ResourcesIdentification of Important Habitats in Coastal New HampshireChapter 21. Smooth FlounderThe smooth flounder, Pleuronectes putnami, is an estuarine flatfish
which is relatively common in Great Bay. Though occasionally taken by
fishermen, these fish are typically smaller than the more sought after
winter flounder. The following tables are components of a smooth flounder
habitat model. The information was compiled primarily
from a dissertation by Armstrong (1995) and by examination of conditions
associated with fish collection sites in Great Bay (Nelson et al. 1981,
1982) and the Seabrook/Hampton estuary. The model operates on four parameters: substrate, salinity, temperature,
and depth. The model indexes the relative suitability of each environmental
parameter on a 0 to 10 basis, with 10 being optimal and 0 being unsuitable.
These suitability index values are combined by computing their geometric
mean for each grid-cell in the study area. Thus, optimal habitat for any
life stagewould occur where the index values were the maximum for each
of the four inputs; no value is attributed to areas where any condition
is completely unsuitable. Suitability is calculated for each season, to
accommodate annual changes in salinity and temperature. Habitats were mapped for conditions needed by juveniles, by adults, and
for reproduction and larval stages. Smooth flounder occur in New Hampshire
estuaries throughout the year and are mobile, thus able to avoid seasonally
unsuitable conditions. Accordingly, juvenile (Figure
of Juvenile Habitat) and adult habitats (Figure
of Adult Habitat) were based on the average of suitability values
for all four seasons. The reproductive/larval habitats (Figure
of Spawning Habitat) were mapped as the maximum or most favorable
score of either winter or spring, in consideration of some flexibility
in the timing of reproduction. Smooth flounder overall habitat (Figure
of Habitat for Combined Life Stages) was mapped as the maximum score
for either juvenile, adult, or reproductive/larval habitat. This ensures
valuation for habitats which may support stages from and into which the
species may migrate to other coastal areas. SUBSTRATE PREFERENCES Sources: Armstrong 1995, Bigelow and Schroeder 1953, MacDonald et al. 1984. Substrate Suitability Index: 0 to 10 scale; 0 = unsuitable, 10 = optimal condition ADULT AND JUVENILE
REPRODUCTION, LARVAE
SALINITY PREFERENCES Source: Armstrong 1995. Salinity (ppt) Suitability Index: 0 to 10 scale; 0 = unsuitable, 10 = optimal condition ADULT
JUVENILE
REPRODUCTION, LARVAE
TEMPERATURE PREFERENCES Sources: Bigelow and Schroeder 1953, Targett and McCleave 1974. Temperature (C) Suitability Index: 0 to 10 scale; 0 = unsuitable, 10 = optimal condition ADULT
JUVENILE
REPRODUCTION, LARVAE
DEPTH PREFERENCES Sources: Armstrong 1995, Bigelow and Schroeder 1953, MacDonald et al. 1984, Targett and McCleave 1974; overlay of NHF&G fyke net collections with depth map. Depth (feet, mlw*) Suitability Index: 0 to 10 scale; 0 = unsuitable, 10 = optimal condition ADULT
JUVENILE
REPRODUCTION, LARVAE
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