Note about the presence of the lumpsucker Cyclopterus lumpus (Teleostei, Cyclopteridae) in Galician waters (NW Spain)

The lumpsucker Cyclopterus lumpus Linnaeus, 1758 (Osteichthyes: Cyclopteridae) is a pelagic and solitary species distributed on both North Atlantic Ocean coasts: in the western Atlantic northward from Cape Cod (Massachusetts, USA) to Newfoundland (Canada) and in the eastern Atlantic from the south of Portugal (Vasconcelos et al., 2004) to Greenland as well as to Spitsbergen (Norway) (Holst, 1993) and the Nova Zemlya islands (Russia) in the Arctic Ocean, in addition to an unusual record in the Mediterranean (Dulcic and Golani, 2006). C. lumpus is the target of a substantial number of fisheries in several North Atlantic countries that market the roe as lumpfish caviar. The spawning behaviour and curious parental care of this species is well-known. Lumpfish migrate from the open ocean toward shallow coastal waters during the spawning season. Females lay eggs that adhere to rocks in the seaweed beds. After spawning the females leave the area, while the males look after the eggs until they are hatched (Daborn and Gregory, 1983; Davenport, 1985). Because the geographical distribution of the lumpsucker is preferably colder waters, their abundance and biology in southern Europe are poorly known. Their presence in Galician waters was documented in 1988 (Solórzano et al., 1988), but they were also known prior to this time. The Museum Luis Iglesias de Ciencias Naturais of Santiago de Compostela (Galicia, Spain) has two preserved specimens documenting the first records in Galician waters; these specimens date from 1963 in O Grove (South Galicia), and 1965 in Malpica (North Galicia). The presence of this species in Galician latitudes is actually occasional, but regular, mainly in the first half of the year. Due to their particular globose morphology, these C. lumpus catches frequently surprise and confuse fishermen and often appear as curious news items in the local newspapers. This paper compiles eight records of C. lumpus caught in past years in several shallower locations of southern Galicia (NW Spain) by local fishermen using gill nets (Fig. 1). Date, area, catch depth, total length, sex, total weight and maturity stages of the specimens were taken, when possible (Table 1). Map showing areas and stations where specimens were captured The main morphometric parameters and respective body proportion of four females between 309 and 429 mm standard length (SL) were recorded to the nearest mm. Measurements are given in percentages of SL range, followed by the mean in parentheses: head length 24.4–29.8 (27.0); pre-orbital length: 6.1–10.3 (7.0); post-orbital length: 11.5–14.8 (13.5); eye diameter: 5.4–6.8 (6.0); gill opening length: 17.1–21.7 (19.4); first dorsal base length: 42.7–45.4 (43.3); pre-anal length: 54.9–79.3 (65.7); anal base length: 14.9–17.1 (15.7); pectoral length: 17.2–20.3 (18.2); greater disc diameter: 16.8–19.8 (18.6); lower disc diameter: 15.1–17.8 (15.5); body depth: 59.9–67.5 (63.1) and body width: 32.2–44.6 (35.7). With the exception of one male, all specimens were adult and mature or spawning C. lumpus females. This confirms the south of Galicia as a spawning area for this species and, according to these records, we can establish the spawning period between February and May. This is in accordance with the period established in the NE Atlantic, between February and August (Blacker, 1983). In higher latitudes however, this is displaced to the later months of between April and July in Icelandic waters (Schopka, 1974). The sex ratio is imbalanced and favourable to females by a proportion of 7 : 1. This favourable ratio could probably be conditioned to the spawning season. In the North Atlantic there is a gillnet fishery on the spawning grounds which is directed toward mature females (Albert et al., 2002). Sexual dimorphism, and where females attain greater sizes and outnumber males, and males with more powerful swimming skills than females could be possible reasons to explain these catch differences (Davenport, 1985). We wish to thank the anonymous fishermen and the personnel of Cofradías for providing data and specimens of C. lumpus caught in Galician waters.

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