EPBC Nomination to list in the Endangered category:
Christmas Island flying-fox (Pteropus melanotus natalis)
Anyone may nominate a native species, ecological community or key threatening process for listing
under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).
You are invited to provide comment to assist the Threatened Species Scientific Committee (the
Committee) with its assessment of a nomination to list the Christmas Island flying-fox
(Pteropus melanotus natalis) as endangered under the EPBC Act.
The Committee welcomes the views of experts, stakeholders and the general public on nominations
to further inform its nomination assessment process.
In order to determine if a species, ecological community or threatening process is eligible for listing
under the EPBC Act, a rigorous scientific assessment of its status is undertaken. These assessments
are undertaken by the Committee to determine if an item is eligible for listing against a set of
criteria as set out in the guidelines for nominating and assessing threatened species and ecological
communities, and threatening processes. These are available at:
http://www.environment.gov.au/biodiversity/threatened/nominations.html
To assist in this matter, the Committee has identified a series of questions on which it seeks specific
comments (Part A).
The nomination for this item is provided in Part B. Individual nominations may vary considerably
in quality. Therefore in addition to the information presented in the nomination, the Committee also
takes into account published data and considers other information received when it prepares its
advice for the Minister.
Responses to this consultation will be provided in full to the Minister for Sustainability,
Environment, Water, Population and Communities. In providing comments, please provide
references to published data where possible. Should the Committee use the information you provide
in formulating its advice, the information will be attributed to you and referenced as ‘personal
communication’ unless you provide references or otherwise attribute this information.
The Committee’s advice may be published on the department’s website at completion of the
assessment and decision by the Minister. Information provided through consultation may be subject
to freedom of information legislation and court processes. It is also important to note that under the
EPBC Act, the deliberations and recommendations of the Committee are confidential until the
Minister has made a final decision on the nomination, unless otherwise determined by the Minister.
The views expressed within the attached nomination (Part B) do not necessarily reflect the opinions
of the Australian Government. The Australian Government and the Committee do not accept
responsibility for the accuracy or completeness of the contents of the nomination.
Included here for your consideration of the nomination are:
Part A — specific questions identified by the Committee
Part B — nomination
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 1 of 33
Part A — Questions on the Christmas Island flying-fox
1.
Can you comment on whether or not there is sufficient evidence to consider this entity a valid
sub-species?
2.
Are you able to provide an estimate of the current population size of mature adults of this
sub-species?
If the level of uncertainty is such that you are unable to provide a single number, please frame
your answer in terms of an estimated minimum, estimated maximum, best estimate, and your
overall level of confidence in these estimates:
3.

Lower bound

Upper bound

Best Estimate

Confidence (please answer in the range of 50–100%)
Do you accept James et al.’s (2007) estimate of 1,500 for the total population size of the subspecies? If not, why?
(James DJ, Dale GJ, Retallick K and Orchard K (2007). Christmas Island Biodiversity Monitoring Programme:
Christmas Island flying-fox Pteropus natalis. An assessment of conservation status and threats. Report to
Department of Finance and Deregulation, and Department of the Environment, Water, Heritage and the Arts. )
4.
Are you able to comment on the extent of decline in Christmas Island flying-fox population
size over the last approximately 27 years? (Note: the Department notes varying estimates for age at first
sexual maturity (particularly) and longevity, but for the purpose of this assessment, generation length for the
Christmas Island flying-fox has been estimated at 9 years. The listing guidelines consider decline over a period
of three generation lengths, which in this case is 27 years.)
If the level of uncertainty is such that you are unable to provide a single number (e.g.,
percentage decline), please frame your answer in terms of an estimated minimum, estimated
maximum, best estimate, and the overall level of confidence in these estimates:

Lower bound

Upper bound

Best Estimate

Confidence (please answer in the range of 50–100%)
5.
Do you agree that the threats listed are correct and that their effect on the sub-species is
significant?
6.
To what degree are the identified threats likely to impact on the sub-species in the future?
7.
Does the current and predicted rate of decline seem reasonable? Do you consider that the way
this has been derived is appropriate?
8.
Have you been involved in developing this nomination? If so, in what capacity?
9.
Do you agree with the proposal to list this sub-species?
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 2 of 33
Part B — Nomination
Section 1 - Legal Status, Distribution, Biological, Ecological
Conservation Theme
1. Not applicable - there is no
N/A
conservation theme for the 2011
assessment period.
Taxonomy
2. What are the currently
accepted scientific and common
name/s for the species (please
include Indigenous names, where
known)?
Note any other scientific names that
have been used recently. Note the
species authority and the Order and
Family to which the species belongs
(Family name alone is sufficient for
plants, however, both Order and
Family name are required for
insects).
3. Is this species conventionally
accepted? If not, explain why. Is
there any controversy about the
taxonomy?
Christmas Island flying-fox Pteropus melanotus natalis.
[Across its international range, the species as a whole is
named Blyth’s flying-fox.]
[Order Chiroptera; Family Pteropodidae]
The taxonomic status of this entity is poorly resolved. It
was originally described (Thomas 1887) as a distinct
species restricted to Christmas Island. Without substantial
evidence, Chasen (1940) subsumed it and a series of
previously-recognised species (P. melanotus [from the
Andaman and Nicobar islands], P. tytleri [from the South
Andaman and Rutlans islands] and P. modiglianii [from the
Mentawi islands]) as subspecies within P. melanotus.
There remains some uncertainty about the subspecific
bounds for taxa other than natalis: Mickleburgh et al.
(1992) include P. m. melanotus (Nicobar Islands), P. m.
modiglianii (Enggano Island), P. m. niadicus (Nias Island),
P. m. satyrus (North Andaman Islands) and P. m. tytleri
(South Andaman Islands).
However, there has been no genetic or morphological
assessment of this treatment. Tidemann (1985)
considered the case for inclusion of natalis within P.
melanotus was “unlikely given the degree of separation
involved and the tendency towards a high degree of
speciation in the genus”. Genetic work currently in
progress (XXXX XXXX, pers. comm., 2012) possibly
indicates that specific, rather than subspecific, status is
warranted for natalis.
The taxonomic status of the Christmas Island flying-fox
needs to be resolved with molecular phylogenetic work
considering relationships with other flying-foxes from the
northern Indian Ocean and south-east Asia populations.
4. If the species is NOT
conventionally accepted, please
provide:
n/a
(i) a taxonomic description of the
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 3 of 33
species in a form suitable for publication
in conventional scientific literature; OR
(ii) evidence that a scientific institution
has a specimen of the species and a
written statement signed by a person
who has relevant taxonomic expertise
(has worked, or is a published author,
on the class of species nominated), that
the person thinks the species is a new
species.
5. Is this species taxonomically
distinct (Taxonomic distinctiveness
– a measure of how unique a
species is relative to other species)?
No particular taxonomic distinctiveness – the genus
Pteropus is speciose.
In the Christmas Island context, it may now be
taxonomically distinct. Of five endemic mammal taxa
present at the time of the Island’s settlement (1890s), the
flying-fox is the only native mammal species now known to
be extant (the persistence of the Christmas Island shrew is
uncertain, with last record in 1985: Schulz 2004).
Legal Status
6. What is the species’ current
conservation status under
Australian and State/Territory
Government legislation?
7. Does the species have specific
protection (e.g. listed on an annex
or appendix) under other legislation
or intergovernmental
arrangements, e.g. Convention on
International Trade in Endangered
Fauna and Flora (CITES),
Convention on Migratory Species
(CMS).
This subspecies occurs only on the Australian external
territory of Christmas Island. It is not listed as threatened
in any Australian jurisdiction.
The distribution of the taxon is restricted to Christmas
Island, mostly (63%) included within a national park,
where it is protected. Under EPBC Act regulations, it is
also afforded some protection in those parts of Christmas
Island outside the Park area.
All flying-foxes (Pteropus spp.) are listed under CITES
Appendix II.
The species Pteropus melanotus is listed as Vulnerable by
the IUCN, with the comment that “if the Christmas Island
population was found to be specifically distinct, it would be
assessed as Critically Endangered.”
(http://www.iucnredlist.org/apps/redlist/details/18740/0).
Note
The Christmas Island flying-fox was nominated previously
(in 2007), but was found not eligible for listing
(http://www.environment.gov.au/biodiversity/threatened/s
pecies/pteropus-melanotus-natalis.html).
Since that assessment, the IUCN has rated the taxon (if
considered a species) as “Critically Endangered”, and the
Christmas Island Expert Working Group (Beeton et al.
2010) has considered its conservation outlook cause for
serious concern, and recommended a series of “urgent”
actions, including “To avoid a repeat of the Pipistrelle
extinction for the island’s remaining native mammal, it is
imperative that a recognisable ‘trigger point’ be established
that facilitates immediate management interventions.
These should include the commencement of active
demographic monitoring, a screening of blood for
assessment of pesticide residues and potential antibodies
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 4 of 33
to diseases, and a captive breeding program as insurance
against probable extinction.”
The material presented here includes some information not
presented in the previous consideration of this species.
Description
8. Give a brief description of the
species’ appearance, including size
and/or weight, and sex and age
variation if appropriate; social
structure and dispersion (e.g.
solitary/clumped/flocks).
9. Give a brief description of the
species’ ecological role (for
example, is it a ‘keystone’ or
‘foundation’ species, does it play a
role in processes such as seed
dispersal or pollination).
