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This is a copy of a recent submission for publication. The results of the editing process have changed the paper to the point where it will be different enough from its current form that I feel comfortable in posting it on Biokryptos. I omitted figures in the paper which appear in a previous post on the same subject. Enjoy!
Abstract
The
Guiana Highlands of northern South America contain a unique ecoregion
known as Pantepui, a biogeographic unit composed of topographically
semi-isolated plateaus known as tepuis, which are host to a high
level of endemic vascular plants. The current scholarly consensus
defines the fauna of Pantepui as being being primarily composed of
partially endemic herpetofauna, some endemic avifauna, no endemic
mammals and depauperate of >5 kg wide ranging lowland mammals.
Despite this, periodic sightings of wide ranging lowland Guiana
Shield mammals have been reported from the summits of the eastern
sector of Pantepui since initial exploration in the 1930s to the
current date: the presence of which represents an epistemological
discontinuity in the scientific knowledge of Pantepui faunal
distribution. In an attempt to resolve this discontinuity a camera
trapping pilot study was initiated in January 2012 on the summit of
Auyan Tepui. The camera traps recorded images of the crab-eating fox
Cerdocyon thous thous on the
southern slopes of Auyan Tepui at 1010 metres. This pilot study is
the first instance of camera trapping on a tepui summit, and confirms
that wide ranging Guiana Shield hypocarnivorous mesopredators are
able to access tepui talus slopes and by extension tepui summits.
The range, distribution, and population dynamics of C. t.
thous in the Pantepui remains
unclear, as does its interaction with tepui summit biota.
Establishing the interactions between lowland organisms and tepui
summit biota has important immediate conservation implications, as
anthropgenic climate change is predicted to result in a >80%
habitat loss in the Pantepui by 2100 C.E. The 2012 camera trapping
pilot study indicates that the use of camera trapping surveys can
contribute positively to future conservation efforts and scientific
research in the Pantepui.
Article
INTRODUCTION
The
tepuis of northeastern South America are topographically isolated
mesas comprised of uplifted Precambrian rock, which compose a 5,000
square kilometre biogeographical region known as the Pantepui (Huber
1988, McDiamid and Donnelly 2005) located in the Guiana Highlands
(GH) situated on a craton known as the Guiana Shield (GS). The
region is host to a high level of endemic vascular plants; 65%
endemic to the GS, 33% are endemic to the GH, and 25% of organisms
are endemic to individual tepui summits (Nogue et al. 2009).
Pantepui is considered to be an important element for both the
current and future biodiversity of northern South America (Rull 2005,
Vegas-Vilarrubia et al. 2012). Conservation of the GS and the GH
vary from country to country, though the region is sparsely populated
and considered to be pristine. Venezuela has conserved some 30% of
the GS in its borders in a variety of parks and national monuments,
including Canaima National Park. Canaima is a 30,000 square
kilometre UNESCO World Heritage Site which hosts ecotourism and acts
as watershed for the Guri Dam (Gutman 2002, Hallowell and Reynolds
2005). Canaima contains tepuis classified by Huber as belonging to
the Eastern Sector of Pantepui, which comprises Roraima, Auyan Tepui
and the Chimanta Massif as well as 14 other smaller tepuis (Huber
1988, Berry and Huber 1995). Surveying of the summits of the tepuis
has been conducted periodically by major universities and scientific
institutions since their formal discovery; however long term
expeditionary research is lacking (Myers 2000, Nogue et al. 2009).
The known fauna of the tepui summits is composed almost exclusively
of birds and reptiles, and the herpetofauna has a high degree of
endemicity (Senaris and MacCulloch 2005, De Avila Pires 2005),
although the paleofaunal origin theory for tepui faunal distribution
has been largely disproved (Rodder et al. 2010, Salerno et al. 2012).
