Sturgeons of the Caspian Sea and Ural River

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1 Photo and image credits: Front Cover: Top left, beluga sturgeon (Huso huso); Top Right: Russian sturgeon (Acipenser gueldenstaedtii); Bottom: stellate sturgeon (Acipenser stellatus); Todd Stailey, Tennessee Aquarium. Back Cover: FISH IS OUR TREASURE, Phaedra Doukakis, Ph. D. IOCS; Page 1: Shannon Crownover, The Nature Conservancy; Page 6, 9, 10, 11: Phaedra Doukakis, Ph. D., IOCS; Page 4, 5, 7 designed by Grace Lewis. Brochure content was developed by Alison Ormsby, Ph.D. and Phaedra Doukakis, Ph. D. with editorial review by Yael Wyner, Ph. D. Layout was designed by Grace Lewis. The brochure was developed under a generous grant from Agip KCO. Agip KCO 1, K. Smagulov Street Atyrau, Republic of Kazakhstan Designed and printed in Kazakhstan Tel.: international line: Tel: local lines: (+7) Fax: (+7) Sturgeons of the Caspian Sea and Ural River A Unique and Precious Resource

2 What are Sturgeon? With bony plates called scutes on their bodies and ancestors that date to the time of dinosaurs, sturgeons are unusual fish. Unlike other types of fish, sturgeons have scutes instead of scales. River, other rivers off the Caspian Sea are used by sturgeons for reproduction, including the Volga River in Russia and the Kura River in Azerbaijan. However, dams on the Volga and Kura have blocked sturgeons from being able to migrate upriver, and have changed the quality of the rivers so they are no longer able to support sturgeon reproduction. Reproduction: For sturgeon, the process of mixing female eggs and male sperm to create a fertilized egg that hatches into a baby sturgeon. Caviar is unfertilized sturgeon eggs. Migration: Movement from one area to another area for a purpose such as feeding or reproduction. For example, sturgeon migrate up the Ural River to reproduce. Stellate, beluga and Russian sturgeon. The scutes are the ridges along the back and side of the fish. There are 25 different kinds, or species, of sturgeons in the world. Sturgeons live throughout the Northern Hemisphere, including in the Black Sea, Sea of Azov, Lake Baikal, and the Mississippi River, USA. Six species of sturgeon can be found in the Caspian Sea. The beluga (scientific name Huso huso) is the largest and most valuable species. All six species use the Ural River, and five of the six species are captured for meat and caviar (sturgeon eggs). One species, the ship sturgeon (Acipenser nudiventris), is protected. The River-Sea Connection All sturgeons on earth depend upon freshwater for their survival. Sturgeons reproduce in freshwater. In addition to the Ural In addition to blocking migration, dams cause changes in river shape and qualities. Some of these changes affect the sturgeons ability to know where and when to reproduce. The cues or signals that sturgeons rely upon to tell them that the conditions are right for reproduction include river temperature, speed of the flow of the river, and river bottom characteristics. For species like beluga sturgeon, 90% of the natural spawning grounds have disappeared. The Ural River is now the only river off the Caspian Sea that does not have a dam that blocks the migration of beluga and other sturgeons. Therefore, the Ural River is very important, being one of the last great places for Caspian Sea sturgeons and the best hope for the future. 2 3

3 N = town = dam km Orenburg These are the main steps in the life cycle of a sturgeon in the Ural River. 1. Adult sturgeon first must find the right place in the Ural River for reproduction. Baby sturgeon will begin their lives here as eggs. 2. The eggs settle to the bottom where they hatch into very small sturgeon after a few days. Ural River Volga River RUSSIA Atyrau KAZAKHSTAN 1 Caspian Sea UZBEKISTAN GEORGIA 4 2 ARMENIA Kura River AZERBAIJAN TURKMENISTAN 3 IRAN 3. Within a few months, the tiny sturgeon develop into fingerlings, drifting and swimming downstream towards the river mouth. Main rivers of the Caspian Sea for beluga sturgeon The Sturgeon Life Cycle There are several stages in the life of a typical sturgeon. Taken as a whole, this process is called the sturgeon life cycle. 4. The young sturgeon gather in the mouth or delta of the Ural River to eat and grow larger. As they develop into adults, they move offshore into coastal waters. After many years in the sea, the adults migrate far up the Ural River to have their young. 4 5

