In This Edition - Winter 2004

• Canadian/U.S. Lobstermen's Town Meeting Scheduled for April 23 
  
  
• "Spotlight" -- Early Shell Disease Research
  
  
• Lobster Institute Web Site to See Technology Upgrade
  
  
• Lobster Art Sought for Juried Show
  
  
• Research Report
  
  
• Choose Another Bulletin

Canadian/U.S. Lobstermen's Town Meeting Scheduled for April 23

     A Canadian/U.S. Lobstermen’s Town Meeting will be held in Portland, Maine on April 23 from 10:00 a.m. – 4:00 p.m. at the Double Tree Hotel.  Hosted by the Lobster Institute, the Lobstermen’s Town Meeting will be an industry-wide gathering of lobstermen and other interested parties, coming together to discuss the status of the lobster resource.  “Lobstermen from all geographic areas of the fishery are encouraged to attend and share what they see, what they know, and what they can tell us about the resource. What impacts the fishery in one area could very well impact the fishery in others, that’s why we’re inviting lobstermen from Canada down through to Long Island Sound to join us,” said Dana Rice, chairman of the event’s planning committee. “A unique feature of this meeting is that it is structured with an emphasis on the lobstermen’s perspective,” said Rice.  “Rather than fishermen listening to scientists, scientists will be invited to listen to the fishermen.”

     The primary goal of the Lobstermen’s Town Meeting is to provide fishermen with an opportunity to share with one another what they are observing in their day-to-day operations in their region, what their concerns might be, what positive things they are seeing, and how resource managers and scientists might use the information they can provide.  In addition it will allow fishermen to get a more complete picture over the range of the entire resource, including commonalities, differences and potential future impacts.

     “This is an opportunity for lobstermen to help set the agenda for needed research for the fishery on an industry-wide basis, research geared toward both preservation and the responsible use of the resource, while maintaining the vitality of the industry,” said Dr. Robert Bayer, executive director of the Lobster Institute.  “We are fostering collaboration and communication between all geographic areas of the fishery to reinforce the fact that all share and rely on a common resource that must be protected.” 

     According to Bayer, the morning session will be devoted to a true “town meeting” style discussion, directed by a trained moderator provided by Maine Sea Grant. Active participation in this component of the meeting will be limited to industry people (fishermen, dealers, pound owners, processors).  The focus of the discussion will be on the status of the resource and its habitat.  Scientist and regulators will be invited to listen to the discussion. During the afternoon there will be a “Meet the Scientists” session.  This part of the event will be set up in a “trade show” format, with each participating scientist having a booth where they will set up information relevant to their research. This will be followed by “round table” discussions on areas determined to be of most interest during the morning session.  Key researchers will be available to provide input and share the current status of studies being done.

    The morning session will be recorded, and tapes or transcripts will be made available to interested parties.  In addition, a summary report of the Town Meeting and the breakout discussions will be compiled and sent directly to appropriate research universities/organizations, regulatory groups, granting agencies and foundations. It will also be available upon request to any interested parties and will be posted on the Lobster Institute’s Web site.   

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Early Shell Disease Research

     Did you know that the Lobster Institute has been involved with shell disease research for over fifteen years?  Up until five or six years ago shell disease in free-living lobsters had occurred at what can be considered insignificant levels, yet the disease has been seen in lobsters stored in tidal lobster pounds for decades.  Shell disease in the American lobster was first documented by Hess in 1937 in lobsters removed from a tidal storage pound in Nova Scotia. Indeed, shell disease has been a considerable problem in lobster holding facilities for many years with some pound owners experiencing market losses up to 35% in the past.  The incidence of disease in pounds may compounded in part by the lobsters’ susceptibility to infection when stressed.

      Lobster Institute Research Associate Dr. Deana Prince and Institute Executive Director Dr. Robert Bayer began studies on shell disease in impounded lobster in the late 1980s. Scanning electron microscopy (SEM) of lesions of infected lobsters revealed a number of different forms of bacteria, including ones resembling Aerococcus viridans (a bacterium that causes gaffkemia – aka Red Tail Disease).  Additionally, the thin shell in the lesion area appeared to be vulnerable to penetration by the associated organisms. Prince and Bayer conducted further studies on impounded lobsters with shell lesions from a tidal pound in Nova Scotia in the early 1990s. Attempts were made to isolate and identify the microorganisms associated with shell disease, with particular emphasis on the chitinase activity of those isolates. No isolates appeared exclusive to lesions as normal shell yielded similar flora. Additionally, SEM and transmission electron microscopy (TEM) were used to examine the interaction between the associated organisms and the lobster shell.  Diseased shell displayed surface fouling by microorganisms while normal shell did not.  Erosion of the epicuticle, exocuticle and in some cases the endocuticle was evident within the lesions. Loss of these shell layers was coincident with the presence of bacterial mat in the lesions. In attempts to transmit the disease to healthy lobsters, their dorsal carapaces were abraded with sandpaper, followed by the application of a cultured chitinolytic bacterial isolate, or by direct transfer of inocula swabbed from diseased individuals.  Heavy melanization occurred at the sites of abrasion, yet the development of typical lesions was not observed.  Shell erosion typically extended to the exocuticle, however bacterial fouling was not extensive.  In short, the disease could not be transmitted in this manner

     Because defenses of impounded lobster may be affected by inadequate nutrition, the Institute studied the effects of an experimental pelleted feed on the incidence of shell disease in lobster pounds in 1993-94. Shell disease was observed in 7.73% of lobsters fed the pelleted diet and in 10.39% of lobster receiving the traditional diet.  Results suggested improved nutrition might help impounded lobsters resist shell disease.

