Proceedings of the International Cyanide Detection Testing Workshop

10–90% following exposure to cyanide but
recovered to pre-exposure levels within 1–2
hours after transfer to clean seawater. These
researchers also observed that corals died
after exposure of cyanide at the highest doses
used by fi sh collectors. After medium doses,
the corals lost their symbiotic algae resulting
in discoloration or bleaching. After exposure
to the lowest doses they lost zooxanthellae but
not in suffi cient numbers to cause noticeable
discoloration.
Cervino (Cervino, Hayes et al., 2003) also
found that cyanide exposure can be lethal to
corals. Cervino (Cervino, Hayes et al., 2003)
exposed a variety of coral and anemone species
in the lab and in the fi eld to the following
concentrations of cyanide solution for 1-2
minutes: 50, 100, 300, and 600 mg/l. Upon
exposure, corals and anemones immediately
retracted their tentacles and mesenterial
fi laments, and discharged mucus containing
zooxanthellae. Gel electrophoreses techniques
found changes in protein expression in both
zooxanthellae and host tissue. Both corals
and anemones showed an immediate increase
in mitotic cell division of their zooxenthellae,
and a decrease in zooxanthellae density. In
contrast, zooxanthellae cell division and
density remained constant in controls. Other
changes included gastrodermal disruption,
mesogleal degradation, and increased mucus
in coral tissues. Zooxanthellae showed
pigment loss, swelling, and deformation.
Cervino (Cervino, Hayes et al., 2003) reported
mortality occurred at all exposure levels, and
concluded that exposure to cyanide causes
mortality to corals and anemones, even when
applied at lower levels than those used by
fi sh collectors. Cervino (Cervino, Hayes et
al., 2003) also stated that even brief exposure
to cyanide caused slow-acting and long-term
damage to corals and their zooxanthellae.
99
Jones et al. (Jones, Kildea et al., 1999) measured
the effects of cyanide on coral photosynthesis
through a series of experiments conducted in
the fi eld. These measurements were made in
situ and in real time using a submersible pulse
amplitude modulation (PAM) fl uorometer.
In Stylophora pistillata, exposure to cyanide
resulted in an almost complete cessation in
photosynthetic electron transport rate (Jones,
Kildea et al., 1999).
Jones et al. (Jones, Kildea et al., 1999) concluded
that, based on these studies, cyanide-induced
bleaching has been documented in fi ve species
of corals. The species studied represent a
variety of coral types, including encrusting,
massive, and branching growth forms.
This experimental evidence of bleaching is
supported by observations (Erdman and Pet-
Soede, 1996) who report bleached and dead
corals surrounding holes or recesses on reefs
where cyanide fi shing had occurred (Jones,
Kildea et al., 1999).
Cyanide Fishing in Context
This document outlines that exposure to
cyanide presents a temporary stress on fi sh,
corals, and surrounding organisms. Overall,
the literature suggests that these impacts
have cumulative, potentially long-lasting
effects; however they are diffi cult to quantify.
Conservation and Community Investment
Forum (CCIF) presented one estimate of
overall reef-degrading capacity of the cyanide
fi shery for food fi sh. In Indonesia the loss of
live coral cover is approximately 0.052 m 2 per
100 m 2 of reef per year (Conservation and
Community Investment Forum, 2001).
It is important to include the work of some
researchers that state that the aggregate
impact of cyanide fi shing is minimal. Mouse
et al. (Mouse, Pet-Soede et al., 2000) state
that the toxicity of cyanide to corals under
experimental conditions is, in itself, no proof