IUCN Red List Assessment
Red List Category
CR
Critically Endangered
Red List Criteria
C2a(i,ii); D
Version
3.1
Year Assessed
2004
Assessor/s
Smith, B.D. & Beasley, I.
Reviewer/s
Reeves, R. & Taylor, B.L. (Cetacean Red List Authority)
Justification
The extremely low numbers of dolphin groups detected during the 2001 and 2002 surveys and the absence of sightings during the 2003 survey indicate that the population in Songkhla Lake certainly contains fewer than 50 mature individuals. The evidence is particularly strong when these survey results are compared to the sighting rates recorded for the Critically Endangered Malampaya Sound Irrawaddy dolphin subpopulation (see Smith et al. in press). Therefore, the Songkhla subpopulation qualifies for listing as CR based on Criterion D. It also qualifies as CR on the basis of Criterion C2a (i,ii) as there are certainly fewer than 250 mature individuals in the subpopulation, a continuing decline in the number of mature individuals is projected or inferred based on the ongoing threat from gillnet entanglement and capture in fishing traps, and both subcriteria of subcriterion 2a apply (no subpopulation contains more than 50 mature individuals and more than 90% of the total mature individuals are in one subpopulation).
