Environmental Monitors on Lobster Traps
Progress Report Due1 January 2004

Phase I Temperature (Completed in 2002)

More than a hundred ONSET temperature probes were purchased and distributed to lobstermen in 2001. The majority of these "TidBit" units are still in use today and, according to the manufacturers specification, should survive another year or two.  Approximately 25 units were damaged in the field so that, while the data was saved, these instruments are no longer useable.   On only one occasion was the data actual lost to damage. On occasions where several units are collected together for downloading sessions,  a calibration bath is conducted to test for instrument performance/biases.  This has been conducted on four occasions and the results are documented under "Probe Calibrations/Comparisons" section of the administrators manual at http://emolt.org.  Except for two specific probes, the checks have been satisfactory with biases within the specifications of the units. 

For complete descriptions of this phase of the project to date, see sections such as "Results from the Field" and "eMOLT updates/reports" on the emolt.org site.  This first phase of the project has been the most successful in terms of  the quantity of data collected and participants involved.  It is hoped that this phase will be maintained in a "long-term monitoring" sense and that it can be incorporated into funded "ocean observing systems" in the future. 

Phase II Salinity (Subcontract #02-579)

The final report for the salinity phase is in preparation and due 15 August 2004.   Analysis of the time series data in underway and reported there and can be viewed at www.emolt.org..  While the experiment was carried out as expected and several lobstermen participated by collecting time series,  the results are still uncertain at the time of this writing.   The primary difficulty is in distinguishing  real oceanographic signals from instrument noise due to potential fouling of the conductivity cell by  fine-grain bottom sediment.   While one instrument is apparently lost and one is still deployed ,  four have been recovered and are currently being refurbished/recalibrated according to plan.  In the future it is hoped that these instruments can be deployed by lobstermen again with a revised mooring configuration.  In order to avoid contamination by sediment, the instrument may need to be suspended well above the sea floor either with a flotation devices or tripod  cages.  It may be that the instruments can be deployed  directly on traps but only in hard-rock-bottom environments,  free of fine grain sediments. 

Given the limitations of the instruments in all bottom types,we are now discussing the possibility of using these instruments for particular process studies in the future.For example, we are investigating the very intriguing possibility that some of the geological formations associated with hard-rock-bottoms off the coast of Maine may be the site of submarine freshwater discharges and have arranged to test this hypothesis in coordination with BowdoinCollege this summer. This will require the temporary use of 2-3 Microcats for a period of 2-3 months.  If we succeed in validating this phenomenon we may then seek the help of lobstermen working near similar formations. We may also be are seeking out opportunities with other industry members to deploy salinity probes for investigating the recent phenomenon in the Merrimack River which lead to cod closure in Massachusetts.

Phase III Data Management Centers( Subcontract #03-659)

The final report for this phase is in preparation and due 15 February 2004. Obviously, a project of this nature with over hundred individuals contributing to the database requires efficient and reliable management strategies.  The process has evolved from the first year and routine standards are now finally taking hold.  The most difficult aspect of the project is not the collection of physical data but the metadata (ie mooring logs) associated with each deployment.  From the beginning we have implemented a number of different options to record this information including the use of the Thistle Marine Electronic Logbooks.  These units were successful to some extent for the offshore fishermen but not enough to be worth the effort.  At the time of this writing, there are only a few inshore participants still using this equipment.  The individual who sold the units has reduced his support significantly and, in fact, only maintains the business on the side.  The effort of logging mooring locations hashowever been reduced over the years as fishermen come to understand the notion of "fixed sites", In other words, after the position and depth of a particular site are accurately recorded, it becomes easier for the fishermen to simply redeploy the instrumentation at those sites. Much of the burden in documenting deployments falls on the lobster association representatives.While we attempted to disperse some of these task to a set of ?industry reps?, the added layer in the organization only added more confusion.In subsequent phase IV therefore, we scaled back to a single layer of ?association reps?.  It is now their task to transfer the handwritten logs to electronic spreadsheet files in specific formats.  Much of the eMOLT funding goes to their time on this effort as well as the equipment needed to do so (laptops, printers, etc).  The difficulty of converting between units used by fishermen  (Farenheight, fathoms, Loran TDs) to those expected by the scientific community (Celsius, meters, lat/lon) and then back is not insignificant. 

Phase IV Drifters ( Subcontract #04-817)

As we enter our 4th year, we are preparing for a new exciting phase of the eMOLT project. While they will continue to maintain the temperature records,   lobstermen will also be deploying a set of at least 16 drifters each month  of the summer of 2004.  Drifters are constructed by marine science students at the Southern Maine Community College.  Approximately a quarter of these drifters will be tracked by satellite  while the others will rely on mariners phoned-in sightings.  A  toll free system has been set up for individuals to keypad ID#s and positions. The data will be automatically entered into an ORACLE table throughan Interactive Voice Response system maintained byNMFS in Gloucester..   All drifters will be tracked on the emolt.org site and paths will be compared to numerical model simulations. 

To date, association reps have identified lobstermen to participate in this project and scheduled a drifter training session as part of the Maine Fishermens Forum.Students from SMCC have constructed the majority of the drifters and are working on integrating a terrestrial gps device into the drifters as a low cost tracking device.Association representatives are charged with a major outreach effort this Spring.  They are funded to attend dozens of  meetings and distribute information to all mariners in the Gulf of Maine about the protocol to follow on sighting one of these units.  As part of phase IV funding,  LCD projectors have been purchased for each association so that, given the laptop and software purchased in earlier phases, they are now equipped to make PowerPoint presentations at these various meetings. 

For further information contact: James.Manning@noaa.gov

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