By Bill Roecker
Here’s a picture of a fish from East Cape. It’s a jack of some sort, and was given to us when we visited Rancho Leonero recently. We asked several scientists to identify the barred critter. We got back two educated guesses.
The first came in the form of a reply to Ed Everett, the gentleman familiar to anglers as the scientist with a measuring stick who checks out bluefin tuna as they arrive in San Diego each summer. The reply came from John R. Hyde, who wrote,” Definitely a Caranx (jack), likely Caranx caninus (Pacific Crevalle Jack). The dark bars are a bit odd but likely a juvenile pigmentation remnant. It doesn't appear to be a full-size adult but the scale is hard to figure...”
The problem with jack crevalle is that they don’t have the same sort of fin arrangement on the back. Also, having caught them from Panama to San Diego, I’ve never seen a jack crevalle with bars as an adult, or with the coloration we see in the picture, or without the dark spot near the base of the pectoral fin.
Paul Sweeney and I spent some time in my library and on the Internet. The only other fish we saw that looked like it might be close was a species called golden trevally. They seemed to be too small, though. Then we got a second educated guess, from an answer to a query for us from Steve Tagami at Mustad. It was from Charles Bergmann, who told us to see this Wikipedia link on Golden Trevally.
Then we went back to Fishbase.org's Golden Trevally page, and had to agree. I wrote Charles, “We’d checked that one at Fishbase.org and written it off. A re-check indicates that does get to the size of this fish, and then some. I believe that’s what it is. The other guess was a jack crevalle, but I’ve never seen one with so much color or those fins and markings. Even the face seems more blunt, stouter. Thanks, Bill”
Charles wrote back, “I had looked at photos earlier but while they had the same characteristics they looked different. I checked others but always came back to the golden trevally, due to the fins and body shape. When I saw this photo it was the same. The difference in head shape could be something to do with sex similar to that with dolphins (dorado).”
So we now think this fish is a golden trevally. What do you think?