known about small juveniles that may be less able to Conservation
avoid impingement. Smith et al.^11 believe the low
abundance of Savannah River juveniles was caused The primary need of shortnose sturgeon conserva-
by dredging in the fresh/saltwater interface. A sim- tion is completion of a recovery plan for the species.
lar situation may exist in other rivers. This plan will guide the direction of futureconser-
Shortnose sturgeon are protected from directed vation efforts. Generally, conservation should in-
fisheries, but they are captured across their range as sure that existing populations survive and increase
bycatch, mainly in gill net fisheries for American tocarrying capacity. All aspects of the species’ life
shad,AIosa sapidissima.Dadswell(1979)estimated history indicate that shortnose sturgeon should be
incidental fishing mortality of adults in the Saint abundant in most rivers. Thus, the expected abun-
John River gill net fishery was less than 10% of total dance of adults in northern and north-central pop-
mortality. In the Connecticut River, Savoy & ulations should be thousands to tens of thousands of
Shake^3 estimated 2-25 adults were taken annually adults (Figure 4). Expected abundance in southern
by the American shad fishery, and some fish are also rivers is uncertain, but large rivers should likely
caught by sport fishers angling for catfish,Ictalurus have thousands of adults. In small southern rivers,
spp. Marchette & Smiley^8 also reported catch of periodic removal of even small numbers of adults
shortnose sturgeon by sport fishers in South Car- by poachers will probably make all other conserva-
olina. Recent evaluation of sturgeon bycatch in tion measures unsuccessful. Impacts of fishing by-
American shad gill net fisheries and shrimp trawl catch should be identified and reduced. In rivers
fisheries in South Carolina and Georgia found that where spawning migrations are blocked by dams.
gill net fisheries captured about 2% of the adults. Of long-term solutions should be found for passing mi-
those captured. 11% died and 15% were injured grants (if spawning habitat remains upriver). Be-
(Collins & Smith 1996). Even if spawning migrants cause spawning habitat requirements are known,
are released after capture by commercial fishers. the usefulness of creating artificial spawning areas
handling greatly disrupts their migration (Moser & should be investigated for spawning runs blocked
Ross 1994). by dams. Migratory movement patterns and river
Poaching of adults in southern rivers using gill reaches used for foraging and spawning of all pop-
nets and traps seems widespread. Although no esti- ulations should be identified and protected. Spawn-
mate of poaching exists. poachers captured 8 of 10 ing location and habitat should continue to be iden-
radio-tagged migrants below Pinopolis Dam on the tified, particularly in southern rivers. Acceptable
Cooper River (D. Cooke personal communication) spawning conditions for fish blocked by dams
and 11 adults were trapped in the upper Santee Riv- should be maintained. The effect of contaminants
er (M. Collins personal communication). Adults on shortnose sturgeon reproduction and survival
are extremely vulnerable to poaching because they are unknown and should be investigated in these
group together in concentration areas and a com- long-lived fish. Finally, long-term monitoring of
monly available inexpensive gear (gill nets) cap- population dynamics, abundance, and recruitment
tures them. is needed in all populations to establish trends.
Gill net fisheries bycatch and poaching are likely Using cultured fish for supplementing popula-
having a signifant impact on southern, but noton tion abundance or restoring extirpated populations
northern populations. The last attempt to estimate should be done carefully. Restoration should be at-
the effects of harvest on shortnose sturgeon was tempted only after suitable habitat conditions for
done more than 10 years ago using data from pop- all life intervals exist and a suitable donor stock is
ulations in the Saint John, Hudson, and Pee Dee riv- available. The Delaware River stock should prob-
ers (Boreman et aI.12). Given the new information ably be used to restore Chesapeake Bay rivers. This
on losses of fish to bycatch and poaching in south- restoration may be important to avoid long term ge-
ern rivers, the effect of fishing mortality on south- netic isolation between northern and southern seg-
ern populations should be reevaluated. ments of the range. Supplementary stocking of cul-
martin jones
(Martin Jones)
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