The Christmas Island flying-fox is a relatively small
Pteropus (weight 250-500 g), described as “uniform nearblack, longish fur (giving a chubby appearance); vague
reddish collar in some individuals” (Tidemann and Richards
2008).
Individuals mostly roost in groups. Unlike most bats, it is
active not only at night but also during part of the day.
Flying-foxes are recognised to be keystone species, playing
a significant role in pollination and dispersal of plants with
fleshy fruits. This role may be especially important on
islands, where flying-foxes may be the only species with
this ecological function (Cox et al. 1991; Cox and Elmqvist
2000). Such is the case for this species on Christmas
Island, where there are no other extant bats, the only
other vertebrate frugivore is the Christmas Island imperial
pigeon Ducula whartoni, and there are no other specialised
vertebrate pollinators.
The Christmas Island Expert Working Group noted: “The
significance of the endemic Christmas Island Flying-fox in
maintaining key ecosystem processes in the rainforest of
Christmas Island cannot be overestimated and this taxon
remains an important ‘keystone’ species.” (Beeton et al.
2010).
Australian Distribution
10. Describe the species’ current
and past distribution in the
Australian distribution and, if
available, attach a maps noting the
source and the datasets used to
create these.
11. What is the extent of
occurrence (in km2) for the
species (described in Attachment
A); explain how it was calculated
and provide information on data
sources.
a.
b.
What is the current extent of
occurrence?
What data are there to indicate
past declines in extent of
occurrence (if available, include
data that indicates the
percentage decline over the
past 10 years or 3 generations
whichever is longer)?
The Christmas Island flying-fox is endemic to the 135 km2
Christmas Island. It has never been reported beyond this
island. Its former and current distribution extends across
the entire island.
Christmas Island is 135 km2. This corresponds to the
extent of occurrence of this species.
135 km2.
Some (James et al. (2007) considers three of six)
historically known roost sites are no longer occupied, but
the species still forages across the extent of its former
range.
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 5 of 33
c. What data are there to indicate
future changes in extent of
occurrence (if available, include
data that indicates the
percentage decline over 10
years or 3 generations
whichever is longer (up to a
maximum of 100 years in the
future) where the time period is
a continuous period that may
include a component of the
past)?
12. What is the area of
occupancy (in km2) for the species
(described in Attachment A);
explain how it was calculated and
provide information on data sources
a.
b.
c.
What is the current area of
occupancy?
What data are there to indicate
past declines in area of
occupancy (if available, include
data that indicates the
percentage decline over the
past 10 years or 3 generations
whichever is longer)?
What data are there to indicate
future changes in area of
occupancy (if available, include
data that indicates the
percentage decline over 10
years or 3 generations
whichever is longer (up to a
maximum of 100 years in the
future) where the time period is
a continuous period that may
include a component of the
past)?
13. How many natural locations
do you consider the species occurs
in and why? Where are these
located? Provide latitude, longitude,
map datum and location name,
where available, in an attached
table.
No information available.
The total area of the three known existing maternity roost
sites (Hosnie’s Spring, McMicken Point [Dolly Beach] and
Greta Beach) is ca. 10 ha. This may be considered to
comprise the entire breeding area, and hence area of
occupancy.
If not, the area of occupancy is the same as the extent of
occurrence for this species.
See 12.
Some previously known communal roosts are no longer
used. For example, roosts were recorded near Daniel Roux
cave and Middle Point in the 1980s (Tidemann 1985). No
roosts have been recorded at these sites in more recent
studies (James et al. 2007).
No information available
The species occurs at only one natural location – Christmas
Island. During foraging it may occur across the entire
Island. Known main roost sites are presented in Figure 1,
recognising that there are also some smaller (nonmaternity) roost sites.
The term 'location' defines a
geographically or ecologically distinct
area.
14. Give locations of other
populations: captive/propagated
populations; populations recently
re-introduced to the wild; and sites
for proposed population reintroductions. Note if these sites
have been identified in recovery
plans. Provide latitude, longitude,
map datum and location name,
where available, in an attached
table.
15. Is the species’ distribution
severely fragmented? What is the
No other populations exist.
All individuals occur in one population.
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 6 of 33
cause of this fragmentation?
Describe any biological, geographic,
human-induced or other barriers
causing this species’ populations to
be fragmented.
Severely fragmented refers to the
situation in which increased extinction
risk to the taxon results from most
individuals being found in small and
relatively isolated subpopulations (in
certain circumstances this may be
inferred from habitat information).
These small subpopulations may go
extinct, with a reduced probability of
recolonisation.
16. Departmental Use Only:
Global Distribution
17. Describe the species’ global
distribution.
18. Give an overview of the global
population’s size, trends, threats
and security of the species outside
Australia.
If natalis is considered a subspecies of P. melanotus, then
the species also occurs on a small set of islands in the
north-eastern Indian Ocean, notably the Andaman islands,
Nicobar islands, Rutlans islands, the Mentawi islands and
Sumatra.
The IUCN recognises the global status of P. melanotus as
vulnerable, due to small total population size, small area of
occupancy and continuing decline, in part due to hunting
and extensive habitat clearance on some islands. The
population on Enggano Island is believed to have been
extirpated following a severe typhoon
(http://www.iucnredlist.org/apps/redlist/details/18740/0)
19. Explain the relationship
between the Australian population
and the global population,
including:
a.
What percentage of the global
population occurs in Australia;
b.
Is the Australian population
distinct, geographically
separate or does part or all of
the population move in/out of
Australia’s jurisdiction (give an
overview; details in Movements
section);
Do global threats affect the
Australian population?
c.
The taxon Pteropus melanotus natalis is restricted to
Christmas Island.
The population sizes of other subspecies of P. melanotus
are not known.
There is no movement of the taxon P. melanotus natalis
into or out of Australia.
The Christmas Island flying-fox may be affected by
introduction of new diseases to the island, and potentially
by increased risk of severe cyclones associated with global
climate change.
Surveys and Monitoring
20. Has the species been
reasonably well surveyed?
Provide an overview of surveys to date
and the likelihood of the species’ its
current known distribution and/or
population size being its actual
distribution and/or population size.
Include references documenting the
Flying-foxes in general are somewhat difficult to survey,
because the location of roosting camps, and the relative
and absolute number of individuals in these camps may be
mercurial, changing seasonally and even from day-to-day.
A further problem is that – at least for the Christmas Island
flying-fox – an unknown proportion of the population may
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 7 of 33
current known distribution and location
records and survey methodology where
available.
roost away from communal camps, either singly or in small
groups (Tidemann 1985).
Nonetheless, counts at communal camps are the most
effective way to estimate population size, with nearsynchronous counts at all known camps being the most
effective means of dealing with irregular shifts of
individuals between camps.
In the case of the Christmas Island flying-fox, there are
few (known) camps, and at least some of these are known
to have been relatively permanent and long-used (notably
Hosnies Spring: Tidemann 1985; James et al. 2007).
Tidemann (1985) attempted to estimate total population
size through counting all individuals at all known camps
and then adding a further guess for the number of
individuals roosting solitarily or in small (and unknown)
camps. Subsequently Orchard (2006) and James et al.
(2007) undertook wide-ranging searches and concluded
that there were then few individuals roosting away from
the then three known camps, suggesting that this
proportion had declined considerably since Tidemann’s
1984 study.
The number of individuals in flying-fox colonies has been
estimated through ground counts (where the observer
walks through the camp and attempts to count all
individuals roosting in every tree) and exit counts (where
the observer is based at a vantage point outside the camp
area and attempts to count all the bats emerging from the
camp at dusk). Both procedures have been used for
Christmas Island flying-foxes, however the correlation
between the two methods is not particularly high (James et
al. 2007), and the part-diurnal activity rhythm of
Christmas Island flying-foxes may make for some
complications in exit counting.
For flying-fox counts in mainland Australia, Westcott et al.
(in prep.) considers that ground counts are preferable,
because they provide greater precision, and can more
readily detect population structure parameters. Ground
counts of Christmas Island flying-foxes (from the Parks
Australia data base) since 2006 are summarised in
Attachment 1.
However, some colony sites on Christmas Island (notably
McMicken’s Point) are difficult to access, and there may be
valid reason for using exit counts in such cases.
On Christmas Island, flying foxes have also been surveyed
away from their known colony sites. The Biodiversity
Monitoring Program (BMP: James et al. 2007) recorded
flying-foxes (and birds) in diurnal samples from a set of
128 sites across the Island (each sampled four times), but
had a relatively low incidence of flying-fox presence (5%).
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 8 of 33
A subset of 109 of these sites was also sampled (four times
each) at night over the period June-July 2006, with
appreciably higher recording rate (82 flying-fox records,
=19% of samples). To date, neither of these surveys has
been repeated, but the nocturnal sampling provides a
robust framework for assessing trends in abundance.
Flying-foxes have also been recorded in the “Island-wide
survey” (IWS), a similarly broad-scale sampling of
components of the Island’s biodiversity, established initially
to map the distribution of yellow crazy ants, and repeated
at two-year intervals. This approach may be less robust
than the BMP nocturnal sampling for flying-foxes because it
is spaced over a much longer period (sampling takes about
4 months), so may involve many re-counts of the same
individuals as the bats move about the Island.
Furthermore, the extent to which flying-foxes have been
included as target survey species has varied considerably
across the years of the IWS, rendering it extremely difficult
to use this source for monitoring (at least retrospectively).
