IV. CONCLUDING COMMENTS:

Lobster behavior will largely determine whether or not various life history stages are present at the site of the new MWRA outfall. If the lobsters are not now and have never been at the site, then investigating the consequences of treatments at the site on them would be a complete and utter waste of time. Thus, determining the presence or absence of the various life stages of lobster at the outfall site is the most pressing matter. Depending on the behavior of the lobsters, the outfall may have some effect or none at all. However, the outfall may have other effects that would influence lobsters -- for example, if it resulted in a reduction of food resources used by the lobsters, then this might be the reason that lobsters are found in lower abundance near outfalls. Food species could be affected by a number of things, but the three of greatest concern would be: freshwater effects (many animals cannot survive in reduced salinity or are repelled by it), flow effects, and toxicity effects. Freshwater and flow effects do not seem to have been studied thus far, but toxicity effects are already being assessed via EPA protocols and indicator species. Obviously, the kind of long-term studies that need to be pursued at outfall sites are ones that look at trophic food web changes as opposed to a single species, such as the lobster. Such data may already be available from current MWRA outfall monitoring programs and should be used to determine the likely changes in fauna at the new outfall site.

Although the recent Boston Globe article (from Thursday 16 April, 1998, page 1) suggested that lobsters were completely absent from the outfall areas in Lynn, Salem, Scituate, and Hull, landings in Massachusetts Bay indicated that they are not absent, but are reduced compared to the early 1990's level. The reduction in landings is likely due to overfishing and changes in fauna (their food sources). Subsequent to improving the quality of their effluents by removing many organics, the cities of Lynn, Salem, Scituate, and Hull, have seen the fauna at the outfall sites return to the types seen before effluents were used (in other words it has been restored to historic types) and perhaps some of the food resources of lobsters have been lost. Thus you would not expect lobsters to be as concentrated in outfall areas (former hotspots for fishing) as in the past.

Bruce Estrella's (of MADMF) 17 year time series shows that Massachusetts Bay areas sampled have the highest exploitation rates, highest fishing mortalities, lowest mean size of lobsters landed and lowest percentage of ovigerous females compared to adjacent areas of Cape Ann and Cape Cod Bay. Approximately 93% of the legal catch in inshore regions (Cape Ann south to Cape Cod and Buzzards Bays) consists of new recruits to the fishery (83-94 mm CL) (Estrella and Armstrong, 1994). Clearly the resource in this inshore region in Massachusetts is overexploited and this alone could result in reduced landings in Boston Harbor. It is difficult to tease apart the various factors that may affect landings; however, landings by county or region throughout the state could be individually plotted for the past decade to look for trends. If the trend is of decreased landings in counties or regions with and without outfall sites present, then this is a strong argument that overfishing, not outfall effluent, is causing the reduction in lobster numbers. Additional information that would be needed for a complete assessment of the trends would be number of traps fished per lobstermen per area and number of lobstermen fishing in a particular area.

In addition to the above-mentioned possibility for lobster disappearance in outfall sites (food source reduction, flow rates, freshwater repulsion, overfishing), the areas listed in the Boston Globe article of 16 April 1998: Lynn, Salem, Scituate, and Hull -- have experienced enormous coastal development over the last 20 years and those of us who sample for lobsters in coastal regions know the following: the shallow coastal regions are THE nursery areas for lobsters. If you damage these, you damage the future of the fishery because this is where the juveniles come from to enter the fishery. Every time you dredge, plow over, build around (causing siltation), etc. these areas, you are negatively impacting future generations of fished lobsters. Most of us working out in the field believe that this is the single most important threat to the future of the fishery. If lobstermen and the industry want to get up in arms about something, then coastal development is it. Unfortunately it is often easier to aim the blame at larger targets (like the governmental agencies such as MWRA, EPA, DMF, or NMFS), than it is to concentrate the blame on the thousands of developers and home owners who want to have houses with an ocean view and who don't care if they destroy coastal habitat to get that view.

Pollution is a serious issue and an emotional one -- and it should be. We have, too often, treated our ocean waters as dumping grounds and as a result have seen increased incidences of public warnings about what we shouldn't eat and where we shouldn't swim. However, the issues surrounding the reasons for changes in lobster abundance and distribution in Massachusetts Bay are very complex (particularly those concerning settling postlarvae) and we don't yet have the picture in nonpolluted or polluted areas. As with any scientific study, this situation requires pinpointing the problems and fully researching the existent literature in order to avoid a wasteful duplication of effort. A careful review of the literature allows one to then ask the right questions, based on logical hypotheses about probable events. The current situation with regard to lobsters and the future MWRA outfall has not determined the correct questions due to a basic lack of knowledge of larval, postlarval, and YOY behavior. Some studies are warranted, but these should involve (1) determination of the presence (or absence) of larvae and competent-to-settle postlarvae in the waters overlying the outfall diffusers; (2) determination of ovigerous female movement patterns; and (3) assessment of chronic exposure to harmful organics on egg masses carried by females -- if their movement patterns warrant it. Toxicity tests on larvae are not warranted, given that we have considerable information on their sensitivity to many compounds and given that other, more sensitive indicator species are being used for continued monitoring. Intensive diver surveys and cobble emplacement studies are also not warranted until it is determined that competent postlarvae are present for potential benthic recruitment. If diver surveys are undertaken in lieu of neustonic sampling, then agreement about what consitutes a "no threat" situation must be made beforehand (in other words, if the survey finds no lobsters present of sizes 5-25 mm CL, then there must be agreement that this is a sufficient test, rather than the result of inadequate sampling). Duplication of toxicity tests and repetitive benthic surveys at this time would be a waste of taxpayer funding. However, in the event that YOY lobsters are found near the outfall site, then further testing would be warranted.

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