4.2 Methodology The herpetofauna surveys were conducted over seven days (26
September to 2
October 2013) in various sites within the Greater Delaikoro Area, in particular the
upland and lowland forests of Mt. Delaikoro, Mt. Sorolevu and the Waisali Reserve
(Figure 12). The survey targeted ideal herpetofauna habitat and methods employed
depended on the weather and logistics (Appendix 9).
Field Assessment Weather conditions dictated the number of days, type of traps and survey methods
conducted, and these are summarized in Appendix 9.
Habitat Assessment The objective of the expedition was to record all herpetofauna species captured
and/or observed within the study site. For this reason, all potential habitats within
good forest cover and outside of the forest were surveyed. The study area generally
had ideal herpetofauna habitats: riparian vegetation, ridge forest, forest floor cover
of leaf litter and rotting wood, and trees with dense epiphyte cover. Systematically,
the survey targeted a ridge habitat, riparian forest habitat and lowland forest habitat,
closely following the vegetation and entomology sampling areas. A total of 44 sites
were surveyed employing the methods described below.
Diurnal and nocturnal herpetofauna surveys There are several accepted methods for herpetofauna surveys that generally fall
under two categories: opportunistic diurnal and nocturnal searches and trapping,
and standardized nocturnal and diurnal searches and trapping. A summary of the
methods used in this survey is given in Appendix 9.
Herpetofauna surveys in Fiji have generally been opportunistic, but their methods
standardized to allow for comparison between sites. Long term, standardized
herpetofauna monitoring plots exist on Viti Levu: the Sovi Basin Conservation Area
and the Wabu Forest Reserve are limited to nocturnal frog searches. Because of the
cryptic and heliophilic nature of Fiji’s reptiles; and Fiji’s climate, the visual survey
and trap methods are used, albeit limited by weather conditions.
The herpetofauna surveys in the Greater Delaikoro Area consisted of three
techniques but were constrained by rain. These are described below.
Standardized sticky trap transects whereby sticky mouse traps (Masterline®) were
laid out at intervals along a transect. Each station was designated a station number
(1-10) with a cluster of three traps per station for three placements to represent local
habitat structure at each location (tree, log and ground). Transects were laid out
along identified ideal habitats e.g. ridge tops and along river banks/riparian
vegetation. Leaf litter cover, canopy cover and undergrowth were all recorded. Left
overnight (if possible), traps were checked regularly for captured specimens. These
traps target both terrestrial and arboreal species.
Standardized (time constrained) nocturnal visual encounter surveys (2 hours) in
ideal habitats were used, since frogs and geckoes are active and more visible at
night. This method gives an encounter rate for comparison with other surveys
within Fiji. Search efforts with a minimum of two observers at any one time targeted
streams, adjacent banks/ flood plains and ridge tops.
Opportunistic Visual Encounter Surveys outside of the standardized searches
allowed for a record of presence/absence of herpetofauna. Skinks are more likely to
be seen during the day, particularly during hot and sunny conditions. Opportunistic
diurnal surveys were conducted along trails en route to the camp site, vegetation
plots, along stream edges, and in forest habitats surveyed by other survey teams in
the expedition. Search efforts targeted potential skink habitat and sunbathing spots,
and frog and snake diurnal retreat sites. Diurnal surveys began at 9am and ended at
3pm on each of the survey days. The team had a minimum of two searchers at any
Environmental variables such as air temperature, water temperature, weather
conditions (rain/fine) and cloud cover (%) were taken at the beginning and end of
each nocturnal survey. Habitat characteristics and other basic ecological and
biological information of herpetofauna found were recorded. Observations on
possible threats to herpetofauna species and populations were also noted.
Geographic coordinates of survey sites were captured using the Thales Mobile
Mapper Pro Navigator and Garmin GPSmap 60CSx.
4.3 Results Average air temperatures recorded for the surveys were 23.5
C (day time) and
C (night time); average water temperature was 17.3
C at night. Out of the eight
days, there were four days of good sunshine, and six in which cloud cover was
Based on the current knowledge of herpetofauna on Vanua Levu there are a total of
21 species recorded from the island, of which thirteen have been documented from
within the Delaikoro Area (Morrison, 2003; Morrison et al., 2004).
In total eight species were encountered over the course of the survey, in 34 of the 44
sites surveyed. Four of the species encountered are endemic: Emoia concolor, Lepidodactylus manni (Figure 13), Platymantis vitianus (Figure 14) and P. vitiensis (Figure 15 and Figure 16).
Figure 13: Lepidodactylus manni (Photo: Noa Moko)
Figure 14: Platymantis vitianus (Photo: Noa Moko)
Figure 15: Platymantis vitiensis (Noa Moko) Figure 16: Platymantis vitiensis eggs (Photo: Apaitia Liga) Three others are native: Emoia cyanura (Figure 17),Gehyra oceanica (Figure 18), and
Nactus pelagicus, and there was one invasive species also recorded (Bufo marinus).