No endemic mammal species have been observed or catalogued on
tepui summits; even the Roraima mouse Podoxymys roraimae is
considered to be present outside of Roraima where it was originally
catalogued (Linares 1998, Patton et al. 2012). Lowland organisms
which reside in the GH or were intermittently reported on the tepui
summits tend to be members of wide ranging GS clads, as larger
organisms in the five kg and above range have not been recorded as
being consistently present on any tepui summit (Huber 1988, Lim et
al. 2005). However, recent articles indicate that the brown-nosed
coati Nasua nasua vittata is present on the summits of
Roraima and individual tepuis in the Chimanta Massif (Havelkovaet al.
2006, Robvinskyet al. 2007), and some lowland mammals have been
observed rarely on the tepui summits (Tate 1939, Huber 1988, Ochoa et
al 1993). The extent to which larger mammals and members of
carnivora are present on the summits and talus slopes of the tepuis
has never been assessed due to the lack of long term field studies on
the fauna of the tepui ecosystems. This lack of long duration field
work has produced a knowledge gap concerning the faunal composition
of the tepui summits, in which the influx of wide ranging lowland GS
organisms is unknown.
In
an effort to close this knowledge gap, a camera trapping pilot study
was initiated from January 6th to January 13th
2012, conducted by an expeditionary team travelling along a path to
the summit of Auyan Tepui colloquially referred to as the “Laime
Trail”. With a summit area of nearly 700 square kilometres and a
talus slope area of 200 square kilometres, Auyan is the largest
tepui in terms of continuous summit area, (Huber 1988) and may hold
the highest biological carrying capacity of any tepui (implied by
species diversity; see Jaffe et al. 1993, Myers and Donnely 2005).
Camera trapping was selected as the most effective methodology to
investigate the presence of larger lowland mammals on the tepui
summits, based on the methods' proven success in capturing cryptic
and/or elusive species, as well as species with low population
densities (Carbone et al. 2001, Silveria et al. 2003, Srbek-Araujo
and Chiarello 2005, Rovero et al. 2008, Tobler et al. 2008).
Survey
area
Satellite image of Auyan Tepui showing camera trapping locations on the
'Laime Trail'; southern portion of Auyan Tepui (yellow pins denote
camera trap/camp locations). Pin # 1 is Campo Guayaraca, 1,010 metres in
located in mid-altitude mountain forest. Pin no. 2 is camp Peñón 1,838
metres altitude, pin # 3 marks camp Naranja 2,161 metres altitude.
Image obtained courtesy of Google Earth (c) Google 2012. Satellite image
taken by U.S.G.S. 12/31/1969
The
survey area is the southern talus slopes and summit of Auyan Tepui (N
5°55' W 62°32'), along the Laime Trail, which is roughly identical
to the trail used by the first scientific expedition to the summit of
Auyan Tepui led by G. H. H. Tate in 1937-38 (Tate 1938, Chapman
1939). This area also serves as the primary point of entry for
tourist expeditions to the summit. Camera traps were placed at Campo
Guayaraca, (1,010 metres altitude, N 5º 41.084' & W62º 31.483)
on the tepui talus slopes, and on
the tepui summit at Peñón
(1,838 metres altitude, N
5º
44.665'
&
W62º
32.452)
and Naranja (2,161 metres altitude,N
5º
46.415'
&
W62º
31.969').
The ecosystems encountered on the trail and camera trap locations
varied from mountain forests to rocky tepui summit meadows dominated
by herbaceous assemblages (fig. 1).
