Shark Depredation and Unwanted Bycatch in Pelagic Longline

Japan Pelagic Longline Fisheries
issues. This approach is believed to provide the most efficient and
ultimately most effective outcome given that bycatch varies according
to operational factors which are only thoroughly understood by
fishermen themselves. In this regard, Japan encourages full utilization
of shark resources, but based on currently available shark CPUE trends,
does not actively advocate shark bycatch reduction to fishermen.
Given the dearth of catch, effort or utilization regulations applicable
to Japanese longline fleets, and the absence of any data on compliance,
the economic, social and ecological effects of the various prohibitions
on, and policies against, shark finning cannot be rigorously evaluated
here. However, some relevant, though anecdotal, information from
the interview program is presented in the following sections.
A5.5. Shark Handling and
Disposition Practices by Fleet
Shark handling and final disposition varies with targeting strategy of
the vessel, and may also change with season, number of days at sea,
recent catch history, and other factors. The following discussion is
organized by fleet (enyo, kinkai and engan) but there is some overlap
in shark handling and disposition strategies between fleets, as well as
important differences within fleets.
A5.5.1. Enyo fleet handling and disposition
The interviewed enyo fishermen and fishery organization
representatives (n=5) explained that in previous decades all shark
species, other than shortfin mako sharks, were finned and the
carcasses were discarded. Because of the value of their meat shortfin
mako carcasses were always retained whole and transported back
to Japan. According to the respondents, the other species’ carcasses
were not retained because there were no markets for shark meat
other than Kesennuma (Japan) and these vessels did not operate out
of Kesennuma.
In recent years, though, markets for shark meat from all species have
developed in some areas. Interview participants listed these areas
as including Cape Town (South Africa), Callao (Peru), Las Palmas
(Spain), Balboa (Panama), Cartagena (Venezuela) and Port Louis
(Mauritius). It was explained that markets do not exist in most other
areas, either because of the absence of infrastructure necessary to
store shark carcasses in frozen form (-30 o C), or a lack of a local or
export market for shark meat. Even where markets do exist, the
current price for shark meat is low: large sharks (≥10kg) sell for ≈ 60
cents per kg and small sharks sell for 20 cents per kg. It was stated that
these markets existed prior to the implementation of shark finning
policies, but it is clear that these low prices are insufficient to motivate
retention of the whole shark carcass by tuna fleets, and one source
admitted that finning will occur unless otherwise prohibited by law.
Therefore, due to finning regulations and other factors, Japanese enyo
vessels do offload shark carcasses for sale in some or all of these areas
during their frequent port calls. 4 The degree to which enforcement
of finning regulations motivates shark meat landing is unknown, but
respondents suggested the level of enforcement in South Africa is
high, and that landing records are checked in Las Palmas.
While shark meat is only beginning to be landed, shark fins have
always been utilized at a high rate. Previous information suggested
that crew composition and compensation policies (McCoy and
Ishihara 1999) can have a strong influence on the number of sharks
finned. The interviewed enyo representatives stated that their
crew was mainly composed of non-Japanese, mostly Indonesians
or sometimes Vietnamese. One respondent agreed that several
years ago special bonuses were offered to non-Japanese crew to
encourage finning. However, he stated that recently the contracts for
Japanese and non-Japanese crew have been standardized. Two other
respondents mentioned that profits from finning are split in shares of
50:50 or 33:66 between the company and the crew.
There were two types of shark handling practices described in the
enyo interviews:
• In one case, all hooked sharks are brought on board, the wire
leader is wrapped around the shark to pin it, and the vertebrae
is cut. If the shark is particularly active, a steel rod is used to
destroy the spinal nerves. The fins are always cut and if there is a
nearby market for shark meat, the carcass will be headed, gutted
and retained.
• Other respondents indicated that large sharks (fins of 20-25
cm or longer at the longest edge, or larger than ≈20-30 kg) are
stunned with a mallet, if necessary, then the vertebrae is cut and
the fins are cut. If there is a nearby market for shark meat the
carcass is headed and gutted and any live embryos released; if
there is no market the carcass will be discarded. Smaller sharks
have the hook pulled out by force and are discarded overboard.
Whether these sharks survive depends on where they were
hooked and how much damage is done by pulling out the hook,
i.e. they are not finned. These fishermen’s perspective was that
it was better not to catch sharks and they were pleased if the set
contained no sharks.
Interview participants stated that even if the rest of the catch is sold
in foreign ports, most fins are retained onboard until the return to
Japan, but a small percentage of fins may be transshipped at sea
or sold in foreign ports. 5 Respondents stated that shark fins will
command a higher price if they are dried, therefore prior to finning
regulations 95% of vessels would dry fins on deck in a windy, though
not necessarily sunny, area. However, in recent years a greater
proportion of fins are being frozen to avoid the conspicuous presence
of shark fins on deck, which is believed to lead to increased at-sea
inspections (particularly in South African waters).
4
In fact, in the three largest foreign landing ports used by the enyo fleet (Callao, Las Palmas and Cape Town), the industry (Japan Tuna) provides support in selling shark meat.
The meat is reportedly destined for European markets in Italy and Spain.
5
There is no formal support by the Japanese tuna industry for the selling of shark fins in foreign ports as this business is reported to be tightly controlled by local syndicates.
93