However, it includes very many sample points, and also
records the occurrence of flying-foxes observed
opportunistically (i.e. including away from fixed sampling
points). The incidence of flying-fox records across IWS
samples is given in Attachment 3.
The geographic extent of the IWS and BMP provides an
unusually high level of confidence that all main camps have
been detected.
21. For species nominated as
n/a
extinct or extinct in the wild, please
provide details of the most recent
known collection, or authenticated
sighting of the species, and
whether additional populations are
likely to exist and the basis for this
assertion. Provide latitude,
longitude, map datum and location
name, where available.
22. Is there an ongoing
monitoring programme? If so,
please describe the extent and
length of the programme.
Currently, the species is monitored (every two years)
through the IWS, and through occasional counts at
colonies. The frequency of ground and exit count
monitoring was very limited for the period 2009-2011.
A more formal monitoring program is proposed from 2012,
including annual re-counting of the BMP nocturnal sites,
and synchronous ground-counts of all colony sites, at least
three times per year.
The disease status of this species (and some other native
and introduced species) has been sampled in 2010, and
Hall et al. (2011) has recommended ongoing monitoring of
this status.
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 9 of 33
Life Cycle and Population
23. What is the species’ total
population size in terms of number
of mature individuals? How were
population estimates derived and
are they reliable? Are there other
useful measures of population size
and what are they?
In the absence of figures, terms such as
common, abundant, scarce can be of value.
James et al. (2007) provides the most recent estimate of
total population size, based on near-simultaneous counts
of the known roost sites. On the basis of these counts,
James et al. (2007) considered that the total population in
2006 was “between 1,500 and 2,000, but probably closer
to 1,500.” “All other counts between December 2005 and
August 2006 provided estimates of no more than 500 bats
in the known camps and a population estimate of 5001,000 individuals.”
Note that these tallies refer to the total number of
individuals rather than to mature individuals. The
proportion of juveniles and sub-adults in these counts is
uncertain. One independent measure of the proportion of
mature individuals in the total population is provided by
Hall et al. (2011) who aged flying-foxes caught in mist nets
for disease assay. Of 28 individuals caught (in July-August
2010), 12 (43%) were categorised as “mature”. Of 126
individuals captured by Tidemann in March and September
1984, 71 (56%) were classed by him as “sexually mature”
[his Fig. 19]. Although these data are meagre, this
suggests a total population of 1500 bats is likely to include
about 750 mature individuals.
24. Does the species occur in a
number of smaller populations?
How many? For each population
give the locality, numbers and
trends in numbers and tenure of
land (include extinct populations).
Can these be considered to be
subpopulations and why?
Subpopulations are defined as
geographically or otherwise distinct groups in
the population between which there is little
demographic or genetic exchange.
The Christmas Island flying-fox occurs only on Christmas
Island. Given that other species of flying-foxes are known
to disperse for foraging over distances of 50 km in any
night (e.g. Palmer and Woinarski 1999), flying-foxes on
the 135 km2 Christmas Island should be considered to be a
single population. This is reflected also in the chaotic
variation in numbers of individuals recorded at roost sites,
with such variation mostly indicating movement of
individuals between roosts.
Nonetheless, the extant major maternity roost sites
(particularly Hosnie’s Spring, McMicken Point) merit
recognition, because they are known to have been used for
decades, and because they may frequently include a high
proportion of the bat’s total population.
Hosnie’s Spring (10o28.5’S, 105o41’E) lies within the
Christmas Island National Park. The roost area also occurs
within a Ramsar site. The features, ecology and
management of that site have recently been reviewed
(Hale and Butcher 2010), but that account fails to
recognise its value for Christmas Island flying-fox,
notwithstanding that the area is the main known maternity
roost site, and the significant ecological role of the flyingfoxes in maintaining floristic diversity and functionality of
the site.
McMicken Point (Dolly Beach) (10o31.5’S, 105o40.8’E) also
lies within Christmas Island National Park.
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 10 of 33
Population counts for these and other sites are presented
in Attachment 1.
25. Provide details on ages of the
following:
a. sexual maturity;
b.
life expectancy;
c.
natural mortality.
For flying-foxes generally, most females will be sexually
mature in their third year (Martin and McIlwee 2002), but
Tidemann (1985) considered some Christmas Island flyingfox females may be reproductively mature at six months.
For pteropids generally, life expectancy is uncertain but
likely to be 15-20 years (Martin and McIlwee 2002).
Patterns of natural mortality in the Christmas Island flyingfox are poorly known. Tidemann (1985; Tidemann et al.
1994) reported that Christmas Island flying-foxes
constituted a high proportion of the diet of feral cats (21%
by weight [with incidence of 10%] of all stomach contents
in 93 cat stomachs examined), in part due to the bat’s
habit of foraging on fruits in low shrubs, particularly the
introduced Jamaican (Japanese) cherry Muntingia calabura.
26. Reproduction
For plants: When does the species
flower and set fruit? What
conditions are needed for this?
What is the pollinating mechanism?
If the species is capable of
vegetative reproduction, a
description of how this occurs, the
conditions needed and when. Does
the species require a disturbance
regime (e.g. fire, cleared ground) in
order to reproduce?
For animals: provide overview of
breeding system and of breeding
success, including: when does it
breed; what conditions are needed
for breeding; are there any
breeding behaviours that may make
it vulnerable to a threatening
process?
The Christmas Island flying-fox has a typical flying-fox life
history, with animals being long-lived but with relatively
low reproductive output. Females give birth to one young
per year, typically in a relatively synchronised breeding
season (most births in February: Tidemann 1985; most
birth between December and February: James et al. 2007).
The mating system is probably polygamous or
promiscuous. In most flying-foxes, females are 3 years old
at first breeding, but some may breed in their second year
(Martin and McIlwee 2002). In contrast, Tidemann (1985)
considered that for the Christmas Island flying-fox,
“females grow rapidly and can become pregnant when they
are only six months old. By contrast, males are thought to
take eighteen months to mature.” In a recent assessment
of the health status of Christmas Island flying-foxes, Hall
et al. (2011) categorised the age status of captured flyingfox as either juvenile (<1 yr), sub-adult (1-3 yrs) or adult
(>3 yrs).
The gestation period is five months (Tidemann 1985).
Longevity for flying-foxes generally in the wild is probably
15-20 years (Martin and McIlwee 2002; Tidemann and
Nelson in press).
Tight coloniality and synchronised breeding may render the
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 11 of 33
species more vulnerable, with all breeding females and
their dependent young localised in a few small areas (i.e.
three known breeding colonies on Christmas Island) during
part of the year.
Other flying-foxes are known to suffer massive
synchronised losses of foetuses or recently-born young
under some conditions of stress, unusual food shortages or
heat spells (Martin and McIlwee 2002).
The low reproductive output renders the Christmas Island
flying-fox (and other pteropodids) likely to be slow to
recover from major mortality events.
Tidemann (1985) recorded a far higher proportion of
mature females than mature males in his samples, and
considered that this indicated a polygamous mating
system, longer period to maturity in males than in females,
and shorter life-span in males than females.
27. What is the population trend
for the entire species?
a.
What data are there to indicate
past decline in size (if
available, include data on rate
of decline over past 10 years or
3 generations whichever is
longer)?
Andrews (1900) provided the first description of the
ecology, status and habits of the Christmas Island flyingfox, within about ten years of the Island’s initial
settlement. He noted that it was “very common all over
the island, and at the settlement causes great destruction
of fruit … When the wild fruits are ripe comparatively few
of these bats visit the gardens, but great numbers may be
seen feeding in the forest.”
The next assessment of its status was by Gibson-Hill
(1947), who noted that the Christmas Island flying-fox was
“flourishing”, and “even a nuisance as it fed freely on the
papayas”.
The next account was by Tidemann (1985) who conducted
a detailed study of the species in 1984. His introductory
remarks note that long-term residents considered that the
species had declined since Gibson-Hill’s account, with the
suggestion that such decline was due to rainforest
clearance. In September 1984, Tidemann counted 3500
bats at all the then known colonies (three maternity
colonies and two other camps), estimated that a further
2500 bats were thought to be roosting singly or in small
groups (with this estimate largely based on many bats
seen roosting in small groups along the northern
coastline), and hence concluded that the population then
was 6000 individuals.
James et al. (2007) noted that “No survey work was
carried out on P. natalis during the 1990s. However,
anecdotal evidence collected from long-term residents of
the island suggested that dramatic population declines
occurred during the mid 1990s (Orchard 2006).”
and “By 2000 there was a common belief amongst
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 12 of 33
residents and regular visitors to the island that the flyingfoxes had declined over the previous decade or so”.
The next quantitative assessment of its status was in 2002,
as part of an environmental impact assessment in 2002:
Corbett et al. (2003) sampled extensively across the
Island, but recorded a maximum of 30 individual flyingfoxes, and concluded that the total population was
“probably in the order of 500-1,000 individuals”.
The most recent account of the species’ status was through
a series of intensive studies and regular monitoring in the
period 2004-07 (reported in Orchard 2006 and James et al.
2007). On the basis of these counts, Orchard (2006)
estimated that the “current population levels are low,
possibly as few as 500 individuals.” James et al. (2007)
considered that the total population in 2006 was “between
1,500 and 2,000, but probably closer to 1,500.” This
estimate was much influenced by a single count of 1,381
individuals in September 2006 which substantially
exceeded other counts. “All other counts between
December 2005 and August 2006 provided estimates of no
more than 500 bats in the known camps and a population
estimate of 500-1,000 individuals.”
