Comparative demography of skates: life-history correlates of productivity and implications for management

PLoS One. 2013 May 31;8(5):e65000. doi: 10.1371/journal.pone.0065000. Print 2013.

Abstract

Age-structured demographic models were constructed based on empirical estimates of longevity and maturity for five deepwater Bering Sea skates to investigate how observed differences in life history parameters affect population growth rates. Monte Carlo simulations were used to incorporate parameter uncertainty. Estimated population growth rates ranged from 1.045 to 1.129 yr(-1) and were lower than those reported for other Alaskan skates and most chondrichthyans. Population growth rates of these and other high-latitude skates increased with relative reproductive lifespan, but displayed no significant relationship with body size or depth distribution, suggesting that assemblage shifts may be difficult to predict for data-poor taxa. Elasticity analyses indicated that juvenile and adult survival had greater per-unit effects on population growth rates than did egg-case survival or fecundity. Population growth rate was affected more by uncertainty in age at maturity than maximum age. The results of this study indicate that if skates are deemed to be a management concern, gear modifications or depth-specific effort controls may be effective.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Animals
  • Computer Simulation
  • Environment
  • Female
  • Longevity
  • Models, Statistical*
  • Monte Carlo Method
  • Population Dynamics
  • Sexual Maturation
  • Skates, Fish / growth & development*

Grant support

Funding for this project was provided by the North Pacific Research Board (www.nprb.org/) under project 715 and a Graduate Student Research Award, and the David and Lucile Packard Foundation (http://www.packard.org/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.