This is the ﬁ nal version of the article that is
published ahead of the print and online issue
Insights into the feeding ecology of the Seychelles Black Parrot Coracopsis
barklyi using two monitoring approaches
*, Heather Richards
, Terence Payet
, Pascal Villard
, Matthias Waltert
and Nancy Bunbury
Seychelles Islands Foundation, Victoria, Mahé, Seychelles
Conservation Biology, Workgroup on Endangered Species, Georg-August Universität Göttingen, Göttingen, Germany
* Corresponding author, e-mail: firstname.lastname@example.org
Feeding ecology is an important factor for the survival of a species and knowledge of its parameters is
a prerequisite for successful conservation work. In this study we describe the feeding ecology of the endemic
Seychelles Black Parrot Coracopsis barklyi on Praslin, Seychelles, the only island on which this parrot is resident.
We compared two methods to evaluate feeding choices: incidental observations and feeding walks on 25 transects
in all habitat types. Black parrots fed on 46 different species, bringing the total number of known food plants to
53 species. They predominantly consumed endemic and native species (58% of observed feeding bouts), mainly
their fruit pulp (in 68% of feeding bouts), followed by buds (15%) and seeds (37%) with occasional observations
of leaves, bark and scale insects. The incidental method rendered many more observed bouts than the transect
approach and the ratios of consumed species differed between methods but the transect results are regarded
as more representative. The incidental method is not suitable for quantitative conclusions but complements the
transect method, providing information about rarely occurring feeding events.
Keywords: Coracopsis barklyi, feeding ecology, Indian Ocean, palm forest, parrots, Seychelles Black Parrot
Successful conservation depends inter alia on preservation of
feeding resources, since food availability influences popula-
tion numbers directly and indirectly via survival, mortality,
fitness, productivity and breeding success (Saunders et al.
1991; Jones 2004). Food preferences and foraging strate-
gies define species’ roles as pollinators, seed dispersers or
predators, and determine competitive relationships with other
species. Knowledge of identity and availability of feeding
resources as well as foraging location, timing and habits are
thus important prerequisites for conservation. Many conser-
vation projects collect data on feeding ecology, although
methods vary and usually have to balance feasibility with the
need to record sufficient feeding observations to draw conclu-
sions. Recording incidental observations produces many
observations with limited effort (Bollen and van Elsacker
2004; Ortiz-Catedral and Brunton 2009), but such observa-
tions, although providing insight into a species’ feeding
ecology, are typically not representative and do not allow
quantitative conclusions. Dedicated feeding transects permit
comparisons over time and, depending on the sampling
method, between areas (Pizo et al. 1995, Renton 2001).
The Seychelles Black Parrot Coracopsis barklyi breeds
only on the island of Praslin in the Seychelles, with a popula-
tion size of 520–900 birds (Reuleaux et al. 2013). Despite
its tiny population size and distribution, C. barklyi acts as a
flagship species for the rare palm forest habitat on Praslin,
particularly the UNESCO World Heritage site of the Vallée
de Mai. It is also the national bird and an avian cultural
icon of the Seychelles. The Seychelles Black Parrot’s
single island distribution makes it highly vulnerable to
stochastic effects such as forest fires, disease outbreaks
and climate change, which, among other impacts, may alter
plant phenology cycles. Breeding is seasonal but does not
occur every year (Reuleaux et al. 2014), which is likely to
be linked to food availability. The fragility of the Seychelles
Black Parrot population prompted the development of
the Seychelles Black Parrot Action Plan (Rocamora and
Laboudallon 2009), which proposes conservation measures
and further research into areas including feeding ecology.
Seychelles Black Parrots are known to feed on a variety
of fruits and seeds of native and introduced plants (Gaymer
et al. 1969; Rocamora and Skerrett 2001; Walford 2008;
Rocamora and Laboudallon 2009), but observations have
been incidental and limited in time and area. The main
aims of this study were therefore to gain an objective
understanding of Seychelles Black Parrot feeding ecology,
assess the value of incidental feeding observations in small
population monitoring, and provide information for future
conservation efforts. To achieve these aims we applied
and compared two data collection methods—incidental
feeding observations and controlled-effort transects—to
determine specifically (1) which plant species and parts
are eaten by C. barklyi and to what extent and (2) whether
results from incidental feeding observations can be used as
a reliable indicator of the relative importance or preference
of food species.