METHOD
The
pilot study methodology was the nocturnal utilization of camera traps
at multiple camp locations as the expedition proceeded along the
Laime Trail on the summit of Auyan Tepui. The expedition team also
performed an ad hoc transect survey of the south of Auyan Tepui, and
reconnaissance of locations for future camera trapping exercises was
undertaken. Two Moultrie D55 IR GameSpy (Moultrie, Alabama, U.S.A)
camera traps were utilized, using different settings and designated
Biokpt 1 and Biokpt 2. Biokpt 1 was set up to include still shots
and five second videos at a low resolution (1280 x 969; 1.3 mega
pixel photographs, 320 x 240 video segments); Biokpt 2 was configured
to take multiple photographs at medium resolution (2048 x 1536; 3.2
mega pixels). The info strips and infrared flash were set to “on”;
all other functions were left on the default settings. The traps
were baited with leftover food scraps from the expedition team, and
two cameras were positioned in close proximity to obtain optimum
images of animals attracted to this bait. Cameras were located as
far away from camp as feasible, in practicality between 10 and 50
metres. The cameras were placed approximately 60 centimetres above
ground, and were attached to trees along natural trails using straps
provided with the cameras or placed on rocks when trees or bushes
were not available. Altitude and GPS coordinates of the camera trap
locations were recorded (fig. 2 and 3).
Camera trap placement at Campo Guayaraca, 1,010 metres in mountain forest. Camera s were placed facing baited capture zone.
Camera trap placement on the summit of Auyan Tepui at Pemon 1,838 metres
on rocky surfaces amid tepui meadows. Suitable trees for camera
attachment were not found.
RESULTS
Each
camera was operational for 166 hours in the field, producing 332
camera hours, or approximately 13.8 camera days (a “camera day”
is the number of cameras multiplied by the number of days they are
operational). At Campo Guayaraca, the camera traps recorded images
of a crab-eating fox (fig 4, video 1), Cerdocyon thous thous 50
metres from the camp in an upland to low-mountain forested
environment. Fox subspecies classification is based upon the
physical features of the fox, as well as the known distribution of
foxes in this region (Bisbal 1988, Hallowell and Reynolds 2005,
Tchaick et al. 2006). A medium sized canid, Cerdocyon thous
weighs on average 5-7 kg, and is identifiable by a moderately
bushy tail with a black or dark tip, narrow pointed head, dark pelage
from the dorsum to the midline, and light coloured ventral pelage,
although significant pelage colour variation is known (Berta 1982).
Two subspecies are known in Venezuela; C. t. aquilis in the
eastern portion of the country, and the GS subspecies recorded in
this camera-trapping study C. t. thous (Bishal 1988). All
five subspecies of Cerdocyon thous are classified as stable
through their range, and have a IUCN classification of Least Concern
(LC), though all subspecies are subject to variable rates of hunting
(IUCN 2012). From the images recorded in the camera trap video
sequences, it seems as though the fox is startled by the infrared
flash of the cameras, but is not engaged in trap avoidance behaviour;
a concern in camera trap studies (Sequin et al. 2003). Vertebrates
sighted during the transect survey are: one lizard, one frog and
several small rodents at Naranja camp (2,161 metres), one frog at
Guayaraca (1,010 meters). Species identification for these animals
are were not stated (Pomares, personal communication).
DISCUSSION
There
exists no study of the general population dynamics for crab eating
foxes in the Guiana Highlands, and the total population of C.
thous across South America can only be inferred from studies on
localized populations (Tchaick et al. 2009). There are numerous
studies involving camera trapping that did included C. thous
captures that were conducted across various ecosystems across South
America. In the Bolivian Chaco, four years of camera trapping
(2001-2005) resulted in 215 photos of Cerdocyon thous (Maffei
et al. 2007). A study in the Emas National Park in Brazil, conducted
over the span of one year using eighty two camera traps, produced a
capture rate of 93 captures out of 157968 camera trap hours, with a
calculated photographic rate defined in photographs/hour at between
0.000106 to 0.000980 depending on habitat (Jacomo et al. 2004).
