Successful Longfin Squid Research Track Peer Review

Longfin squid is an economically important species that is challenging to study. Mostly caught from Rhode Island to New Jersey, it supports a commercial fishery worth approximately $32.5 million in 2024. It is often found on restaurant menus as calamari.

Longfin squid live less than a year, grow rapidly, and the number of young entering the population is highly variable. Their populations are influenced by dynamic ocean conditions, leading to shifts in abundance and distribution that are challenging to understand or predict. Longfin squid migrate with the seasons, generally moving south and offshore in the late fall and returning north and inshore during the spring. Scientific surveys capture seasonal snapshots of the population but they cannot provide specifics about the squid caught in the fishery.

Successful Research Track Peer Review

In August 2026, an independent panel of scientists completed the peer review for the Longfin Inshore Squid Research Track Assessment. The panel approved two new assessment models-both of which met all required Terms of Reference and were deemed suitable for management advice. These models mark a significant technical advancement over past index-based approaches. They are better able to capture the rapid growth, seasonal changes in abundance, and unique biology of this short-lived species.

This major accomplishment for a historically data-poor species was possible because of strong collaboration between scientists and commercial fishing industry partners. Having a better foundational understanding of longfin squid life history, as well as two distinct and credible models, gives managers greater flexibility and confidence in using the best available science. The review marks an important milestone in the multi-year effort to improve our understanding of longfin squid and develop better tools to assess the stock.The findings will be implemented during the upcoming Longfin Squid Management Track Assessment this fall.

We combined analytical expertise of scientists with on-the-water knowledge of fishermen who encounter this species throughout the year, making great strides together toward better understanding this economically important and enigmatic species.

"The foundation of trust and collaboration between the science and fishing communities was critical to the scientific progress made during the longfin squid assessment. From sharing ecological observations to collecting data to providing input on model assumptions and outputs, industry partners played a critical role in all phases of the assessment," shared Dr. Anna Mercer, chief of the center's Northeast Cooperative Research branch.

The goals of the collaboration are:

• Better science for sustainable management
• Better information to support decisions about how much seafood can make its way from the ocean to our tables

Industry Collaboration Made the Difference

To support the new assessment models, a working group conducted one of the most comprehensive syntheses of longfin squid life history and population dynamics in the Northwest Atlantic. The working group was composed of scientists from academia, government, and independent organizations, as well as the Mid-Atlantic Fishery Management Council. It met 34 times from 2024-2026, welcoming participation, input, and contributions from the public, including squid industry members.

The Research Track Assessment incorporated several years of data collected by our science center's Cooperative Research Branch in close collaboration with fishermen. Most importantly, cooperative research built the foundation of trust that paved the way for unique collaborations crucial to the success of this assessment.

The Research Track Assessment working group considered and integrated all available data for a more complete picture of the species' population dynamics, including:

"Collaboration with our industry partners yielded invaluable information. In particular, data from processors about longfin squid sizes caught by the commercial fleet were critical," explained Fish Biologist Jessica Blaylock. "Industry perspectives about how well survey and commercial gear catch longfin squid were also instrumental to developing both models."

Squid Squad and the Longfin Squid Summit Laid the Groundwork

For more than a decade, scientists at the Northeast Fisheries Science Center and fishing industry partners have collaborated through the "Squid Squad" to study shortfin squid. This team of federal and academic researchers, fishermen, and managers built relationships grounded in trust and shared understanding to address key scientific and industry challenges. By conducting joint research projects, the group significantly advanced our understanding of shortfin squid biological and seasonal dynamics and environmental drivers. They laid the groundwork for research on longfin squid.

This effort expanded to longfin squid at the Longfin Squid Population and Fishery Ecology Summit held in 2024. At the summit, fishermen and scientists prioritized questions regarding the species that they could address through collaborative research during the assessment cycle. This opened the door for ambitious projects, including the Longfin Squid Biological Sampling Program and obtaining length data from commercially caught squid through four seafood processors. These efforts contributed important information to the Research Track Assessment-one that has historically had fewer biological data available than scientists and managers would like.

Weekly Sampling with Fishermen Provides Critical Information on Longfin Squid Life Cycle

The Longfin Squid Biological Sampling Program was a major source of information for the assessment. The program collected longfin squid from commercial fishing vessels weekly from 2023-2025 and assessed the growth and reproductive dynamics of the species.

"Our partnership with the Mid-Atlantic Fishery Management Council and the fishing industry produced the most comprehensive dataset to date describing the life history of longfin squid, spanning two years of continuous weekly sampling from Cape Cod, Massachusetts, to Cape Hatteras, North Carolina," explained Dr. Mercer. "The partnership of more than 30 fishing vessels and a team of dedicated cooperative research scientists made this possible."

Because squid are difficult to age and study using traditional fisheries research methods, learning about their life cycle has been a challenge. The program provided a comprehensive data stream of lengths, weights, age, and maturity estimates collected using an electronic system. Fishermen provided the critical samples, which were instrumental in informing the stock assessment, and understanding the lifespan, maturity, and growth of longfin squid. By collecting samples regularly throughout the year across a broad geographic area, researchers had a stronger foundation for understanding key biological aspects of longfin squid.

Seafood Processors Helped Characterize the Sizes of Longfin Squid in the Fishery

One of the keys to advancing the assessment and management of this species was gaining a better understanding of the size composition of longfin squid populations. To do so, we needed high-frequency, region-wide longfin squid size and weight samples from the commercial catch. Seafood processors collect this information as part of their business operations. Using it to supplement existing data could strengthen the assessment. Businesses recognized this opportunity and volunteered to share their data.