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Materials and methods
The research was carried out on the island of Praslin in
the Seychelles archipelago in the Indian Ocean (Figure 1).
Praslin Island (4°19′ S 55°44′ E; 38 km
, 367 m highest
Seychelles islands and is located at 44 km north of the
largest granitic island Mahé. The climate is tropical with little
variation in monthly mean temperatures of 25–28 °C (Walsh
1984) or humidity (monthly mean 75–80%). Annual rainfall
from May to October and a wet season from December to
March (Walsh 1984).
Praslin Island’s population of c. 8 500 people is primarily
settled around the coast (National Bureau of Statistics
2013). The coastal plain is relatively wide and heavily
modified by humans for cultivation, residential areas,
tourism and infrastructure. Large areas of the island have
been damaged by fire and are covered by secondary
vegetation (Meuwly 2002). Hillsides are usually covered in
boulders and thick scrub vegetation, whereas hilltops are
often eroded bare soil. Only remnants of native palm forest
occur in the uplands; the largest of these is protected in
the Praslin National Park. Within the National Park lies the
Vallée de Mai (19.5 ha), which is dominated by the endemic
Coco de Mer palm Lodoicea maldivica and has been
protected as a UNESCO Natural World Heritage site since
1983 and managed by a public trust, the Seychelles Islands
Foundation (SIF), since 1989. This research was carried out
as part of a broader research programme on the Seychelles
Black Parrots run by SIF since 2008.
We used two methods to collect feeding data: incidental
feeding observations from October 2009 to August 2013,
and transects with controlled search effort during three
periods: January–April 2011, February–April 2012 and
March–August 2013. For logistical reasons the transect
survey period fell at the end of or after the breeding season
(November–February) every year. Weather during the study
period was typical for the seasons, but October 2011 and
January 2012 were unusually wet months.
Consumed plants were identified with binoculars and by
examining dropped food items (the latter required many
dropped items to be found and collected to distinguish
between accidentally dropped items and actively discarded
plant parts). The following parameters were recorded for all
feeding observations: time, location, observer, food plant
species, plant part(s) consumed, number of parrots feeding,
and duration of feeding bout. Following other studies we
counted feeding observations in bouts; a ‘feeding bout’
consists of at least one parrot feeding on one or more parts
of a certain species, without taking the number of parrots
or the time spent feeding in account (Pizo et al. 1995;
Renton 2001; Ragusa-Netto 2007). We also recorded the
‘parrot feeding time’ or ‘resource exploitation’ for each bout,
which is calculated from the number of feeding individ-
uals multiplied by the number of minutes spent feeding
(Kristosch and Marcondes-Machado 2001) and is measured
in parrots*feeding minutes. Although this measure is
intuitively more representative of the importance of food
resources, it is not widely used; most studies assume
that number of bouts reflects resource use. We used this
measure to check this assumption for our data.
Incidental feeding observations were not randomised,
were recorded regardless of time or location.
Due to the low density of parrots across most of
Praslin Island, transects were located in areas of high
parrot activity using results from a population survey
(Reuleaux et al. 2013). Twenty-five transects of c. 800 m
length were chosen in 13 locations with known parrot
activity and presence of fruiting trees. Habitat type
of the transects was determined in the field for each
100 m section using the following categories: (1) palm
forest (67–100% endemic palms, canopy height
30%); (2) mixed forest (any other forest
with canopy height
6 m, canopy cover 30%); (3) native
scrub (majority of plants native, canopy cover
6 m); and (4) cultivated/residen-
tial (residential areas, farmland and other land uses).
