Macrourus berglax shrimps, amphipods, polychaete worms, bivalve molluscs, isopods, brittle stars, other echinoderms and comb jellies. The roughhead grenadier is a slow growing fish. The females mature at an age of about 14 years and a length of while males reach maturity at a length of . The potential fecundity of the female is 17,000 to 56,000 eggs. The eggs are laid in batches and spawning takes place at any time of year, with a peak in late winter and early spring. The roughhead grenadier is landed as a by-catch when fishing for Greenland halibut ("Reinhardtius hippoglossoides") and Atlantic halibut ("Hippoglossus hippoglossus").
Permit (fish) Permit (fish) The permit ("Trachinotus falcatus") is a game fish of the western Atlantic Ocean belonging to the family Carangidae. Adults feed on crabs, shrimp, and smaller fish. The permit was first described by the "father of taxonomy", Carl Linnaeus in his tenth edition of the work "Systema Naturae", which was published in 1758. He originally classified it as "Labrus falcatus", though the fish has since been placed in the genus "Trachinotus". The permit's genus name, "Trachinotus" comes from a fusion of the Greek words ' (), which means "rough", and ' (), meaning "back". The species name for the