In September 2012, Dr Mark Erdmann and Dr Gerry Allen were visiting Manado as Guest Lecturers for a biology workshop. At the same time they conducted a survey of fish species to measure the marine biodiversity in North Sulawesi, and it threw up some most absolutely amazing unexpected results. Namely that North Sulawesi has more marine diversity than Komodo and West Thailand, so now you can dive some of the best marine diversity on the planet with us!
How did this reach this conclusion? To begin with, they recorded 967 species from 329 genera and 84 families, and they said that they were “nowhere near reaching a plateau with every day adding 25-40 new records to the list!”.
Also, using Gerry’s own diversity index, they found that North Sulawesi has some of the best marine diversity in Asia, easily beating diving locations like Komodo and Western Thailand. With the index, Gerry predicts 1020 species for North Sulawesi (Bunaken to Lembeh), this compares to:
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 surveyed, 6 were higher than 200 species, and two of them broke 300 species (Poopoh/Tanjung Kelapa had 310 species and Satchikos’ had 301 species).
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’s the 5th!
We always knew North Sulawesi had wonderful marine biodiversity, given that it sits at the heart of the Coral Triangle, but they definitely did NOT expect these results!
Here is their full survey result:
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 (week in Minahasa Lagoon + 5 informal days in Lembeh Strait), 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 (Poopoh/Tanjung Kelapa had 310 species and Satchikos’ 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 Satchiko’s 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:
Exciting range extensions:
Exciting photographic records:
Mark Erdmann and Gerry Allen
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