeon, Georgians are contributing to the preservation of a fascinating species.

Q. Why are lake sturgeon populations in such bad shape?

A. When European settlers first started fishing the Great Lakes the lake sturgeon had little value and were considered a nuisance because they would tangle fishermen’s nets. They were wastefully slaughtered in much the same way as the American buffalo. So invaluable were the fish that they were tossed on the bank to rot, fed to hogs and even dried and burned as firewood. About 1860 their value increased dramatically as the demand for their flesh, eggs, and other products increased. Over-harvest quickly occurred and the population dropped to a fraction of its original abundance. In Lake Erie, for example, harvest was over 5 million pounds in 1895 but by 1905 the total harvest was only 100,000 pounds. Despite surviving millions of years, which included events resulting in the extinction of dinosaurs and the ice age, lake sturgeon populations were destroyed by man’s activities in just a few decades.

Recovery efforts are hampered by the lake sturgeon’s low reproductive capabilities. Females from the Great Lakes area do not reproduce until they are 14-25 years of age and then only reproduce every four to nine years. Although lake sturgeon are expected to mature faster in the warmer waters of the Coosa River system, their reproductive capabilities will still be far below other species.

While over-harvest is likely the main cause of the decline, dams that block spawning movements and water pollution have also been blamed. Today, like most sturgeons in the world, lake sturgeon populations are weak and the species continued existence is a concern for fishery managers. Current population numbers are estimated to be less than 1% of their original abundance. Despite the drastic decline in sturgeon numbers, the demand for sturgeon eggs and flesh remains high today. Because of its value, poaching is a concern that further threatens the species.

Q. Are the original Coosa system lake sturgeon really gone?

A. GADNR biologists reviewed 40 years of general fish sampling data from the area, consulted with citizens and staff of other agencies, and sampled specifically for sturgeon using a variety of methods. Although there is one claim that two fish were found in an area pond in 1980 (which has since been drained), biologists found no substantiated evidence that the fish remained in the Coosa system after the middle 1960s.

Q. How will lake sturgeon affect other species, particularly crappie?

A Although sturgeon will eat fish if they can, their blind, ambling feeding behavior limits their ability to prey on fish, especially mobile species such as crappie. Sturgeon are also known to eat fish eggs (as do most fish) which potentially could reduce crappie reproduction. On the other hand, sturgeon also eat the eggs of crappie competitors and predators, thus reducing competition and reducing species that prey on crappie. So, will sturgeon help or hurt other fish populations? The answer is neither. Sturgeon numbers will be too low to significantly impact other fish populations either positively or negatively. Nowhere is overpopulation of lake sturgeon a problem. In fact, most states in its range do not have enough lake sturgeon to keep them off their rare and endangered species lists. The lake sturgeon’s low reproduction rate makes the chance of them overpopulating virtually impossible. Even if they did reproduce to greater numbers than desired, it would be easy to reduce the population through harvest regulations since demand for the species is high. Remember also that lake sturgeon are a native species, not an exotic species, which has never been tested in the system before. Lake Weiss itself likely harbored lake sturgeon after it was built. The dam was completed in 1961, which is a few years before the lake sturgeon disappeared from the Coosa River system. Regarding rare species, keep in mind that sturgeon are opportunistic feeders which generally feed on the foods which are most abundant. Thus, if a species is rare, sturgeon will rarely eat it.

Q. Where will you stock the sturgeon?

A. Sturgeon will be stocked at numerous sites in the Etowah and Oostanaula Rivers because these rivers were the last reported locations to contain lake sturgeon. There are no current plans to stock above Allatoona or Carters Reservoirs.

Q. How many sturgeon will GADNR stock and how big will they be?

A. An initial stocking of 1000 six-inch sturgeon is planned for December 2002. Future stocking will probably be earlier in the year when the fish are four to five inches in size. Biologists will also stock a smaller number of 12-inch fish to see if their survival is significantly better that that of the smaller fish. Numerous studies are planned to monitor the success of the reintroduction program. Results of this monitoring will be used to fine tune future stockings to improve success. Biologists estimate it will take 15-20 years of stocking to reestablish the lake sturgeon to the Coosa River system.

Q. When will we be able to harvest lake sturgeon again?

A. Before harvest can begin, biologists must be sure the lake sturgeon are surviving to reproductive age and reproducing naturally. Biologists will then need to determine the level of recruitment to adult size and carefully determine how much harvest can be allowed. Given the slow maturity of lake sturgeon and their longevity, it will likely take several decades before harvest will be permitted. Until that time, some sturgeon will be caught and admired but should be returned immediately to the water.

Q. How can I help?

A. Any information regarding catches of sturgeon will be extremely valuable to biologists during the first few years of this reintroduction project. If you catch a sturgeon measure it, record external tag numbers, if present, and return the fish immediately to the water. Report this information along with the date of catch, location of the catch and your name and phone number to the address below.

Georgia Department of Natural Resources (GDNR)

PO Box 519 – Calhoun, GA 30703

(706) 624-1161

Learning Activities

1. A number of Project Wild/Aquatic Wild activities provide supplemental material emphasizing fish or concepts related to fish as a natural resource and their relationships to people. These activities can enhance and reinforce the written background material for the Lake Sturgeon:

|Aquatic Wild Activity Name |Page |Key Concept(s) |

|Fishy Who’s Who |8 |Identification |

|Hooks and Ladders |43 |Fish Migration & Limiting Factors |

|Fashion a Fish |56 |Adaptations |

|Watered-Down History |91 |Society & Development |

|What’s in the Water |140 |Human Impacts |

|Something’s Fishy Here! |145 |Human Impacts |

2. The Aquatic Project WILD manual provides an excellent overview of the aquatic ecosystem on pages 224-228.

3. Watching fish in an aquarium is a fun and interesting activity for children. The Aquatic Project WILD manual provides useful information about setting up and maintaining an aquarium on pages 229-232.

4. Fishing is also a fun way to learn about fish and fishing. The Fisheries Section sponsors Kids Fishing Events throughout the year at many different locations around the state. A list of Kids Fishing Events is posted on the Fisheries Section webpage at . At the site, click on the fish and then click on the “Take a Kid Fishing” icon. If you would like to sponsor an event, contact your local Fisheries Office for more information.

5. Two DNR Videos entitled First Time Fishing and Fishing Fun offer tips for beginning anglers to help them get hooked on fishing. Contact your local Fisheries Office to check out the videos.

Supplemental Material:

• Lake Sturgeon Information by Wisconsin Department of Natural Resources – Information detailing the biology and management of Lake Sturgeon in Wisconsin with great drawings useful in teaching.

• USFWS Lake Sturgeon Brochure – Color brochure highlighting history and management of Lake Sturgeon in the United States.

Internet Resource Links:

• kids - North Carolina Division of Marine Fisheries Has good information and resources that are targeted at students.

• - North Carolina Wildlife Division Has good information and resources that are targeted at students.

• directory/educational_resources/fishing-The Recreational Boating & Fishing Foundation provides a number of links to quality aquatic education resources.

• aged.ces.uga.edu-usful - useful information about the aquatic ecosystem is available in the Envirothon materials that are provided through the University of Georgia Cooperative Extension Service.

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• - Georgia Department of Natural Resources lake sturgeon information.

• -Great Lakes Indian Fish & Wildlife Commision-Sturgeon-King of Fish: Native American lore and poster.

• Lakes Lake Sturgeon

• - U.S. Fish & Wildlife Service website detailing Lake Sturgeon management

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