Transects were positioned to cover equal lengths of the
four habitat types. In 2011, 19 of the 25 transects were
surveyed and the ratio of habitat types for that year was
corrected by randomly excluding data from transect
sections of the over-represented habitat types.
Transects followed footpaths, firebreaks and roads
because difficult terrain did not allow walking off-track while
concentrating on detecting parrots. Due to the density
of the vegetation the visually surveyed area per walked
distance was limited and, in combination with the low
density of feeding parrots, it was necessary to include aural
detections in the survey. In 2011 each of the 19 transects
was walked four times, twice in the morning (06:00–10:30)
and twice in the late afternoon (15:30–18:30), during hours
of high C. barklyi activity (Reuleaux et al. 2013). With
increased knowledge of the parrots’ behaviour the methods
were improved in 2012 and 2013 by including two more
time slots in the middle of the day, to investigate potential
diurnal movements between habitat types, resulting in
four time slots at 06:00–09:30, 09:30–12:00, 12:00–15:30
and 15:30–18:30, which were all surveyed once on each
transect each year. Transects were not surveyed in
moderate or heavy rain or strong winds. Walking speed
was c. 1 km h
. Attempts to locate parrots heard within
this if necessary. If the parrot was not found within 5 min
the transect was resumed. Each feeding observation was
counted as one feeding bout, regardless of the number
of parrots. If the birds stopped feeding on one plant and
moved to a different species or a tree of the same species
20 m away, a new feeding bout started and was marked
as a second record for the same individual(s). Feeding
parrots were followed until they were lost. Non-feeding
parrots were abandoned after 3 min.
Between January and April 2011 both methods were
carried out in parallel by two different observers. Only these
data were used for comparison of the methods.
All means are presented
1 SD unless stated otherwise.
We used two data sets: transect data (bouts observed on all
transects) and incidental data (bouts observed incidentally).
All statements requiring representative sampling are based
on the transect data set. For comparison of the methods
we created two subsets: incidental feeding observation
data collected from January to April 2011 were compared
with the data collected from feeding transects during the
same period. We used a two-sided Fisher’s exact test with
simulated p-value (Monte Carlo simulation based on 2 000
replicates) to compare frequency of plant species in number
of feeding bouts between the two methods. To ensure that
samples from the feeding transect data were independent,
we used only the first bout of each individual and tree.
Pearson’s product-moment correlation with log-
transformed variables was used to confirm if the number of
feeding bouts reflects the parrots’ feeding time (or ‘resource
Statistical analysis was performed using R version 2.10.1
(R Development Core Team 2013) with packages ‘reshape’,
‘chron’ and ‘psych’ (Wickham 2007; James and Hornik
2013; Revelle 2013). Rarefaction and species accumulation
curves were produced using the ‘vegan’ package (Oksanen
et al. 2013) and the function ‘rarefaction’ (Jacobs 2009). A
Lomolino model was fitted to the food species accumulation
and used to calculate the asymptote for the number of food
species (Lomolino 2000; Tjørve 2003).
A total of 1 903 incidental feeding observations were
recorded between November 2009 and August 2013,
predominantly in the Vallée de Mai. Over the whole study
period the incidental method rendered more observations
than the transect approach (148). During our study 46 plant
species were observed to be eaten by C. barklyi, bringing
the total observed (including previous studies) to 53 plant
species from 43 genera and 28 families that have been
documented to be consumed by C. barklyi (Table 1). The
asymptote of a species accumulation curve produced by
a Lomolino model using all observations is 73.4 species.
Twelve of these food species were observed to be eaten
only once by parrots. Twelve of the consumed plant species
are endemic to Seychelles, 12 others are native and 29
have been introduced.
