Vol 3 Land Resource Inventory Report - Department of Environment ...

Summary Report to Fiji Government Departments of Environment, Forestry & Agriculture, July 2010
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The Fiji Islands however, does have at least 18 introduced species with variable risk levels
to agricultural productivity, biodiversity loss or human and livestock health (Brodie & Barker,
in review). Based on a comparison of our current observations (Mila et al. 2010; Brodie &
Copeland, submitted; Brodie, in press; Brodie, unpublished data) and past observations
(Solem, 1978; Barker, 1979; Haynes 1998) some introduced species e.g. Bradybaena
similaris (Rang, 1831) and Quantula striata (Gray 1834) have obviously increased in
abundance, at least on the largest island of Viti Levu.
However, the most worrying “new” snail introduction absent in the reports by Solem (1978)
and Haynes (1998) is the presence and very obvious increase in abundance and distribution
of the “semi-slug” Parmarion martensi Simroth 1893 (Figure 1). First officially reported in Fiji
by Barker (2005), but known from southeast Viti Levu from as early as 1979 this species is
now numerous and widespread in areas of human habitation, and alarmingly has also
recently been found (Brodie, in press; Brodie & Copeland, submitted; Brodie unpublished
data) in three of Fiji’s high priority forest areas highlighted by Olsen et al. (2009).
In addition to its newly reported highly invasive status in Fiji by Brodie & Barker (in review) P.
martensi is also considered by these authors as a potential high-risk vector in Fiji for the rat
lung worm Angiostrongylus cantonensis (Chen, 1935). This parasitic worm is associated with
eosinophilic meningitis in humans. Angiostrongylus cantonensis and eosinophilic meningitis
are already established in Fiji (Alicata 1962, Uchikawa et al. 1984, Sano et al. 1987, Paine et
al. 1994) and is commonly reported as associated with less “risky” invasive snail species
such as the “leatherleaf” slug Laevicaulis alte (Férussac, 1822).
However, recent discovery by the first author of a living Bradybaena similaris (Rang, 1831) in
salad sold at a popular BBQ take-away stand in Suva City (Figure 2) highlights the reality of
the potential for future health problems, particularly when many families, communities and
tourism facilities are being actively encouraged to grow their own salad vegetables. As
recently highlighted by senior Koronivia Research Station staff (pers. comm.), there is a
strong need to investigate the life history characteristics and parasite infection levels of all
introduced land snail species in Fiji.
Priority Groups for Conservation & Biodiversity Assessment
Fiji’s 167 endemic land snail species are very diverse, spanning 19 families (Table 1). Two
groups in particular stand out as achievable species-level conservation priorities. These are:
(a) Fiji’s 12 endemic species of the taxon Placostylus, eight of which are found on only one
island each in the Fiji group (see Figure 3 for an idea of what members of this genus look
like); and (b) members of the taxon Trochomorpha which according to Barker (2005) has at
least 18 species endemic to Fiji (see Figure 4 for an example of this genus).
Besides the above groups, two additional groups are highlighted in the literature as
extinction prone on islands because of their vulnerability to introduced predators – these are
the microsnails of the family Endodontidae and members of the family Rhytididae. The
endemic members of the supralittoral snails (families Ellobiidae and Truncatellidae) should
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