Calibrating Lobster Ventless Trap and Standard Trap Surveys to Optimize Measurements of Lobster Abundance
|Tracy Pugh||UNH - Department of Biological Sciences|
|Abigail Clark||UNH - Department of Biological Sciences|
|Elizabeth Dubofsky||UNH - Department of Biological Sciences|
|Alysia Campbell||UNH - Department of Biological Sciences|
|Kyle Jenks||UNH - Department of Biological Sciences|
|Jason Goldstein||UNH - Department of Biological Sciences|
|Tom Langley||UNH - Department of Biological Sciences|
|Ben Marcek||UNH - Department of Biological Sciences|
|Kate Masury||College of the Holy Cross|
|Audra Chaput||UNH - Department of Biological Sciences|
|Liz Morrissey||UNH - Department of Biological Sciences|
|Chris Chambers||UNH - Department of Biological Sciences|
|Elsa Lindgren||UNH - Department of Biological Sciences|
Underwater video footage from N.H. Sea Grant research incorporated into new lobster exhibit
NHSG-funded research focused on calibrating two types of lobster traps to more accurately determine lobster abundance based on catch. These traps were fitted with underwater video cameras to assist in the data collection process. The video footage taken during this research was incorporated into a new lobster fishery exhibit at the Maine Maritime Museum in 2014. The exhibit educates professionals in the fisheries field about the latest lobster research in New England and helps scientists who conduct ventless trap surveys to assess the accuracy of their data.
Lobster bait deterioration reduces catch after one day in N.H. study
Previous research has shown that ventless lobster traps provide a more accurate estimate of natural lobster populations than standard traps. However, trap saturation may impact these catch values. In 2013, N.H. Sea Grant-funded researchers conducted studies to determine if ventless lobster traps saturate because they capture all the lobsters in the area fished by the trap, the bait in the trap loses its attractiveness, or once a certain number of lobsters are in the trap aggressive interactions lead to an increased rate of escape. Their findings indicate traps do not capture all the lobsters in the area. Rather, a combination of bait deterioration and increased escapes after 24 hours were primarily responsible for reduced catch after the first day the trap is on the bottom. These data indicate that ventless traps may be a useful tool for estimating the abundance of natural lobster populations, especially if steps are taken to adjust for the factors that lead to trap saturation.
Video documenting N.H. lobster research is finalist in Ocean 180 competition
With funding provided by N.H. Sea Grant, researchers conducted studies to determine if the new ventless lobster traps provide a more accurate estimate of natural lobster populations than standard traps. In 2013, the researchers recorded, edited and produced a short video about this research called: What do lobster traps tell us about the lobsters on the bottom? They entered the video into the Ocean 180 Video Challenge, a competition designed to inspire scientists to communicate the meaning and significance of their scientific research to non-scientists. Their video was a finalist in the competition. In addition to gaining national exposure for this topic, the video provides an outreach component to help the layperson understand the importance of natural resource research.
Connection between N.H. Sea Grant research and natural resource organization encourages coordinated lobster management
N.H. Sea Grant-funded researchers conducted studies to determine if new ventless lobster traps provide a more accurate estimate of natural lobster populations than the standard commercial traps. This research is valuable to resource managers who rely on accurate data to help conserve the lobster populations while ensuring a healthy commercial fishery. One of the students who worked on this project was also in charge of the ventless trap surveys conducted by the Massachusetts Division of Marine Fisheries in 2013. This connection provides a direct line of communication between researchers and resource managers, allowing up-to-date research results to be incorporated into lobster management decisions as soon as they are available.
American lobster research in N.H. leads to natural resources employment opportunity
N.H. Sea Grant-funded research focused on the calibration of new ventless lobster traps and standard trap surveys to optimize measurements of lobster abundance. The research supported a number of graduate and undergraduate students, including one Veteran. The experience this student gained from working on this project led to an employment opportunity conducting similar surveys beginning in 2013, with the environmental consulting group Normandeau Associates based in Portsmouth, N.H. This research has directly led to a well-trained professional entering the local workforce and thus contributing to the advancement of lobster and resource management in New England.
Sea Grant Research Helps Refine Lobster Management Tools
The American lobster fishery, valued at close to $400 million annually in New England, is managed based on abundance estimates from standard lobster traps. N.H. Sea Grant has funded research to determine if the new ventless traps that retain more lobsters also provide more accurate estimates of natural lobster populations than the standard traps. Using underwater video cameras, researchers captured footage to determine trap catch per unit effort, time to saturation, lobster density and size for both types of traps deployed in New Hampshire and southern Maine. Researchers determined that ventless traps provide a more accurate estimate of natural lobster populations than standard traps. Abundance estimates may also be influenced by potential sperm limitation in the lobster fishery, so researchers examined the reproductive potential of lobsters in New England. Data indicate that either immature female lobsters occasionally mate, or the size at maturity has shifted towards smaller size classes. Results from these studies will influence the estimates of lobster reproductive biomass in New England waters and potentially the way the fishery is managed.
Available from the National Sea Grant Library (use NHU number to search) or NH Sea Grant
- Jury, S. and W. Watson (2013). Seasonal and sexual differences in the thermal preferences and movements of American lobsters. Canadian Journal of Fisheries and Aquatic Sciences 70(11):1650-1657, November 2013.
- Clark, A., S. Jury, J. Goldstein, T. Langley and W. Watson (2015). A comparison of American lobster size structure and abundance using standard and ventless traps. Fisheries Research 167:243-251, July 2015.
- Watson, W. and S. Jury (2013). The relationship between American lobster catch, entry rate into traps and density. Marine Biology Research 9(1):59-68, 2013.
- Clark, A. (2012). A comparison of standard and ventless American lobster trap dynamics. Master's Thesis, University of New Hampshire.
- Dubofsky, E. (2012). Activity rhythms expressed by juvenile American horseshoe crabs, "Limulus polyphemus." Master's thesis, University of New Hampshire.
- Pugh, T. (2014). The potential for sperm limitation in American lobsters ("Homarus americanus") as indicated by female mating activity and male reproductive capacity. Doctoral dissertation, University of New Hampshire.
- Goldstein, J. (2012). The impact of seasonal movements by ovigerous American lobsters ("Homarus americanus") on egg development and larval release. Doctoral Dissertation, University of New Hampshire.
- What do lobster traps tell us about the lobsters on the bottom? (http://vimeo.com/80803280) (2013) (video)