American Shad Restoration Project Seeing
Success
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June 14, 2006
Richmond, Virginia — The Virginia Department of Game and
Inland Fisheries (VDGIF) recently concluded the American shad brood
fish and egg collection operations for the 2006 spring season. Brood
fish and egg collection are key elements to Virginia's American Shad
Restoration Project. Egg taking crews on the Pamunkey and Potomac
rivers did an outstanding job this year, collecting a total of more
than 27 million fertilized American shad eggs. VDGIF also extends a
special thank you to the Interstate Commission On The Potomac River
Basin, the Potomac River Fisheries Commission, the U.S. Fish and
Wildlife Service, and Virginia Marine Resources Commission for their
assistance on this project.
All young shad, or fry, have been released from the King and Queen
Fish Cultural Station and the Harrison Lake National Fish Hatchery.
Both facilities had an outstanding production year, having an
overall survival rate of 58.6% of the received eggs hatched and
grown into fry stocked. As a result, all stocking goals for
Virginia's rivers were either met or exceeded in 2006.
In the James River system, the mainstem of the river above Bosher's
Dam received 5,067,543 shad fry. The Appomattox received 1,156,457
fry, and the Slate and Rivanna rivers both received over 400,000
fish. For the first time since stocking operations began on the
Rappahannock River in 2003, stocking goals were exceeded in that
system, with the mainstem receiving 4,914,507 fish, and the Hazel
being stocked with 1,350,281 fry.
Replacement stockings, for brood fish losses, accounted for the
release of 2,564,031 American shad into the Pamunkey (1,405,957) and
Potomac (1,158,074) rivers. The total number of shad larva released
in 2006 was 15,854,860 - bringing the total number of American shad
fry produced and stocked for this program to 134,264,560 since 1992
(A summary of these stockings is attached).
Background on the American Shad Restoration Project
American shad, the largest of the anadromous herring (or "clupeids")
in Virginia, once migrated westward in the James River to Covington
and beyond. The magnitude and sheer number of fish involved in these
great migrations astonished early Europeans. By the 18th century,
American shad and river herring had become one of the leading
commodities in the colonial economy, but that's also when problems
began to arise for these fish. The increased construction of dams
effectively blocked the westward migration of anadromous fish and
prevented them from reaching upland spawning and nursery waters.
Faced with the impact of urbanization and industrialization,
populations of American shad steadily declined over time. By 1994, a
moratorium on the inland harvest of shad brought an end to the rich
and deep traditions that both the commercial watermen and
recreational anglers had enjoyed for centuries.
In an effort to reintroduce and to enhance these fish in the James
River (while planning was on-going for fish passage structures to
breech the Richmond dams), the Virginia Department of Game and
Inland Fisheries began a restoration program in 1992 which continues
today. The American Shad Restoration Project uses a hatchery
stocking program to reintroduce "tagged" shad in the upper James
River system. A restoration effort was also started on the
Rappahannock River in 2003.
Successful Brood Stock and Egg Collection Lead to Successful
Stocking
Monitoring of adult American shad returning to spawn in the James
River has shown that the stockings have been extremely successful.
The population of American shad returning to the James has increased
dramatically, a large majority of the returning adults are from fry
stockings, and we are now seeing adult fish that are the offspring
of hatchery fish that returned and successfully spawned in the
river. These are positive signs that restoration efforts for
American shad on the James River are working.
As water temperatures rise into the low to mid 50s, shad actively
begin to spawn. Lengthening days and warming water temperatures find
biologists and commercial fishermen hard at work collecting brood
stock shad for egg-taking operations. Shad spawn primarily from late
evening until midnight, requiring most of the work to be done at
night.
Most male shad collected each evening are ready to spawn, but not
all females. Those that are not, are released back into the river.
Females in spawning condition and releasing eggs freely, a state
called "flowing," are quickly removed from the nets by the watermen
and placed on boats with live wells. The brood stock are then taken
to shore where the egg-taking process is done. Flowing fish are
manually spawned into bowls by massaging the fish's belly. Water is
then added to the bowls, which activates the sperm and fertilizes
the eggs. Egg fertilization rates can be improved from 5-35% in the
wild to as much as 95% through this manual spawning effort.
Once fertilized, the eggs are placed in water-filled tubs and left
undisturbed for a one-hour period. During that time, the eggs will
absorb water and swell to twice their original size-a process known
as becoming "water hardened." During this time, biologists are also
collecting information about the adult fish to find out more about
the age and growth of American shad spawning in Virginia.
Once water-hardened, the eggs are then placed in oxygen-filled bags
and taken to the hatchery. There, the eggs are counted before being
placed into hatching jars to incubate until hatched. The young shad,
or fry, hatch in 6 to 8 days, depending on water temperatures. The
jars are then placed into 200-gallon circular tanks where the fry
will remain for the next 21 days.
During their stay at the hatchery, the fry are fed a combination of
brine shrimp and salmon starter feed and marked with a permanent
tag. Tagging hatchery-raised fish is necessary to distinguish them
from wild fish, allowing biologists to evaluate the success of their
restoration efforts. After 21 days, the fry are loaded back into
trucks and are stocked into the rivers.
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