The transect method showed that the majority (58%) of
feeding bouts was on endemic and native plant species
(Figure 2). Endemic palm species accounted for almost
one-quarter of parrot feeding bouts and Dillenia ferruginea,
a widespread endemic broadleaf, was the most consumed
Parrots were observed feeding on fruits, buds, seeds,
flowers, leaf petioles, bark and scale insects. Fruits were
targeted in 68% of the observations, buds in 15%, seeds
in 38%, and flowers, leaves, bark and scale insects were
each consumed in
1% of observations. Percentage of
fruits consumed was higher on endemics (81% on palms,
79% on other endemics) than on introduced species (61%;
3.03; Tukey HSD, p adj 0.045). Fruits and seeds
were eaten ripe (29%) or unripe (19%), while ripeness
stage remained unknown in 52% of feeding bouts. Food
processing habits were particularly notable on endemic
palm fruit as little substance appeared to be consumed: for
example, unripe palm fruit (Phoenicophorium borsigianum
and Nephrosperma vanhoutteanum) before seed develop-
ment were picked, punctured and then dropped; after picking
2, 4, 5
Bd, Fl, Fr(rp)
Bd, Fl, Si
Fr(ur,rp),Sd, Bd, Lf
2, 4, 5
Fr (ur), Lf, Bd
Fr(ur,rp), Bd, Sd
Big leaf mahogany
West Indies mahogany
Fr, Sd, Bd
1, 2, 3,4,5,5
Fr, Sd, Bd, Fl
Unidentified exotic palm
Seychelles stilt palm
Fr, Fl, Bd
Lf, Bd, Fr(ur,rp)
endemic to Seychelles,
native to Seychelles, I introduced to Seychelles), part eaten (Fr fruit, ur unripe, rp ripe, bd bud, sd seed, lf leaf [usually only
scale insect from leaf, fl flower), and source (1 Gaymer et al. 1969, 2 Evans 1979, 3 Walford 2008, 4 Rocamora
and Laboudallon 2009, 5
Downloaded by [Anna Reuleaux] at 01:52 01 September 2014
ripe fruit, parrots would first extract and drop the seed before
well. Dropped fruit parts did not visibly lack any flesh.
Among the food items, scale insects (Coccoidea), which
the parrots scraped from leaves of Calophyllum inophyllum
and Phyllanthus acidus, were the most unusual observa-
tions. This is the only invertebrate documented to be
consumed by C. barklyi.
Larger exotic fruit targeted for its seeds (e.g. Averrhoa
half the seeds had been extracted. Many fruits with a single
bite mark were found underneath parrot feeding trees.
Mangifera indica fruits were shared by several parrots.
Average group size during feeding transects was 2.34
1.73 (range: 1–9; 13 individuals was the maximum group
bouts lasted 529
505 s (range: 20–2 849 s) and each
one comprised 26.0
48.9 parrot*feeding minutes (range:
11.9). The results from feeding bouts
and parrots feeding time (parrot*feeding minutes) were
strongly correlated (r(27)
0.77, p 0.00001), indicating
that it is legitimate to use number of bouts as an estimate
for the extent to which a resource is used.
Despite equal sampling effort of transects in all habitat
types, most feeding bouts were in palm forest (32%) and
cultivated/residential areas (39%), followed by mixed forest
(18%) and native scrub (11%). Food species and the
proportion of endemics consumed depended on habitat
type (Fisher’s exact test: p
0.001 and p 0.001, respec-
tively), with more endemics consumed in palm forest (82%)
and native scrub (88%) than in mixed forest (52%) and
cultivated/residential areas (9%). The share of endemic
palms among the food plants was much higher in palm
forest (45%) and much lower in cultivated/residential areas
(2%) than the other habitats.
The transect data show that observed feeding bouts were
equally likely at all times of the day when pooling all habitats
3.73, df 3, p 0.29). The likelihood of observations
over the day, however, was influenced by habitat (Fisher’s
exact test: p
0.003): in palm forest, feeding observations
occurred more often in the early morning and late afternoon
than expected from the search effort, whereas in the middle
of the day fewer bouts were observed (
0.021). The other habitat types did not show significant
differences to the expected daytime distribution.
Comparison between incidental and transect methods
Between January and April 2011, the period when both
methods were carried out in parallel, 311 incidental and
53 transect observations were collected. This corresponds
to 17 and 19 different food species, and 1 264 and 385
parrot*feeding minutes, respectively.
