2015 2015: UMass Dartmouth researchers developing open source system for assessing fish movement

Geolocation methodologies could prove essential for fisheries management and catchability of Atlantic cod, yellowtail flounder, and monkfish

UMass Dartmouth School for Marine Science & Technology (SMAST) Associate Professor Geoffrey Cowles is leading a collaborative research effort to develop geolocation methodologies to improve understanding of fish movement patterns of Atlantic cod, yellowtail flounder, and monkfish. The project will focus on the Gulf of Maine/Georges Bank and includes researchers from SMAST, Northeastern University, the Gulf of Maine Research Institute, the Massachusetts Division of Marine Fisheries, along with the fishing industry.

Geolocation, which is the process of taking data recovered from a fish archival tag and coming up with the best estimate of positions between release and recapture, can provide insights into catchability and fishery interactions. Using this technique, the research team will be able to guide behavior-dependent aspects of the model parameterization, as well as interpret the geolocated tracks. Researchers will also employ their collective skills in computer programming, oceanographic modeling, statistical analysis, and fisheries biology to assist in furthering the development of technology to geolocate fish.  

This study will also use data acquired from previous studies on each of the example species, which all have their own characteristic behaviors and were tagged in different areas of the Gulf of Maine and Georges Bank region. Most studies of fish movements have relied on fishery recaptures of conventional tags, which provide only the locations of release and recapture. Such tagging studies may bias perceptions of movement patterns. 

Archival tags, which are attached to fish internally or externally to record temperature and pressure at regular intervals, enable estimations of fish location while at large. This type of information is often not fully utilized due to the technical difficulties of producing such movement histories via geolocation techniques.

An improved understanding of fish movement patterns is critical for developing sustainable fishery management practices, while also improving the cost-effectiveness and capacity for observations. Furthermore, improving upon current processes increases the ability to obtain objective data on fish distribution for seasons and locations where existing research surveys may not operate.

“By providing valuable information on fish movements, this project could support improved stock assessments by providing greater insights into our understanding of the modeled populations. These include evidence of partial migration, quantifying movement across stock boundaries, and discernment of population structure on a finer spatial scale than the management unit,” Professor Cowles said. “The greater insights into fish movement patterns that geolocation methods can provide will permit investigations into the biological relevance of stock boundaries, given that prevalent movement across management unit boundaries would violate the underlying assumptions of many stock assessment models.”

The resulting geolocation methodology will be made available to other scientists by public distribution of an open source, web-based tool, thereby improving collaboration between fisheries researchers from a variety of research institutes and continuing to advance the field of geolocation.

The project is funded through the NOAA Fisheries 2014-2015 Saltonstall-Kennedy (SK) Grant Program and proposes to address the Saltonstall-Kennedy Grant Program Theme #2: Improve the cost-effectiveness and capacity for observations, which emphasizes the accuracy, timeliness, and availability of methods for the collection, analysis, and reporting of fishery-independent movement data.

The focus at SMAST is on interdisciplinary basic-to-applied marine sciences and the development of related innovative technologies. In addition to the scholarly marine science and technology communities, the SMAST mission also emphasizes interaction with regional industry, and government and non-governmental agencies on compelling regional marine-related issues and technological development.