Camera trapping the Parque Estadual Carlos Botelho using seven
to ten camera traps over 922 days produced 17 photos of Cerdocyon
thous, with the time from set up to initial capture being 31 days
(Beisiegel 2009). The 2012 Auyan Tepui pilot study capture per
camera hour rate is comparatively high at between 0.0421 and 0.0361
for the two cameras with set-up to capture being a single day;
however the brevity of the study makes any statistical comparison
with other studies problematic. Only a longer study or series of
short term studies in the Pantepui region would yield enough data to
make valid and useful comparisons. Beyond brevity, the camera
trapping study was hampered by constant rain which prevented camera
set-up more than 50 meters from camp sites, a lack of suitable trap
sites and problematic trap set up on tepui summit meadows. In
future efforts, pre-built structures must be made to attach the
cameras to, as tepui meadows do not contain sufficiently thick trees
to affix the traps. It is unfortunate this is the first instance of
camera trapping and investigation into the fox population of the
tepui slopes; a contemporary analysis would provide a baseline for
comparison.
Despite
the knowledge gap regarding the distribution of larger carnivores on
the tepui summits, C.
t. thous
has been noted as being a resident of the Auyan Tepui by G.H.H. Tate
(Tate 1939), though no collection altitude is listed.
Tate
made several anatomical observations comparing the Auyan Tepui
Cerdocyon
thous
specimens with those found in the Cotiga savannah and the Orinoco
river basin. The two groups differ in their auditory bullae, the
proportions of the basiocciptial, and in their dentition, in which
Auyan tepui foxes have “small teeth” (Tate 1939). With regard to
the external feature of Cerdocyon
thous,
Tate remarks that the Auyan tepui foxes possess smaller short haired
tails with black markings limited to the tip of the tail (Tate 1939).
Tate asserts that Guiana Highlands C.
t. thous
can be differentiated by these features, representing a transitional
form between the northern Brazilian foxes and those found in the
Venezuelan llanos. Although this camera trapping experiment did not
obtain enough information to verify Tate's observations regarding the
derivation of C.
t. thous
across northern South America, it does confirm his observations
regarding the distribution of foxes into the upper elevations of
Auyan Tepui. Recent phylogenetic analysis of the mitochondrial DNA
of Cerdocyon
thous
supports a differentiation into two phylogeographic clades, where C.
thous
in the Guyanas and south-eastern Amazonia is present in a “mixture
zone between the two major phylogeographic clades” (Tchaicka et al.
2006). One theory presented in Tchaicka et al. (2006) for the
differentiation of C.
thous
into two clades is the possible origin of its ancestral population in
Venezuela and Guyana. If this is the case, C.
t. thous
would have a long history in the GH, and its interaction with tepui
summit biota should be analysed in a paleoecological perspective
(Rull 2010). Phylogenetic analysis places the differentiation of the
two major C.
thous
clades at between 600 kya and 400 kya, when glacial conditions
dominated. Glacial conditions allowed for the downward displacement
of tepui flora while paramo-like floral assemblages dominated the
summits. This placed tepui-like ecosystems 1,000 metres below their
current levels, in contact with the lowlands (Rull 2005). Climate
Envelope Distribution Models projected the Last Glacial Maximum (21
kya) expansion of tepui climate envelopes far beyond their current
range; corresponding to modern upland regions in all of Estado
Bolivar in Venezuela, and in Guyana up to approximately 100
kilometres from the coast (Rödder et al 2010). As C.
thous
dispersed into South America during the Pleistocene, the majority of
its evolutionary history in the G.H. would have occurred during these
glacial conditions, allowing C.
thous
subspecies to interact with tepui-like biota for extended periods of
time. The presence of tepui-like ecosystems in the lowlands during
glacial periods may therefore predispose certain GS organisms like C.
t. thous
to ranging into current tepui summits, though topographic and
biological constraints on individual tepuis may be a limiting factor.
Tate's expeditionary work in the GH failed to produce evidence of
foxes on Mt. Duida, and upon further investigation he confirmed with
the indigenous people that C.
t. thous
is unknown in the region (Tate 1939). One possible explanation is
that that higher elevation tepuis do not maintain the same levels of
ecosystem diversity and carrying capacity, representing a barrier to
range expansion. If this is the case, then the distribution of C.
t. thous
in the Pantepui region would be predicted to include the Chimanta
Massif, and other large low elevation, floristically diverse tepuis.
