2012. Review of Significant Trade - Cites

Tursiops aduncus
In an interim report on the Solomon Islands Dolphin Project submitted to the 25 th meeting of
the Animals Committee (AC25 Inf. 11, hereafter referred to as “Oremus et al., 2011”), it was
reported that specimens of T. aduncus (36 animals), held in captivity in the Solomon Islands
in November 2009 were all captured along the coast of Guadalcanal.
Population trends and status: There is no global abundance estimate for the species, and
the current population trend is unknown (Hammond et al., 2008). T. aduncus is currently
listed as Data Deficient in the IUCN Red List, with the following justification: “Although the
species is widespread in Indo-Pacific coastal waters and its aggregate abundance is probably
in the tens of thousands in multiple local populations, habitat destruction and incidental
takes (of unknown but possibly large magnitude) may have a significant impact on this
species. However, the lack of available information precludes an assessment of this impact”
(Hammond et al., 2008).
Published population estimates and information on population trends are lacking for the
Solomon Islands. However, recent surveys led by the South Pacific Whale Research
Consortium (SPWRC) as part of the Solomon Islands Dolphin Project took place in
November 2009 and November 2010 around four main islands of the eastern Solomon
Islands: Santa Isabel, Malaita, Guadalcanal and the Florida Islands up to 1 nautical mile
offshore (Oremus et al., 2011). In 2442 nautical miles surveyed (1707 nm of coastal effort and
735 nm of offshore effort), thirty groups of T. aduncus were encountered over the two survey
years (14 groups in 2009 and 16 in 2010), with 184 unique individuals photographed
(Oremus et al., 2011). The average group size was 7-9 individuals, but group size varied from
1-30 individuals (Oremus et al., 2011). Further aerial surveys took place in July 2011,
however results will not be available until the end of 2011 (Marc Oremus, pers. comm., 2011).
Kahn (2006) recorded only one group of T. aduncus comprising 11 individuals and no calves
near Gizo (off New Georgia Island) despite a relatively large survey effort of over 60 hours
in 2004, indicating that the species may have a relatively low abundance in the western
provinces of the Solomon Islands, at least during the survey period. Defran recorded at least
113 distinct individuals from photo-identification data, with five dolphins being recorded in
all three survey years and seventeen being sighted over adjacent study years (2005 and 2007
or 2007 and 2008) (Reeves and Brownell, 2009). Forty individuals were identified by Defran
more than once in the same survey trip, suggesting short- or medium-term site fidelity
(Reeves and Brownell, 2009).
According to Parsons et al. (2010), the Solomon Islands Government presented information
on previous studies of the species in support of a non-detriment finding for the 2007 exports.
This indicated that 52 individuals had been located in four days of boat trips in 2005, and
46 individuals had been sighted in eight days in 2007 (seven recorded more than once),
covering a total of 31 miles of coastline. Based on high recapture rates, Parsons et al. (2010)
suggested a relatively small, resident population in the locations surveyed in 2005 and 2007,
and that these data could suggest a population in the low hundreds. Similarly, Reeves and
Brownell (2009) suggested a likely “small” population (i.e. in the hundreds) in the Solomon
Islands, considering the restricted areas of potentially suitable habitat.
In 2009, the Solomon Islands Ministry of Fisheries and Marine Resources (in litt. to CITES
Secretariat, 2009a) estimated a population size of 12 000-15 000 T. aduncus. A slightly lower
population estimate was provided to delegates of AC24, along with the basis for its
calculation (Ministry of Fisheries and Marine Resources, 2009b): based on local sightings of
5.8 animals per km of shoreline (species unspecified), and unpublished research by R.H
Defran (as reported to the Scientific Authority) of 4.1 animal sightings per km of shoreline
(species unspecified), data were extrapolated using the total Solomon Islands shoreline of 9
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