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Since the last century, the richness of the Canary Islands marine flora has attracted many botanists. Børgesen's seminal papers have been the main reference source for anyone interested in this flora. The first checklist of the marine macroalgae from the Canary Islands was published by Gil-Rodríguez and Afonso-Carrillo (1980a) with 434 macroalgal species being listed together with some dubious records. In recent years, the research efforts of local phycologists and the output of some scientific expeditions have yielded some new species and a large number of new records to the Canarian seaweed flora. The aim of this contribution is to compile an up-to-date catalogue of the marine plants for the Canary Islands (including cyanobacteria, macroalgae, seagrasses and fungi). The review of all published records of these marine plants takes into account the present taxonomic status and nomenclatural changes of the taxa concerned and rejects old and dubious records. After a careful review of the pertinent references and revision of live and preserved material, only valid records published before July 2001 are included in this checklist. Besides, each species is quoted for the islands in an east-west fashion to illustrate the distributional pattern of the species concerned. The marine flora of the Canary Islands is composed of 711 species, which are distributed as follows: 59 Cyanophycota, 385 Rhodophycota, 125 Chromophycota, 117 Chlorophycota, 3 seagrasses and 22 fungi. Compared to nearby regions, the Canarian archipelago comprises a much larger number of species. This high diversity appears to be the result of the combined effects of its geographic location, paleoclimatic events and the prevailing oceanographic conditions. [ABSTRACT FROM AUTHOR]

Fish populations on two different types of artificial reefs (oceanic and coastal) in the Canary Islands have been studied for several years by means of the Point Count visual census method. A total of 53 species were observed at both reefs. The isolated oceanic reef was associated with benthic rocky bottom species, as well as with a large seasonal influx of small pelagic fish. Also, several predator fish from the nearby sandy bottom biotope became associated with the modules. The increased abundance of predators such as Synodus spp. coincided with a dramatic reduction in recruits and juveniles of some commercially and recreationally important fish species. Copyright 2002 International Council for the Exploration of the Sea. Published by Elsevier Science Ltd. All rights reserved. [ABSTRACT FROM PUBLISHER]

We carried out 84 trawls in 41 seagrass meadows composed of the phanerogam Cymodocea nodosa at three islands of the Canarian Archipelago, during June to September 2003, in order to describe the associated ichthyofauna (composition, richness, and abundance), to analyze the role that this habitat can play in fish recruitment, and to determine the potential relationship between the spatial structure of the seagrass meadow and the patterns of richness and abundance of the fish assemblage. A total of 8298 individuals were captured. The five most relevant species, in terms of abundance and frequency, were Spondyliosoma cantharus, Diplodus annularis, Syngnathus typhle, Mullus surmuletus, and Pagellus erythrinus. Gran Canaria had the largest species richness (36 species) and mean number of species per sample (8.69 ± 0.49; mean ± SE). Lanzarote had the largest number of individuals (64.83% of the total registered) and mean total abundance per sample (168.39 ± 30.91). High densities of individuals were registered (95.86 ± 13.5) and 92.91% of fishes were juveniles. Our data showed that the physical configuration of the seagrass meadows did not significantly affect the patterns of richness and abundance of the associated fish assemblage. In conclusion, the C. nodosa meadows exhibited a singular ichthyofauna and they contribute to the maintenance of the diversity of the coastal fish assemblages in the Canarian Archipelago. This habitat constitutes, during spring and summer, a nursery habitat for juvenile fishes of many species, several of them commercially targeted. [ABSTRACT FROM AUTHOR]

We assessed the effectiveness of two marine reserves (MRs) in the Canary Islands (eastern Atlantic), called ‘Punta La Restinga-Mar de Las Calmas’ (El Hierro Island) and ‘Isla La Graciosa e islotes del norte de Lanzarote’ (Chinijo Archipelago). Specifically, we evaluated the variability in the abundances and biomasses of four commercially-targeted fish species: the parrotfish (Sparisoma cretense), the island grouper (Mycteroperca fusca), the white sea-bream (Diplodus sargus cadenati) and the zebra sea-bream (Diplodus cervinus cervinus). Four fishing management categories were established within and around each MR: (1) a no-take or integral area (collection of all animals is not permitted), (2) a buffer area (fishing is permitted with traditional fishing gears), (3) a neighbouring fishing area (<20 km), and (4) a fishing area off a neighbouring island. Two randomly selected sites were sampled within each management category and MR in October and March 2004. Univariate tests provided evidence of a moderate ‘reserve effect’ for both MRs consistent through time. Differences in abundances and biomasses of each species among management categories were clearly species-specific and inconsistent between both MRs. Species of the genus Diplodus showed greater abundances and biomasses within protected locations compared to unprotected locations at El Hierro Island. Moreover, the four selected species showed greater abundances and biomasses in the locations surveyed at El Hierro Island compared to unprotected locations at the neighbouring island. In contrast, S. cretense appeared to be the only species that benefited from protection in the Chinijo MR. Differences in the sizes of the MRs, the fishing effort around the MRs and the effectiveness of the enforcement within each MR, appeared to be possible explanations for the patterns observed. [ABSTRACT FROM AUTHOR]

We assessed the effectiveness of two marine reserves (MRs) in the Canary Islands (eastern Atlantic), called "Punta La Restinga-Mar de Las Calmas" (El Hierro Island) and "Isla La Graciosa e islotes del norte de Lanzarote" (Chinijo Archipelago). Specifically, we evaluated the variability in the abundances and biomasses of four commercially-targeted fish species: the parrotfish (Sparisoma cretense), the island grouper (Mycteroperca fusca), the white sea-bream (Diplodus sargus cadenati) and the zebra sea-bream (Diplodus cervinus cervinus). Four fishing management categories were established within and around each MR: (1) a no-take or integral area (collection of all animals is not permitted), (2) a buffer area (fishing is permitted with traditional fishing gears), (3) a neighbouring fishing area (<20 km), and (4) a fishing area off a neighbouring island. Two randomly selected sites were sampled within each management category and MR in October and March 2004. Univariate tests provided evidence of a moderate "reserve effect" for both MRs consistent through time. Differences in abundances and biomasses of each species among management categories were clearly species-specific and inconsistent between both MRs. Species of the genus Diplodus showed greater abundances and biomasses within protected locations compared to unprotected locations at El Hierro Island. Moreover, the four selected species showed greater abundances and biomasses in the locations surveyed at El Hierro Island compared to unprotected locations at the neighbouring island. In contrast, S. cretense appeared to be the only species that benefited from protection in the Chinijo MR. Differences in the sizes of the MRs, the fishing effort around the MRs and the effectiveness of the enforcement within each MR, appeared to be possible explanations for the patterns observed. [ABSTRACT FROM AUTHOR]

A hierarchical sampling design was used to study the population structure and the horizontal (differences among islands, locations within islands and sites within locations) and vertical (differences among intertidal bands) distribution patterns of the gastropod molluscs Osilinus atrata and O. sauciatus along the rocky intertidal zone of the Canary Islands. Differences in the spatial patterns of abundance, size and distribution were recorded for both species. Osilinus atrata was more abundant than O. sauciatus throughout the archipelago. Its abundance varied among islands and it presented a heterogeneous distribution in the bands from one island to another, though it was more frequent in the middle and high bands. Osilinus sauciatus was only found at the eastern islands and did not exhibit significant differences between the bands, even though 91.35% of the individuals appeared in the high band and the rest in the middle band. On the other hand, O. sauciatus had a larger mean size than O. atrata, but both species presented the largest mean sizes in the high band. [ABSTRACT FROM AUTHOR]