Kyne & Simpfendorfer.. - Shark Specialist Group

SECTION III.
DEEPWATER CHONDRICHTHYANS AND FISHERIES
There is a general lack of available trade and landings data for deepwater chondrichthyans
(Cavanagh and Kyne 2005). Indeed, statistics are often lacking for catches of sharks, rays and
chimaeras in general. Globally, the chondrichthyan fishes represent approximately 1% of total
fisheries production (Bonfil 1994), although the reported catch has been increasing over the
past three decades (Stevens et al. 2000, FAO FIGIS database). Many deepwater species are
taken as bycatch, often discarded, or landed under generic species-codes such as 'shark' or
'other'. It has been suggested that 50% of the world's catch of chondrichthyans is taken as
bycatch (Stevens et al. 2000) and while Bonfil (1994) suggested that the actual annual catch
of chondrichthyans may be twice as high as the reported catch, Clarke et al. (2006) postulated
that the biomass of shark involved in the shark fin trade is 3–4 times higher than reported
catch statistics indicate.
As traditional marine resource stocks are depleted, global demand for fish products increases
and fishing technology advances, fisheries are moving into deeper water and new commercial
deepwater fisheries are continuing to develop (Gordon 1999, Lack et al. 2003, Morato et al.
2006). The lack of accurate catch data, including the under-reporting of catches, the lack of
recording bycatch, poor taxonomic resolution and species-identification, and illegal fishing,
makes an assessment of the global catch of deepwater chondrichthyans extremely difficult.
This Section reviews available fisheries data on deepwater chondrichthyans utilizing FAO
(the United Nation's Food and Agriculture Organization) fisheries statistics to overview trends
in global and regional production of deepwater chondrichthyans. There are considerable
limitations to this data and these are discussed in this Section. Additionally, a number of case
studies are presented covering southern Australia, the Northeast Atlantic, the Azores, the
Maldives and Namibia. For some of these case studies, actual catch data is not available, but
they are discussed to demonstrate a collapse in a deepwater shark fishery (Maldives) and
approaches to the precautionary management of a developing deepwater shark fishery
(Namibia).
GLOBAL PRODUCTION OF DEEPWATER CHONDRICHTHYANS, 1950-2004
Status: Increasing but fluctuating trend in global production. Poor data resolution and
under-reporting make this analysis of questionable accuracy, and together with bycatch
issues and illegal fishing, make an assessment of global trends extremely difficult.
The FAO FIGIS database provides global production statistics for fish and other living marine
resources for the years 1950 to 2004. Data were extracted for production statistics of all
'deepwater' chondrichthyans, that is for species or species groups that are listed in Section I of
this report (annotated checklist of deepwater chondrichthyans). Table 3.1 outlines the FAO
database categories and their corresponding scientific names that were used in this analysis.
Global and regional (by major ocean region) production figures are presented for 1950–2004
for all deepwater species categories combined. The major ocean regions used are based upon
the FAO's Major Fishing Areas for Statistical Purposes as outlined in the introduction of
Section I of this report. Data for major ocean regions were compiled by extracting data for all
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