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Lobster Institute Web Site To See Technology Upgrade

     Want to know where female lobsters carry their eggs? Or check out some good lobster recipes?  One of the best sites on the Web for lobster information is maintained by the Lobster Institute at the University of Maine at www.lobsterinstitute.org. Now grants of $1,000 from the Northeast Farm Credit AgEnhancement Program and $2,500 from Maine Sea Grant will enable the institute to upgrade the site with new technology.

      “Internet users from around the world have tapped into lobster expertise offered by the Institute,” says Cathy Billings, assistant director for communications and development. “There have been millions of hits on the Institute’s Web site since its creation, plus we estimate well over 200 other sites have linked to ours. Those visiting the site include fishermen and others from the lobster industry, scientists, students and teachers at all levels, resource managers, and many others just simply interested in lobsters,” says Billings.

    Resources available via the Institute Web site include:

Ø      Lobster Library - a searchable listing for hundreds of scientific articles dealing with studies on lobsters.

Ø      Lobster Bulletin - an archive of this quarterly publication edited by the Institute

Ø      Lobster Experts - a resource of lobster researchers, with contact information and areas of expertise

Ø      Lobster Biology - biological information and diagrams, and links to other informative sites

Ø      Lobster Quiz – fun, educational lobster questions

Ø      Lobster Cam - video feed from a real lobster trap

Ø      Lobster Boat Video - a trip out on a lobster boat

Ø      Lobster Links - a portal to all things lobster

     As upgrading of the Lobster Institute’s Web site gets underway, the site can still be accessed online at www.lobsterinstiute.org, but several of its features are temporarily out of service. The Institute would like to raise an additional $10,000 to complete the modernization/enhancement process.  Those interested in more information about ways to contribute to this project can contact Billings at 207-581-2751.               z

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Lobster Art Sought for Juried Show

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 ResearchReport

Readers may contact the Lobster Institute for more detailed information on any of the projects reported.    

v     Lobster Institute’s Analysis Re-affirms Quality of Lobster Meat – The Lobster Institute is regularly asked to conduct tests on various factors related to the quality of lobster meat.  They were recently called upon to re-affirm that the American lobster has safe levels of lead – well below the minimum acceptable levels set by the U.S. Food and Drug Administration (USFDA). The Institute worked with Dr. John Cangelosi of the University of Maine’s Environmental Chemistry Lab on the testing.  Lobsters were supplied by six Massachusetts lobstermen from various locations, and funding for the lab work was provided by the Massachusetts Lobstermen’s Association. The Institute confirmed that the USFDA lists a lead level of 1.5 ppm as a guideline for acceptable levels for crustaceans.  According to Cangelosi, the lead detection limit for lobster tail meat is 0.10 mg/kg or 0.1 parts per million (ppm), and lab test results showed that “the samples…are below our detection limits for lead”.  

The USFDA’s “Fish and Fisheries Products Hazards and Controls Guidance-3^rd Edition” can be viewed at http://www.cfsan.fda.gov/~comm/haccp4.html.

v     Shell-Diseased Lobsters Show Evidence of Involvement of a Pseudoalteromonas Species of Bacteria –In November of 2003, the Lobster Institute worked with Dr. Katherine Boettcher and Research Assistant Aaron Maloy from the University of Maine(Dept. of Biochemistry, Microbiology and Molecular Biology) on an analysis of  shell-diseased lobsters originating from the Connecticut side of Long Island Sound.

Two different groups of affected lobsters were tested, and in each case, the total number of bacteria recovered from lesions was approximately 10-fold higher than the number recovered from an outwardly healthy portion of carapace. Additionally, one specific type of colony was numerically dominant in the samples from lesions. On the surface of an agar plate, the colonies are distinct in their pink pigmentation and copious production of extracellular polysaccharide. Initial characterization of isolates revealed that they are gram-negative rods, oxidase positive, and with weak catalase activity. Further, analyses of the 16S rRNA gene showed those sequences to be 100% identical among isolates. These data were used to place the organism in the genus Pseudoalteromonas. Although it could not be assigned to any known species, the strain  (designated LSL) shares >99% sequence identity with an unidentified Pseudoalteromonas isolate from squid nidamental glands. Researchers at Woods Hole, MA previously isolated members of the genus Pseudoalteromonas, which they believe may be involved in shell disease of lobsters from Long Island Sound and the coast of Massachusetts (Roxanna Smolowits, personal communication). The relationship of those strain(s) to LSL is not yet known. 

Based on what is known of other Pseudoalteromonas species, it is reasonable to expect that strain LSL may play a primary role in lobster shell disease. First, it is a general feature of Pseudoalteromonas strains to associate with macrofaunal hosts.  Pseudoalteromonas strains have been isolated from sponges, mussels, fish species, tunicates, and even algae.  In one case a Pseudoalteromonas spp. (P. bacteriolytica) was directly implicated as the causative agent of Red Spot Disease that affects Laminaria japonica. Pseudoalteromonas species are also suspected agents of shell disease in the crab Cancer pagarus, and spiny lobsters (Panulirus argus) off the Florida Keys. Second, Pseudoalteromonas strains are known to produce a wide range of biologically active extracellular metabolites such as anti-bacterial, anti-fungal, anti-viral, agarolytic and bacteriolytic compounds.  Biologically active compounds such as chitinase, produced by Pseudoalteromonas strain S91 and trypsin-like proteases produced by P. haloplanktis strain S 5B are of particular relevance to investigations of shell disease. This is because most cases of shell disease in crustaceans are caused by the enzymatic deterioration of the calcified cuticular layers (composed of chitin and protein) of the integument. 

    (Excerpt from an unpublished report by Boettcher and Maloy.  Portions of this report and references sited were omitted due to space considerations.  The full report with information on protocols used and references sited is available through the Lobster Institute)   z 

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