Coddock? Sea sleuths work to uncover mystery of cod-haddock-like fish
Last summer, I wrote about a very interesting fish, showing up in the Gulf of Maine and promised an update. Well, here it is.
We nicknamed it a “coddock” due to its strange shape and coloration. It has the head of a haddock, the lateral line of a cod, the pectoral fin of a cod, and the meat flaked in large pieces like cod. The body shape is that of haddock, and all the other fins look like haddock fins, but it was missing the “thumbprint of God,” which is a large black spot just behind the operculum (gill plates) and above the pectoral (side fin). It also had spotted skin that looked more like a cod than the silvery skin of a haddock. This was abnormal and deserved some investigation.
As of today, I still have not seen one of these strange fish in person. A few weeks ago, several of the party boats out of New Hampshire caught a few of them.
In case you didn’t read last year’s article, here is a little background.
This fish was first spotted by Linda Hunt, a fish dealer for Coastline Seafood, in the winter of 2023 in a box of fish she was sorting for sale. Linda sent a photo to me and asked if we had ever seen anything like it. It was caught with a school of haddock. While fishermen over the years noticed different coloration variations occasionally, this was different. It really doesn’t look like a cod or haddock.
I took photos and sent them to the University of New Hampshire and the NOAA Northeast Fishery Science Center in Woods Hole, Massachusetts. Everyone was genuinely interested in this fish.
What everyone, including the fishermen, wanted to know was: Were these just a couple of odd-looking fish, or were there more of them in the Gulf of Maine? And secondly, is this just a color variation of a haddock or a new species?
More:Where have all the codfish in the Gulf of Maine gone?
The first question has been answered over the last year. This was not just a one-off occurrence. Many more “coddock” have been caught mostly by recreational fishermen on party boats. This could be due to the closed seasons for commercial fishing and their possible episodic return to this area in the Gulf of Maine. Which brings up more questions. Are these fish all one school? Are they staying together all year, and where are they spawning and when?
So, how do we answer the second question? Is this a new species or just a color variation of a normal haddock? There is only one way to answer this and that is to do extensive DNA testing on the fish. To do this, scientists must collect fin clips of the affected fish. Then, they will need to do a complete DNA workup (sequencing) of the cod and haddock and compare them to a complete workup of the “coddock.” The latest TV shows have us believing that DNA analysis is an easy routine process when it is very complex and a time-consuming endeavor. This is especially the case in animals where the entire DNA genome is not known yet.
Both the NOAA Northeast Science Center scientist, Dr. David Richardson, and UNH Sea Grant scientist, Dr. Linas Kenter, have collected specimens since they showed up last year and have them stored. The easiest and quickest way to begin would be to do a mitochondrial DNA workup of the “coddock.” That would determine the maternal DNA, but this will not give us the entire picture and may not answer our questions. Most likely, they will need to do a complete DNA sequencing to understand the father’s DNA to determine if this is a new species or just a mutation in the genes causing a color variation. This will take time and money.
Meanwhile, both NOAA’s Dr. Richardson ([email protected] ) and Sea Grant Dr. Kenter ([email protected]) are asking anyone who catches one of these fish to contact them and save it by freezing it, or you can contact me at [email protected].
More:What you need to know about sharks that swim in Hampton Beach waters
Dr. Richardson has spoken to the Smithsonian, and they are going to archive a few of the fish in their ichthyology collection for long-term preservation. Everyone is curious about these fish!
As a scientist, this is an interesting development. Do we have a new species? We don’t often get to see evolution in front of our eyes. For years, scientists believed evolution took place over eons due to slight variations and mutations in an individual’s DNA. But is it happening here and now? The big question will be, if we have a new species, how do we manage it? We can, as fishery managers, control human behavior, but we have absolutely no control over nature. This will indeed be a very interesting development to follow on a scientific level and its implications on the fish stocks in the Gulf of Maine. Stay tuned!
Ellen Goethel is a marine biologist and the owner of Explore the Ocean World at 367 Ocean Blvd. at Hampton Beach.
