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Home , Acipenser, Beluga (sturgeon), Huso, Or (river), Russian sturgeon, Sturgeon

Photo and image credits: Front Cover: Top left, ( huso); Top Right: ( gueldenstaedtii); Bottom: stellate sturgeon (Acipenser stellatus); Todd Stailey, Tennessee Aquarium. Back Cover: “ 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 Tel.: international line: 1, K. Smagulov Street +39 02 9138 3300 , 06002 Tel: local lines: Republic of (+7) 7122 92 3300 Fax: (+7) 7122 92 3310 Designed and printed in Kazakhstan www.agipkco.com

Sturgeons of the and River www.oceanconservationscience.org A Unique and Precious Resource What are Sturgeon? River, other rivers off the Caspian Sea are used by for With bony plates called scutes on their bodies and ancestors that reproduction, including the River in and the date to the time of dinosaurs, sturgeons are unusual fish. Unlike River in . However, on the Volga and Kura have other types of fish, sturgeons have scutes instead of scales. 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. is unfertilized sturgeon eggs.

Migration: Movement from one area to another area for a purpose such as feeding 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. In addition to blocking migration, dams cause changes in river There are 25 different kinds, or , of sturgeons in the world. shape and qualities. Some of these changes affect the sturgeons’ Sturgeons live throughout the Northern Hemisphere, including in ability to know where and when to reproduce. The cues or signals the , , , and the River, that sturgeons rely upon to tell them that the conditions are right USA. Six species of sturgeon can be found in the Caspian Sea. for reproduction include river temperature, speed of the flow of the The beluga (scientific name Huso huso) is the largest and most river, and river bottom characteristics. valuable species. All six species use the Ural River, and five of the six species are captured for meat and caviar (sturgeon eggs). One For species like beluga sturgeon, 90% of the natural spawning species, the ship sturgeon (Acipenser nudiventris), is protected. grounds have disappeared. The Ural River is now the only river off the Caspian Sea that does not have a that blocks the The River-Sea Connection migration of beluga and other sturgeons. Therefore, the Ural River All sturgeons on earth depend upon freshwater for their survival. is very important, being one of the last great places for Caspian Sea Sturgeons reproduce in freshwater. In addition to the Ural sturgeons and the best hope for the future.

2 3 These are the main steps in the life cycle of a sturgeon in the = town Ural River. N = dam 0 200 km 1. Adult sturgeon first must find the right place in the Ural River for reproduction. Baby sturgeon will begin their lives here as eggs.

Ural River 2. The eggs settle to the bottom where they hatch into very small

V sturgeon after a few days. olga River Atyrau KAZAKHSTAN RUSSIA

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UZBEKISTAN Caspian Sea 4 2

Kura River ARMENIA AZERBAIJAN 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 4. The young sturgeon gather in the mouth or delta of the Ural The Sturgeon Life Cycle River to eat and grow larger. As they develop into adults, they move There are several stages in the life of a typical sturgeon. Taken as a offshore into coastal waters. After many in the sea, the adults whole, this process is called the sturgeon life cycle. migrate far up the Ural River to have their young.

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

6 7 Ghengis Kahn, in 1240 AD. Through history, fishing for sturgeon illegal fishing, and the occurred in the Caspian and Black Sea regions, western trade in caviar. In some and . In the late 1800s to early 1900s, the east 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 Scientists and guards on the Ural River with In addition, caviar can be not as many sturgeon beluga 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 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 . This Habitat: The place that contains the food, water, shelter is because of pollution, and space necessary for an to survive. Visitors at the Fishermen’s Day Festival in river dams, legal and Atyrau celebrating sturgeon

8 9 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 Where do sturgeons go once in the Ural River return to they leave the Ural River? It reproduce or if they travel Beluga sturgeon with tag can be very hard to understand to other rivers such as the Researcher puts tag in sturgeon fingerling the habits of aquatic animals in the hatchery 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 It is important that we all help preserve sturgeon, months. Special tags are 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

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