On Nov. 5, the Atlantic States Marine Fisheries Commission’s Northern Shrimp Section met in Portland and, after a scientific presentation, voted unanimously to close the shrimp fishery for another year. The handful of fishermen and processors in the room pleaded for a short season—anything to keep boats on the water.
However, the results of the annual survey and stock assessment showed the second lowest biomass on record (the lowest was in 2013). The scientific Technical Committee left the shrimp section with a strong message: “Long term trends in environmental conditions are not favorable for northern shrimp. This suggests a need to conserve spawners to help compensate for what may continue to be an unfavorable environment.”
Managers had no choice but to keep boats tied up for another season.
Since the moratorium last season, shrimp have been called the “canary in the coal mine for climate change” in New England fisheries. But the canary analogy, which simply tells the miners to get out or die, may be too simple. Rather, the decline in shrimp seems to be akin to Rachel Carson’s cry for action as she explored the causes of declining bird populations in the late 1950s. The loss of shrimp this season isn’t just a warning: it is an opportunity to identify a responsive path forward for fisheries management.
Climate change is the elephant in the room when it comes to fisheries management. The Gulf of Maine is warming faster than 99 percent of the world’s oceans, and warmer waters are making it harder for some species to live here. Maine fishermen have lost shrimp for the second year in a row and new science suggests that the spawning biomass of cod (another cold water species) is at 3 percent of its target. President Obama just took an important step to slow global warming by pledging to reduce our carbon output over the next decade, but in the meantime our waters are going to continue to warm and scientists, managers and fishermen will need to figure out how to adapt. Shrimp is our best opportunity to learn how.
All fisheries are managed, including cod and shrimp, by creating models that incorporate survey data, landings and natural mortality (death by any means other than humans) to determine an “allowable catch” to report to managers. Managers then decide how to ensure that fishermen don’t exceed that allowable catch. Unfortunately, it has become clear over the past five years that these single species models are not accurately capturing the full picture and something new is needed. Expanding to ecosystem-based fishery management could have immense value for all our fisheries.
An ecosystem model would give managers a better picture of how to protect fish stocks and create a more stable fishery for fishing business. For example, when presenting the bad news on Northern Shrimp, the technical committee reported on many ecosystem factors impacting shrimp numbers. Over the past five years, there were more predators in the ocean, plankton (the primary food source for shrimp) was at a historic low, and the water was too warm for shrimp to reproduce. At the same time, management didn’t control effort and more shrimp were caught than science recommended. If an ecosystem based approach had been used, and scientists and managers had done a better job interpreting the interactions between the shrimp population and the environment, perhaps managers could have been more cautious, monitored catch more closely and set catch limits that left more shrimp to help the population survive through this warming trend.
However, not all is lost. The data exist to start working on this type of approach in the shrimp fishery and managers can react quickly to ecosystem changes. For managing shrimp, data are collected annually, which allows scientists to have a better understanding of what is happening currently. If managers and scientists can figure out how to incorporate new data types, like predator abundance, forage, temperature and even ocean acidity into the equation on a yearly basis, this could be the future of fisheries management.
Managers, scientists and fishermen all want the same thing: robust fish stocks and a healthy fishing industry. Instead of reacting to the decline in shrimp and cod as a miner would to a dead canary and getting out as quickly as possible, managers and scientists can take this opportunity to fix a problem and take a step forward in fisheries science and fisheries management.
A more holistic look at fisheries that incorporates the newest and best data in a timely manner and gives managers the knowledge they need to make an educated decision is our path forward. This is what we must strive for in shrimp and for all our fisheries.
It may not be a silent spring, but a shrimpless winter is a pretty terrible future for Maine.
Ben Martens is executive director of the Maine Coast Fishermen’s Association