Whaler Sharks - seafdec.org.my

S h a r k s a n d R a y s o f B o r n e o
Table 1 Proportional species richness (%) of shark and ray groups across the region.
Higher taxa
NW Philippines Indonesia Borneo
Australia
Heterodontiformes 1 1 - 1
Lamniformes 5 6 6 2
Orectolobiformes 7 6 6 7
Carcharhiniformes 31 32 33 31
Hexanchiformes 2 2 2 1
Squaliformes 12 10 10 2
Squatiniformes 1 1 1 1
Pristiphoriformes - 1 - -
Pristoidei 3 2 1 3
Rhinoidei 1 1 1 1
Rhynchobatoidei 1 2 2 2
Rhinobatoidei 2 3 4 2
Platyrhinoidei - 1 - -
Torpedinoidei 3 4 1 4
Rajoidei 8 7 1 4
Myliobatoidei 20 21 33 38
Chimaeriformes 3 2 1 1
TOTAL 179 164 139 118
this may be due to the comparative paucity of deepwater habitats near the coast. Clearly
the richest chondrichthyan families in all regions, the whaler sharks (Carcharhinidae)
and stingrays (Dasyatidae), both attained the highest relative proportions of any fauna in
Borneo (Table 2). Also, eagle rays (Myliobatidae) and devil rays (Mobulidae) are more
diverse in this region than off Australia. Once again, deepwater subgroups, such as the
gulper sharks (Centrophoridae), spurdogs (Squalidae) and lantern sharks (Etmopteridae),
were absent from the ten main families.
Shelf demersal species, comprising about 70% of the fauna, are more dominant in Borneo
than in other regions (Table 3); conversely, the proportions of outer shelf and slope species
are comparatively low. Freshwater and estuarine species comprise almost 7% of the fauna;
by far the highest proportion of any region and this may be linked to the diversity of
these habitats in the region.