Do Juvenile White Perch Morone americana Grow Better in Freshwater Habitats of the Blackwater River Drainage (Chesapeake Bay, MD, USA)?

作者：Newhard Joshua James^*; Love Joseph William; Gill John

来源：Estuaries and Coasts, 2012, 35(4): 1110-1118.

DOI：10.1007/s12237-012-9512-0

• Fish growth
• CART
• Age
• Nurseries
• Climate change

Increasing rates of freshwater habitat loss in the Chesapeake Bay (and elsewhere) have renewed interest in the role of freshwater in population integrity for euryhaline fishes. Freshwater habitats may be important nurseries for juveniles of anadromous species. Using length-weight residuals and scales, we determined if body condition and growth of juvenile (< 120 mm total length) white perch Morone americana (a semi-anadromous species) differed between brackish and freshwater tributaries within the Blackwater River drainage (Chesapeake Bay Watershed, U.S.A.). We then examined how monthly variation in body condition varied with monthly variation in selected environmental factors. Body condition differed between tributaries and was greater in freshwater (specific conductivity < 0.45 mS) than brackish water when water temperature was greater than 9.6A degrees C. White perch growth rates did not differ between tributaries, except for a short time during summer or early fall. Some anadromous fishes may spawn in freshwater to promote greater body condition, thereby ensuring a quality contingent of individuals for the population. With continued loss or impairment of freshwater habitat, the availability of nurseries for juvenile white perch will be reduced and reduce the number of quality juveniles recruiting to the adult population.

• 出版日期2012-7