Cobscook Bay Inventory

Cobscook Bay
Outer Cobscook Bay with Shackford Head in the foreground. Photo by Tom Trott.
Project Summary:

This work produced the definitive list of the over eight hundred species of macroinvertebrates that have been or are present in Cobscook Bay during the last one hundred sixty years.


This project is a model for accurate determination of historical species assemblages to serve as a basis for comparison with present day biodiversity data and for evaluating change in ecosystems. It is also a testament to both the difficulty and importance of such work – the project took four years and the expertise of nearly 30 taxonomists worldwide. Already this work has proved valuable as a basis for comparison with present day species assemblages.

  • Thomas Trott, Suffolk University and Friedman Field Station
  • This project received no outside funding

Cobscook Bay, 2000 -2004

Project Detail:

This project assembled a list of marine macroinvertebrates observed in Cobscook Bay over a period of 162 years. Over 800 species were documented from present-day research, published literature, museum collection records, electronic databases, graduate student theses, and species collection lists from invertebrate zoologists. Nearly all these records were reviewed by taxonomists to verify the listing of currently accepted names with their synonyms. This register has therefore become a resource for the North Atlantic Register of Marine Species.

The importance of establishing baselines for detection of change is of obvious necessity, yet documenting species assemblages on any geographical scale is not generally attractive to funding agencies. The hundreds of hours required to complete this four-year project were supported entirely by the volunteer effort of the author. Nearly 30 taxonomists of international recognition donated their time freely throughout the various phases of this work to review species names and their synonymies. The taxonomic quality of this document would never have been achieved without their generosity. The opportunity for publishing species lists in a peer reviewed journal is as rare as receiving funding for assembling a baseline. Were it not for the coincidental completion of the list while a special volume on ecosystem modeling of Cobscook Bay was assembled, this work may have been published in a low visibility specialty publication at best.

The utility of this register was demonstrated by comparing present-day species assemblages at special locations, i.e., critical areas, in Cobscook Bay with species documented 30 years ago. Many historically common species have become rare or absent. These results draw attention to the importance of having baseline data to detect changes with any degree of certainty.

Through funding awarded to the author by the History of Nearshore Program created by NaGISA and HMAP, the Cobscook Inventory will become part of the NaGISA database. Ultimately, this information will become part of OBIS.

  • Trott, Thomas J. 2004. Cobscook Bay inventory: A historical checklist of marine invertebrates spanning 162 years. Northeastern Naturalist 11 (Special Issue 2): 325-354. (PDF -1334K) »
    (PDF of this paper generously made available by the Northeastern Naturalist.)
  • Trott, Thomas J. 2004. Late 20th-Century qualitative intertidal faunal changes in Cobscook Bay, Maine. Northeastern Naturalist 11 (Special Issue 2): 325-354. (PDF – 7476K) »
    (PDF of this paper generously made available by the Northeastern Naturalist.)
More Information:

North Atlantic Register of Marine Species