Armstrong. Distribution and abundance of Pleuronectes putnami and Pleuronectes americanus 
423 
Sampling date 
Figure 7 
Mean number of winter flounder, Pleuronectes americanus , caught per ten 
minute tow at three sites along a salinity gradient in Great Bay Estuary, 
New Hampshire, May 1989-September 1991. Site l=oligohaline; site 
2=mesohaline; site 3=polyhaline. Error bars are one standard error of the 
mean. 
at higher temperatures and light intensities (see re- 
views in Klein-MacPhee, 1978; Casterlin and Reynolds, 
1982). It is especially interesting that winter flounder 
showed relatively little use of the intertidal flats. Tyler 
(1971), Wells et al. (1973), and Black and Miller (1991), 
however, found that winter flounder used intertidal 
flats extensively. Their studies took place in areas of 
higher salinity where no smooth flounder occurred. 
Their finding suggests that competition with smooth 
flounder may be a possible reason for the near absence 
of winter flounder from the intertidal flats habitat in 
Great Bay. Targett and McCleave ( 1974) found that the 
tidal mudflats in Montsweag Bay, Maine, were domi- 
nated by smooth flounder, whereas Fried (1973) found 
that the channel areas in the same estuary were domi- 
nated by winter flounder. Fried ( 1973) felt that the tidal 
mudflats offered smooth flounders a refugium from 
competition with winter flounder and that winter floun- 
