Shark Depredation and Unwanted Bycatch in Pelagic Longline

Appendix 2
Chile Artisanal Mahimahi and Shark Longline Fishery
and Longline Swordfish Fishery:
Industry Practices and Attitudes towards Shark Depredation and Bycatch
Joanna Alfaro-Shigueto and Jeff Mangel, Pro Delphinus, Peru, prodelphinus@prodelphinus.org
Miguel Donoso, Instituto de Fomento Pesquero, Chile, mdonoso@ifop.cl
Twenty-two interviews with artisanal longliners for mahi mahi and
industrial swordfish fishermen were conducted in three fishing ports
in Chile from February to August 2006 (three from the swordfish
fishery and 19 from the artisanal mahi mahi longline fleet). Of the
artisanal fishermen, 2 were vessel owners, 10 were captains and 7 were
crewmembers. Average years of fishing were 37.5 for owners, 20 for
captains and 18.5 for crew members. All three swordfish fishermen
interviewed were captains with an average of 11 years fishing.
Information on the longline fishery was obtained from the
publications of the Servicio Nacional de Pesca (SERNAPESCA),
the Instituto de Fomento Pesquero (IFOP) and from the Food and
Agricultural Organization (FAO) publications that make reference
to Chilean fisheries and the FAO Fish Stats program. Information
on the regulations was obtained from the Subsecretaría de Pesca
(SUBPESCA).
Chile is divided in 12 geographic and political regions (I-XII). To
promote decentralization, each of these Regions has regulations and
quotas for each fishery. In northern Chile the artisanal longline has a
shark fishery similar to the Peruvian shark fisheries. For the purpose
of this study we conducted the surveys in this area during the mahi
mahi season, where sharks are taken as bycatch, and also conducted
the surveys of the industrial swordfish fishery, where sharks are also
taken as bycatch.
A2.1. Artisanal Longline Fishery Characteristics
Chilean legislation defines the artisanal fishery as an operation run by
individuals (fisherman, captain, vessel owner or crew) or industries
registered as such and using an artisanal vessel. An artisanal vessel
should be registered in that category, and has a maximum length of
18 meters and a maximum weight of 50 tons (Ley General de Pesca
y Acuicultura, 1991). There are about 131 vessels registered for this
fishery (Barria et al., 2006).
The artisanal fishery for mahi mahi (Coryphaena hippurus) operates
during the austral summer and for sharks throughout the year. There
are slight variations in fishing methods from vessel to vessel in the
artisanal longline fleet.
The use of longlines by the artisanal fleet to target sharks is only
authorized by the government to occur along Chile’s northern coast
from Region I to Region III (Diario Oficial, 2002). The main ports in
these Regions are Arica, Iquique, Tocopilla, Antofagasta and Caldera
(Barria et al., 2006). Sharks may be taken throughout the year, but
during certain seasons, when mahi mahi is more available and has
a higher value, the fleet tends to target mahi mahi. During the mahi
mahi season, vessels only land sharks that are caught during the trips
last sets and only if space is available on the vessel. If availability of
sharks is good, blue sharks are usually discarded because the price
for mako sharks is higher.
Captures of mahi mahi in these three regions account for 70% of
total landings of the species for the country. Forty seven percent of
the country total is captured in Region I (Arica and Iquique ports)
(SERNAPESCA, 2006).
A2.2. The Industrial and Artisanal Swordfish Fishery
The industrial swordfish fishery‘s main target is the swordfish
(Xiphius gladius), but other species are also captured and retained
(Fig. A2.1). This fishery includes 16 longline vessels operated from
Coquimbo and Valparaiso (for administrative purposes, ten of these
vessels are registered as industrial while the remain 6 are listed as
artisanal). This is a seasonal fishery that operates mainly from March
to December. Length of vessels range from 16.6 - 42.2 m. Storage
capacity ranges between 40 to 374 m 3 (Barria et al., 2006).
This longline fishery operates mainly from 16°S - 40°S and 78°W -
108°W. The fleet is active primarily from March to September, but
some sets are also performed through December. The principal
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