Four processing facilities contributed their longfin squid size records, including:

• Lund's Fisheries, Inc.
• Sea Freeze Limited
• Sea Fresh USA Inc.
• The Town Dock/American Seafood Partners

The data spanned multiple years and represented up to half of the annual longfin squid landings in recent years.

"Industry groups were very receptive to sharing their data, which totaled more than 1.5 million individual longfin squid lengths, for the stock assessment. Standardizing the various data streams into a consistent format was a laborious task, but our industry partners were engaged from start to finish. They are committed to supporting this assessment into the future," explained Dr. James Gartland, a working group member and scientist at the Virginia Institute of Marine Science.

Assembling the processors' longfin squid size data was time intensive. Working group members and processors are already strategizing on how to make data collection and sharing easier to help with future assessments.

Building on an initiative originally developed for shortfin squid, we have started working closely with the four longfin squid processing facilities on a project that became known as the Squid Size Monitoring program. Our researchers and industry partners co-developed an electronic system to collect standardized squid size and weight data, digitizing what started as a time-consuming manual process. While still in development for longfin squid, the goal is to seamlessly transfer data from squid processors to scientists to efficiently support stock assessments.

"Providing useful data to the science center can bring about mutual benefits for everyone involved. Our commitment to sustainable fishing is the cornerstone of our business plan, and we can't achieve this without our partnership with the dedicated science center staff," said Wayne Reichle, President of Lund's Fisheries, Inc.

Katie Almeida shared, "American Seafood Partners is thankful for everyone who worked hard on the Longfin Squid Research Track Assessment. The Cooperative Research Branch scientists put in the time and effort to gather much-needed information on longfin to help improve the assessment. We are happy to provide samples and data needed to further squid research and look forward to continuing to work together."

Two New Models Provide Technical Advancement and Management Flexibility

Both models credibly represent the stock dynamics and are suitable for providing management advice. The two different approaches produced broadly consistent conclusions: low fishing mortality and high longfin squid biomass in recent years.

These different but complementary assessment models represent major scientific progress. Having two available assessment approaches provides flexibility and allows scientists to evaluate uncertainty.

Complex Model

The State-Space Length Structured Assessment Model reflects our current understanding of longfin squid biology most closely. It produces management advice by tracking the squid population by length and sex and accounting for temperature-dependent growth, the squid's short life-span, and monthly population changes. While it is detailed and sophisticated, it requires more time, data, and resources to update.

Simpler Model

The Seasonal Production Assessment Model produces management advice using an approach that tracks the overall biomass of the stock and incorporates key species characteristics more generally. It captures seasonal population shifts across 6-month intervals while remaining relatively efficient to update.

Stock Assessment: From Research Track to Management Track (and Beyond)

The Northeast Region Coordinating Council uses two distinct processes to manage fisheries stock assessments: Research Track Assessments and Management Track Assessments. The Research Track Assessment path allows scientists to take a deeper look at a stock, develop new approaches, and evaluate different methods before those methods are implemented during the management process. A Management Track Assessment then provides a routine update using the best available information for fishery management decisions, such as setting annual catch limits.

The Mid-Atlantic Fishery Management Council will review the Management Track Assessment results at its December 2026 meeting. It will use the scientific advice to establish longfin squid fishery specifications for 2027-2029. It will incorporate more recent catch data and carry the science developed through the Research Track Assessment into the management process.

The Northeast Region Coordinating Council recommended using the Seasonal Production Assessment Model as the primary basis for developing management advice this fall because of the short turnaround time after the completion of the Research Track Assessment. In the future, either model could be used for Management Track Assessments based on available resources and discussions between the science center and fisheries management partners. In the meantime, scientists will continue to develop the Collaborative Squid Size Monitoring program and refine each approach to best inform future management advice.

Cooperative Research Expands How We Do Fisheries Science

While the successful Longfin Squid Research Track Assessment represents a significant leap forward, there is still much to learn about longfin squid's biology and ecology. Some processes still have yet to be fully understood and will be studied in the coming years to continue to improve scientific advice, including:

• Drivers of recruitment, or the number of young squid entering the population
• Rates of natural mortality and consumption of squid by predators
• Survey catchability and how efficient different gear types are at catching longfin squid
• How to verify squid ages
• Seasonal migration patterns
• Environmental drivers of seasonal population dynamics

This successful peer review is a milestone rather than an endpoint. Scientists will continue working with industry to improve our understanding of longfin squid. The relationships developed with fishermen, cooperative research partners, and seafood processors provide a strong foundation. This is an example of the progress that is possible when scientists and industry members are equal partners in the scientific process. From identifying research needs and collecting samples to sharing observations and fishing methods, industry expertise helped scientists build a clearer picture of the stock.

The longfin squid effort also shows that collaboration does not end when the science is peer reviewed. As new approaches move from research into management, scientists, fishermen, and managers will:

• Continue learning how to evaluate and incorporate new information
• Work through different scientific perspectives and operational constraints
• Translate improved understanding into sustainable management decisions

This assessment also highlights the opportunity to extend collaborative principles throughout the fisheries enterprise and sustain them over time.

Kristan Blackhart, Chief of Population Dynamics, explained, "The Longfin Squid Research Track Assessment expanded our understanding of the species life history, as well as pushed forward the technical basis for assessing this stock substantially. Neither would have been possible without the contributions of our industry partners in the region. It shows what we can achieve when we work together."