La Tour du Valat

Institut de recherche pour la conservation des zones humides méditerranéennes

Titre :	Using winter flounder growth rates to assess habitat quality across an anthropogenic gradient in Narragansett Bay, Rhode Island
Auteurs :	L. Meng, Auteur ; J. C. Powell, Auteur ; B. Taplin, Auteur
Type de document :	Article
Dans :	Estuaries (24(4) AUG 2001)
Article en page(s) :	576-584
Résumé :	We used growth rates of juvenile winter flounder Pseudopleuronectes americanus to assess anthropogenic influence on habitat quality at three sites in Narragansett Bay, Rhode Island. The upper bay site, Gaspee Point, had the highest population density and concentration of total nitrogen; human inputs decreased down bay. Growth rates of individually marked fish were measured in three 15-d experiments from June 8 to July 6, 1998 in 1-m(2) cages placed at upper, middle, and lower bay sites. Water temperature, salinity, dissolved oxygen (DO), and benthic food were also measured. Stable isotopes of nitrogen and carbon were measured in experimental fish as possible indicators of nutrient enrichment and to identify organic carbon sources. Growth rates were 0.22-0.60 mm d (1), with the highest average at the mid-bay site. Growth was initially fastest at Gaspee Point, but dropped off as DO concentrations fell. Step-wise multiple regression indicated that location (upper, middle, or lower bay) explained most of the variability in fish growth (40%). Coefficients of other significant variables indicated that fish grew faster at lower salinities, smaller sizes, and with decreased time that

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