Establishing the range, population dynamics and niche of C.
t. thous
on the tepui talus slopes and summits is crucial for understanding
the current and future ecosystem dynamics of the Pantepui. C.
t. thous is
a potential seed disperser, and its gut may encourage the germination
of certain plant seeds, a phenomena also observed in N.
nasua
( Alves-Costa 2007, João Vasconcellos-Neto et al. 2009, Cazetta et
al. 2009,). Seed dispersal mechanisms are not well known in the GH,
and tepui floral dispersal capabilities are considered to be minimal
(Rull 2010). C.
t. thous
and N.
nausa
may change the distribution of current and future floral assemblages
on the tepui summits, introducing non-endemic plant species by
acting as seed dispersers (Nathan et al. 2008, Thuiller et al. 2008).
This possibility is pertinent given the dramatic effects
anthropogenic climate change will have on the distributions of future
tepui ecosystems. Analysis of the predicted future distribution of
tepui vascular plants using Altitudinal Range Displacement, Species
Area Relationships, and spatial analysis indicates that some 80% of
tepui habitats will be lost to upward vertical displacement,
producing 100% extinction in some tepuis and 34-57% on the least
threatened tepuis by 2100 (Vegas-Vilrrubia et al. 2012). This is a
conservative estimate, as remaining habitat area will be severely
restricted and spatially disjointed, leading to unpredictable
interactions of floral and faunal assemblages in refuge areas. How
anthropogenic climate change will effect the range, population
dynamics, and behaviour of C.
t. thous
in the GH is unknown at this time, as is the impact of seed dispersal
from lowland animals on the tepui summits under global warming
conditions.
From
an epistemological stand point, the photographic capture of C.
thous is somewhat surprising, as is this animals lack of
documentation on the tepui summits or talus slopes outside of the
1939 publication of Mammals of the Guiana Highlands. It could be
that the absence of C. t. thous on the summit is the result of
a sampling error; C. t. thous is mostly active during the
night and at dawn, and therefore unlikely to be encountered during a
transect walk or under the usual conditions of daytime scientific
field activity. In this case, when a survey methodology was used
that was biased towards nocturnal organisms, (ie nocturnal camera
trapping), the presence C. t. thous was recorded successfully.
In all likelihood this nocturnal carnivore would not have been
recorded without the camera trapping experiment, as it was not
observed by the expedition team during the transect survey.
The
epistemic discontinuity of GH fauna distribution is addressed in
Havelkova et al. (2006) and Robivinsky et al. (2007) with their
observations of tepui summit coati distribution. The authors
concluded that the presence of coatis on Roraima Tepui and the
Chimanta Massif is standard for the distribution of coatis in the GH.
Their conclusion is based on reviews of published expeditionary
literature regarding the Chimanta Massif and the falsification of the
hypothesis that tourist activity entices coatis to the summits by
providing food sources for these animals to scavenge. Further
support of the conclusions of Havelkova et al. (2006) and Robvinsky
et al. (2007) can be found in video and photographic evidence of
coatis on the summit of Auyan Tepui recorded in video documentary
form in the late 1980s by Terramar expedition teams and in 2008 with
photographs taken on the summit by Alberto Pomares, who assisted in
the 2012 Auyan Tepui camera trapping pilot study (Artz and Kirchner
1991, Barkoczy 2009, Alberto Pomares; personal communication 2011).
These sightings verify the observed distribution of coatis in the GH
by Tate during the 1937-38 Phelps expedition, although they do not
necessarily support Tates' classification of a coati subspecies Nasua
dichromatica as distinct from Nasua nasua vittata in in
this area (Tate 1939). Both N. n. vittata and C. t. thous
are hypocarnivouous mesopredators (Aguiar et al. 2011). This trait
is important to the analysis of carnivora on the tepui summits, as
poor soils and continual erosion restrict vegetational growth in
tepui ecosystems and would limit range expansion of hypercarnivorous
species in the GH (Forget and Hammond 2005).
