Sturgeon Endangerment: Should we be surprised that no sturgeon species are yet extinct? Sturgeons co-existed with dinosaurs and have survived the cataclysmic ecological effects of asteroid blasts. Why then should we be concerned? The conundrum of sturgeon is that despite their resiliency through evolutionary time, they are particularly sensitive to harvest and habitat degradation (from Secor et al. 2002). Worldwide, many sturgeon populations are in jeopardy of extirpation in the coming decades. In the Caspian Sea, a ban on most caviar fisheries was imposed in 2001 to protect beluga, Russian, and stellate sturgeons. Here in North America, sturgeons were second only to marine Sebastes (Scorpaenidae) in the number of species categorized as either threatened or endangered (Musick et al. 2000). In trying to restore population abundances, we are quickly learning that much more is required than merely protecting the species from further harm. How to promote recovery remains largely illusive - a vexing conundrum in the face of the real likelihood that during many of our careers, sturgeon populations will continue to go extinct ....

A long-term goal of our laboratory is to participate with federal, state, and international cooperators in programs of sturgeon restoration (in the Chesapeake Bay) and sturgeon conservation elsewhere. Current efforts have been devoted towards determining factors that most contributed to Chesapeake Bay sturgeon declines and limits to their recovery. These investigations have led to several pertinent issues/constraints:

• Sturgeons are among the most oxyphilic (susceptible to low oxygen) species in the Chesapeake Bay. We are working with the Chesapeake Bay Program to revise water quality criteria in the Chesapeake Bay to be more protective of sturgeons ....

  	Bay Program www summary ....

  	Bay Program Report: Historical Abundance of Atlantic Sturgeon [1.3 Mb; will open in a new window]

  Bioenergetics models indicate that habitats for both sturgeons are greatly reduced and fragmented in the Chesapeake Bay due to limits imposed by modern era summer time hypoxic conditions.

  	E.N. Dissertation Bioenergetics Modeling and Assessment of Suitable Habitat for Juvenile Atlantic and Shortnose Sturgeons in the Chesapeake Bay [12.6 Mb; will open in a new window]

  In contrast to most other sturgeon populations, shortnose sturgeon (shown here) have recently experienced a remarkable recovery in the Hudson River

  
  

• Sturgeons were once abundant in the Chesapeake Bay, with adults numbering in the hundreds of thousands. Overfishing reduced their numbers in the late 19th Century, but over the past century there has been no recovery of abundances. Shortnose sturgeon are extirpated from the Chesapeake Bay, and Atlantic sturgeon are extirpated in Maryland waters.

  	Roe to Ruin: The Decline of Sturgeon in the Caspian Sea and the Road to Recovery

• Due to incredibly high demand for caviar, regional sturgeon conservation requires international conservation and strict harvest regulations against threatened sturgeon populations. We are consulting with government and conservation groups to evaluate the sustainability of sturgeon harvests in the Caspian Sea.

  	CITIES 2002 Report: Status of Caspian Sea Sturgeons [will open in a new window]

Niklitschek, E.S. and D.H. Secor. 2010. Experimental and field evidence of behavioral habitat selection by juvenile Atlantic (Acipenser oxyrinchus) and shortnose (Acipenser brevirostrum) sturgeons. J. Fish Biol. 77: 1293-1308.

Niklitschek, E.S. and D.H. Secor. 2009. Dissolved oxygen, temperature and salinity effects on the ecophysiology and survival of juvenile Atlantic sturgeon in estuarine waters: I. Laboratory Results. J. Exp. Mar. Biol. Ecol. 381, Suppl. 1: 150-160.

Niklitschek, E.S. and D.H. Secor. 2009. Dissolved oxygen, temperature and salinity effects on the ecophysiology and survival of juvenile Atlantic sturgeon in estuarine waters: II. Model development and testing. J. Exp. Mar. Biol. Ecol. 381, Suppl. 1: 161-172.

Woodland, R.J., D.H. Secor, and E.J. Niklitschek. 2009. Past and future habitat suitability for the Hudson River population of shortnose sturgeon: a bioenergetic approach to modeling habitat suitability for an endangered species. Am. Fish. Soc. Symp. 69: 589-604.

Woodland, R. and D.H. Secor. 2007. Year-class strength and recovery of endangered shortnose sturgeon in the Hudson River, NY.  Trans. Am. Fish. Soc. 136:72–81

Gross, M.R., J. Repka, C.T. Robertson, D.H. Secor and W. Van Winkle. 2002. Sturgeon conservation: insights from elasticity analysis. Am. Fish. Soc. Symp. 28: 13-30.

Secor, D.H. 2002. Atlantic sturgeon fisheries and stock abundances during the late nineteenth century. Am. Fish. Soc. Symp. 28: 89-98.

Secor, D.H., P.J. Anders, W. Van Winkel and D. Dixon. 2002. Can we study sturgeons to extinction? What we do and don't know about the conservation of North American sturgeons. Am. Fish. Soc. Symp. 28: 3-10.

	Can we study sturgeons to extinction? [96 Kb; will open in a new window]

Van Winkle, W., P.J. Anders, D.H. Secor, and D. Dixon (Eds.). 2002. Biology, Protection, and Management of North American Sturgeon. Am. Fish. Soc. Symp. 28, 258 pp.

Secor, D.J. and E.J. Niklitschek. In press. Sensitivity of sturgeons to environmental hypoxia: A review of physiological and ecological evidence. In: Fish Physiology, Toxicology, and Water Quality. Proceedings of the Sixth International Symposium, La Paz, MX, 22-26 Jan. 2001. U.S. Environmental Protection Agency Office of Research and Development, Ecosystems Research Division, Athens, GA.

Secor, D.H., V. Arevyev, A. Nikolaev, and A. Sharov. 2000. Restoration of sturgeons: Lessons from the Caspian Sea sturgeon ranching program. Fish and Fisheries 1: 215-230.

Secor, D.H., E. Niklitschek, J.T. Stevenson, T.E. Gunderson, S. Minkkinen, B. Florence, M. Mangold, J. Skjeveland and A. Henderson-Arzapalo. 2000. Dispersal and growth of yearling Atlantic sturgeon Acipenser oxyrinchus released into the Chesapeake Bay. Fish. Bull. 98: 800-810.

Stevenson, J.T. and D.H. Secor. 2000. Age determination and growth of Hudson River Atlantic sturgeon, Acipenser oxyrinchus. Fish. Bull. 97: 153-166.

Secor, D.H. and J.R. Waldman. 1999. Historical abundance of Delaware Bay atlantic sturgeon and potential rate of recovery. pp. 203-217. In: J.A. Musick [Ed.], Life in the Slow Lane: Ecology and Conservation of Long-Lived Marine Animals. Amer. Fish. Soc. Symp. 23, Washington, DC.

Waldman, J.R. and D.H. Secor. 1999. Caviar trade in North America: An historical perspective. pp. 52-64. In: D. Williamson [Ed.], Proceedings of the Symposium on Harvest, Trade, and Conservation of North American Sturgeon and Paddlefish.

Secor, D.H. and T.E. Gunderson. 1998. Effects of hypoxia and temperature on survival, growth, and respiration of juvenile Atlantic sturgeon, Acipenser oxyrinchus. Fish. Bull. 96: 603-613.