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SPATIAL AND SEASONAL PATTERNS IN SPECIES COMPOSITION AND OCCURRENCE OF FISH LARVAE IN THE AREA OF THE CANARY ISLANDS, EASTERN CENTRAL ATLANTIC

species lists of BRITO et al. (2002), Uiblein et al. (1996, 1998), LORANCE et al. (2001), and WIENERROITHER (2003 and 2005) is represented in the larval list. More sampling efforts using more appropriate techniques would certainly allow collecting a higher number of fish larvae taxa and also to possibly obtain more new records from this still underinvestigated area (WIENERROITHER 2005).

4.2.3. New records WIENERROITHER (2005) noted that the current number of fish species in the area of the Canary Islands still may further increase, if the pelagic sampling is continued. Also, previous surveys have not fully covered all habitats as well as the larval stages. One origin of enrichment for the area of investigation is most likely the passive drift of larvae. This can be supported with the new records of WIENERROITHER (2005), as individuals of several fish were near adolescence or even at the juvenile stage. This led him to propose larval transportation via water masses into that area, which is lso supported by the investigations of RODRÍGUEZ et al. (1999). Further, a northward transport of tropical species by the AAIW and also NACW reverse current are one source for new species around the Canary Islands (JOHN et al. 2004a). The Canaries have a subtropical littoral fish fauna, which is related to the one in the Atlantic-Mediterranean biogeographic province (BRITO et al. 2006). This fish fauna has a very low or even non-existent rate of endemism in each archipelago, because currents redistribute species between the islands (BRITO et al. 2006). Genetic studies showed that fish populations of the Azores are more separated from the other Islands (Madeira and Canary Islands), while Madeira and the Canaries are more related to each other and to the European mainland (Portugal and England), which leads to the suggestion of a southward colonization (DOMINGUES et al. 2007). Within the archipelagos of the Canaries, Madeira and Azores the migrations of neritic species show a northwestern trend (DOMINGUES et al. 2006). From the western coast of Portugal to the archipelagos of Madeira and Canaries a southward migration exists due to the transport by the Canary current (DOMINGUES et al. 2007). This southward transport is strongest in spring, summer and winter in the upper 200 m (JOHN et al. 2004a). On the other hand, 80 % of the new records of the littoral fish fauna during the nineties and the first years of the present decade were tropical (BRITO et al. 2005), a fact also observed by WIENERROITHER (2003). JOHN et al. (2004a) have concluded from own and historical data, that species intruded the Canary Islands from the northwards flow of NACW and SW in autumn. JOHN et al. (2004a) mentioned that northward currents add 4 to 8 tropical specimens per squaremeter to the native oceanic fauna. It is also thought that filaments can contribute neritic larvae from the African shelf to the local neritic populations of the Canary Islands (RODRÍGUEZ et al. 1999). The gadiform species Melanonus zugmayeri is distributed worldwide in tropical to temperate seas and inhabits the mesoand bathypelagic realm (COHEN 1984). Within the northeastern Atlantic M. zugmayeri is most common around the Azores, Madeira and west of the Canary Islands. So it is not astonishing to encounter this species around the islands, since interconnections due to migration between these islands (DOMINGUES et al. 2006 and 2007) and a southward transport within the season of spring (JOHN et al. 2004a) are common. Argentina sphyraena has been also recorded along the coast of Europe and Mediterranean Sea and along the coast of West Africa and inhabits the shelves and slopes (COHEN 1984). Since larvae were found around the western islands, which are most influenced by the African upwelling, it is most likely, that the larvae were entrained by an upwelling filament from the Marroccanean coast. The temperate Crystallogobius linearis inhabits the coastal habitat as well as the pelagic realm down to a depth of 400 m along the Atlantic European coast and the Mediterranean Sea (MILLER 1984). The Canary Islands are the southernmost record

Inf. Téc. Inst. Canario Cienc. Mar. n°13

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Spatial and seasonal patterns in species composition of fish larvae in the Canary Islands  

Technical report consisting on a comprehensive annotated larvae taxa list with the most important taxonomic characters of this region

Spatial and seasonal patterns in species composition of fish larvae in the Canary Islands  

Technical report consisting on a comprehensive annotated larvae taxa list with the most important taxonomic characters of this region

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