Asian Diver (English) - - Man & Sea -


The dis­tri­bu­tion of marine species is not the same be­tween dif­fer­ent ar­eas of the ocean. Rich­ness dif­fers dra­mat­i­cally be­tween re­gions due to the many pres­sures that have moulded each com­mu­nity over mil­lions of years. The world’s high­est marine bio­di­ver­sity is found in a rel­a­tively small area known as the “Co­ral Tri­an­gle”. The Co­ral Tri­an­gle en­com­passes six coun­tries – Malaysia, In­done­sia, East Ti­mor, Philip­pines, Pa­pua New Guinea and the Solomon Is­lands, which to­gether form a roughly tri­an­gu­lar shape. The fur­ther you travel from the Co­ral Tri­an­gle in any di­rec­tion, the fewer the num­ber of marine species. So, un­sur­pris­ingly, it has been the main hub of re­cent marine dis­cov­er­ies.

And it is just on our doorstep...


This small group of is­lands off the north­ern tip of Palawan in the Philip­pines has of­fered up a num­ber of new dis­cov­er­ies over the years. It ac­com­mo­dates two of the three known dam­selfishes that lack a pelagic lar­val phase and an­other has re­cently been dis­cov­ered from the same area and is in the process of be­ing named. Dam­sels lay their eggs onto the reef and gen­er­ally then guard them. Whilst the fry of the other 380 or so dam­selfishes then float off in ocean cur­rents to dis­trib­ute far and wide, these three sub­se­quently guard their young, which stay in a small group around their par­ents. As a re­sult they never get the chance to reach an­other reef, and the species has be­come trapped only around these few is­lands.


The is­land chain that spans from Bali in the west to Ti­mor and Tan­im­bar in the east has been rich in new dis­cov­er­ies. The is­lands in the chain are very close to each other – the next is­land in the chain is al­most al­ways vis­i­ble – but deep oceanic trenches sep­a­rate them. Strong cur­rents flow through these trenches and im­pact heav­ily on the free move­ment of an­i­mals across the chan­nels. As a re­sult this has been a hot­bed of di­ver­si­fi­ca­tion and many new dis­cov­er­ies have been made in this area. Sev­eral small bot­tom-dwelling sharks such as the Bali and Alor cat­sharks have been dis­cov­ered in re­cent years, as well as the In­done­sian wobbe­gong shark. Sev­eral new flasher wrasses have also be found here, in­clud­ing Renny and Al­fian’s flash­ers from Ko­modo and Alor, re­spec­tively.


The high bio­di­ver­sity of the Bird’s Head Seas­cape is well doc­u­mented, but this spe­cial area has also been the location of many re­cent marine dis­cov­er­ies. Each of the three main ar­eas of the Bird’s

Head have con­trib­uted new and ex­cit­ing dis­cov­er­ies to the cat­a­logue of life. Notably, Cen­der­awasih, Raja Am­pat and Tri­ton

Bay each has its own en­demic species of walk­ing sharks. Whilst the Raja species was dis­cov­ered al­most two cen­turies ago, the other two were only dis­cov­ered and named in 2008.


Tri­ton Bay was first ex­plored in

2006 by sci­en­tists who had been tit­il­lated by other ar­eas of the Bird’s Head. They found this to be an­other en­demic-rich area, with sev­eral species found nowhere else on Earth. Ja­mal’s dot­ty­back and Nur­salim flasher wrasse are two of the most charis­matic, dis­cov­ered in 2007 and 2008 re­spec­tively. Ja­mal’s is a small, but lo­cally com­mon species that mim­ics the black bar chromis, whilst the Nur­salim is as flashy and stun­ning as you’d ex­pect for a flasher wrasse. An­other dot­ty­back that is very rarely seen, and was only named in 2008, is the zip­pered dot­ty­back. They are found at the very lim­its of recre­ational div­ing. It has been sug­gested that two large river out­flows on the bound­aries of the bay act as fresh­wa­ter bar­ri­ers to the spread of these marine species.


Raja Am­pat was the first of the Bird’s Head’s three main re­gions to be prospected for new species. Fun­nily enough, Raja Am­pat was the site of many his­tor­i­cal species dis­cov­er­ies. The blue-finned trevally and black­tipped reef shark both have their type spec­i­mens recorded from Raja Am­pat a cou­ple of hun­dred years ago. Along with an out­stand­ing num­ber of known species, in fact the most of any co­ral reef in the world, there were many new dis­cov­er­ies when sci­en­tists re­dis­cov­ered the area over a decade ago. The ubiq­ui­tous Am­mer’s dot­ty­back was named in 2012 af­ter the div­ing pi­o­neer of this re­gion,

Max Am­mer.


In 2006 Cen­der­awasih was vis­ited for the first time by ichthy­ol­o­gists. They were shocked by the num­ber of new dis­cov­er­ies they made dur­ing the trip. The huge bay has been pe­ri­od­i­cally closed off due to ice ages and tec­tonic plate move­ments. These ef­fec­tively iso­lated the an­i­mals in the bay and over time they evolved into new species, ripe for dis­cov­ery. A glut of new species was named from the bay in the past decade, in­clud­ing Walton’s flasher wrasse, Cen­der­wasih fairy wrasse, Caitlin’s dot­ty­back and Cen­der­awasih but­ter­fly­fish. Just last year an­other en­demic, Mau­rine’s demoi­selle, was named af­ter

Mau­rine Jones in hon­our of her work con­serv­ing the Bird’s Head.

BE­LOW A col­league de­scribed this rare In­done­sian wobbe­gong shark in 2010 us­ing spec­i­mens col­lected at fish mar­kets. He hadn’t seen an im­age of a liv­ing in­di­vid­ual un­til this one (Orec­tolobus lep­to­lin­ea­tus – 2010)

Raja Am­pat Tri­ton Bay Cen­der­awasih Bay This un­de­scribed jaw­fish from Lem­beh Strait, In­done­sia is in the process of be­ing named (Stalix sp. Lem­beh vari­a­tion)

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