In the Fall of 2013, Dr. Zack Jud, a BTT collaborating scientist, traveled to South Andros to lead the first large scale tagging effort on the island. Working together with the guides of Andros South Lodge, the team was able to tag 650 fish over a four day period.
Hoping to continue the success of the 2013 trip, a team consisting of Dr. Aaron Adams (BTT), Justin Lewis (BTT), and Fred Arnett (Bahamas Department of Marine Resources) journeyed to South Andros in January with the hopes of tagging even more bonefish. The team was not only looking to tag fish, but also gather fin clips for genetic analysis as part of the three year Bonefish Genetics Program focused on the genetic makeup of bonefish populations in the Caribbean and Western Atlantic. Determining the genetics of bonefish in the Bahamas is a vital piece of information that will help BTT and fisheries managers in conserving bonefish populations and their habitats in all geographical regions.
This years team was hosted by Bair’s Lodge and used the expertise of the lodge’s local guides to find a lot of fish. Even though the weather wasn’t perfect due to a strong cold front, the team was able to tag and fin clip over 1,000 bonefish. On the first day, due to bad weather, a fast rising tide, and some toothy critters patrolling the flats, over 400 bonefish had to be released from one of the nets before they could be tagged.
One exciting discovery from the trip was a likely pre-spawning aggregation of bonefish; the aggregation consisted of approximately 2,000 bonefish. The fish were observed milling about in a protected deep water bay, exhibiting similar behaviour to fish in other recorded pre-spawning aggregation sites in Abaco, Eleuthera, and Grand Bahama. Between day one and day two the team tagged over 600 fish near the newly discovered pre-spawning aggregation site. One of the fish tagged on the second day at the likely spawning site was recaptured the very next day, 15 miles south of where it was first tagged. Based on our research on Abaco and Grand Bahama, we think this fish likely spawned and then headed home, where we caught it the next day. If so, we’ve already started to connect the likely spawning site to bonefish home ranges, which is exactly the information we need for conservation.
What was odd about the pre-spawning aggregation we observed was its timing. Generally bonefish spawn during the full and new moon phases, but this aggregation occurred during the first quarter moon. This is similar to recent observations in Abaco and Grand Bahama, which suggests that something different is occurring this year. We’ve also received reports from Bahamian fishermen that the Nassau grouper have also been spawning at odd times this year.
Moving forward, we will continue to work with the guides to determine from how far away bonefish travel to get to this site and the migratory pathways that they use. With our continued tagging, genetic sampling, and reporting of recaptures by guides, we hope to answer these questions which will help to protect the fishery on South Andros.