Guest Contribution by Dr. Stephanie Boudreau, Dalhousie University
Upon entering the airport in Portland, Maine, the first thing I saw was a sign with a lobster welcoming me “home”. Immediately I knew I had come to the right place. From November 27th to 30th, 2012, Portland was home to Canadian and American lobster scientists attending “The American lobster in a changing ecosystem” symposium. I had read the abstracts on the plane and was one excited lobster scientist! With a changing ocean and coastal communities becoming increasingly dependent on lobster fisheries, the symposium aimed to summarize the state of lobster science, identify relevant research gaps, and foster cross-border collaborations.
The American lobster (Homarus americanus) is native to the northwest Atlantic Ocean and has a huge home range. They’re found in the cold northern waters of Newfoundland and Labrador down to the warm southern waters of North Carolina. Lobster populations in the Gulf of Maine, the centre of their distribution, seem to be experiencing ideal conditions and living the decapod dream. Catches and abundance of lobster in the Gulf of Maine (and northward) have increased for both the USA and Canada since the 1980s, reaching historically high levels which have coincided with a decline in large groundfish abundance, such as the Atlantic cod (Gadus morhua). In contrast, the populations in southern New England have reached critical lows due to disease and large-scale mortalities.
On the symposium’s first morning, Robert Steneck set the stage for the Gulf of Maine ecosystem and fishery, noting that lobster is the only fishery that has been targeted for 150 years and is now doing better than ever. Steneck attributed this abundance to being released from groundfish predation, being long-lived, large and armoured with a hard shell, and to producing many offspring. In his provocative (to me) opinion, humans have essentially domesticated and cultivated the Gulf of Maine lobster boom- by removing top predators and feeding the system with bait from lobster traps.
On the second day, Michael Fogarty showed how the Gulf of Maine lobster population has shifted two degrees in latitude since the 1960s, moving North and East, and expanding onto non-traditional sand and mud habitats which offer little protection from predators. Until the 1990s, temperature and lobster landings were linked, with landings being predicted by the temperature about 6 years earlier. Today however, this relationship has changed.
I built my PhD thesis around the findings, questions, and ongoing work of scientists like Steneck and Fogarty. My research explored trends in lobster abundance on a larger scale by looking for relationships between lobster, their predators, and temperature from pre-existing datasets. This means that over past few years I have spent a lot of time looking at numbers but have rarely held a live lobster in my hands. What was really exciting was learning about all the research being conducted by people who directly interact and observe lobsters. There was an amazing breadth of knowledge (and plenty of lobster rolls).
Some more highlights:
- Jeffrey Shields discussed environmental stressors influencing lobster health, like temperature or contaminants. Shields also noted approximately 50% of the lobster in Long Island Sound, CT, are blind, but because lobster gather most of their information from chemical cues, as we’ve learned from Jelle Atema‘s work, what this means for their survival is unknown.
- Marissa McMahan showed that lobster can likely detect the presence of cod and then change their behaviour by moving smaller distances.
- Ann-Lisbeth Agnalt, has been observing the growth and behaviour of hybrid lobsters from an American lobster (named Amanda) found in Norwegian waters carrying eggs fertilized by a European lobster (Homarus gammarus).
- Derek Perry presented evidence of smooth dogfish (Mustelus canis) predation on lobster in Buzzard Bay, MA, in the fall. His poster was complete with awesome photos of a non-lethal stomach sampling technique; pumping water into the shark’s gut so that it would barf its stomach contents.
- Noah Oppenheim showed video of the very first evidence of night-time cannibalism of small lobster by larger ones.
- Ryan Stanley opened his talk with a photo of four sibling lobster larvae, each a different colour.
- Building on Rick Wahle‘s lobster settlement index, Rémy Rochette and his students Kristin Dinning and Guðjón Már Sigurðsson showed that while cobble is still the most important habitat for juvenile lobster, small lobsters are being found more often on non-traditional bottom-types (mud and sand).
- From a commercial fishery angle, Anna Henry presented her research assessing the vulnerability and social resilience of fishermen who have become increasingly dependent on one species- lobster- for their livelihoods. Henry’s human ecology perspective provided valuable, context and insight into how communities cope and adapt to threats such as drops in lobster prices and changing environmental conditions.
It’s no surprise that the conference captured media attention, though there were plenty of self-deprecating comments, delivered with a wink, about it being a slow news week in Maine. Lobster is extremely important to New England and Atlantic Canada and we are reliant upon one another for processing and trade. Personally, I would prefer if the media used a more elegant and positive word than “glut” to describe the super-abundance of lobster, but from a socio-economic perspective there are very real issues with the high catches, beginning with the low price at the wharf for both Canadian and American fleets. This summer, the low prices became personal when New Brunswick fishermen protested the import of “cheap” Maine lobsters by their local processing plant as opposed to buying their locally landed catch. This was not unnoticed by politicians, and was mentioned by Aaron Annable, Consulate General of Canada, during the symposium’s welcoming remarks.
It is amazing that despite the wealth of lobster research and knowledge we’re still asking, Why are there so many lobsters in the Gulf of Maine? How long will the boom continue? And what will be the trigger that changes the game? The reality is that it is that there are likely many things (less predators, ideal environmental conditions north of southern New England) bolstering lobster populations. Keeping in mind that lobster supports commercial fisheries and coastal communities, there is a sense of urgency among many of us to address some of these larger questions, but after spending an inspiring couple of days with representatives from industry, government, non-governmental organizations, and academia, I’m confident that the lobsters are in good hands.
Boudreau recently completed her Doctoral research with Boris Worm and is a new post-doctoral fellow in Dalhousie’s Marine Affairs Program.