Resilient Sturgeon? the Susceptibility of Sturgeons to Environmental Stressors, Exploitation and Extinction

Sturgeons are poky at life: their heart beats slowly; they move deliberately, mature slowly, reproduce infrequently and are slow to die.  What does this say about their resilience to periods of directed exploitation or poor environments?    Misclassified as K-selected species, sturgeons epitomize periodic strategists adapted for infrequent favorable conditions.   Low mortality, long lifespan, iteroparity, and high fecundity all lead to a “storage effect” where the potential of strong recruitments persists in a single generation over multiple decades.  For example, Chesapeake Bay Atlantic sturgeon juveniles now swim where they had not been observed for >15 years.    Abundance of Hudson River shortnose sturgeon recently increased four-fold, likely in response to improved water quality.   On the other hand, subtle increases in juvenile and adult mortalities can disrupt the storage effect, making current threats such as incidental catch, vessel strikes, and power plant entrainment insidious deterrents to sturgeon recovery.     Still, the experience of past and recent recoveries of sturgeons jibes with their long-term capacity for persistence and recovery.  In some (but certainly not all) populations, this gives hope for active recovery strategies such as reduction in bycatch, river restoration, and improvements in water quality.