One of Central California’s most ancient fish,
the green sturgeon, will soon have a new recovery plan to steer it toward
NOAA Fisheries this week released a draft
recovery plan under the Endangered Species Act for public comment.
The plan itself is non-regulatory. Rather, it
identifies steps to guide state and federal actions that will promote recovery
of the green sturgeon’s depressed southern population.
The plan can be found at http://www.westcoast.fisheries.noaa.gov/protected_species/green_sturgeon/green_sturgeon_pg.html
NOAA Fisheries biologists divide the green
sturgeon into two distinct populations segments based on what is known about
the species. In 2006, the southern population – covering Central California –
was listed as threatened under the ESA. The northern population was more
abundant and listing was not warranted at the time.
As part of the ESA protection, NOAA Fisheries
has been working with the states of California, Oregon, and Washington, other
federal agencies, and non-governmental organizations to identify actions to aid
in the recovery of the southern population of green sturgeon.
The recovery plan – which is now open for
review and public comment – identifies a number of research, monitoring, and
outreach actions aimed at restoring fish passage and habitat, reducing sources
of mortality, and addressing known threats including climate change, predation,
and contaminants. Most recovery efforts focus on threats to freshwater and
estuarine spawning and rearing habitats; the areas that are considered the
greatest impediments to recovery.
“The recovery plan is a key step in promoting
public awareness of green sturgeon and encouraging participation in restoring
the southern population,” says Joe Heublein, a NOAA Fisheries biologist who
coordinates the multi-agency recovery effort.
Green sturgeon spend most of their lives in
nearshore ocean waters off the coast of California, Oregon, and Washington.
Like other sturgeon and salmon species, they are anadromous, meaning they
return every few years from the ocean to freshwater rivers to spawn (unlike
salmon, sturgeon don’t die after they spawn).
An estimated 1,300 adult green sturgeon remain
in Central California. This southern population has declined over the last
several decades due largely to both habitat loss and dams that have blocked
access to their traditional spawning areas. Most spawning adult sturgeon are
found in the Sacramento River. This singular concentration of spawning adults
puts the southern population at greater risk of being wiped out by a single
Further challenging recovery is the fact that
green sturgeon are slow to mature. They start reproducing around age 15. Older
individuals may live to be over 50 years old, reaching nearly seven feet and
weighing more than 350 pounds. Because they are long-lived and slow-growing,
scientists may not see evidence of rebounding abundance for years.