Appendix 2, continued. Estuary notes 



• Kennebec/Androscoggin Rivers: This system was 

 differentiated from the large estuary depicted in origi- 

 nal NEI map 1.07 (Sheepscot Bay) due to its distinct 

 hydrology. It is separated from the Sheepscot estuary 

 by Upper Hell Gate on the Sasanoa River and by the 

 marshland at the southern end of Hockomock Bay. In 

 addition, the seawater and mixing zones of the 

 Kennebec/Androscoggin Rivers are incorrectly de- 

 picted in the NEI as extending through Merrymeeting 

 Bay. Squiers (1 990) indicates that the huge volume of 

 fresh water emanating from these systems creates a 

 tidal freshwater lens extending through the bay to just 

 above Chops Point. Furthermore, LarsenandDoggett 

 (1 976) report that the bottom salinity just 7 miles from 

 the river mouth was 24 ppt in August (low flow season). 

 This suggests that the mixing zone extends through 

 most of the lower Kennebec, from Merrymeeting Bay to 

 Squirrel Point. Head of tide is at the dam in Augusta, 

 and the system's seaward boundary is a straight line 

 from Indian Point to Small Point. Refer to NOAA chart 

 #13293 for help in identifying the landmarks men- 

 tioned. 



• Wells Harbor: Although this estuary is relatively 

 smaller than the other North Atlantic estuaries consid- 

 ered, it was added to the NEI due to its importance as 

 a National Estuarine Research Reserve. We consider 

 the Wells Harbor system to consist of the Webhannet 

 and Little River watersheds (Ayvazian et al. 1992, 

 Ward 1 993). Theseare both shallow, bar-built systems 

 connected by a small marsh behind Laudhaum Beach. 

 Both seawater (> 25 ppt) and mixing zones (0.5-25 ppt) 

 were considered to be present for the ELMR analysis, 

 however, a tidal fresh zone was not included due to its 

 relatively small surface area. Refer to NOAA chart 

 #13286 for more information. 



• Merrimack River: This estuary is not considered to 

 have a seawater zone according to NEI map 1.11 

 (Merrimack River) due to the extreme fluctuations in 

 salinity at its shallow mouth. Species diversity is high- 

 est closest to the marine waters just outside of the 

 mixing zone, which can range from 25 to 5 ppt over a 

 tidal cycle. The primary habitats in the mixing zone are 

 tidal flats and the daily freshwater inflow is relatively 

 high. Changes from the original NEI map are that the 

 mixing zone is considered to extend from the mouth of 

 the river to Pow Pow River, and that the head of tide is 

 now considered to be approximately 3000 m north of 

 Haverill. Referto NOAA chart #1 3282 or 1 3274 for help 

 in identifying these landmarks. 



• Massachusetts Bay, Boston Harbor and Cape 

 Cod Bay: NEI map 1.12 (Boston Bay) shows the 

 delineation for Boston Harborand NEI map 1.1 3 shows 

 Cape Cod Bay. Due to its regional importance and 

 distinct hydrography, Massachusetts Bay was added 



to the ELMR database with Boston Harbor considered 

 as a sub-estuary of this system. Massachusetts Bay 

 and Cape Cod Bay are considered to be large seawa- 

 ter embayments functioning as estuaries. We realize 

 that there are undoubtedly small mixing and tidal fresh 

 zones in the areas not included in the NEI delineations, 

 but these are not considered due to their relatively 

 small surface areas. The larger Massachusetts Bay 

 "ecosystem" is sometimes considered to include Mas- 

 sachusetts Bay proper, Boston Harbor and Cape Cod 

 Bay with some of the freshwater inflow coming from the 

 Merrimack River (Townsend et al. 1 991 ). These three 

 areas are separated to present the fisheries informa- 

 tion on a somewhat finer scale. For ELMR purposes, 

 Massachusetts Bay is considered to be the area from 

 the mouth of Boston Harbor to a line drawn from 

 Eastern Point of Gloucester Harbor to Brant Rock to 

 the south. Refer to NOAA chart #13267 for help in 

 identifying these landmarks. 



Literature Cited 



Anonymous. 1991. Estuary profile series. Maine 

 Coastal Program, Maine State Planning Office, Au- 

 gusta, ME. 



Ayvazian, S.G., L.A. Deegan, and J.T. Finn. 1992. 

 Comparison of habitat use by estuarine fish assem- 

 blages in the Acadian and Virginian zoogeographic 

 provinces. Estuaries 15(3):368-383. 



Berril, M., and D. Berril. 1 981 . A Sierra Club naturalist's 

 guide to the North Atlantic coast: Cape Cod to New- 

 foundland. Sierra Club Books, San Francisco, CA. 464 

 P- 



Briggs, J.C. 1974. Marine zoogeography. McGraw 

 Hill series in population biology. McGraw Hill Book Co., 

 New York, NY. 475 p. 



Gosner, K.L. 1 971 . Guide to identification of marine 

 and estuarine invertebrates: Cape Hatteras to the Bay 

 of Fundy. John Wiley and Sons, Inc., New York, NY. 

 693 p. 



Larsen, P.F.andL.F. Doggett. 1976. The salinity and 

 temperature distributions of selected Maine estuaries. 

 Bigelow Laboratory Contrib. No. 2-76 . Maine State 

 Planning Office, Maine Coastal Program, Augusta, 

 ME. 



McAlice, B.J. 1977. A preliminary oceanographic 

 survey of the Damariscotta River estuary, Lincoln 

 County, Maine. Univ. Maine, Ira C. Darling Center, 

 Walpole, ME. 17 p. 



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