Ground counts of known colonies from 2006-2011 are
summarised in Attachment 1. In addition to these counts,
Hall et al. (2011) reported ground counts of 12 bats [with
“more bats audible but not seen”] at Hosnies Spring (July
2010), 19 (exit count at Margaret Knoll of bats from
Hosnies Spring) in July 2010, 4 at the Golf Course roost in
July 2010, <10 flying and foraging around Flying Fish Cove
(August 2010) and 11 roosting at Ethel Beach in August
2010. Hall et al. (2011) also reported that the Hosnies
Spring site was “recently damaged by the collapse of a
large tree”. They also noted that ”Observations at Hosnies
Springs, Ethel Beach and the Golf Course revealed fewer
flying foxes than reports of previous observations
conveyed to us.”
Orchard (2006) and James et al. (2007) both reported very
few bats roosting singly or in small groups along the
northern coastline (contra the observations of Tidemann
(1985)).
A summary interpretation of these few and intermittent
markers of historic trends is that the Christmas Island
flying-fox declined more or less continuously from the
1890s settlement (when “very common all over the
island”) to 1984 (when Tidemann (1985) estimated the
population at 6000, then declined sharply between then
and the next near-comprehensive assessment of its status
in 2006 (James et al. 2007). The decline over that 22 year
period is about 75% (i.e. 6000 to 1500 individuals), which
could be plausibly extrapolated to a decline of >80% over
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 13 of 33
the 3-generation period 1981-2011. This decline may have
been an abrupt response to the 1988 storm, or more
gradual and continuous, but the evidence is tenuous. The
limited available information is insufficient to characterise
trends since 2007, but the Island-wide Survey information
suggests that the population may have stabilised, whereas
the (few) ground counts suggest ongoing decline.
Unusually high counts were recorded from a small number
of samples around September 2007, particularly from exit
counts at McMicken Point. The count on 26 September
2007 exceeds by about 1000 individuals all other counts
from the same site. This data point was highly influential
in the previous assessment of the conservation status of
this species (of 2007-08), as it suggested the population
has stabilised or begun to increase. The information was
reported as “Subsequent unpublished data from Parks
Australia indicate that around 2300 bats were counted in
September 2007 (Parks Australia, unpubl. data, 2007b).
This did not include a ground count from an as yet
unidentified camp site suspected to exist near Murray Hill.
Parks Australia has also made no firm estimate of the
number of bats outside known camps, but estimates the
total number including dispersed individuals could now be
around 4000 (Parks Australia, unpubl. data, 2007b).”
(Threatened Species Scientific Committee 2008:
http://www.environment.gov.au/biodiversity/threatened/species/pterop
us-melanotus-natalis.html). This information appears to be at
variance with the counts recorded in the ground-count data
base, and with estimates made in 2007 (James et al.
2007).
Counts subsequent to this September 2007 value are
consistently appreciably lower than the that value, and the
limited monitoring over the period 2008-2011 indicates far
smaller population size.
b. What data are there to indicate
future changes in size (if
available, include data which
will indicate the percentage of
decline over 10 years or 3
generations whichever in longer
(up to a maximum of 100 years
in the future) where the time
period is a continuous period
that may include a component
of the past)?
28. Does the species undergo
extreme natural fluctuations in
population numbers, extent of
occurrence or area of occupancy?
To what extent and why?
Extreme fluctuations can be said to occur
in a number of taxa when population size or
distribution area varies widely, rapidly and
frequently, typically with a variation greater
than one order of magnitude (i.e. a tenfold
There are no data to indicate future trends in population
size.
Extreme fluctuations in population are reported for other
island-endemic flying-foxes elsewhere in the Indian Ocean
in response to major mortality and habitat loss associated
with irregular cyclones and other storm events (Cheke and
Dahl 1981; Powell and Wehnelt 2003), but the frequency
of such severe weather events on Christmas Island has
been lower than that for other Indian Ocean islands.
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 14 of 33
increase or decrease).
29. What is the generation
length and how it is calculated?
Generation length is the average age of
parents of the current cohort (i.e. newborn
individuals in the population). Generation length
therefore reflects the turnover rate of breeding
individuals in a population. Generation length is
greater than the age at first breeding and less
than the age of the oldest breeding individual,
except in taxa that breed only once. Where
generation length varies under threat, the more
natural, i.e. pre-disturbance, generation length
should be used.
30. Identify important
populations necessary for the
species’ long-term survival and
recovery? This may include: key
breeding populations, those near the
edge of the species’ range or those
needed to maintain genetic diversity.
31. Describe any cross-breeding
Although the total population of Christmas Island flying-fox
may not vary much across any year, there may be
substantial fluctuations in the number of individuals
present in any colony. This “noise” renders estimation of
population, and comparisons between periods, challenging.
Age at first breeding for most females is likely to be 2-3
years, and longevity about 10-20 years, so a reasonable
estimate of generation length is 10 years (with range 6-12
years).
A very recent study (Tidemann and Nelson in press), based
on banding returns, calculated that the generation length
for grey-headed flying-fox Pteropus poliocephalus was 7.4
years, and the oldest recorded individual in that study was
18 years.
As for q24 above, the Christmas Island flying-fox is
considered to have only one population. However, within
its Christmas Island range, the maternity colonies at
Hosnie’s Spring and McMicken Point (and perhaps Greta
Beach) typically comprise most of the entire population
(and all of the breeding females), and have been known as
maternity sites for at least several decades.
Nil.
with other species in the wild,
indicating how frequently and where
this occurs.
32. Departmental Use only:
Populations In Reserve
33. Which populations are in
reserve systems? Which of these
are actively managed for this
species? Give details.
Most of the current population is likely to occur in
Christmas Island National Park, which constitutes 63% of
the Island. Both major maternity colonies occur within the
Park.
Management actions address some putative threats to this
(and many other) species in the park area (and outside it).
This includes episodic baiting for yellow crazy ants. A
control program for cats and black rats started in 2010.
Habitat
34. Describe the species’ habitat
(e.g. aspect, topography, substrate,
climate, forest type, associated
species, sympatric species). If the
species uses different habitats for
different activities (e.g. breeding,
feeding, roosting, dispersing,
basking), then describe each
habitat.
35. Does the species use refuge
habitat, e.g. in times of fire,
drought or flood? Describe this
habitat.
The species occurs across all habitats on Christmas Island.
Most roosts are close to the coast, presumably for ease of
take-off and access to updrafts (Tidemann 1985).
Foraging occurs in rainforests, gardens, and post-mine
revegetation (where this contains trees and shrubs).
No known refuge habitat; however at roosts this species
may be susceptible to disturbance by yellow crazy ants,
and it may be critical that known roost sites are kept free
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 15 of 33
36. Is the extent or quality of the
species’ habitat in decline? If the
species uses different habitats,
specify which of these are in
decline.
of super-colonies of this introduced ant.
Much of Christmas Island has undergone broad-scale
ecological change over the last few decades associated
with outbreaks of yellow crazy ants. Such changes include
marked reduction in the Island’s endemic red crab
population, causing increases in the cover of understorey
and ground litter, and some broad-scale floristic changes
(O’Dowd et al. 2003).
In areas with super-colonies of yellow crazy ants, the
exceptionally high abundance of “farmed” scale insects
may cause extensive degradation of foliage (in some cases,
leading to death of trees), with some tree species (notably
the Tahitian chestnut Inocarpus fagifer particularly affected
(Green et al. 2001). This species was listed by Andrews
(1900) as one of two native trees whose fruit was
particularly favoured by flying-foxes. Currently, the extent
to which such resulting floristic change may be detrimental
(or beneficial) to flying-foxes is not known.
In addition to habitat structural and floristic changes due to
the influence of yellow crazy ants, a series of weed species
has increased in extent and abundance. Such weeds
include some species now much used as food resources by
the flying-fox (notably Jamaican (Japanese) cherry
Muntingia calabura) (and the flying-fox is probably an
important disperser for this weed), but weed proliferation
may also be detrimental to native plants used by the
flying-fox.
37. Is the species part of, or does
it rely on, a listed threatened
ecological community? Is it
associated with any other listed
threatened species?
More than 100 years of phosphate mining has led to the
loss of about 25% of the Island’s rainforest habitat.
However, parts of these mined areas are now being
rehabilitated, and under current legislation no further
clearance of primary rainforest to allow for mining access is
permitted.
The Christmas Island flying-fox is not associated with any
currently-listed threatened ecological community. It
occurs with a range of other threatened species including
Christmas Island pipistrelle Pipistrellus murrayi (EPBCAlisted as critically endangered), Lister’s gecko
Lepidodactylus listeri (EPBCA-listed as vulnerable),
Christmas Island blind snake Typhlops exocoeti (EPBCAlisted as vulnerable), Abbott’s booby Papasula abbotti
(EPBCA-listed as endangered), Christmas Island frigatebird
Fregata andrewsi (EPBCA-listed as vulnerable), Christmas
Island emerald dove Chalcophaps indica natalis (EPBCAlisted as endangered), Christmas Island goshawk Accipiter
hiogaster natalis (EPBCA-listed as endangered), Christmas
Island hawk-owl Ninox natalis (EPBCA-listed as
vulnerable), Christmas Island thrush Turdus poliocephalus
erythropleurus (EPBCA-listed as endangered), Christmas
Island shrew Crocidura trichura (EPBCA-listed as
endangered), and the plants Tectaria devexa (EPBCA-listed
as endangered) and Carmona retusa (EPBCA-listed as
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 16 of 33
vulnerable).
