Lobster Trap Video

What is LTV (lobster trap video)?

LTV consists of a traditional two parlor lobster trap equipped with a time-lapse video recording system (see figures below). We are able to obtain 24-48 continuous hours of video during each soak, depending on whether we use lights and videotape at night. We can then take this data and analyze the movements and interactions of the lobsters around the trap. LTV was first developed as part of a UNH Ocean Projects course, and then Sea Grant funds were used to improve it. Over the years a large number of graduate and undergraduate students have been involved in this project. If you would like a short video about this project, send us $5 to cover the cost of copying of the tape and postage.  

LTV ready to launch. Note the one parlor contains a watertight box with the time-lapse VCR and batteries. The small waterproof camera is located on the tripod. Red lights are added if night observations are neccesary.

LTV on bottom with lobster entering.




Based on our observations of approximately 24 videos obtained during the summers of 1998-2000, we have drawn a number of interesting conclusions, a few of which are listed below. These were presented at the 2000 International Lobster Conference.

1. A large number of lobsters approach and enter traps, yet typically we only catch 1-3 because the vast majority escape. We estimate that 10% of the lobsters that approach a trap enter, and of the ones that enter, only 6% are caught. Over 75% of the lobsters that escape the trap do so through the entrance. The following video shows a lobster escaping through the entrance to the kitchen.



Video of lobster escaping from kitchen

2. Lobsters are very active around traps during the day, as well as the night.


3. Agonistic encounters around traps appear to limit entry and stimulate exits. The following video shows a large lobster chasing away smaller lobsters and then entering the trap. Small lobsters are very hesitant to enter, while larger lobsters tend to move right in like the one shown in this video.



Video of larger lobster chasing away smaller lobsters entering the trap and chasing a smaller lobster out of the trap

4. Once in the trap, lobsters tend to "defend" the resource. The following quicktime video demonstrates this behavior.


Video of a lobster in the kitchen preventing others from entering

Current Projects

Currently, we are developing a computer model of a lobster trap, using the data we have collected with LTV. We are also comparing data collected with LTV and traditional traps, with diver surveys. Our goal is to develop a more accurate way to easily and accurately assess the actual abundance of lobsters on the ocean floor. These studies are being carried out at our Wallis Sands study site and adjacent rocky habitats (see the following sections for details of this site).


Wallis Sands Study Site

We have focused our studies with LTV at the Wallis Sands study site because it is dominated by a sandy substrate which makes it very easy to obtain accurate estimates of lobster density with SCUBA (see pictures below). In addition, there is a seasonal fluctuation in the density of lobsters so that we can obtain catch and LTV data over a range of densities.

View of Wallis Sands State Beach, from the LTV study site.

Two divers (Win and Jen) conducting lobster SCUBA survey along a 100M transect.

Lobster, easily observed on sandy substrate at Wallis Sands study site.