Conclusion
The
verification of C. t. thous on the talus slopes of Auyan Tepui
raises questions regarding the paleodistribution, current range and
ecological role of this canid in the GH and Pantepui. It is unknown
how C. t. thous interacted with Pleistocene tepui ecosystems,
and how this interaction may effect the current and future
distribution of this animal into the tepui slopes and summits.
Future camera trapping on the slopes and summit of the Auyan Tepui
and the eastern sector tepuis of Venezuela would be useful in
deducing the sum total biodiversity of the tepui summits, bearing in
mind that camera trapping results would be biased toward capturing
images of larger bodied endothermic vertebrates. Such a camera
trapping survey would require mapping analysis of Auyan Tepui
focusing on both key regions of interest and entrance points along
the talus slopes, an increase in both the number of camera traps used
and and their duration of time in the field, and proper post camera
trapping data analysis, following the Tropical Ecology And Monitoring
Network protocols (TEAM Network 2011). Finally, survey gap analysis
tools would be helpful in analysing expeditionary work in the
Pantepui, and perhaps even on individual tepui summits (Funk et al.
2005). Survey gap analysis, GIS analysis, and target oriented camera
trapping would make future research and expeditionary work more cost
efficient, and would help to identify and catalogue the Pantepui
organisms before climate change alters this environment permanently.
Acknowledgements
I
am deeply indebted to the entire expedition crew for the realization
of my pilot study; Alberto Pomares, Vittorio Assandria, Daniel
Abgrall, Cedrig Abgrall, Dr. Douglas Olivares, Nelson Gonzalez,
Richard Dittmar, Ana Cristina Fernandez, Dr. Carlos Acevedo, and Paul
Stanley. I would also like to especially thank the Pemon guides who
assisted with the completion of the camera trap: Santos Ugarte (the
principle guide), Arturo Berti (Guide and Camera Trap assistant) and
Nixson (Camera trap assistant).
Literature
cited
Aguiar,
L.M, Moro-Rios R.F, Silvestre, T., Silva-Pereira J.E., Bilski, D.R.,
Passos F.C., Sekiama M.L, Rocha, V.J. 2011. Diet of brown-nosed
coatis and crab-eating raccoons from a mosaic landscape with exotic
plantations in southern Brazil. Studies on Neotropical Fauna and
Environment 40:153-161.
Barkoczy,
L. 2009. Globalzing a lost word: beauty or benefit, what drives
conservation? The International Relations Journal San
Francisco State University 28:60-79
Berry,
P.E., Huber, O., Holst, B.K. 1995. Floristic analysis and
phytogeography. Pp. 161 – 191 in Berry, P.E., Holst, B.K.,
Yatskievych, K. (eds.) Flora of the Venezuelan Guayana Volume 1
Missouri Botanical Garden Press, St. Louis Missouri.
Berta
A,. 1982. Cerdocyon thous. Mammlian Species 186:1-4
Bisbal,
Francisco J. 1988. A taxonomic study of the crab eating fox,
Cerdocyon thous, in Venezuela. Mammalia 52:181-186
Carbone,
C., Christie, S., Conforti, K., Coulson, T., Franklin, N., Ginsberg
J.R., Griffiths, M., Holden J., Kawanishi, K., Kinnaird, M., Laidlaw,
R., Lynam, A., Macdonald, D. W., Martyr, D., Mcdougal, C., Nath, L.,
Obrien, T. O., Wan Shahruddin, W. N. 2001. The use of photographic
rates to estimate densities of tigers and other cryptic mammals.