The proportions of plant species in the feeding bouts
differed between the two methods (Fisher’s exact test:
0.001; Figure 3). After removal of all observations
obtained in the Vallée de Mai car park (55), which was
walked past several times a day, the results from the two
methods still differed (p
Over the four-year study period, species accumulation
and rarefaction curves show that the incidental data set
comes closer to an asymptote of total number of consumed
species (Figure 4).
The large number of plant species and parts on the list of
orous-granivorous-herbivorous feeder, similar to several
other parrot species (Galetti 1993; Vaughan et al. 2006;
Contreras-González et al. 2009). Since 12 of the plant
species were only observed to be eaten once it is likely that
further research will reveal more infrequently consumed
coverage of all habitat types; dark fill: endemic palm species; medium grey: other endemic and native species; light grey: introduced species
species, which is congruent with the asymptote of the
species observed in this study is larger than in earlier
studies of Seychelles Black Parrots (Gaymer et al. 1969;
Evans 1979; Walford 2008; Rocamora and Laboudallon
2009) as expected with the longer survey period and
substantial search effort. Bollen and van Elsacker (2004)
found a similar number of species (40) to be consumed by
C. nigra in Madagascar.
The Black Parrot’s assumed tolerance for high tannin
contents, known from C. nigra in south-eastern Madagascar
(Bollen and van Elsacker 2004), makes them independent
of ripeness in most fruits. This is an advantage for avoiding
competition with other frugivores and granivores that rely
on ripe fruit. According to the definition by Hulme and
Benkman (2002), the Black Parrot should be considered
a pre-dispersal seed predator for most species as it takes
fruits before they are ripe and the seeds are either eaten
and digested or destroyed. This is true for all regularly
consumed introduced species. The consumption of ripe
endemic palm fruit is a different case as the seeds are
viable and are not consumed but usually dropped directly
underneath the tree, making the parrot an inefficient seed
disperser. The Black Parrot has potential to disperse seeds
of the endemic Verschaffeltia splendida, D. ferruginea and
Ficus lutea because the fruits are eaten when ripe and
occasionally carried before consumption; the seeds of the
latter two species are small and often stick to the bill.
The proportion of plant parts consumed in this study
differs from findings of C. nigra in Madagascar. Of the plant
species observed to be consumed there, 68% of bouts were
on seeds, 22% seeds and pulp, and 10% only pulp (Bollen
and van Elsacker 2004). The proportion of species eaten
for their seeds is much lower in our study. The vegetation in
south-eastern Madagascar is fundamentally different from
Praslin Island’s and the overlap in food species is minimal
(one). The low importance of seeds and in particular
endemic palm seeds in the diet of C. barklyi is notable. In
other parrot species, seeds often account for more than
half of consumed plant parts (Forshaw 1989; Galetti 1993;
Matuzak et al. 2008). Seeds have a high energy content
and their consumption increases foraging efficiency (Hulme
and Benkman 2002), so the fact that endemic palm seeds
passed through the parrots’ beaks but were then regularly
discarded instead of consumed is surprising. In Seychelles,
the fruit pulp of native plants is generally lower in energy
content than invasive species (Kueffer et al. 2009), which
may explain the parrot’s attraction to introduced species.
Inefficient foraging would explain food stress despite
year-round availability of most consumed food plants.
In Bollen and van Elsacker’s (2004) study of C. nigra,
flowers played a similarly minor role as in C. barklyi, whereas
Hampe (1989) described a shift from pure fruit consumption
to c. 80% flower consumption in the course of his three-week
study period in C. nigra in western Madagascar. Insectivory
in parrots is not a new observation (e.g. Forshaw 1989;
Figure 3: Percentage of total number of feeding bouts of each food
species observed in transects and incidental observation methods
(based on data from January–April 2011; n
53 [transects] and
curve (a) with increasing number of transects (exact method,
100 permutations), (b) rarefaction curves comparing number of
consumed species between methods of data collections and
(c) between habitats in the overall transect data set
OBSERVATIONS IN SUBSAMPLE
OBSERVATIONS IN SUBSAMPLE
Greene 1998; Renton 2001), including Poicephalus spp.