Although not strictly relevant to considerations under
Australian legislation, it is notable that island-endemic
flying-foxes have a global record of high levels of extinction
and endangerment (Fleming and Recey 2009).
Feeding
38. Summarize the species’ food
items or sources and
timing/seasonality.
39. Briefly describe the species’
feeding behaviours, including
those that may make the species
vulnerable to a threatening process.
Christmas Island flying-foxes eat a wide range of fruit and
nectar from native and introduced plant species. James et
al. (2007) tallied this at 35 species, including 18 introduced
species. Some important sources include Barringtonia
racemosa (flowers), Celtis timorensis (stinkwood (fruit)),
Dysoxylum gaudichaudianum (flowers), Ficus macrocarpa
(fruit), Inocarpus fagifer (Tahitian chestnut (fruit)),
Macaranga tanarius (flowers), Maclura cochinchinensis
(fruit), Planchonella nitida (fruit, flowers), Syzygium
nervosum (flowers, fruit), Terminalia catappa (Indian
almond (flowers, fruit)), Tristiropsis acutangula (flowers,
fruit) (James et al. 2007), Muntingia calabura (Jamaican
cherry (fruit)), Cocos nucifera (coconut (flowers)),
Mangifera spp. (mango (fruit)), Annona muricate (soursop
(fruit)), and A. reticulata (custard apple (fruit)). James et
al. (2007) also reported an observation of flying-foxes
eating the leaves of an unknown native tree.
Dietary patterns change seasonally, in response to the
phenological patterning of individual plant species. Fruit
availability is probably greatest in the wet season
(December-March).
The Christmas Island flying-fox forages at night and over
part of the day. Day-time foraging is considered to be an
evolutionary response to limited predation pressure
(Tidemann 1985).
Most foraging is in the tree canopy, but flying-foxes are
also attracted to the fruits of the introduced Jamaican
(Japanese) cherry, which often occur within 1-2 m of the
ground. This species now occurs widely across the Island,
and the low-level foraging by bats on the fruits of this plant
render the flying-foxes particularly susceptible to predation
by feral cats.
In the past, Christmas Island flying-foxes consumption of
fruits of horticultural plants (particularly pawpaw and
mango) led to them being considered as pests by some
members of the community, and accordingly killed.
Previously, some hunters used fruit baits to attract flyingfoxes to convenient sites for capture (James et al. 2007).
Maternity roost sites are likely to be “traditional” and longlasting, and sited to be close to areas of forest with
productive fruit crops (to minimise energy expenditure by
females carrying young). If extensive areas of forest near
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 17 of 33
such maternity roost sites are cleared or degraded by crazy
ants, then such change may lead to unsustainable increase
in the energy costs for female flying-foxes.
Movement Patterns (fauna species only)
40. Describe any relevant daily
and seasonal pattern of
movement for the species, or
other irregular patterns of
movement, including relevant
arrival/departure dates if migratory.
41. Give details of the species’
home ranges/territories.
Tidemann (1985) reported that “many bats were seen to
fly great distances after gaining height above their roosts.
In some cases they flew out of sight at least 5 km away.”
Home range size is not known, but given reported and
probable movements, it is likely that all bats may occur
across the entire Island over the course of their daily,
seasonal or annual foraging.
Survey Guidelines
42. Give details of the
distinctiveness and detectability
of the species.
For survey, there are no issues with distinctiveness. It is
the only bat on Christmas Island.
For population estimation, detectability is an issue, in that
an unknown proportion of the population is thought to
occur in small roosts away from the main colonial roosting
sites. Detectability may also be constrained by the dense
foliage and tall vegetation in its main habitat, rainforest.
43. Describe methods for
detecting species including when
to conduct surveys (e.g. season,
time of day, weather conditions);
length, intensity and pattern of
search effort; and limitations and
expert acceptance; recommended
methods; survey-effort guide.
Nonetheless, this is typically a noisy species, and, if
present, it is likely to be detected during nocturnal
spotlight searching.
See q.20 and q22.
Ground-counts at known colony sites provide the most
reliable measures of total population size, and should be
conducted near synchronously across all colonies. Dense
foliage and tall trees may reduce the precision of such
counts. “Double-counting” (i.e. cross-checking between
two observers) will increase precision. The number of
“pups” should also be included in counts.
These counts (estimates of total population size) should be
complemented by more wide-ranging estimates of relative
abundance (to account for the unknown proportion of the
total population that may be roosting outside the known
colony sites). The nocturnal BMP sampling regime
provides a robust basis for monitoring abundance.
Section 2 - Threats and Threat Abatement
Threats
44. Identify past, current and
future threats, to the species
indicating whether they are actual
or potential. For each threat,
describe:
Of the main threatening processes likely to have
contributed to the recent decline of this species, none has
yet been definitively proven. James et al. (2007) provides
a comprehensive account of potential threats and a “threat
assessment matrix” that includes consideration of
plausibility.
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 18 of 33
Phosphate mining has caused loss of about 25% of forest
cover on Christmas Island incrementally since the 1890s.
The areas left after mining are appreciably less suitable for
this species than natural vegetation, so this factor can be
considered to be an actual threat, but it is unlikely to have
been the trigger or primary cause of the recent rapid
decline, which has occurred across the species’ range
(rather than only in mined areas).
Predation may be a major threat to this species,
particularly by feral cats. Tidemann et al. (1994) reported
that Christmas Island flying-foxes were present in 10% of
a large sample of cat guts (although lower proportions
have been recorded in subsequent studies of cat diet on
the Island: van der Lee 1997; Corbett et al. 2003; Algar et
al. 2011). Assuming that prey items may remain in cat
guts for 3 days, and that the population of cats on
Christmas Island is at least 1000 individuals (probably
conservative given about 150 domestic cats, and the high
abundance (no./km of transect) of feral cats reported:
Algar et al. 2011), the Tidemann et al. (1994) incidence of
flying-foxes translates as an annual mortality of at least
1200 flying-foxes. This is clearly unsustainable for a
flying-fox population now estimated as about 1500
individuals (James et al. 2007). This suggest that the
predation rate detected by Tidemann et al. (1994) may
have been unrepresentative, that the number of feral cats
is substantially fewer than 1000 individuals, and/or that
the recently-observed decline in flying-foxes was largely
driven by a period of exceptional predation pressure by
cats, and/or that the recently recorded decreased incidence
of flying-foxes in cat prey items is because of real
reduction in the abundance of flying-foxes.
James et al. (2007) considered a range of other native
(including frigate-birds Fregata spp., nankeen kestrel Falco
cenchroides and Christmas Island goshawk Accipiter
hiogaster natalis) and introduced species (notably the wolf
snake Lycodon aulicus capucinus) were potential predators,
but concluded that these were unlikely to be major threats
to the flying-fox, although noting that the timing of the
observed decline of the flying-fox corresponded (loosely)
with the arrival and increase of the kestrel and wolf snake
(e.g. Smith 1988).
The Christmas Island flying-fox may also have suffered a
reduction in habitat suitability and/or food availability, due
to the broad-scale environmental change associated with
the development of super-colonies of yellow crazy ants.
In addition, roosting flying-foxes may be directly disturbed
by (the partly arboreal) yellow crazy ants.
As with most other island-endemic flying-foxes, the
Christmas Island flying-fox has suffered considerable
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 19 of 33
human predation since the Island’s settlement around
1890. Tidemann (1985) sought to quantify the hunting
pressure during his 1984 study, but obtained little
information. He concluded that “catches of 200 at a time
may not be uncommon. But it is unknown how frequently
hunting is indulged in nor by how many. It seems likely
that it is only an occasional event for most people,
although bats are sometimes procured for sale at the local
market.” It is plausible that “not uncommon” episodes of
“catches of 200” may well have had a substantial impact
on a species with a total population size of about 6000
individuals and a low reproductive output (e.g. Martin and
McIlwee 2002), and hunting pressure has been a major
factor in the decline of island flying-foxes in the Pacific and
Indian Oceans (e.g. Cheke and Dahl 1981). Hunting of
Christmas Island flying-fox is now illegal, but the limited
available evidence suggests that some still occurs (Dennis
2000), although there is no evidence of hunting occurring
today.
Corbett et al. (2003) considered that the major population
reduction observed between Tidemann’s (1984) study and
the next assessment of their status (in 2002) was due to
catastrophic loss associated with a major storm on 26
March 1988. Their speculation follows: “When the cyclonic
winds struck at about 0200h, the strong wind swept many
bats to sea, to the east of the island. All would have had
to maintain flight in strong wind for about 4h until dawn
before they could see properly. Those still in sight of the
island may have made it back, those further away would
have had great difficulty orientating to the island especially
given its relatively small size. It is highly likely that most
of the stranded individuals would have become exhausted
and dropped into the sea and drowned. It is also possible
that many flying foxes died from starvation in the days
following the cyclone because food sources had been
stripped from trees”. Christmas Island was also affected
by Cyclone Rosie in 2008 (Hennicke and Flachsbarth 2009).
Such intense cyclone events are known to have led to
catastrophic population losses of other island flying-fox
species, including in the Pacific and Indian oceans (e.g.
Pierson et al. 1996).
