The IUCN/SSC Shark Specialist Group
Shark News 6: March 1996
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Request for information on
sawfishes, family Pristidae
The Shark Specialist Group is becoming increasingly concerned
about widespread reports (both from anecdotal accounts and, less
commonly, reviews of historic fisheries data) of an apparently serious
decline over the past few decades of formerly healthy populations of
all species of sawfish. Similar patterns are appearing in most of the
warm-temperate to tropical regions of the world, and we would
greatly welcome any comments from readers on this subject.
This unusual family of rays is difficult to confuse with other
species (with the possible exception of the very rare sawsharks).
Additionally, because of their bizarre appearance, sawfish are generally
readily noticed and well recorded (or at least remembered) where
they are present or have occurred in the past (albeit not always
accurately to species). Their saws are commonly preserved in fishing
villages, local museums or as tourist curios, and may appear in the
marine curio trade, thus often enabling species to be identified. These
characteristics make it relatively easy to determine regional patterns
of fisheries yields, even if only on an anecdotal basis.
The pattern of decline reported so far can be broadly summarised
as follows: relatively large (or at least reliable) catches prior to the
1960s, followed by a period during the 1960s and 1970s when a steep
decline in catches was widely reported, followed by very infrequent
records into the 1980s and 1990s. Tyson (pers. comm.) suggests that
one of the major reasons for the decline was the big increase in gillnet
fishing worldwide around 1960, when cheap and very effective nylon
fibre gillnets became widely available. Adams (pers. comm.) indicates
that the smalltooth sawfish Pristis pectinata may have gone into
decline a little earlier than this in the south-eastern United States,
where intensive commercial and recreational fishing appear to have
had an earlier impact.
Readers are requested to pass on to the editors, Sarah Fowler or
Merry Camhi, any information they may have on trends in sawfish
catches, whether based on fisheries records, accounts in literature,
or indeed anecdotal information (but please indicate your sources
clearly and, if at all possible, the species involved).
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