4 Depending on the kind of sturgeon, it takes 7 to as long as 20 years for the animals to become old enough to reproduce. During this time, the animals live in the Caspian Sea in the north in the warmer months and in the south in colder winter months. Depending on the species of Sturgeon fingerlings sturgeon, the adult fish return to the rivers every 2 to 5 years to reproduce. The beluga sturgeon reproduces only in the upper Ural River at sites 500 to 800 kilometers from the river mouth. A Unique Natural Wonder The group of fishes including the sturgeons has a long history. These fishes first appeared over 150 million years ago in the Jurassic geologic period during the time of the dinosaurs. The Uses of Sturgeon In addition to caviar and meat, many parts of sturgeon have uses. Glue, also known as isinglass, is made from sturgeon. Sturgeon skin can be dried for leather products such as belts and handbags. Parts of sturgeon are thought to have medical properties in treating arthritis and cancer. Sturgeons are unusual fish for many reasons, not just because they are ancient fish that need both river and sea environments to grow and reproduce. Compared with other fish, sturgeons can live a long time and grow to an impressive size. The beluga is considered one of the largest freshwater fish on earth, with the biggest individual fish recorded at over 6 meters in length, nearly 1,300 kg and 118 years old! Beluga need to be at least 12 years old before they are able to reproduce, and they 6 m do not have young every year. Sturgeons are valued around the world for their meat and eggs. Caviar is the unfertilized 1.8 m eggs of sturgeon. Individual female fish must be killed for their caviar. When females are taken for their caviar or males are removed as they enter the Ural River, these fish have not yet had a chance to reproduce. If many sturgeons are harvested over a short time, eventually there will be fewer older sturgeon and fewer young. Sturgeon fishing has a long history. Some historians trace the origin of caviar to Batu Khan, the grandson of 6 7

5 Ghengis Kahn, in 1240 AD. Through history, fishing for sturgeon illegal fishing, and the occurred in the Caspian and Black Sea regions, western Europe trade in caviar. In some and North America. In the late 1800s to early 1900s, the east coast areas of the world, of North America was an important center of sturgeon fishing and sturgeon fishing is no caviar production. In this case, too much fishing caused there longer allowed. Illegal to be few sturgeon left to support fishermen. Fishing eventually fishing is still a problem stopped and the species were protected. The focus then shifted to in many areas. Better the Caspian Sea, which had the highest concentration of sturgeon control of fishing and ever recorded for any body of water. international trade can ensure that sturgeons The sturgeon plays survive into the future. a central role in Kazkakhstani society and In the Caspian Sea and culture, with meat and Ural River, scientists caviar served at special and fishermen have events and celebrations. noticed that there are In addition, caviar can be not as many sturgeon an important part of the as there once were. diet, thought to be very There are currently efforts to control fishing and protect important nutritious especially for sturgeon habitat. Sturgeons are being raised in special places young children. called hatcheries to be released into the Ural River and Caspian Scientists and guards on the Ural River with beluga sturgeon Sea. While hatcheries can help, they cannot be the only place Saving Sturgeons where sturgeons reproduce. Reproduction in the natural habitat of In many parts of the world, the Ural River is still very important. there are so few sturgeon left that they may be close to extinction. This Visitors at the Fishermen s Day Festival in Atyrau celebrating sturgeon 8 is because of pollution, river dams, legal and Habitat: The place that contains the food, water, shelter and space necessary for an animal to survive. 9

6 Remaining Mysteries Where do sturgeons go There are still many to reproduce within the unanswered questions about Ural River? By tracking the life of sturgeons. As the movements of fish in described below, a team of the river, we can find and Kazakhstani and American protect the habitats used researchers has been studying for reproduction. key mysteries of Ural River sturgeons. One important Do individual sturgeon method that is used is marking return to the river where or tagging a fish and tracking they were born to its movements. reproduce? It is not known whether sturgeons born Beluga sturgeon with tag Where do sturgeons go once in the Ural River return to they leave the Ural River? It reproduce or if they travel can be very hard to understand the habits of aquatic animals Researcher puts tag in sturgeon fingerling in the hatchery to other rivers such as the Volga or Kura. because we cannot see what is happening underneath the How many of the adult fish in the wild were born in hatcheries? This water surface. Scientists question is being studied using very small tags that are inserted into believe that sturgeons live in the young sturgeon and stay in the animal for its life. the north Caspian Sea in the warm months and in the south Caspian Sea in the winter months. Special tags are It is important that we all help preserve sturgeon, being used to further study the Kazakhstan s unique and precious resource. Please movements of adult sturgeons do your part in learning what role you can play in in the Caspian Sea. saving sturgeons. The Ural River 10 11