ecological effects of marine protected areas empafish project ...

EMPAFISH Booklet no. 1 Ecological effects of Atlanto-Mediterranean MPAs in the EU
Serra Gelada – Benidorm islets: ecological studies
� General
o Fish assemblages
Fish assemblages have been extensively studied in the area since 1996, using
underwater visual census (UVC) as main sampling technique. The principal
objective has been to study the temporal and spatial variations of fish
assemblage at several spatial scales, from 10s to 1000s metres (Bayle 2002;
Forcada 2004). Metallic trace elements were studied in otholits of D. vulgaris
to define their suitability as a markers to assess the spillover from MPAs
(Gillanders et al. 2001), and the results showed a very low variability among
different locations along Alicante coast.
o Benthic assemblages
Some technical studies were carried out on the distribution and abundance of
Pinna nobilis (Sánchez Jerez et al. 2003), Dendropoma petraeum (Bayle et al.
2004) and echinoderms (Sanchez Jerez et al. 2005). Density of edible sea
urchins (P. lividus) was six times higher within the SGIBNP. Descriptive
studies on maërl beds and the associated macrofauna were carried out in
Serra Gelada – Islets of Benidorm Natural Park (Barberá et al. 1999, 2003;
Bordehore et al. 2000a, 2000b, 2003).
� Indirect effects (trophic cascades, changes in assemblage –
trophic structure, etc.)
Studies about changes in fish assemblage structure, as well as on sea urchins
(see above) can be considered in the framework of indirect (trophic) effects of
protection.
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