than normal productivity; for example in 1962 and 1967, and to a lesser extent, 1974 and 1999. These result in a more southerly distribution of the fish and have a strong effect on the biomass of the spawning stock, but because of high fishing mortality, these revivals do not have any lasting effect on the population. In general, there was above average recruitment from the 1960s up to the early 1980s, similar to recruitment for Atlantic cod and whiting, this has been called the gadoid outburst. There was strong recruitment in 1999 but since then, the recruitment rate has been very low. Parasites Cod and related species are plagued by parasites. For example, the cod worm, Lernaeocera branchialis, starts life as a copepod, a small, free-swimming crustacean larva. The first host used by cod worm is a flatfish or lumpsucker, which they capture with grasping hooks at the front of their bodies. They penetrate the lumpsucker with a thin filament which they use to suck its blood. The nourished cod worms then mate on the lumpsucker. The female worm, with her now fertilized eggs, then finds a cod, or a cod-like fish such as a haddock or whiting. There, the worm clings to the gills while it metamorphoses into a plump, sinusoidal, wormlike body, with a coiled mass of egg strings at the rear. The front part of the worm's body penetrates the body of the cod until it enters the rear bulb of the host's heart. There, firmly rooted in the cod's circulatory system, the front part of the parasite develops like the branches of a tree, reaching into the main artery. In this way, the worm extracts nutrients from the cod's blood, remaining safely tucked beneath the cod's gill cover until it releases a new generation of offspring into the water. Taxonomy and etymology The haddock was first formally described as Gadus aeglefinus in 1758 by Carolus Linnaeus in the 10th edition of volume one of his Systema naturae with a type locality given as "European seas". In 1862 Theodore Nicholas Gill created the genus Melanogrammus with M. aeglefinus as its only species. The generic name Melanogrammus means "black line", a reference to the black lateral line of this species. The specific name is a latinisation of the vernacular names “Egrefin” and “Eglefin”, used in France and England. Fisheries Haddock is fished year-round using gear such as Danish