Dolphins, Porpoises, and Whales - IUCN

Figure 25. A young boto, killed in a gillnet, is carried up the bank
so that it can be photographed and measured. Such incidental
mortality is widespread and thus a growing concern among conservationists.
In most areas of the Amazon and Orinoco systems,
botos are not hunted, but their attraction to fishing activities
often makes them a nuisance to fishermen and increases their
vulnerability to accidental entanglement (San Martin, Tipishca
de Samiria, Peru, 28 July 1993).
right whale studies in which various researchers (as well as
amateur photographers), often from different countries,
have contributed to a common pool of high-quality photographs
that are curated and archived in a central repository
for collaborative use. Joint authorship of publications
would encourage wide participation. The objective would
be to establish such a repository and begin compilation of
a catalogue of known individuals. A standard protocol
for tissue collection and preservation should be established.
This project is intended to include both South
American species (Inia geoffrensis and Sotalia fluviatilis).
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Franciscana
In addition to the two projects explicitly dealing only with
the franciscana, below, two regional projects (32 and 40)
relate largely to this species.
Project 20
Differentiate stocks of franciscanas
Although the state of knowledge on the biology of this
heavily-exploited South American endemic species has
improved greatly during the past decade (see contributions
in Perrin et al. 1989a, Monzon and Corcuera 1991,
Crespo 1994, IWC in press a), there is still uncertainty
about stock structure. Pinedo (1991) described two geographical
forms of franciscana, one found to the north and
one to the south of Santa Catarina, Brazil. It was agreed
at the 1992 meeting in Buenos Aires that stock analysis
was a high priority for this species and that various
approaches should be used, including molecular biology
techniques, osteological comparisons, and differences in
growth and reproductive patterns, parasite faunas, and
contaminant loads. Also, it was pointed out that surveys
of the area in Brazil between the states of Santa Catarina
and Rio Grande do Sul would be useful for determining
whether the species' distribution is continuous or discontinuous
in this area.
It is expected that this project will consist of independent
subprojects by various researchers. Ideally, investigators
using a given approach will have access to a
pooled sample of materials, with appropriate credit given
to all contributors in any resultant reports or publications.
For example, collaborative work on pollutant levels and
parasites is already underway at the universities of
Barcelona and Valencia in Spain, and it would be beneficial
if the samples being used for these studies were
augmented by material from areas in addition to
Necochea, Argentina. Once a sufficient amount of work
has been completed using several different methods, it
may be appropriate to convene a small working group to
compare and evaluate results, and to plan any additional
work that is considered necessary.
Project 21
Design and implement surveys to estimate population
size of franciscanas ("old" Project 9)
There is a continuing need for reliable information on
abundance of franciscanas. "Old" Project 9 called for a
meeting of key researchers to select a survey method and
site, and for a "pilot survey" to be carried out as soon as
possible thereafter. At Buenos Aires in 1992 it was agreed
that the best site for a preliminary study would be near
Valizas and Cabo Polonio, Uruguay, where the catches per
unit effort in the shark fishery have suggested a locally
high density of franciscanas. It was also agreed that a