Highlights from Fish Geek Week North Sulawesi Survey 2012

From previous informal surveys that Gerry Allen had conducted in the 1990’s, he had recorded 712 species from 282 genera and 78 families.

After our survey, we have increased this total to 967 species from 329 genera and 84 families. That’s a 36% increase in species diversity tally and we definitely feel we have lots more to add with additional survey work focused on habitats we didn’t sample on this trip (eg, Mantehage, Nain lagoon, north coast Molas, Bangka-Likupang, and Lembeh). We were nowhere near reaching a plateau – every day adding 25-40 new records to the list!

Moreover, Gerry over the years has developed a “Coral Fish Diversity Index” (CFDI) that allows one to take the numbers of 6 easily seen and censused reef fish families (butterflyfish, angelfish, damselfish, surgeonfish, wrasses, and parrotfishes) and predict the overall diversity. The theory here is that it is hard to truly count all the reef fishes in a site in a short period of time because many of them are highly cryptic and secretive and require a LONG time to truly census them all. By using the CFDI, you can take the numbers of these easily seen “diversity predictor” families and then predict the total diversity. If we do this with Gerry’s original species list from North Sulawesi, he predicted a total of 867 species (less than what we counted on this last go round!). Using our new numbers, the CFDI now predicts 1020 species for North Sulawesi (Bunaken to Lembeh, NOT including Sangihe-Talaud).

To put these numbers in perspective, the entire island of Bali (much larger than North Sulawesi, much better surveyed) has 1022 species recorded to date, Cendrawasih Bay in West Papua (also much larger and better surveyed) has 1000 species recorded to date, and Komodo National Park (roughly same size) has 750 species recorded to date. The Togian and Banggai islands have 819 species recorded to date, Berau in East Kalimantan (including Derawan and Sangalaki) has 875 species recorded to date, and Western Thailand has 775 species recorded to date. Not sure if you want to include this, but the “gold standard” globally is Raja Ampat, which is about 20 times the size of Manado to Lembeh, has 1470 species recorded after 10 years of exhaustive research

Another very interesting point was the extremely high per-site diversity. IN general, any counts of over 200 species on a single dive is considered a very high diversity site. Of the 9 sites that we surveyed, 6 were higher than 200 species (67% of sites), and two of them broke 300 species (Tanjung Kelapa/Malcolm had 310 species and Sachiko had 301 species)! To put this in perspective, in over 40 years’ of survey work around the Coral Triangle region, Gerry Allen has only documented three sites that have broken 300 species: Kayoa Island, Halmahera (303 species), Tanjung Papisoi in Kaimana, West Papua (330 species) and Cape Kri in Raja Ampat (374 species). So Poopoh (Tanjung Kelapa/Malcolm) is now the 3rd richest fish site ever recorded, and Sachiko the 5th.

A related note. We actually surveyed Tanjung Kelapa/Malcolm twice. The first time we didn’t quite do it “properly” and recorded 296 species. The second time Andrea accompanied and guided us and we hit 310 species. Importantly, if we combine the two lists that we generated, the total species count recorded from Tanjung Kelapa/Malcolm is in fact 386 species. This of course is a very big number – it isn’t fair to compare this to the Cape Kri number which was done in a single dive, but it is still valid of course to say that there are nearly 400 fish species recorded from Tanjung Kelapa/Malcolm alone!

Some of the really exciting fish finds for us included both a number of potential new species, as well as a number of exciting range extensions (ie, fishes that were previously not known from anywhere near North Sulawesi) and exceedingly rare fishes that had never before been photographed live that we now were able to photograph in their natural environment.

A quick summary of these include:

Possible new fishes

  • Deepwater Chromis damsel on Bunaken walls

  • Surge zone damsel Chrysiptera brownriggi, that has bright orange stripes through face and may well be a new species

  • Surge zone damsel Chrysiptera cyanea where the males are pure bright blue with no orange in tail and fins which may also be a new species

  • Coral dwarfgoby Eviota that appears new

  • Siphonfish Siphamia that is either new or a never-before live photographed animal

  • Several species of coral goby Trimma that are likely new species

Exciting range extensions

  • Heteroconger cobra. A garden eel that Gerry Allen discovered with Jack Randall from Guadalcanal in the 1970’s and has not been recorded anywhere in 39 years! Not only is this a big range extension, but also we were able to get the only live photographs in existence of this beautiful species

  • Pseudanthias charlenae. A beautiful fairy basslet named after Prince Albert of Monaco’s bride. Previously only known from Bali and West Papua, now known to be common on Bunaken’s deep walls

  • Salarias alboguttatus. A blenny that had never previously been recorded from Indonesia

  • Siganus unimaculatus. A rabbitfish that was previously only known from northern Philippines and Ryuku islands in Japan, as well as one remote population in western Australia’s Rowley Shoals. Now known from Manado as well

  • Meiacanthus crinitus. A fang blenny previously only known from New Guinea and Solomon Islands

  • Trimma papayum. A coral goby reviously only known from Raja Ampat and Flores

  • Tomiyamichthys latruncularias. A shrimp goby previously only known from Red Sea and Maldives, with one record from Java Sea – this is furthest east ever recorded

Exciting photographic records

  • Lutjanus dodecacanthoides, the sunbeam snapper. Described in 1854 from a fish market specimen in Ambon. It has since been recorded from India, Negros (Philippines) and southern Japan, but only from fish market specimens. No live photographs known to exist. We were able to photograph it live!

  • Symphasandon katayamai. Previously only photographed from fish markets in North Sulawesi, but now with a live photo

Mark Erdmann and Gerry Allen

Fish Geek Week