These findings were the result of over fourteen man-hours of diurnal survey, 436
hours of sticky trapping and six man-hours of nocturnal surveys.
One species was reported to occur by local villagers: the native Pacific boa (Candoia bibroni), but was not encountered during the expedition.
Figure 17: Emoia cyanura (Photo: Noa Moko)
Figure 18: Gehyra oceanica (Photo: Nunia Thomas) Herpetofauna were observed on all the survey days through the methods employed.
The majority of the species were encountered during opportunistic surveys (4
species); with lower encounter rates for the sticky traps (2 species), and standard
diurnal (1 species) and nocturnal surveys (2 species).
Threats to herpetofauna were also documented. The presence of rats was evident on
one sticky trap (Mt Delaikoro). Additionally the mongoose was observed, and cat
scat recorded at high elevations in the Mt. Sorolevu area.
4.4 Discussion This report contributes to the little known terrestrial herpetofauna of Vanua Levu,
and more specifically the Greater Delaikoro Area. Despite the impact of introduced
mammals on Fiji’s terrestrial herpetofauna the widely documented presence of the
Fiji ground frog on Vanua Levu is interesting. Two species whose extirpation has
been attributed to introduced mammalian predators such as feral cats, feral pigs and
the mongoose, and were not encountered on this survey area are the two large
terrestrial skinks Emoia trossular and E. nigra.
The low encounter rates and low diversity of herpetofauna in the study sites do not
necessarily mean an absence of the species. Low encounter rates of heliophilic
species are not uncommon in Fiji’s rainforests and are typical globally in rainforest
habitats (Ribeiro-Junior et al., 2006; Ribeiro-Junior et al., 2008). There are efforts being
made to develop better quantitative survey methods for forest dwelling
Sites to target for the establishment of long-term monitoring plots should ideally be
adjacent to the vegetation sample plots, because of the dependence of native
herpetofauna on the health of the forest.
4.5 Recommendations Considering that baseline survey within the Greater Delaikoro Area has now been
conducted, the best option available will be to build on this by conducting
subsequent surveys and standardizing the survey techniques especially for the
sticky traps and frog surveys, carrying them out over different seasons and assessing
species densities. Any future changes in terms of species presence/absence and
density will be an indication of the status of the habitat and forest. It is
recommended that these intensive and dedicated surveys focus on a particular area
or along standard transects. It is also recommended that tree climbing techniques be
used to enable better capture rates of cryptic arboreal skinks and gecko species.
5 Freshwater Fishes Lekima Copeland and Kinikoto Mailautoka
5.1 Introduction The effective conservation of Fiji’s freshwater fish requires accurate understanding
of the distribution, taxonomic composition, endemicity, and local richness of species
assemblages across the Fiji archipelago. This is particularly true when on a global
scale the freshwater fishes of Fiji have been recently recognised in terms of endemic
species per unit land area (Abell et al., 2008). The freshwater fishes of Fiji have only
been extensively studied in the last decade by various researchers that have
discovered species new to science and elucidated some of the various factors
affecting these insular fish assemblages (Jenkins and Boseto, 2005; Boseto, 2006;
Boseto and Jenkins, 2006; Jenkins, 2009; Jenkins and Mailautoka, 2010; Larson, 2010;
Jenkins and Jupiter, 2011; Copeland, 2013). The oceanic islands of the Pacific are
distinct from continental land masses in that they have developed unique freshwater
fish assemblages that have important ecological linkages between marine and
freshwater environments (McDowall, 2008). The prospection of this area is
important to improve our knowledge of freshwater fish distribution in Fiji.
5.2 Methodology Due to the remoteness of the study areas, several methods of gathering data were
used. Unfortunately, the breakdown of the electrofisher meant that abundance data
could not be gathered. The field methods described here were designed to enable the
most comprehensive documentation of fishes present in the tributaries originating
from the Delaikoro mountain range. A portable Global Positioning System (Garmin
eTrex 20) was used to take the position and altitude of the sampling sites. A map of
the study area and several pictures of the locations sampled are provided.
Physiochemical parameters Before fishing commenced, water quality parameters were recorded to minimise
disturbances to in-situ water quality characteristics. Temperature, pH, conductivity,
salinity and dissolved oxygen were measured using a commercial handheld GPS
Aquameter and AP-1000 Aquaprobe.
In-stream fish sampling The beach seine (3 m x 2 m, 1 mm mesh) was set and held by two people. Several
metres upstream one person kicked and dislodged rubble to enable the collection of
bottom-dwelling fish. This was done for about an hour, over approximately a 100 m
stretch of stream. Snorkeling was also undertaken in streams sampled and visual
observations were made from stream bank, as some species of the gobies are easily
distinguishable due to their bright colours.
