Dear MARMAMERS, I am pleased to announce the following publication:
Iriarte, V. & Marmontel, M. (2013). Insights on the use of dolphins (boto, Inia geoffrensis and tucuxi, Sotalia fluviatilis) for bait in the piracatinga (Calophysus macropterus) fishery in the western Brazilian Amazon. J. Cet. Res. Manage. 13(2):163-173.
ABSTRACT: In the Amazon Basin the use of the pink dolphin or
boto (Inia geoffrensis) for bait in
the piracatinga (Calophysus macropterus)
fishery was first detected in the year 2000. Since then, this artisanal fishery
has become more prevalent as it requires only a few hours of work per night and
provides immediate cash earnings. It is thus an attractive addition to (or
replacement for) traditional fishing. Previous reports have noted the use of
botos as bait, but stated that the most common bait used are caimans (Melanosuchus niger, Caiman crocodilus). Estimates of the number of dolphins killed
based on fish landings have been proposed and an apparent decrease in
sighting/survival of an artificially-marked boto population was observed. Although
stocks/population estimates, trends, and actual numbers of hunted dolphins are
unknown, the conservation impacts of this activity are of concern. Between
October 2010 and November 2011, research was conducted within an area with serious
conflicts between dolphins and fishermen as well as intense fishing for
piracatinga, i.e. in the lower Japurá River, on the border with the Mamirauá
and Amană Sustainable Development Reserves, where both boto and tucuxi (Sotalia fluviatilis) are used for bait.
One-hundred and fifty-seven monitoring surveys were carried out in eight key
communities, confirming 114 piracatinga fishing events through direct
monitoring and incognito surveys of fishing gear (gaiolas). Empirical evidence of the activity in gaiolas comprised pieces of bait,
carcass remains, piracatinga provoked vomits and dolphin fished carcasses. Of
those, 31.2% (n=35) involved cetacean
bait (91.4% I.
geoffrensis, 8.58% S. fluviatilis), 68.7% (n=77)
caiman bait (96% M. niger, 4%
C. crocodilus), and two fishing events used both types. These
percentages may be higher/lower in other areas within and outside the Reserves.
Given the increasing trend of the piracatinga fishery, the authors believe that
precautionary measures for the conservation of Amazonian dolphins are urgently
needed. Development of practical short-term solutions (e.g. offal-baited fish
traps) and multispecies management together with law enforcement, incentives,
and educational programmes could allow the future transition of riverine communities
from the piracatinga fishery to sustainable, higher income activities.
KEY WORDS: BOTO;
TUCUXI; DIRECT CAPTURE; FISHERIES; CONSERVATION; MANAGEMENT; SUSTAINABILITY;
REGULATIONS
Pdf copies can be requested to verorcinus@gmail.com
Sincerely,
Verónica
--
Verónica Iriarte, MSc
Calles 25 y 26
Edif. Club del Mar ss104
CP: 20100
Punta del Este
Uruguay