(2002) report that Orange-fronted Parakeets Cyanoramphus
Zealand also consume scale insects.
In contrast to the results of this study, Evans (1979)
concluded from his observations of parrot distribution
(concentrated at the Vallée de Mai) that the endemic palm
V. splendida was an important food source and could be
a crucial factor for parrot feeding and distribution. We
found no support for this claim. Only 2% of incidental
and less than 1% of transect feeding observations were
on V. splendida making it the least consumed of the four
endemic palm species in our study. Seasonality may play a
role; Evans’ (1979) study period in August falls in our least
surveyed period and 70% of our incidental observations
on V. splendida were between October and December,
when the fruits were ripe. Our data may underestimate the
importance of this species as a food item; however, it is
unlikely that a single species, which peaks in fruit produc-
tion at the same time as most other food species, and is
only moderately consumed when available, limits the distri-
bution on a small island such as Praslin, where parrots
travel half the island’s width regularly.
Despite covering a variety of habitats, the two species
most commonly consumed by C. barklyi, comprising
more than one-third of all observed feeding bouts, were
endemics: P. borsigianum and D. ferruginea are particularly
important due to their year-round high availability in most
habitats. Some native species (e.g. N. vanhoutteanum
and Paragenipa wrightii) seem to be preferred but are
relatively rare and bear few fruits at one time: parrots in
these trees rarely leave before all ripe fruits or buds have
been consumed. Other species, such as F. lutea and
A. carambola, promote communal feeding as they bear
many fruits that ripen simultaneously, attracting large groups
of parrots. Most but not all parrot food species are available
year-round but neither of our methods covered the annual
cycle sufficiently to allow conclusions across the whole year.
The relatively large proportion of introduced species in
in Madagascar, which is only recorded to include one
introduced species (Hampe 1989; Bollen and van Elsacker
2004). This could indicate a shortage of native food on
Praslin Island or simply reflect availability, or a combina-
tion of both. Madagascar is a much larger island with
higher species richness, a lower proportion of invasive
plants and relatively higher availability of native species
(Simberloff 1976; Kueffer et al. 2009). Coracopsis sibilans
in the Comoro Islands shows similar habitat preferences
to C. barklyi and feeds on introduced species in gardens
(Stevens et al. 1992).
An increase in introduced plant species has been
proposed as a reason for the increase in C. barklyi numbers
and range (Rocamora and Laboudallon 2009) but not
enough is known about the history of the Black Parrot’s
feeding habits in gardens and on farmland. Furthermore,
conflicts with fruit farmers are thought to be a threat for
2009). Particularly owners of A. carambola trees, which are
more valuable than A. bilimbi and are eaten more wastefully
than M. indica, complain about parrot damage to their fruit,
demand compensation (Rocamora and Laboudallon 2009)
and threaten to take action against the crop pest (AR, HR
and TP pers. obs.).
Diurnal feeding patterns
It is common practice to conduct parrot feeding studies
in hours of high parrot activity (Renton 2001; Ragusa-
Netto 2007; Matuzak et al. 2008), which may be problem-
atic if the study species prefers certain habitat types at
different times of the day. Evans (1979) noted regular
diurnal movements between the Vallée de Mai and coastal
regions, which concurs with our observations of parrot
traffic in the mornings and afternoons. Restricting our study
to early mornings and late afternoons would have favoured
palm forest species and underestimated the importance
of garden species. Frequency of feeding observations is
linked to detectability: in more open habitats parrots are
detected more easily, even when not calling. Black Parrots
call more frequently in the mornings and evenings (Gaymer
et al. 1969; Reuleaux et al. 2013), making them easier to
detect in closed habitats, such as palm forest. It is therefore
possible that the low number of feeding observations in
palm forest in the middle of the day was caused not by the
absence of feeding parrots, but by our inability to detect
them. Detectability does not, however, explain the absence
of feeding parrots in native scrub in the late morning.