Preservation Voucher specimens were collected, fixed in a 10% formalin solution and transferred
to 70% ethanol solution after five days of fixation. Voucher specimens were
deposited at the University of the South Pacific marine collection.
5.3 Results and discussion Species richness Overall a total of eighteen species of fish from six families were directly observed or
collected (Table 2). The inability to use the electrofisher contributed to the low
species number but even taking that into account Fiji’s fish fauna is impoverished in
comparison to Melanesian countries to the west, such as Papua New Guinea. The
community structure of fishes is of the general composition expected within Indo-
West Pacific high islands, in that species numbers are relatively low and are
characterized by amphidromous species (pelagic lifecycle). The amphidromous life
history results in most of these species being found throughout Oceania.
Figure 19: Location of freshwater fish sampling sites
Table 2: Species checklist for the thirteen sites 1 surveyed (*=endemic species) Family Species 1
Four of the species collected are endemic to Fiji; the two described gobies Redigobius lekutu and R. leveri and the undescribed gobies Stiphodon n. sp. 1 and Stiphodon n. sp.
2. Three invasive species were collected and observed during the survey. These were
the guppy, Poecilia reticulata and two species of tilapia, Oreochromis niloticus and O. mossambicus.
The dominant element of the fauna is the gobioid fishes, mainly members of
Gobiidae and Eleotridae. This assemblage accounts for 61% of the overall fauna.
Members of the gobiid subfamily Sicydiinae (containing Sicyopterus, Sicyopus and
Stiphodon) are especially prominent in clear, rocky streams, which constitute the
1. Nasealevu Village 2. Upper Dreketi 3. Upper Doguru (1) 4. Upper Doguru (2) 5. Doguru village
6. Qaraloaloa stream 7. Waicacuru stream 8. Suweni stream 9. Waisali stream 10. Camp site upper 11.
Camp site 12. Camp site lower 13. Wai Koroalau.
dominant aquatic habitat in the interior of the islands. The depauperate species
richness is a feature of insular systems of Oceania where this attenuation in species
richness with increase in altitude has been documented by Jenkins & Jupiter (2011).
The highlight of the survey was the discovery of a native goby Lentipes kaaea on
Vanua Levu. This specimen had only been found previously on the island of
Taveuni. A species from the same genus, Lentipes concolor (endemic to Hawaii), is
renowned for its ability to surmount waterfalls over 100 m high. The discovery of
this species and also two undescribed gobies in the genus Stiphodon showcases the
pristine water quality in this catchment. Amphidromous stream-cling-gobies of the
genus Stiphodon comprise an important component of the fish communities in
insular streams of tropical Indo-Pacific high islands.
Most of the non-gobioid fishes are basically itinerant marine forms restricted to the
lower reaches of freshwater streams. The first significant waterfall usually forms a
barrier to their upstream dispersal (Figure 21).
Figure 21: A waterfall in Cakaudrove province marks the upstream limit for itinerant fishes such as Kuhlia rupestris and K. marginata. Water Quality Results of the on-site measurements are tabulated in Appendix 11. Temperature at
the sites was between 19.7°C and 20.4°C. Dissolved oxygen levels were fairly high,
above 8 mg/l, making it readily available for fish at the six stations sampled.
Conductivity at all sites ranged from 0.047–0.084
S which is well within the suitable
habitat range for stream fish. Turbidity was very low at all sites (<10 NTU), and the
bottom was visible at all the stations.
5.4 Conclusion and recommendations The proper management and use of aquatic resources in streams originating from
the Delaikoro range entails a holistic approach due to the life-history strategies
employed by aquatic fauna that traverse different habitats throughout their life. It is
true that management must begin at the catchment level; however, it goes hand in
hand with the protection of marine and coastal habitats such as reefs, seagrass
meadows, mangrove habitats, including the terminal reaches of rivers and streams.
This survey found two endemic gobies (Redigobius lekutu and R. leveri) and two
undescribed gobies from the genus Stiphodon. The discovery of the sicydiine goby
Lentipes kaaea highlights the importance of carrying out further work on the island of
Vanua Levu. This goby has only been collected on the island of Taveuni and this is
the first record for Vanua Levu.
The following are suggestions for the proper management and conservation of
aquatic fauna in the Delaikoro mountain range:
The first priority is protection of the catchment areas originating from the
Delaikoro mountain range. The headwaters should be set up as a protected
area with a complete ban on slash-and-burn techniques around the
Secondly, the other major issue identified is the importance of restoring buffer
zones around mid-reach sites. This will also require the proper education of
farmers (landowners) on establishing farms near rivers, and the importance of
a buffer width and restricting livestock access across streams.
Further aquatic biodiversity research is needed in the headwaters of the
Delaikoro range especially for streams draining into Cakaudrove province.