By Kathleen Reardon and the DMR Lobster Research Team
Kathleen Reardon is DMR's lead lobster biologist. DMR photo.
The DMR Lobster Research team was busy in 2021. Most fishermen have heard of our longest running and largest data collection program, Commercial Sea Sampling, where samplers go on commercial trips to work with the captains and crew on a fishing day. Samplers measure the lobsters in the traps, not for enforcement, but to record the biological composition of the catch including the legals, shorts, V-notches, eggers, and oversize. This program completes three trips in each zone, May through November, and also does limited sampling in the winter to provide trends by zone and month over time for lobster catches, discard rates, V-notch rates, egg development, and shell disease rates. This program depends on the voluntary participation of captains. These data are essential to the ASMFC Lobster Stock Assessments by providing general biological and discard information to inform management models.
In addition to Sea Sampling, the DMR has multiple long-term monitoring programs that track the trends of lobster at different life stages through fishery independent data and feed into the Lobster Stock Assessment. The Settlement Survey is a SCUBA based survey completed in the fall and has been monitoring 40 sites since 2001 looking for the young of year, or new lobster settlers, and juvenile lobsters in cobble habitat coastwide to develop a relative index of settlement density over time.
Another survey, the Ventless Trap Survey, was started in 2006 and annually contracts with nine industry boats through competitive bid to haul the survey traps. This survey uses small mesh traps without escape vents to target juvenile lobsters. The 276 sites, with three traps each, are hauled twice a month during June, July and August. These sites are randomly selected from the three coastal statistical areas and at three depths — 1-11 fathom, 12-21 fathom, and 22-32 fathom.
DMR surveys and sampling programs track lobsters throughout their life cycle. DMR graphic.
The Maine-New Hampshire Trawl Survey is a multispecies survey developed to extend coverage of the federal bottom trawl survey into inshore waters. Data from the survey provide an important relative index of lobsters in the coastal waters out to 12 miles. The survey has been conducted in the spring and fall since 2000. It attempts to complete 120 randomly selected tows each season. With funding awarded from National Sea Grant, the survey started collecting samples this year to evaluate potential predators of juvenile lobsters. This project will continue until 2023 and will provide information for the stock assessment.
Our newest long-term survey, the Boothbay Larval Survey, started in 2017 and targets the larval stages of lobster at the surface with a fine mesh plankton net. The objective of this survey is to collect data on the timing of the larval season and abundance of the four larval stages starting in June and finishing in September or early October. Currently this survey only covers the Boothbay area, but, in 2021, with funding from National Sea Grant and a collaboration with Atlantic Offshore Lobstermen’s Association, New Hampshire Fish & Game, Maine Maritime Academy, and Hood College, we explored the concept of seasonal larval surveys from fishing boats with two transects out to 24 miles from Boothbay and Steuben. We sampled weekly and biweekly through the season as part of the larger project. In addition to this collaboration, DMR also continued research on another project, funded by the National Science Foundation with Hood College, University of New England, and Bigelow Laboratory, exploring the differences between lab raised and wild caught lobster larvae. This work will help us understand how lobster larvae respond to a range of temperatures in the wild.
A three-year study on female lobster has given DMR information on changes in maturity. Photo courtesy Portland Press Herald.
In the culmination of a three-year lobster maturity project to update and determine the size at which 50% of the female lobster population is mature in different areas (an important parameter in stock assessment models), the DMR is evaluating alternative maturity determination methods to make future updates more efficient and less labor intensive in an additional National Sea Grant funded project. This project, building from the recent DMR research, will also develop manuals to assist other scientists looking to replicate this work.
The DMR research team has also been working to provide information on different ways to achieve compliance with the new 1700-lb. breaking strength buoy line weak points, required by the Atlantic Large Whale Take Reduction Plan by May 2022. DMR submitted data to NOAA on different ways to reduce the breaking strength of rope. NOAA will determine which of the methods submitted by DMR are approved for use as weak links. DMR has requested approval for options that include particular diameters of rope and integrated knots but has not received feedback yet.
One option that has been approved by NOAA is a commercially manufactured plastic weak link that will allow for fishermen to retrofit their current gear. A small number of those weak points are available for testing (if interested, email kevin.w.staples@maine.gov) or John Higgins with NOAA Fisheries. The DMR has secured funding through Maine Outdoor Heritage Fund and Section 6 to try to make this option commercially available in early 2022.
The lack of spatial data for the lobster industry in the whale and wind discussions has also accelerated the development of boat tracker technology in 2021. The DMR has tested a number of low-cost options that transmit data through cellular networks rather than over satellite. The DMR is looking for volunteer boat captains to test these units, which are slightly larger than a smartphone, especially in harbors where cellular service is not as strong. You can contact Kevin Staples at DMR if you are interested in participating at kevin.w.staples@maine.gov.
DMR has secured funding from the Maine Community Foundation to collect better data on right whale distribution and habitat use in the Gulf of Maine. This funding has allowed the DMR and the University of Maine to place seven passive acoustic receivers in central Gulf of Maine, up to 75 nautical miles offshore, in addition to the eight inshore receivers deployed in state waters by DMR and NOAA in early 2020. Data from the receivers are retrieved every five months and the units re-deployed. The first offshore data will be downloaded in March 2022.
In 2021, the DMR Landings Program worked with Bluefin Data LLC. to develop a Maine Harvester app (VESL) to allow harvesters to report catch and effort information digitally to prepare for new management requirements in reporting. The app is currently going through the process to be approved by GARFO as an acceptable eVTR program. The app was created with the objective of collecting the necessary information in an intuitive and efficient way. This app is designed to allow harvesters to create a report whether or not they are connected to the Internet and then submit those reports once they have an active internet connection.
This app builds upon the success of the web-based data entry program built into DMR’s Maine LEEDS program that fishermen use to electronically renew their licenses. The DMR is also working on methods that use the aforementioned tracking units to automatically satisfy various harvester reporting requirements and reduce the time fishermen spend on this task.
Thank you to the industry for all the support and collaboration making this research possible. We look forward to sharing the results of our work and continuing the discussion of research questions we should be tackling in the future.