Incidental feeding observations render more observa-
tions per time unit because locations with the highest
parrot feeding activity are targeted repeatedly. The much
higher number of feeding observations from this method
(six times as many bouts as in the transect approach) and
its rarefaction curve, which approaches the asymptote,
show that incidental observations are useful if the aim is
to compile a list of consumed species. One should not
conclude from incidental observations, however, that the
results accurately reflect proportion of observed food
species or plant parts in the diet, feeding duration or flock
size. For example, in this research, a few favoured parrot
feeding trees (Carica papaya), at the entrance to the
Vallée de Mai, concentrated observers’ efforts and had
a clear impact on the incidental feeding observation data
in that this species was substantially over-represented.
If quantitative information is required, it is important to
control for, or record, search effort, across habitats and
times of the day (and season).
Incidental observation data has its uses, however,
and with little additional effort can be collected alongside
other work. One strength of this method is anecdotal
information about rare incidents that can be important for
small populations. Feeding on scale insects, for example,
would not have been found had we only focused on
transects. Furthermore, incidental observations can
increase understanding of how food items are processed,
e.g. determining exactly which plant part is eaten may
require multiple observations and a good view, which is not
always possible from transects. Having different observers
but the divergence between them was so marked that it is
unlikely to be the only reason.
Thus, the two methods are not mutually exclusive alterna-
tives, but complementary. Deciding which method to adopt
depends on the aims of the research. A transect survey
provides data for quantitative questions, including identifi-
cation of key food species, feeding preferences, group size
and times of day, while incidental feeding observations
can produce supporting information, help to clarify feeding
strategies, and assist in compiling a non-prioritised list of
food species in a short time, especially in cases where very
little is known about a species’ feeding ecology. Parameters
such as feeding duration and number of individuals did not
produce reliable information from incidental observations
in this study.
Our research underlines the importance of endemic
palm species for the Seychelles Black Parrot, not only as
breeding habitat, but also as ideal feeding habitat. Exotic
species also play a role in the parrots’ diet and may
compensate for seasonal fluctuations in availability of native
species. Year-round transect survey feeding data would
determine seasonal changes in parrot feeding habits and,
in combination with ongoing phenology monitoring, provide
more insight into seasonal food shortages and potentially
To ensure sufficient year-round food availability for
other islands, the abundance of palms and native food
species in mixed forest and scrub should be increased.
For apparently preferred native species with locally limited
availability, e.g. N. vanhoutteanum, F. lutea and P. wrightii,
supplementary planting should be considered. Planting
exotic fruit trees to increase food availability, as has often
been suggested by the general public, is not recommended.
Not only are endemic and native trees more important
food sources for the parrots, planting of exotics counter-
acts the principle of a flagship species and may increase,
not lessen, conflict with local farmers. Increased public
education efforts would help to raise awareness among fruit
tree owners that parrot-caused damage is relatively limited
and may trigger greater understanding and appreciation of
the Seychelles’ national bird.
Foundation and Vallée de Mai staff, particularly Jovani Simeon,
for help with field work, and Frauke Fleischer-Dogley, Wilna
Accouche, Marc Jean-Baptiste, Marcus Pierre, Dainise Quatre and
Nathachia Pierre. We are also grateful to the many Praslinois who
permitted access to land, including the Seychelles National Parks
Authority, Praslin Development Fund, Fond Ferdinand and the
Coco de Mer Hotel. Many thanks to Christopher Kaiser-Bunbury
for statistical advice, to the Seychelles Bureau of Standards and
Seychelles Environment Department for approving and supporting
the research, and to the Environment Trust Fund Seychelles for
financial support. We are grateful to two anonymous referees
for reviewing and improving this article. Part of this study was
funded by the German Academic Exchange Service DAAD and
the Gesellschaft für Tropenornithologie GTO. MW is currently
supported by a grant from the Volkswagen Foundation, Germany.
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Received 1 September 2013, revised 6 April 2014, accepted 13 May 2014
Associate Editor: Lizanne Roxburgh