Fish Species Biodiversity on Trawlable Bottoms of South Adriatic Basin (Mediterranean Sea)
Groundfish biodiversity on trawlable bottoms of the South Adriatic basin was analysed by means of univariate ecological indices. Raw data came from three experimental trawl surveys carried out in the mentioned area during the summer 1996, 1997 and 1998. The surveys (112 samples per survey) provided a total list of 113 groundfish species (98 teleosts, 15 selachians). Margaleff (richness), Shannon (diversity) and Pielou (evenness) indices were estimated; the index values per sample were mapped by kriging method, and mean values for each survey were computed in order to detect yearly and/or spatial differences (shelf and slope zone, East and West coast).
The global analysis of the diversity of the groundfish species on the trawlable bottoms of the South Adriatic Sea did not show any particular trend over the triennium 1996-98, in spite of some significant differences among the years. The main changes concern the “shelf” ecological indices, while the “slope” situation appears to be reasonably stable; East (Albania) “shelf” values are generally higher and more homogeneously distributed than the West shelf (Italy) ones.
KeywordsOrdinary Kriging Trawlable Bottom Trawl Survey Ecological Index Groundfish Species
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- Alfirevic S (1981) Contribution à la connaissance des caractéristiques bathymétriques et sédimentologiques de l’Adriatique. FAO Fish 253: 43–52Google Scholar
- Artegiani A, Aiiolini R, Paschini E (1981) Seasonal thermocline evolution in the nordiern and middle Adriatic Sea. FAO Fish Rep 253: 55–64Google Scholar
- Bello G, Rizzi E (1988) I teleostei raccolti nell’Adriatico meridionale nelle campagne sperimentali di pesca a strascico 1985–87. Quad Ist Ric Pesca Marit 5: 77–90Google Scholar
- Bertrand J (1996) Campagne internationale de chalutage démersal an Méditerranée (MEDITS): campagne 1996. Rapp Final Rapp Contrat CEE-IFREMER-IEO-SIBM-NCMR (MED/95/19/54/65/27) 1–2: 1–71Google Scholar
- Buljan M, Zore-Armanda M (1979) Hydrographic properties of the Adriatic Sea in the period from 1965 through 1970. Acta Adriat 20: 1–368Google Scholar
- Caddy JF, Griffiths RC (1995) Living marine resources and their sustainable development. FAO Fish Tech Pap 353Google Scholar
- Caddy JF, Sharp GD (1986) An ecological framework for marine fishery investigations. FAO Fish Tech Pap (283): 152 p.Google Scholar
- Castino M, Roletto E (1991) Statistica applicata. Piccin, PadovaGoogle Scholar
- Holden MJ (1974) Problems in the rational exploitation of elasmobranch populations and some suggested solutions. In: Harden Jones FR (ed) Sea fisheries research. Halsted Press, J. Wiley and Sons, New York, pp 117–137Google Scholar
- Magurran AE (1991) Ecological diversity and its measurement. Chapman and Hall, LondonGoogle Scholar
- Ungaro N, Marano G, Rizzi E, Marzano MC (1996) Demersal Squaliformes and Rajiformes in the South-Western Adriatic Sea: trawl-surveys 1985–1994. FAO Fish Rep 533 Suppl: 87–96Google Scholar
- Ungaro N, Marano G, Vlora A, Martino M (1998a) Space-time variations of demersal fish assemblages in South-Western Adriatic Sea. Vie Milieu 48: 191–201Google Scholar