Animal Conservation 4:75-79
Cazetta
E., Galetti M. 2009. The Crab-eating Fox (Cerdocyon thous) as a
secondary seed disperser of Eugenia umbelliflera (Myrtaceae) in a
Restinga forest of southeastern Brazil. Biota Neotropica 9:2
271-274
Alves-Costa
C. P. 2007. Seed dispersal services by coatis (Nasua nasua,
Procyonidae) and their redundancy with other frugivores in
southeastern Brazil. Acta Ecologica 32:77-92
Chapman,
F. M. 1939. Upper zonal birds of Mt. Auyan-Tepui. American
Museum Noviates. 1051:1-15
Courtenay,
O., Maffei, L. 2008. Cerdocyon
thous.
In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.1.
<www.iucnredlist.org>.
Downloaded on 24 September 2012.
De
Avila Pires, T.C.S. Reptiles. pp 25-40 in Hallowell, T., Reynolds,
R.P., eds 2005 Checklist of the Terrestrial Vertebrates of the Guiana
Shield. Bulletin of the Biological society of Washington
13:1-98
Forget,
P., Hammond, D.S. 2005. Rainforest vertebrates and food plant
diversity in the Guiana Shield. Pp 233-295 in Hammond, D.S. (eds.)
Tropical Forests of the Guiana Shield; Ancient forests in a modern
world. Cabi international Publishing, Cambridge M.A. USA.
Gutman,
P. 2002. Putting a Price Tag on Conservation: Cost Benefit Analysis
of Venezuela's National Parks. Journal of Latin American Studies.
34:43-70
Hallowell,
T., Reynolds, R.P. Introduction. Pp. 1-6 in Hallowell, T., Reynolds,
R.P., eds 2005 Checklist of the Terrestrial Vertebrates of the Guiana
Shield. Bulletin of the Biological society of Washington
13:1-98
Havelková
P., Robovský J., Audy M., De Pascual, A.D. 2006.
Brown-nosed coati (Nasua nasua vittata) on the Roraima tepui
(Carnivora: Procyonidae). Lynx (Praha) 37: 123–130
Huber,
O. 1988. Guyana Highlands versus Guyana Lowlands, a reappraisal.
Taxon. 37: 595-614.
Jacomo,
A.T.A.; Silveria, L. Diniz-Filoh, J.A.F. 2004. Niche separation
between the manned wolf (Chrysocyon brachyurus), the
crab-eating fox (Dusicyon thous) and the hoary fox (Dusicyon
vetulus) in central Brazil. Journal of Zoology 262:99-106
Jaffe
K., Lattke J., Perez-Hernandez R. 1993. Ants on the tepuies of the
Guiana Shield: a zoogeographic study. Ecotropicos 6:22-29
Lim, B.K., Engstrim,
M.D., Ochoa, J.G. 2005. Mammals. Pp 77-92 in Hallowell, T., Reynolds,
R.P., (eds.) Checklist of the Terrestrial Vertebrates of the Guiana
Shield. Bulletin of the Biological society of Washington 13:
1-98
Linares, O.J. 1998.
Mamiferos de Venezuela.
Sociedad Conservacionista Audubon de Venezuela & British
Petroleum, Caracas Venezuela.
Maffei, L., Paredes R.,
Segundo, A. Noss, A., 2007. Home range and activity of two sympatric
fox species in the Bolivian Dry Chaco. Canid News 10.4
URL.http://www.canids.org/canidnews/10/
Sympatric_foxes_in_Bolivia.pdf.
McDiarmid, R. W and
Donnelly, M.A. 2005 . The herpetofauna of the Guayana Highlands:
amphibians and reptiles of the Lost World. Pp. 461–560 in M. A.
Donnelly, B. I. Crother, C. Guyer, M. H. Wake, and M. E. White
(eds.), Ecology and Evolution in the Tropics: A Herpetological
Perspective. University of Chicago Press, Chicago, Illinois.
