Charting a Course for Gulf of Maine Cod: Part II

Atlantic cod

Atlantic Cod; Photo Credit: NOAA

Yesterday, I recounted the recent history of assessments of the Gulf of Maine (GOM) cod stock that has led to a looming crisis for many New England fishermen, and the management response underway in the form of emergency action.  Today, I discuss two major goals that will most effectively use the time before us to potentially change our understanding of cod status, and avoid or minimize socio-economic hardship.

Expand our scientific perspective
Before the 2011 assessment had even been reviewed, a barrage of criticisms began to be levied.  To be sure, many decisions made during the assessment could have gone a different direction, including data to include or exclude, values for key parameters, and determination of reference points.  Renowned ecologist E.O. Wilson once observed that ecology is far more complex than physics, and fisheries science is a close cousin of ecology.  There are few universal rules for how to assess fish stocks, and the discipline relies heavily on experience, professional judgment, vigorous debate, peer review, and trial and error.  The GOM cod assessment was not lacking in any of those elements.  In my view, the assessment was done right, was done well, and should be commended for achieving what it set out to do.  Gerrymandering the assessment to get a more favorable outcome is both bad practice and bad policy.

However, the ecological processes, and therefore the data, considered in a stock assessment represent a surprisingly small amount of what we know about marine ecosystems, the enormity and complexity of many assessments notwithstanding.  Stock assessments more often than not ignore spatial patterns in distribution, growth, mortality, reproduction, recruitment and movement across the stock area, and even more rarely consider interactions with other species and effects of benthic habitat, oceanography and climate.  In many cases, those simplifications are necessary for practical reasons, and tolerable.  But when the consequences of an assessment are so severe, it is entirely appropriate, and indeed responsible, to delve deeper into the scientific basis for management to make sure that our simplifications are not giving us a picture that is too far off base.

So what are the new questions we should ask that the assessment was not designed to address?  The first is whether the stock units are defined appropriately.  Most assessments assume the population is relatively closed, with negligible emigration to or immigration from other areas.  Currently, the GOM cod stock unit ends at the tip of Cape Cod and the northern edge of George’s Bank.  However, there is evidence that cod in the western GOM are genetically linked to fish off southern New England, and that perhaps those areas should be linked via waters west of the Great South Channel.

Additionally, there is a stark contrast in abundance of cod between the eastern and western Gulf of Maine.  In fact, I see this pronounced spatial disparity as being the fundamental root of the dispute between fishermen and scientists.  Most fishermen reliant upon GOM cod operate from Port Clyde, Maine to the tip of Cape Cod, an area in which NOAA survey data show cod to be fairly abundant.  When fishermen head to sea, they directly encounter that abundance.  However, survey data also show that further east, cod are much scarcer.  The assessment covers the entire GOM, so abundance in the west is offset by scarcity in the east.  The result, not surprisingly, is a picture of lower overall abundance than fishermen directly experience.

The question, then, is why there is such a stark difference, and what are its implications?  If cod dynamics on either side of the GOM are too different to be captured by a single model, separate models for the eastern and western GOM might be needed.  In fact, tagging studies suggest the eastern GOM might be more closely linked to Canada’s Scotian Shelf and eastern George’s Bank. Those linkages might need to be captured.  Or, movement of adult and larval cod across the eastern and western GOM might warrant considering both within a single model that explicitly accounts for the unique status and dynamics of each sub-stock.

As we better understand spatial structure, we should also define its major drivers, including behavioral diversity within and between populations, responses to habitat features, oceanographic effects on larval supply, and interactions with predators, prey and competitors.  Answering those questions can enable construction of more detailed ecosystem-based models, or at least estimating area-specific parameters for single-species models.  Furthermore, we could develop more targeted strategies beyond GOM-wide quotas, such as quotas and other management measures unique to specific locations (some of which are already in place).  Or, if prey availability prevents cod from re-establishing populations in depleted areas, actions to re-build forage fish might be part of the strategy.

NOAA has asked the Gulf of Maine Research Institute to lead an examination of these questions, and EDF will be integrally involved in that effort.  If nothing else, this will allow us to craft more creative and surgical management responses.  Moreover, my hope is that, far more than repeating the assessment and hoping for a new answer, this will give us the best chance of changing our understanding of cod status.

Contingency planning
Unfortunately, it is possible that digging deeper scientifically will not lead to fundamentally different conclusions.  My hope remains that it will.  But, while the scientific work is underway we should not sit idly in the face of an undesirable outcome, to say the least.  Rather, we should be developing contingency plans for the industry if drastic cuts in quota become inevitable.

A common approach to dealing with resource depletion and consequent economic shortfalls in New England has been the use, and arguably abuse, of government relief funds.  That is not to say that this should not be an option, and cannot be an effective one.  How much would be available, who would receive the funds, and how they would be used are critical questions that will determine the effectiveness of this approach.  However, a political climate favoring reduction of both government revenue and spending might render this an unlikely, or at least limited, option, and other ideas will be needed.

A more constructive direction would be to develop strategies for generating more value from other species.  Pollock, redfish, whiting, dogfish and other lower profile species currently fetch comparatively low prices, and the total landings of many are well below catch limits.  It would be worthwhile to figure out how these species can generate more value through a combination of improved handling and quality control, accessing markets in which the species are currently not sold, and perhaps developing new markets, a strategy already reaping benefits in Port Clyde, New Hampshire, Gloucester, Chatham and Point Judith.  In order for that approach to work, it would likely be necessary to improve the catch rates of those species while reducing the catch rates of cod.  That might mean gear modifications, strategically planning the timing and/or location of fishing, and developing communication systems among fishermen that provide early warnings of locations where cod catch rates are higher and should be avoided.

The situation before us is daunting, but not insurmountable.  NOAA has charted a course that finds a balance between reducing fishing pressure, and therefore risk, while minimizing immediate damage to the industry.  In doing so, we have time to better understand the problem, and to craft more creative and effective solutions.  That should mean a combination of more expansive scientific analyses – not a re-hashing of the assessment but rather consideration of ecological processes the assessment was not designed to address – and contingency planning that will allow the industry to endure much lower catch limits should that eventually be required.  Between managers, industry members, and other stakeholders, we have the energy, intellect and experience needed to navigate the waters ahead.  It’s time to get to work.

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