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Fattorini & Dapporto
Revista de Gestão Costeira Integrada / Journal of Integrated Coastal Zone Management 14(2):185-197 (2014)
richness to obtain a measure of relative conservation.
L
∑ (αi − αmin )
BCC = i=1
L(αmax − αmin )
The BCC is calculated as:
wmawsehsiniieggirhnmeteLudammistootwnhetgehiglaeohllctisatpalhme(ciscoileaanstn.gedgTao)hlrlsiyspsefpoocerifcemisevusru;illcanahtneinordeansbαsei,mnliαatsxyui ,iirsseαstmhmtiheanxewiiimsenidugthehmxet
ranges from 0 (all species belonging to the lower conservation
cepnartedevaginooguryes,rlymαae1=pnp1t l)icetadotetg1oori(dya,lelnαstmipfaeyx)c.pierTsiohbreeitlyoBnCagrCeinasginotdroebxtihoehtoahpsiegbshefeeosnrt
butterflies in Mediterranean islands and European countries
(Fattorini, 2006, 2009b; Dapporto & Dennis, 2008), fish
in France (Bergerot et al., 2008; Laffaille et al., 2011; Maire
et al., 2013), tenebrionids, butterflies, birds and mammals in
the Central Apennines (Fattorini, 2010b, c), and arthropods
in Azorean forest fragments (Fattorini et al., 2012b).
The BCC index is a ‘relative measure’, which means
that it is not sensitive to species richness. This may be an
Figure 1. Location of studied Italian islands. 1: Tuscan Archipelago; advantage to compare species assemblages with different
2: Pontine Islands; 3: Campane Islands, 4: Aeolian Islands; 5: species richness, but poses some problems. For example, an
Ustica Island; 6: Aegadian (Egadi) Islands; 7: Pantelleria Island; 8: assemblage with a single species, haanvinasgsetmhibslasgpeecwieisthαm1ax0,
Pelagian (Pelagie) Islands; 9: Tremiti Islands. The inset shows the would receive the same score as
position of Italy (in black) within the Mediterranean basin. 1stshpp0ieesccspiipeeerssco,wibaelilsetl,hmw9α,iwtmFhaiaxtαthhtmoaαarsxmi.naaOxihaerintgwdhaoleo.rrns(se2ec,0owa1rnei2tbhtah)sαsaieninm<tarbnoαldmaaguasxesc.eeTwmdoibttohhlaveagereBsciCwonmgWitlhee,
Figura 1. Localização das ilhas italianas estudadas. 1 Arquipélago which is calculated as follows:
Toscano, 2. Ilhas Pontinas; 3: Ilhas Campânia, 4: Ilhas Eólias;
Ilhas Ustica, 6: Ilhas Egadi, Ilhas Pantelleria, 8: Ilhas Pelagie,
9: Ilhas Tremiti. Assinalado a negro a posição de Itália na Bacia
Mediterrânea.
L
∑ (αi − αmin )
i=1
BCW = S
∑ (αi − αmin )
i=1
162 km (Linosa, close to North African coasts) (mean ± SD:
34.307 ± 29.886). Island maximum elevation, which may where S is the total species richness for all sites (all other
be considered an indirect measure of habitat diversity, varied symbols as for BCC, see above).
from 0 m (for certain very small islands) to 1019 m (Elba
island) (mean ± SD: 252.140 ± 290.918). To express species vulnerability, we used four different
approaches. In a first approach, we weighted species as
We considered presence data for 139 native tenebrionid an inverse function of their distribution. As the most
species. Taxonomy followed Löbl & Smetana (2008). widespread species occurred on 29 islands, species weights
Cosmopolitan species, such as Alphitophagus bifasciatus, were calculated as the number of inhabited islands divided
Gnathocerus cornutus, Latheticus oryzae, Tribolium castaneum, by 29. Using this weighting scheme in the BCC calculation,
Tribolium confusum, Tenebrio molitor, Tenebrio obscurus, and the most widespread species received an α-value of 1, whereas
Alphitobius diaperinus, which are associated with stored food, species occurring in only one island received an α-value of
were not considered. 29. The BCC calculated using this scheme will be referred
to as BCC1.
Islands were ranked on the basis of the vulnerability
of their tenebrionid communities using the Biodiversity In a second approach, we weighted species using the
Conservation Concern (BCC) index (Fattorini, 2006b) Kattan index (Kattan, 1992), which is based on species
and the Biodiversity Conservation Weight (BCW) index geographical distribution (wide/narrow distribution),
(Fattorini et al., 2012b). In the BCC index, species occurring habitat specificity (broad/restricted habitat specificity) and
in a given area are classified into categories of endangerment abundance (abundant/scarce population) and has been
and weighted by the respective vulnerability. The BCC index previously used to express species rarity in tenebrionid
also combines the vulnerability of each species with total assemblages (Fattorini, 2008b, 2010b, c, 2013a, b). These
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