Friday, May 30, 2008

Worryingly fascinating species estimates...

Fascinatingly, I have just calculated the expected species total for TARP based on an apparently robust Coral Fish Diversity Index (CFDI - see p.46 of the Raja Ampat report) devised by Gerry Allen (calculated by adding together species in six Index families - ACANTHURIDAE, CHAETODONTIDAE, LABRIDAE, POMACANTHIDAE, POMACENTRIDAE, SCARIDAE & multiplying the resulting CFDI by 3.39, and then subtracting 20.6). Given my CFDI for TARP of 104, I predict a total of 332 fish species in the park (i.e. 33 to see; 31 if you include the Whale shark and accompanying Pilot fish filmed recently by Mark Hedger).

Worryingly however, Allen also mentions in a table on p.48 of the Raja Ampat report that surveys in TARP (I believe he was referring to his own unpublished survey made in 1992 of which I can not find a copy) gave a CFDI of 139 with an estimated fish species richness of 450 (against 357 actual species he found which he puts down to incomplete sampling). I don't want to believe the implication that 25% of 1992's fish species no longer exist in TARP. I'd prefer to believe that I am simply an incompetent and amateurish fish-watcher, because if not, what will the future bring for TARP?

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