Article Published April 2023
While satellite tags are expensive, they remain one of the principal ways to collect movement data on marine and terrestrial animals independent of direct human contact. The founder of the Dolphinfish Research Program, Don Hammond, deployed the first satellite tag on a dolphinfish for our program on June 4, 2005. During his tenure, he deployed fourteen satellite tags, with the majority released using the traditional harpoon method whereby a tag is inserted into the muscle of the fish with a forceful but controlled jab. Hammond was concerned about the harpoon method being detrimental to the survival of the fish and ultimately leading to lower tag retention. Consequently, he began experimenting with a new method that required more time with and care of the fish. He coined the new technique the “thread-through” method in which the tag was essentially buttoned to the fish. Results from his first five attempts from 2006 through 2008 using the thread-through method, however, did not reveal any differences in survival or retention time on the fish versus the harpoon method. Then, in 2011, we successfully implemented the thread-through method aboard Missing Angel on a 43″ bull but introduced in-water recovery for the fish and the bull carried the
at large, there are a multiude of events that could result in little to no data being collected at all which include, but are not limited to, tag failure, destruction through predation, or damage to the antennae, etc. Finally, acquiring enough data after overcoming the aformentioned challenges to advance our knowledge of this species through science takes years of work. Remarkably, over the past fifteen years, our major corporate and fishing club sponsors, private donors, and network of fishing teams have helped the program acquire over 400 days of satellite tracking data from male and female dolphin along the U.S. East Coast, the Bahamas, Caribbean Sea, and Eastern Tropical Pacific Ocean.Each component presents challenges. First, while the costs of certain models of PSATs have lowered over the years, the most sophisticated tags capable of gathering the greatest amount of data still cost $5,000 each. Second, recruiting a captain and their fishing team to help offset outing costs along with giving up a trophy dolphin if caught for science also presents challenges.
s, our major corporate and fishing club sponsors, private donors, and network of fishing teams have helped the program acquire over 400 days of satellite tracking data from male and female dolphin along the U.S. East Coast, the Bahamas, Caribbean Sea, and Eastern Tropical Pacific Ocean. These data have already been published in five scientific journals and used to describe the overall daily vertical movement strategy and habitat use of adult male dolphinfish, migration routes and pathways among jurisdictions throughout the western central Atlantic Ocean, differences in movement patterns observed from conventional tagging data, gender specific habitat use and movement differences, behavior near fish aggregating devices (FADs), and more.Through the years, the DRP’s tagging technique also evolved from in-water harpon tagging to an on-board thread-through method developed by Don Hammond.
While the DRP has not published a scientific paper on the difference between tagging techniques, observed data indicate more data is acquired and tags achieve their programmed interval more frequently using the new method. By using this technique in combination with a tagging cradle developed in 2018, our goal is to acquire 200 days of satellite tracking data over the next 12 months working with multiple fishing teams in the Caribbean Sea, Mid-Atlantic Bight, and Eastern Tropical Pacific Ocean. Gathering these data will allow us to better understand the movements and habitat use of this species in areas that completely lack these data yet fishing pressure on the species is high and abundance appears to be lower than in the past. Help us fund the acquisition of detailed data records on this vital fish species. There is no donation too small to help us acquire 200 days of data in the next 12 months. Donate to our satellite tracking program today.