The comparative studies be conducted in the Kennebec, Sheepscot, Damariscotta and Penobscot River embayments. Changes in current velocities, mixing, temperature, salinity and nutrients should be examined on seasonal bases over spring-neap tidal cycles using research vessels and low altitude remote sensing techniques from aircraft. abundance, distribution and diversity of estuarine plants and animals should also be examined using ground level and remote sensing techniques. These studies will provide fundamental insight into how the physics, chemistry and biology will change in Maine estuaries. Primary production of organic food matter by phytoplankton provides the energy which drives biological growth in the Gulf of Maine. Since vertical mixing of water masses is generated to a large extent by tidal currents, an increase in tide range would generally increase mixing. This increased mixing would bring more nutrients into surface waters to yield higher levels of primary productivity. It is necessary to know how, where and when primary productivity will be changed. This problem may be approached by examining vertical mixing and plankton production by satellite imagery and the use of research vessels. The influence of tidal range could be assessed by studies conducted over spring-neap tidal cycles on a seasonal basis. 2. Biological production in major fisheries regions Dr. Greenberg's tidal model predicts that there would be a merging of the vertically well-mixed areas over Nantucket Shoals and Georges Bank. Such an event could significantly change current patterns around these productive fishing grounds resulting in altered fisheries production. The finer grid patterns obtained for Dr. Greenberg's model, together with satellite and cruise data, could be used to study plankton densities and water movements across and around Georges Bank and Nantucket Shoals. Seasonal studies over spring-neap tidal cycles would help us understand major changes in productivity which might result from a 10% increase in tidal range. It is suggested that workshops be sponsored to allow scientists, supporting agencies and other interested parties to exchange ideas and follow scientific progress. Scientific efforts will clearly involve a great number of diverse but interrelated studies. It is essential that all investigators periodically organize their data for presentation to colleagues within the program as well as other scientists. This will also serve to critically evaluate scientific programs. We envision the need for 5 three-day workshops where all program scientists will participate. These workshops will supplement the more frequent assembly of groups of scientists who collaborate closely. 5 V. AGENCIES TO GUIDE, SUPPORT AND EVALUATE SCIENTIFIC STUDIES It is of critical importance that all scientific efforts be well planned, adequately supported and critically evaluated. We suggest that a committee be established by the National Academy of Sciences to organize and oversee the scientific research. Spencer Apollonio, Commissioner of the Maine Department of Marine Resources, is in the process of having Governor Brennan request the National Academy of Sciences to establish a committee to guide this research. Charles S. Yentsch, Director of the Bigelow Laboratory for Ocean Sciences, has already contacted the Academy and has indicated that the Academy would be willing to establish such a committee. Research support might be handled through NOAA, the federal agency most intimately involved with oceanographic and coastal problems. NOAA could receive funds to support scientific efforts and provide some aid to critically evaluate research programs and their results. It is clear that both Canada and the U.S. will have an interest in this project. U.S. and Canadian agencies and scientists should therefore collaborate on the planning and execution of the needed research. It is equally clear that the scientific results will reflect the expertise of individual scientists. Only the most highly qualified researchers should be approached to conduct the necessary work. Possible Impact of Large-Scale Tidal Power Developments in the Upper Bay of Fundy on Certain Migratory Fish Stocks of the Northwest Atlantic ABSTRACT Dadswell, M.J., G.D. Melvin, P.J. Williams and Gail S. Brown. 1983 Possible impact of large-scale tidal power developments in the upper bay of Fundy on migratory fish stocks of the Northwest Atlantic. Can. Tech. Rep. Fish. Aquat. Sci. 000.000-000 Megatidal embayments of the upper Bay of Fundy are occupied in summer by large numbers of feeding fish, particularly alosids. The American shad present contribute to a local fishery. Tagging experiments indicate these shad are drawn from all stocks native to rivers on the North American Atlantic Coast from Florida to Quebec and a large portion of the total western Atlantic adult shad stock, estimated at 3.5 x 107 individuals in 1981, may be present in the upper Bay of Fundy each summer. Construction of large-scale tidal power structures on these embayments will alter the habitat by changing turbidity and temaperature regimes and may alter migratory routes of the species concerned. Additionally repeated passage through the turbines may cause significant mortality. Key Words: megatidal, alosids, American shad, migration, populations, |