Defense Date


Document Type


Degree Type

Master of Science

Degree Name

Marine Science

First Advisor

David Kerstetter, Ph.D.

Second Advisor

Rosanna Milligan, Ph.D.

Third Advisor

Thomas Pitchford


Drifting Fish Aggregating Devices (dFADs) are a gear accessory utilized on a global scale by commercial fishers to increase catch size and efficiency of target pelagic fishes such as tuna and dolphinfish. Despite their widespread use, there are few scientific estimates of the total number of abandoned or beached dFADs in the Atlantic Ocean and Caribbean Basin or the compliance of dFAD use with t-RFMO recommendations. Previous studies have utilized the modeled drift trajectories of dFADs to predict beaching probability and location, but this study is the first of its kind, analyzing true beaching events. This study identifies the beaching location, composition, and ICCAT Rec. 19-02 compliance of stranded dFADs in the western North Atlantic and Caribbean Sea using citizen science data reported over social media. Abandoned, lost, or otherwise discarded (ALDFG) dFADs were reported on the shores of the Gulf of Mexico, along the Atlantic coast of the United States and 17 Caribbean island nations, with reports as distant as Scotland, Ireland, and Brazil. Sixty-one (22.8%) dFADs were reported as having beached in United States National or State Parks, MPAs (both domestic and foreign), as well as foreign conservation areas. Furthermore, a total of 119 (61.03%) of photo-documented dFADs were non-compliant. It is my recommendation that the distribution of abandoned lost, and otherwise discarded dFADs be surveyed in the North Atlantic Ocean to gain better understanding of the scope of dispersal and construction. Additional research is necessary to determine best practices of identification marking schemes and ALDFG recovery incentives.