Monitors on Lobster Traps
I Temperature (Completed in 2002)
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.
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.
II Salinity (Subcontract #02-579)
report for the salinity phase is in preparation and due 15
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.
final report for this phase is in preparation and due 15
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.
IV Drifters (
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
All drifters will be tracked on the emolt.org site and paths will be compared
to numerical model simulations.
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
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.