FOLLOW US:

Stay connected with us
around the nation »


European Sturgeon (Acipenser sturio)

Status | Species Description | Habitat | Distribution | Population Trends | Threats | Conservation Efforts | Regulatory Overview | Taxonomy | Key Documents | More Info

Status

ESA Endangered - throughout its range
CITES Appendix I - throughout its range

Species Description

Weight:
up to 2,200 pounds (1,000 kg)
Length:
20 feet (6 m)
Appearance:
olive-black with a white belly; they have 5 major rows of "scutes"
Lifespan:
uncertain, but likely up to 50 years
Diet:
worms, crustaceans, mollusks
Behavior:
they migrate upriver in spring to spawn

European sturgeon are large, long-lived, estuarine-dependent, "anadromous" fish. They can grow to 16-20 feet (5-6 m) long and can weigh up to 2,200 pounds (1,000 kg). They are olive-black with white belly. They have five major rows of dermal scutes. They have an elongated body with a narrow-tipped snout. Their mouth is interrupted at the center of their lower lip.

European sturgeon are "benthic" feeders and typically forage on benthic invertebrates. Their reproductive phase begins at 10-18 years old, later than many other sturgeons, with males reproducing for the first time at 10-12 years and females at 13-18 years. Size at maturity varies from about 3-4 feet (0.9-1.3 m) in males and about 3-6 feet (0.9-1.8 m) in females.

Atlantic and European sturgeons are closely related. At one time, they were considered two sub-species: A. sturio oxyrinchus and A. sturio sturio, respectively. In 1963, they were separated into two species (A. oxyrinchus, A. sturio) based on morphological and meristic characters.

Habitat

They live in both marine and freshwater. They spawn in freshwater, and then mature from juvenile to adult in marine waters near the shore. Then, as adults, they return to freshwater to spawn. They can tolerate a wide range of salinities.

Juveniles make a slow descent downstream to the estuary and are present in the upper estuary of their birth rivers at one year of age. Juveniles enter the sea after 2-6 years, during which they alternate movement between the sea and spending the winter in the estuary. For the next 4-6 years, they enter the lower estuary at summer time and return to the sea in the fall. As adults, they are generally found close to shore in the sea and are never found in waters deeper than 650 feet (200 m).

Distribution

European sturgeon are restricted to:

Historically, European sturgeon were abundant in the North Sea, the English Channel, and most European coasts of the Atlantic Ocean, the Mediterranean Sea, and the Black Sea.

Population Trends

The current population size is roughly estimated at 20-750 adults. European sturgeon are thought to have declined by at least 90% over the past 75 years. No natural reproduction has been documented in the wild since 1994.

Large numbers have been stocked from hatchery programs in the past few years, but they have not yet reproduced:

Threats

Historically:

Current threats include:

Conservation Efforts

European sturgeon are listed in Appendix I of CITES, which regulates international trade.

They are listed in Appendix II of the Bern Convention on the Conservation of European Wildlife and Natural Habitats, which prohibits "take" and deliberate habitat destruction. All countries that have signed the convention must coordinate efforts to protect at-risk species and promote:

They are also listed in Appendix I of the Convention on Migratory Species.

Most nations in the species range protect the species through national law. Extensive stocking programs exist, especially in France and Germany.

Regulatory Overview

In 2012, WildEarth Guardians and Friends of Animals petitioned [pdf] us to list 15 foreign sturgeon species under the ESA. We proposed to list 5 species as endangered under the ESA. (The other 10 species were determined to be under the jurisdiction of the U.S. Fish and Wildlife Service, and USFWS is reviewing their status.)

Taxonomy

Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Acipenseriformes
Family: Acipenseridae
Genus: Acipenser
Species: sturio

Key Documents

(All documents are in PDF format.)
Title Federal Register Date
Final Endangered Listing of Five Sturgeon Species 79 FR 31222 06/02/2014

Proposed Endangered Listing of Five Species of Sturgeons under the ESA

78 FR 65249 10/31/2013
Status Review   10/2013
90-day Finding on a Petition To List Five Species of Sturgeon as Threatened or Endangered under the ESA 77 FR 51767 08/27/2012
Petition to List 15 Sturgeon Species as Threatened or Endangered n/a various

More Information

Updated: January 21, 2015