Pollution: Tidemann (1985) reported that one camp (near
Daniel Roux cave) was located beneath the phosphate
drier, and that all vegetation in the camp area was covered
in phosphate dust for much of the year. Phosphate dust
may contain cadmium (but at unrecorded concentrations),
which can have lethal consequences for animal species,
affecting particularly the liver (Burger 2008). It is possible
that roosting flying-foxes may have ingested cadmium
through licking of “dust”-covered fur or consuming dustcovered pollen and/or fruit. This camp is no longer used
(James et al. 2007). [Similarly, a major breeding colony of
the Christmas Island frigatebird in the same location was
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 20 of 33
also abandoned, most likely because of habitat
deterioration due to dust (Stokes 1988; James 2003)].
The drier has been modified over the last decade to reduce
the amount of fugitive dust (Hill and Dunn 2004). Hall et
al. (2011) found cadmium levels of 0.69 mg/kg in their
only sample of Christmas Island flying-fox liver, and stated
that “ongoing toxicological testing is warranted to monitor
environmental exposure of this species to potential toxins”.
It is difficult to contextualise this single value, but it is
notably higher than the range of values (0.06-0.48 mg/kg
for liver) reported for a wide range of wild and laboratory
mammals (including rodents, deer and rabbits) sampled by
Kramarova et al. (2005), who noted that “Ingestion of
even trace quantities of cadmium can affect not only the
physiology and health of individual organisms, but also the
demographics and the distribution of species”. However
the reported value is well under toxic threshold (e.g. 100
ppm in kidney: Larison et al. 2000).
James et al. (2007) listed another possible pollution agent,
poisoning by the insecticide fipronil, used extensively by
managers for the control of yellow crazy ants. However his
assessment of this as a potential cause of decline was that
it was of “low plausibility”, especially given the decline of
the flying fox appears to have preceded the use of Fipronil
in the aerial baiting program for yellow crazy ants of 2002.
Island populations may be particularly prone to the
impacts of newly-arrived disease, and a range of diseases
are of increasing recent profile in Australian mainland
flying-foxes. Limited sampling of Christmas Island flyingfoxes has been conducted (Tidemann 1985; Hall et al.
2011). Hall et al. (2011) recorded coccidia in 4 of 16
faecal samples, and a single incidence of “Ascarid-like
ova”. “This result is very interesting, as internal parasites
from this species have not been reported before despite
Tidemann performing thorough examinations of the gut of
over 100 individuals [in 1984].” “Infection with this
parasite rarely causes clinical disease in adult Pteropus
bats, however upper airway obstruction, ill thrift
demeanour and morbidity have been recorded in greyheaded flying-fox and variable flying-fox pups.” Hall et al.
(2011) also reported that the levels of Alkaline
Phosphatase, Amylase and Lipase were considerably
higher, and Urea (Blood Urea Nitrogen) considerably lower,
in their samples (N=28) of Christmas Island flying-fox
compared to six other flying-fox species for which this
information was available. These parameters are
consistent with some reduced functionality of liver or
pancreas. They also reported no sign of Hendra virus.
Some previously preferred food sources may have been
reduced in recent years. James et al. (2007) note that
management has reduced the abundance of the introduced
umbrella tree Schefflera actinophylla, and post-mine
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 21 of 33
a.
b.
how and where it impacts on
this species;
what its effect has been so far
(indicate whether it is known or
suspected; present supporting
information/research; does it
only affect certain populations);
rehabilitation no longer uses the exotic Jamaican cherry,
and that its abundance along roadsides had been reduced.
The diet of the Christmas Island flying-fox now includes a
considerable proportion of fruits and nectar from
introduced species. It is possible that such food sources
provide less nutrition than the native species that they
have replaced (as has been reported for Pacific Island
flying-foxes: Nelson et al. 2000), but there is no primary
evidence for this for the Christmas Island flying-fox.
see above
Given the panmictic nature of the population on Christmas
Island, and that all individual flying-foxes would move over
the Island over the course of a year, all threats are likely
to affect all individuals in the population.
No threats have been definitively shown to have caused
the population reduction, but a high rate of predation by
cats is indicated by the study of Tidemann et al. 1994),
and relatively high rates (given the small size of the
Island’s flying-fox population) of hunting by humans are
assumed historically (up to the 1980s).
Clearance of native rainforest for mining reduced the
foraging habitat available to this species by about 25%,
with a spike in the extent of clearing between the 1950s
and 1980s (Tidemann 1985).
c.
d.
what is its expected effect in
the future (is there supporting
research/information; is the
threat only suspected; does it
only affect certain populations);
what is the relative
importance or magnitude of
the threat to the species.
45. If not included above, identify
catastrophic threats, i.e. threats
with a low predictability that are
likely to severely affect the species.
Identify the threat, explain its likely
impact and indicate the likelihood of
it occurring (e.g. a drought/cyclone
in the area every 100 years).
46. Identify and explain any
additional biological
characteristics particular to the
species that are threatening to its
survival (e.g. low genetic diversity)?
47. Identify and explain any
quantitative measures or
models that address the probability
The loss of a substantial proportion of the population
directly because of the storm event of March 1988 (and
indirectly to subsequent habitat degradation and reduction
in food availability) concords loosely with the timing of the
decline of this species, but this explanation is speculative.
There is no information available on future changes in
threats, except that cat control and eradication is now
being planned (Algar et al. 2011).
Uncertain.
The incidence of cyclones on Christmas Island has been
very low, but some severe tropical storms (including the
residue of nearby tropical cyclones) have been reported,
including at least two in the last 30 years (e.g. Hennicke
and Flachsbarth 2009). Such storms may lead to direct
mortality for flying-foxes and substantial lag effects
through reduction in forest structure and subsequent
decrease in food resources.
As a resident of a relatively small island, the Christmas
Island flying-fox has probably long maintained a relatively
limited amount of genetic variability.
Nil.
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 22 of 33
of the species’ extinction in the wild
over a particular timeframe.
48. Is there other information
that relates to the survival of this
species that you would like to
address?
The decline of the Christmas Island flying-fox has been
largely concordant with that of the Christmas Island
pipistrelle, and with a range of native Christmas Island
reptile species. It is plausible that the same factors are
involved, to some degree.
Island-endemic flying-foxes have had an unusually high
rate of decline and extinction (Fleming and Racey 2009):
Helgen et al. (2009) lists five extinctions of island-endemic
flying-fox species.
Threat Abatement and Recovery
49. Give an overview of how
broad-scale threats are being
abated/could be abated and other
recovery actions underway/
proposed. Identify who is
undertaking these activities and
how successful the activities have
been to date.
50. For species nominated as
1. Christmas Island National Park. The most recent plan
of management for this park was established in 2002, and
a new plan of management is likely to be released in 2012.
[Parks Australia]
2. A multi-species regional recovery plan (including this
species) will be established in 2012. [Parks Australia]
3. An “expert working group” was established by Minister
Garrett in 2009 to recommend on conservation
management actions and priorities for Christmas Island,
(Beeton et al. 2010).
4. The Australian government has committed long-term
funding for the ongoing control of yellow crazy ants,
consistent with the Threat Abatement Plan.
5. A plan for the control of cats and rats on Christmas
Island (Algar and Johnston 2010) is now being
implemented.
6. There is an ongoing island-wide biodiversity monitoring
program, including this species. [Parks Australia].
n/a
extinct in the wild, provide details
of the locations in which the
species occurs in captivity and
the level of human intervention
required to sustain the species.
Mitigation Approach
51. Describe any mitigation
measures or approaches that
have been developed specifically for
the species at identified locations.
Identify who is undertaking these
activities and how successful the
activities have been to date.
There has been considerable investment in the control of
yellow crazy ants over the period since the late 1990s, and
this program continues. [Parks Australia]
A program to control (or eradicate) feral cats began in
2010, and has to date resulted in the de-sexing of all pet
cats, and killing of more than 200 “wild” cats. [Parks
Australia, in association with the Shire of Christmas Island
and WA Department of Environment and Conservation.]
52. Departmental use only:
Major Studies
53. Identify major studies on the
Significant studies of the species’ ecology and status:
species that might relate to its
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 23 of 33
taxonomy or management.
Andrews, C.W. (ed.) (1900). A monograph of Christmas Island
(Indian Ocean) – physical features and geology, with
descriptions of the fauna and flora by numerous contributors.
British Museum Trustees, London. pp. 1-337.
James, D.J., Dale, G.J., Retallick, K., and Orchard, K. (2007).
Christmas Island Biodiversity Monitoring Programme: Christmas
Island Flying-Fox Pteropus natalis. An assessment of
conservation status and threats. Report to Department of
Finance and Deregulation, and Department of the Environment,
Water, Heritage and the Arts.
Orchard, K. (2006). Christmas Island Flying-fox, Pteropus
melanotus natalis: Initial Survey on Population Status and Threat
Assessment. Unpublished report to Parks Australia North,
Christmas Island.
Tidemann, C.R. (1985). A study of the status, habitat
requirements and management of the two species of bats on
Christmas Island (Indian Ocean). Report to Australian National
Parks and Wildlife Service, Canberra.
Management Documentation
54. Identify key management
documentation available for the
species, e.g. recovery plans,
conservation plans, threat
abatement plans.
Christmas Island National Park Plan of Management
(2002).
Christmas Island “regional recovery plan” (in prep).
