Adriatic sturgeon. Credit: NOAA Fisheries.
Adriatic sturgeon. Credit: NOAA Fisheries.
About the Species
The Adriatic sturgeon is a large, long-lived anadromous species that spawns in freshwater after a period of growth in marine habitat. It is found in the Adriatic sea and the Po River and its inflow rivers in Italy. The Adriatic sturgeon is listed as endangered throughout its range under the Endangered Species Act.
Population Status
Adriatic sturgeon used to be widespread in the Adriatic Sea and may have occurred off the Iberian Peninsula. The only remaining spawning sites are at the confluences of the Po River and its tributaries in Italy, but the last known natural spawning occurred in the early 1980s. Population size is thought to have declined by at least 80 percent over the past three generations.
Protected Status
ESA Endangered - Foreign
CITES Appendix II
Appearance
The Adriatic sturgeon has an olivaceous brown back with lighter flanks and a white belly. Like all sturgeon, the species has a cartilaginous skeleton, heterocercal caudal fins (upper lobe larger than lower), single spiracle respiratory openings, a bottom-oriented mouth with four barbels (sensory “whiskers”), a flat snout, a strong rounded body, and unique ganoid scales.
Behavior and Diet
The species spawns in freshwater after a period of growth in marine habitat, typically at the mouth of rivers.
Where They Live
Adriatic sturgeon used to be widespread in the Adriatic Sea and may have occurred off the Iberian Peninsula. The only remaining spawning sites are at the confluences of the Po River and its tributaries in Italy, but the last known natural spawning occurred in the early 1980s. Population size is thought to have declined by at least 80 percent over the past three generations. Currently, the species has extremely low abundance in the wild, and recovery is dependent on a captive stock that only contains 13 remaining individuals of wild origin.
Lifespan & Reproduction
Male and female Adriatic sturgeon mature at 6 to 7 and 8 to 12 years of age, respectively, and the species has a lifespan of approximately 40 tp 50 years. Adults spawn every other year or more rarely.
Threats
The construction of the Isola Serafini hydroelectric power plant and dam in the early 1960s interrupted the migration of Adriatic sturgeon between freshwater and marine habitats. As a result, wild populations experienced drastic population declines. The dam continues to modify the habitat of the Adriatic sturgeon to such an extent that there is no confirmed record that the species has naturally reproduced in Italy since the 1980s.
Scientific Classification
| Animalia |
Chordata |
Actinopterygii |
Acipenseriformes |
Acipenseridae |
Acipenser |
naccarii |
