Fisheries scientists often talk about when a fish may 'enter' a fishery or be at a size that is large enough to be caught by a certain size of tackle. For dolphin, based on a combination of our tagging data and photos shared with us through the years, while rare, we estimate this can occur as early as 6" fork-length (FL). We have had two fish tagged at that size, four at 7", five at 8", and seventeen at 9" FL. It is not until 14" FL, however, that we observe over 500 records or ~1% of our tag release data. Based on this, it appears rare for anglers to catch mahi less than 14" FL, and if those catches occur it is likely situational when anglers are using smaller gear such as small live bait hooks, a sabiki rig, or small lures. Here, we use the large increase in tagging records at 14" to denote the size when dolphin enter the region's recreational fishery.
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Photo: Captain Tim Heiser of Irish Wake shared with us an image of a very small dolphin that took down his outrigger while trolling.
Perrichon et al. (2019) documented the developmental dynamics of dolphinfish and noted at ~13 cm FL, or ~5" FL, dolphin begin the juvenile phase 55 days post-hatch. This puts a fish of that size just shy of two months old. Preliminary results from a comprehensive analysis of growth observed through our tagging data estimate dolphin can grow up to 1" per week. Therefore, we estimate that a 6" FL juvenile dolphin is two months old and a 14" FL fish at a late 3- or
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Figure: Dolphinfish mark and recapture growth models based on different variations of data filtering fit using polynomial regression for fish ranging in size from 14" to 55" FL and up to 557 days at liberty.
early 4-month old fish. With those statistics set, we can now begin to better understand the age of tackle testing bulls and cows that we all dream of catching. With a growth rate of up to 1" per week, or 4" per month, a 3-4 month old fish will be pushing 42" to 46" FL at 11 to 12
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months of age based on the growth rate obtained through our tagging data. Using this information, click here to read about our estimate of the age of Captain Bouncer Smith's incredible recovered fish from years ago (click here) and Captain Carlos 'Chispa' Torres brute (pictured below) caught north of San Juan, Puerto Rico, on September 24th, 2022.
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Photo Caption: Captain Carlos 'Chispa' Torres of the Drop Fishing Charters in Puerto Rico (thedropfishingcharters.com), hoists a 49-pound bull he recently caught during a charter in late September off San Juan, Puerto Rico.
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Pic: Captain Luis Burgos - Caribbean Fishing Academy
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Through September 26th, 2022, 123 vessels have submitted dolphinfish tagging reports, and we are on the verge of surpassing 1,200 fish tagged in 2022. In September, we commenced an acoustic telemetry study off San Juan, PR, whereby 4 dolphinfish, 2 yellowfin tuna, and a silky shark were tagged and released with acoustic transmitters. More on this work in our FAD newsletter due out in a few weeks. For our conventional tagging, please keep in mind that any vessel that reports an angler has tagged 10 or more fish in 2022 will receive a free DRP tee shirt and any boat that tags at least 20 fish will qualify for our year-end awards program. This year, we will be awarding first and second place tagging awards among several categories. For more information on our year-end awards program, check out last year's award winners (click here). Our year-end award sponsors include Star Rods, Costa Sunglasses, AFTCO, and the Guy Harvey Ocean Foundation.
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Fall Fundraising Begins for
2023 Tagging Effort
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If you fish offshore, you likely catch dolphin. You can help support your offshore fishing passion and the conservation and research of one of the top blue water troll
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species in the world by supporting our tagging
program. This year, we distributed a record amount of kits (467) and tags (5,733) and had among the highest amount of vessel participation in our 21-year history. We also deployed 7 satellite tags (9 pending), 7 acoustic tags (7 pending), collected 277 catch per unit effort trips, and 65 seafood reports. Our work is consistently published in scientific manuscripts and referenced in domestic and international fishery management fora, and we need your support to continue. Help us continue and expand in 2023. The ways to financially support our work are provided below.
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| Shop or Donate to Support our
2023 Effort!
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