Sheepshead Porgy, Calamus penna
The Sheepshead Porgy, Calamus penna, whose common Spanish name is pluma manchada is a member of the Porgy or Sparidae Family, known collectively as plumas in Mexico. Their common name derives from the fact that their teeth resemble those found in sheep. Globally, there are thirteen species in the genus Calamus, nine of which are found in Mexican waters, eight in the Atlantic and one in the Pacific.
The Sheepshead Porgies are characterized by their “porgy-like” laterally compressed relatively thin bodies (compared to other Porgies); their body is deepest at the base of the beginning of the dorsal fin and has a depth that is 40 to 42% of standard length. Overall they have a silvery coloration with iridescent blue, lavender, and yellow reflections. They have approximately seven dark bars on their sides which fade quickly upon death. They have a dark brown bar under their eyes and most fish also have a blue-gray line under their eyes. They have a small black spot at the base of their pectoral fin. Their head has no blue, orange or yellow markings. Their head is deep and evenly convex, and lacks a steep upper profile. They have a blunt snout with a moderately large mouth that reaches under the front edge of their eyes. They are equipped with molar teeth on the sides of each jaw and equal sized canines at the front of each jaw that are used to crush hard shell prey. Their anal fin has a short base with three spines and 10 or 11 rays; their caudal fin is forked; their dorsal fin is low with 12 or 13 spines and 12 rays; and their pectoral fins are short just reaching to the anal fin origin.
The Sheepshead Porgies are a common coastal species and are abundant throughout most of their range; they are found over hard bottoms, within ledges and caves, within coral reefs and associated gravel, and in grass and sand areas along the outer continental shelf at depths up to 300 feet. Juveniles are found within seagrass beds (Thalassia). They reach a maximum length of 46 cm (18 inches) but measure around 28 cm (11 inches) on average and can weigh up to 1.0 kg (2.2 pounds). They are bottom dwellers that feed primarily on invertebrates including barnacles, crabs, mollusks, polychaetes, sea stars, and sea urchins. They are protogynous hermaphrodites with all fish starting out as females and changing to males at midlife. Each female releases thousands of eggs which are fertilized externally by males then become pelagic.
The Sheepshead Porgy is very similar in shape to seven other Porgies found in Mexican waters of the Atlantic, however, it is the only Porgy with a significant barring pattern on its sides. It is often confused with its namesake, the Sheepshead, Archosargus probatocephalus, which is also from the Porgy Family but has a very prominent barring pattern and an oval fusiform body profile.
In Mexican waters the Sheepshead Porgy are found in all waters of the Atlantic.
The Sheepshead Porgies are considered an excellent food fish and are targeted by commercial and recreational fishermen being marketed both fresh and frozen. There are reports however, that they contain Cigua Toxin. They are caught primarily by hook and line, longlines, bottom trawls, and fish traps. They are caught predominately as a by-catch of grouper and shrimp fisheries. From a conservation perspective they are currently considered of Least Concern and unregulated in most parts of their range (except for coastal waters of the southeast United States). It is generally believed that their commercial and recreational landings as well as their body length have decreased over the last 10 years, although these findings have been poorly documented. They are subject to habitat destruction and overfishing in some parts of their range.
Sheepshead Porgy, Calamus penna. Fish caught from the Florida Middle Grounds, March 2015. Length: 56 cm (22 inches). Catch, photo and identification courtesy of George Brinkman, Guelph, Ontario, Canada.