MEPS 291:301-305 (2005)  -  doi:10.3354/meps291301

Application of the nursery-role hypothesis to an estuarine fish

Richard T. Kraus1,*, David H. Secor2

1Department of Marine Biology, Texas A&M University. 5007 Avenue U, Galveston, Texas 77551, USA
2University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory, One Williams Street, Solomons, Maryland 20688, USA

ABSTRACT: In this paper, we address a recent article by Beck et al. (2001, Bioscience 51:633–641), in which it was proposed that the value of a juvenile fish habitat could be most efficiently measured as the production of adults from each juvenile habitat on a per area basis. Based upon retrospective microchemical analysis of otoliths, we calculated this metric (nursery value) for tidal freshwater and brackish littoral habitats of an estuarine fish, white perch Morone americana, in the Patuxent River estuary, Maryland (USA). In dominant year-classes of the population, brackish habitats had the highest nursery value, whereas in all other year-classes, freshwater habitats had the highest nursery value. This result highlights the importance of inter-annual variability in habitat use, and consequently presents a challenging trade-off for applying the nursery-role hypothesis to facilitate habitat conservation and management. Despite this limitation, the nursery-role hypothesis provides an enriched and much needed perspective on population connectivity.

KEY WORDS: Nursery-role · Habitat conservation · Estuarine dependency · Otolith chemistry · Chesapeake

Full text in pdf format