Full ecoregional plan - Conservation Gateway

occurring in all EDUs and 28-32 of the 33 watersheds include common shiner, longnose dace,tessellated darter, banded killifish, redbreast sunfish, American eel, blacknose dace, and fallfish.These fish are associated with the widespread and common aquatic habitats of the region andappear to tolerate the ranges of climate and stream temperature that normally occurs across theregion. Although all these fish occur throughout the analysis area, some species such as whitesuckers, yellow perch, golden shines, and common shiners appear to be aquatic habitatgeneralists. They use a wide range of local habitats from creeks to small and medium rivers tolarge lakes and have ranges that extend significantly outside the region (Page and Burr 2001).Other species such as brown bullhead, brook trout, dace, fallfish, and tessellated darter preferspecific habitats that although specific, are widespread throughout the analysis region. Forexample, Brown bullheads need the deep water of large lakes and rivers, that occur in everyEDU (Williams 2002). Brook trout need cool, oxygen-rich creeks to medium rivers that are alsocommon habitats throughout the region. Blacknose dace, fallfish, and longnose dace prefer fastercurrent streams with gravel to rocky substrate. Blacknose and longnose dace prefer springs andcool, clear creeks with moderate to swift currents over gravel or rocks, with longnose dacepreferring slightly faster currents. Fallfish avoid small streams but prefer gravel, rubble bottomedpools and runs of small to medium rivers and lake margins. Certain widely distributed fish in thisregion such as banded killifish and tessellated darter prefer slower current waters that are alsocommonly found in this region. American eels are fish with a unique catadromous life historythat are widely distributed throughout the region. Non-native fish that occur in the regionincluded the bluntnose minnow, brown trout, cutlips minnow, fathead minnow, largemouth bass,pearl dace, pumpkinseed, rainbow trout, rock bass, round-whitefish, and trout-perch. Lake trout,rainbow smelt, and burbot were native in some of the watersheds and non-native in others.The increased numbers of species present in the Lower Connecticut EDU and Saco-Merrimack-Charles EDU in comparison to the Middle Connecticut, Upper Connecticut, and Cape EDUlikely represents the increased diversity of aquatic habitat niches within these EDUs, particularlytheir direct connection with the ocean. The Lower Connecticut and Saco-Merrimack-CharlesEDU have both diverse upland areas of habitat as well as significant sections of large, medium,and small coastal rivers where estuarine habitat is abundant and where there are access points foranadromous and catadromous species. The Cape Cod EDU has direct connection with the oceanand estuarine habitat; however, the sizes of rivers in the Cape Cod EDU are quite small; there areno size 3 rivers and only 5 examples of size 2 rivers. The Cape Cod EDU is also quite uniform inits physical habitat diversity that may also limit the number of species that can find adequatehabitat in this EDU. The dominance of higher gradient stream systems, higher elevations andcolder temperatures, and the lack of estuarine habitat limits the aquatic habitat niches available inthe Middle and Upper Connecticut EDUs. Certain species likely experience physiological limitsto the colder climate in these EDUs which may explain the lower number of species in theseEDUs.REVISED 6/2003AQUA-RESULTS-7