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patterns (i.e., boundary conditions) from the Gulf of Maine will be used and how will the 

 predicted current patterns from the model and their effects on nutrient and toxin transpon be 

 analyzed? How are these related to the endangered species distributions? Are the species listed 

 in the Plan the only endangered species in the Bays? 



Recommendations for Improvement of the Plan 



1) The hypotheses should be much more specific regarding the particular species to be studied, 

 where and when they live in the bays, and the mechanisms to be examined regarding transpon 

 of toxins or other alterations of their habitat 



2) A thorough literature review should be done in order to give the study a clearer focus on the 

 endangered species and the specific mechanisms by which they may be impacted. 



3) Do not rely completely on literature information; the needed information may not exist. 

 Design fiel, laboratory, and modeling studies to address critical questions. 



4) Incorporate a biological model of plankton dynamics in the USGS model to provide more 

 realistic assessments of fates of nutrients and toxins and their effects on food chain dynamics. 

 Two types of modeling are suggested including: 1 ) simple food chain models containing 3-4 

 compartments such as nutrients, phytoplankton, zooplankton, and detritus, and 2) population 

 models of selected species including the endangered species and key species affecting their 

 survival such as dominant prey species. The simple food chain models coupled with the physical 

 mode! will provide insights into the first order effects of the spread of pollutants through the food 

 chain in time and space. Such food web models will allow testing the effects of rates of nutrient 

 uptake, grazing, cell and detrital sinking, decomposition, and resuspension on plankton production 

 rates. Population models applied to key species should be used to examine effects of various 

 biological and physical forcings on the projected population dynamics including lethal and 

 sublethal effects of toxins and food (or other resource) availability. By keeping both types of 

 models as simple as possible and focussed on specific questions and processes, the number of 

 parameters which must be estimated remains small and interpretation of results is straightforward. 



5) Specify the rime-space scales and regions to be studied with respect to each of the endangered 

 species. Specify physical, chemical, and biological forcings to be used in the modeling. 



6) Consult with a statistician to design an statistically appropriate protocol for assessing the 

 impact on each endangered species. 



7) A study of the role of the benthos in the accumulation and transpon of pollutant materials 

 that may impact the endangered species should be examined. Potential effects include direct 

 impact on benthic organisms which may be eaten by the endangered species, anoxia resulting 

 from eutrophication of the habitat, and resuspension of contaminated sediments by wind mixing 

 events. One scenario is that Cape Cod Bay could serve as a large settling basin for outfall 

 particulates, which, over long time scales (eg, > 20 years) could accumulate in significant 