Algar, D., and Johnston, M. (2010). Proposed
management plan for cats and black rats on Christmas
Island. (Western Australia Department of Environment
and Conservation, Perth.)
Beeton, B., Burbidge, A., Grigg, G., Harrison, P., How, R.,
Humphreys, B., McKenzie, N., and Woinarski, J. (2010).
Final report of the Christmas Island Expert Working Group
to the Minister for Environment Protection, Heritage and
the Arts.
55. Departmental use only:
Section 3 — Indigenous Cultural Significance
56. Is the species known to have
Indigenous cultural significance to
groups within the Australian
jurisdiction and, if so, to which
Indigenous groups? Are you able to
provide information on the nature
of this significance?
No particular Indigenous or cultural significance –
Christmas Island was uninhabited until the 1890s.
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 24 of 33
Section 4 – References and Reviewers
Notes:
 The opinion of appropriate scientific experts may be cited (with their approval) in
support of a nomination. If this is done the names of the experts, their qualifications
and full contact details must also be provided in the reference list below.
 Please provide copies of key documentation/references used in the nomination
57. Reference list
Algar, D., and Johnston, M. (2010). Proposed management plan for cats and black rats on Christmas
Island. (Western Australia Department of Environment and Conservation, Perth.)
Algar, D., Hilmer, S., Nickels, D., and Nickels, A. (2011). Successful domestic cat neutering: first step
towards eradicating cats on Christmas Island for wildlife protection. Ecological Management and
Restoration 12, 93-101.
Andrews, C.W. (ed.) (1900). A monograph of Christmas Island (Indian Ocean) – physical features
and geology, with descriptions of the fauna and flora by numerous contributors. British Museum
Trustees, London. pp. 1-337.
Beeton, B., Burbidge, A., Grigg, G., Harrison, P., How, R., Humphreys, B., McKenzie, N., and
Woinarski, J. (2010). Final report of the Christmas Island Expert Working Group to the Minister for
Environment Protection, Heritage and the Arts.
Burger J. (2008) Assessment and management of risk to wildlife from cadmium. Science of the Total
Environment 389, 37 - 45.
Cheke, A.S., and Dahl, J.S. (1981). The status of bats on the western Indian Ocean islands with
special reference to Pteropus. Mammalia 45, 205-238.
Corbett, L., Crome, F., and Richards, G. (2003). Fauna survey of Mine lease applications and National
Park reference areas, Christmas Island, August 2002. in Phosphate Resources Ltd 2005. Draft
Environmental Impact Statement for the Proposed Christmas Island Phosphate Mines. Technical
Appendices Vol. 1. Phosphate Resources Ltd.
Cox, P.A., and Elmqvist. (2000). Pollinator extinction in the Pacific islands. Conservation Biology 14,
1237-1239.
Cox, P.A., Elmqvist, T., Pierson, E.D., and Rainey, W.E. (1991). Flying foxes as strong indicators in
South Pacific island ecosystems: a conservation hypothesis. Conservation Biology 5, 448-454.
Dennis, S. (2000). Christmas Island: an anthropological study. (Cambria Press, New York.)
Fleming, T.H., and Racey, P.A. (eds) (2009). Island bats: evolution, ecology, and conservation.
(University of Chicago Press, Chicago.)
Gibson-Hill, C. A. (1947). A note on the mammals of Christmas Island. Bulletin of the Raffles Museum
18, 166-167.
Green, P.T., O’Dowd, D.J., and Lake, P.S. (2001). From resistance to meltdown: secondary invasion of
an island rain forest. In Tropical Ecosystems: Structure, Diversity and Human Welfare. (eds K.N.
Ganeshaiah, R. Uma Shankar, and K.S. Bawa.) pp. 451-455. Proceedings of the International
Conference on Tropical Ecosystems, Bangalore.
Hale, J., and Butcher, R. (2010). Hosnies Spring Ramsar Site: ecological character description.
(Department of Sustainability, Environment, Water, Population and Communities, Canberra.)
Hall, J., Rose, K., Spratt, D., Harlow, P., Donahoe, S., Andrew, P., Field, H., DeJong, C., Smith, C.,
Hyatt, A., and Watson, J. (2011). Assessment of reptile and mammal disease prevalence on Christmas
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 25 of 33
Island. Report to Parks Australia. (Australian Registry of Wildlife Health, Taronga Conservation
Society Australia, Sydney.)
Helgen, K.M., Helgen, L.E., and Wilson, D.E. (2009). Pacific flying foxes (Mammalia: Chiroptera): two
new species of Pteropus from Samoa, probably extinct. American Museum Novitates Number 3646, 137.
Hennicke, J.C., and Flachsbarth, K. (2009). Effects of Cyclone Rosie on breeding red-tailed tropicbirds
Phaethon rubricauda on Christmas Island, Indian Ocean. Marine Ornithology 37, 175-178.
Hill, R.A., and Dunn, A. (2004). National recovery plan for the Christmas Island frigatebird Fregata
andrewsi. (Commonwealth of Australia, Canberra.)
James, D.J. (2003). A Survey of Christmas Island Frigatebird Nests in 2003. Draft report to Parks
Australia North (Christmas Island), Christmas Island, Indian Ocean, and Department of
Environment and Heritage, Canberra.
James, D.J., Dale, G.J., Retallick, K., and Orchard, K. (2007). Christmas Island Biodiversity Monitoring
Programme: Christmas Island Flying-Fox Pteropus natalis. An assessment of conservation status and
threats. Report to Department of Finance and Deregulation, and Department of the Environment,
Water, Heritage and the Arts.
Kramarova, M., Massanyi, P., Jancova, A., Toman, R., Slamecka, J., Tataruch, F., Kovacik, J., Gasparik,
J., Nad, P., Skalicka, M., Korenekova, B., Jurcik, R., Cubon, J., and Hascik, P. (2005). Concentration
of cadmium in the liver and kidneys of some wild and farm animals. Bulletin of the Veterinary Institute
Pulawy 49, 465-469.
Larison J. R., Likens G. E., Fitzpatrick J. W., and Crock J. G. (2000). Cadmium toxicity among wildlife in
the Colorado Rocky Mountains. Nature 406, 181-183.
Martin, L., and McIlwee (2002). The reproductive biology and intrinsic capacity for increase of the
grey-headed flying-fox Pteropus poliocephalus (Megachiroptera), and the implications of culling. In
Managing the grey-headed flying-fox as a threatened species in New South Wales. (eds P. Eby and D.
Lunney.) pp. 91-108. (Royal Zoological Society of New South Wales, Sydney.)
Mickleburgh, S.P., Hutson, A.M., and Racey, P.A. (1992). Old World fruit bats: an action plan for their
conservation. (IUCN, Gland.)
Nelson, S.L., Miller, M.A., Heske, E.J., and Fahey, G.C. (2000). Nutritional consequences of a change
in diet from native to agricultural fruits for the Samoan fruit bat. Ecography 23, 393-401.
O’Dowd, D.J., Green, P.T., and Lake, P.S. (2003). Invasional ‘meltdown’ on an oceanic island. Ecology
Letters 6, 812-817.
Orchard, K. (2006). Christmas Island Flying-fox, Pteropus melanotus natalis: Initial Survey on
Population Status and Threat Assessment. Unpublished report to Parks Australia North, Christmas
Island.
Palmer, C., and Woinarski, J.C.Z. (1999). Seasonal roosts and foraging movements of the black flying
fox Pteropus alecto in the Northern Territory: resource tracking in a landscape mosaic. Wildlife
Research 26, 823-838.
Pierson, E.D., Elmqvist, T., Rainey, W.E., and Cox, P.A. (1996). Effects of tropical cyclonic storms on
flying fox populations on the South pacific Islands of Samoa. Conservation Biology 10, 438-451.
Powell, V.J., and Wehnelt, S.C. (2003). A new estimate of the population size of the critically
endangered Rodrigues fruit bat Pteropus rodricensis. Oryx 37, 353-35.
Schulz, M. (2004). National Recovery Plan for the Christmas Island Shrew Crocidura attenuata trichura.
(Department of the Environment and Heritage, Canberra.)
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 26 of 33
Smith, L.A. (1988). Lycodon aulicus capucinus a colubrid snake introduced to Christmas Island, Indian
Ocean. Records of the Western Australian Museum 14, 251-252.
Stokes, T. (1988). A Review of the Birds of Christmas Island. Australian National Parks & Wildlife
Service Occ. Pap. No. 16. (ANPWS, Canberra.)
Tidemann, C.R. (1985). A study of the status, habitat requirements and management of the two
species of bats on Christmas Island (Indian Ocean). Report to Australian National Parks and Wildlife
Service, Canberra.
Tidemann, C.R. (1987). Notes on the flying-fox, Pteropus melanotus (Chiroptera: Pteropodidae), on
Christmas Island, Indian Ocean. Australian Mammalogy 10, 89-91.
Tidemann, C.R., and Nelson, J.E. (in press). Life expectancy, causes of death and movements of the
grey-headed flying-fox (Pteropus poliocephalus) inferred from banding. Acta Chiropterologica 13, xx.
Tidemann, C.R., and Richards, G.C. (2008). Christmas Island flying-fox Pteropus melanotus. In The
mammals of Australia. Third edition. (eds S. Van Dyck and R. Strahan.) pp. 442-443. (Reed New
Holland, Sydney.)
Tidemann, C.R., Yorkston, H.D., and Russack, A.J. (1994). The diet of feral cats, Felis catus, on
Christmas Island, Indian Ocean. Wildlife Research 21, 279-285.
van der Lee, G. (1997). The status of cats Felis catus and prospects for their control on Christmas
Island. Report to Australian Nature Conservation Agency. (Department of Ecosystem Management,
University of New England, Armadale.)
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 27 of 33
Attachment 1a. Ground counts at known roost sites, pre-2005.
(source: James et al. 2007)
year
site
ETHEL
GRETA
date
count
1984
1985
x/2/1985
date
count
x/3/1984
300
x/9/1984
>1000
HOSNIES
SPRING
date count
McMICKEN/DOLLY
DANIEL ROUX CAVE
MIDDLE POINT
date
date
date
x/3/1984
count
count
count
0
x/3/1984
0
1/6/1984
200
x/9/1984
0
21/9/1984
150
5/9/1984
300
x/11/1984
100
x/3/21985
0
6/3/1985
50
0
31/5/1985
8
17/5/1985
30
5/7/1985
40
24/7/1985
8
2/8/1985
200
4/10/1985
12
30/8/1985
45
18/12/1985
0
30/9/1985
300
1/11/1985
350
12/11/1985
0
5/12/1985
0
9/1/1986
0
9/5/1986
10
7/2/1986
0
6/3/1986
0
1986
x/4/1986
0
12/6/1986
25
15/7/1986
200
8/9/1986
130
Attachment 1b. Ground counts at known roost sites, 2006-2011.
(source Parks Australia data base)
year
site
ETHEL
date
2006
count
GRETA
date
16/06/2006
19/06/2006
20/06/2006
2/07/2006
18/07/2006
24/07/2006
26/07/2006
1/08/2006
9/08/2006
count
276
310
289
280
207
32
35
14
7
HOSNIES SPRING
date
count
5/01/2006
2
16/01/2006
122
23/01/2006
22
21/01/2006
267
6/03/2006
238
27/03/2006
0
26/04/2005
62
9/05/2006
287
6/06/2006
5
McMICKEN/DOLLY
date
count
4/01/2006
12
24/01/2006
13
7/02/2006
83
22/02/2006
127
9/03/2006
224
29/03/2006
138
20/06/2006
37
2/08/2006
68
11/08/2006
23
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 28 of 33
11/08/2006
17/08/2006
21/08/2006
27/09/2006
31/10/2006
19/12/2006
2007 23/05/2007
108
31/01/2007
27/06/2007
0
28/02/2007
25/07/2007
29
24/04/2007
28/09/2007
6
23/05/2007
26/09/2007
0
27/06/2007
29/10/2007
0
25/07/2007
27/11/2007
0
29/08/2007
18/12/2007
0
26/09/2007
29/10/2007
27/11/2007
18/12/2007
2008 30/01/2008
34
30/01/2008
27/02/2008
3
27/02/2008
12
5
35
512
159
49
20/06/2006
18/07/2006
20/07/2006
23/07/2006
26/07/2006
1/08/2006
9/08/2006
11/08/2006
17/08/2006
21/08/2006
27/09/2006
31/10/2006
19/12/2006
10
8
5
0
0
69
3
4
10
0
0
31/01/2007
28/02/2007
24/04/2007
23/05/2007
27/06/2007
25/07/2007
29/08/2007
26/09/2007
29/10/2007
27/11/2007
18/12/2007
0
1
0
9
114
54
0
18
42
0
30/01/2008
27/02/2008
2/04/2008
30/04/2008
28/05/2008
74
0
116
14
9
16/10/2011
15/12/2011
402
39
2/04/2008
0
2/04/2008
30/04/2008
100
30/04/2008
28/05/2008
58
28/05/2008
3/07/2008
0
3/07/2008
30/07/2008
18
30/07/2008
27/08/2008
26
27/08/2008
30/09/2008
0
30/09/2008
26/11/2008
0
26/11/2008
2009 27/02/2009
0
8/04/2009
8/04/2009
0
30/04/2009
4
1
16/7/2009
100
1/02/2010
0
1/02/2010
0
25/05/2010
1
2011 15/12/2011
0
15/12/2011
0
2010
9 17/08/2006
11 27/09/2006
0 31/10/2006
10
15
31
23
32
27
82
91
306
314
62
189
194
86
0
47
212
486
77
291
207
513
140
114
15/12/2011
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 29 of 33
24
Attachment 2a. Exit counts at known roost sites, pre 2005.
(source: James et al. 2007)
year
HOSNIES SPRING
(MARGARET KNOLL)
date
1984
count
x/3/1984
150-200
9/9/1984
1543
17/9/1984
2121
Attachment 2b. Exit counts at known roost sites, 2005-2011.
(source: Parks Australia data base)
year
site
FIELD 25
date
GRETA
(STRONACH
KNOLL)
date
count
count
HOSNIES SPRING
(MARGARET KNOLL)
McMICKEN/DOLLY
date
date
count
count
2005 22/12/2005
41
14/12/2005
95
21/9/2005
32
27/12/2005
7
21/12/2005
0
5/12/2005
148
12/12/2005
139
19/12/2005
6
20/12/2005
7
21/12/2005
1
26/12/2005
36
2/1/2006
21
4/1/2006
14
2006
3/1/2006
17
31/10/2006
18
20/6/2006
51
5/1/2006
6
24/1/2006
3
26/7/2006
17
10/1/2006
29
22/2/2006
217
2/8/2006
12
16/1/2006
58
9/3/2006
152
11/8/2006
0
21/1/2006
141
29/3/2006
163
25/8/2006
3
23/1/2006
9
20/6/2006
180
31/10/2006
131
6/2/2006
10
26/7/2006
221
27/11/2006
150
22/2/2006
141
2/8/2006
168
19/12/2006
255
1/3/2006
90
11/8/2006
92
6/3/2006
27
17/8/2006
106
30/5/2006
84
27/9/2006
670
12/6/2006
86
31/10/2006
693
20/6/2006
100
27/11/2006
386
18/7/2006
80
19/12/2006
247
21/7/2006
105
23/7/2006
54
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 30 of 33
2007
2008
2009
26/7/2006
160
1/8/2006
167
5/8/2006
178
9/8/2006
114
11/8/2006
185
17/8/2006
212
21/8/2006
193
27/9/2006
199
31/10/2006
137
27/11/2006
184
19/12/2006
192
31/1/2007
93
31/1/2007
72
31/1/2007
60
28/2/2007
100
28/2/2007
2
28/2/2007
72
24/4/2007
4
24/4/2007
4
24/4/2007
137
27/6/2007
11
25/5/2007
269
25/5/2007
317
25/7/2007
2
27/6/2007
907
27/6/2007
307
29/8/2007
0
25/7/2007
70
25/7/2007
595
26/9/2007
1
29/8/2007
345
29/8/2007
890
29/10/2007
63
26/9/2007
335
26/9/2007
1895
27/11/2007
95
29/10/2007
267
29/10/2007
578
19/12/2007
184
27/11/2007
147
27/11/2007
206
19/12/2007
95
19/12/2007
450
30/1/2008
27
27/2/2008
47
27/2/2008
420
27/2/2008
20
2/4/2008
8
2/4/2008
137
2/4/2008
7
30/4/2008
77
28/5/2008
908
30/4/2008
0
28/5/2008
19
3/7/2008
331
28/5/2008
0
3/7/2008
39
30/7/2008
428
3/7/2008
0
30/7/2008
39
27/8/2008
812
30/7/2008
3
27/8/2008
106
30/9/2008
368
27/8/2008
4
30/9/2008
336
26/11/2008
267
30/9/2008
9
26/11/2008
56
25/2/2009
29
25/2/2009
3
30/4/2009
0
30/4/2009
153
8/7/2009
4
8/7/2009
6
24/11/2009
177
8/9/2010
2
8/4/2009
76
30/4/2009
287
8/7/2009
405
24/11/2009
614
1/2/2010
307
8/9/2010
112
2010
2011
1/2/2010
16
8/9/2010
20
15/12/2011
6
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 31 of 33
Attachment 3. Records of flying-fox in the biennial Island Wide Survey.
(source: Parks Australia data base).
The extent to which flying-foxes have been included in the recording protocols for these surveys has varied
considerably across surveys. Until the 2009 survey, flying-foxes may have been reported as incidental
records, if observers happened to note them (but they were not included in the list of species that had to
be surveyed at every sampled waypoint). Thereafter, observers were obliged to record their presence or
absence at every one of the ca 1000 waypoints. More thoroughly from 2007 occurrence was also noted
away from fixed waypoints (i.e. when observers were in transit between waypoint sampling).
2001 - recorded at 2 waypoints (no transit info)
2003 - recorded at 25 waypoints (no transit info)
2005 - recorded at 1 waypoint and 7 times in transit
2007 - recorded at 4 waypoints, 14 times in transit
2009 - recorded at 53 waypoints, 10 times in transit
2011 - recorded at 89 waypoints, 48 times in transit
Note that the tallies for 2003 and 2005 are inconsistent with those reported in James et al. (2007), who
noted that "The 2003 IWS recorded 20 P. natalis and the 2005 IWS recorded 26 from c. 1000 survey points.
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 32 of 33
Figure 1. Location of known colony sites of Christmas Island flying-fox (large blue
circles), broad habitat types, national park boundary, cleared areas. (from James et
al. 2007).
Christmas Island flying-fox (Pteropus melanotus natalis) Nomination — Page 33 of 33