Myers,
C.W. 2000. A history of herpetology at the American Museum of Natural
History. Bulletin of the American Museum of Natural History
252:1-232
Nathan,
R., Shurr, F. M., Spiegel, O., Steinitz, O., Trakhtenbrot, A., Tsoar,
A. 2008. Mechanisms of long distance seed dispersal. Trends in
Ecology and Evolution 23:638-647
Nogue,
S., Rull, V., Vegas-Vilarrubia T. 2009. Modeling biological diversity
loss by global warming on Pantepui, northern South America: projected
upward migration and potential habitat loss. Climate Change
94:77-85.
Ochoa-G.,
J., Molina, C., Giner, S. 1993. Inventario y estudio comunitario de
los mamíferos del Parque Nacional Canaima, con una lista de las
especies registradas para la Guayana venezolana. Acta Científica
Venezolana 44: 245– 262
Robovsky,
J., Audy, M., Schlogl, J., Diaz Pascual, A., Havelkova, O. 2007.
Additional report of the Brown-nosed Coati (Nasua nasua vittata) on
the tepuis – the Chimanta Massif, Churi Tepui, Venezuela. Lynx
(Praha) 38: 115-117
Rödder. D., Schlüter,
A., Stefan Lötters, S. 2010. Is the 'Lost World' Lost? High Endemism
of Amphibians and Reptiles on the South American Tepuis in a Changing
Climate. Pp 401-416 in Habel, J.C., & T. Assmann (eds.) Surviving
on a changing climate - phylogeography and conservation of relict
species. Springer, Heidelberg.
Rovero,
F., Rathbun, G. B., Perkin, A., Jones, T., Ribble, D. O., Leonard,
C., Mwakisoma, R. R. , Doggart, N. 2008. A new species of giant sengi
or elephant-shrew (genus Rhynchocyon)
highlights the exceptional biodiversity of the Udzungwa Mountains of
Tanzania.
Journal of Zoology
274:126–133.
Rull,
V. 2005. Biotic diversification in the Guayana Highlands: a proposal.
Journal of Biogeography 32:921-927
Rull,
V. 2010. Ecology and Paleoecology: Two Approaches, one Objective.
Open Ecology Journal 3:1-5
Salerno,
P. E., Ron, S. R., Señaris, J. C., Rojas-Runjaic, F. J. M., Noonan,
B. P. and Cannatella, D. C. 2012. Ancient tepui summits harbor young
rather than old lineages of endemic frogs. Evolution
66:3,000-3,013
Senaris,
C.J., and MacCulloch, R. 2005. Amphibians. Pp 9-23 in Hallowell, T.,
Reynolds, R.P. (eds.) Checklist of the Terrestrial Vertebrates of the
Guiana Shield Bulletin of the Biological society of Washington
13:1-98
Séquin E.S., Jaeger, M.M., Brussard, P.F., Barrett, R.H. 2003. Wariness of coyotes to camera traps relative to social status and territory boundaries. Canadian Journal of Zoology 81:2015-2025
Silveria.
L., Jacomo, A. T. A, Diniz-Filho, A. F. 2003. Camera trap, line
transect census and track surveys: a comparative evaluation
Biological Conservation 114:351-355
Tate,
G. H. H. 1938. Auyantepui, Notes on the Phelps Expedition.
Geographical Review 28:452-474
Tate,
G.H. H. 1939. Mammals of the Guiana Region. Bulletin of the
American Museum of Natural History 76:15 1-229
TEAM
Network. 2011. Terrestrial Vertebrate Protocol Implementation Manual,
v. 3.1. Tropical Ecology, Assessment and Monitoring Network, Center
for Applied Biodiversity Science, Conservation International,
Arlington, VA, USA .
http://www.teamnetwork.org/protocols/bio/terrestrial-vertebrate
Terra-X
episode 33 “Inslen uber dem regenwald- die suche nach dem saurier”
1991. Dir. Artz, V., Kirchner, G. GEO-Film , ZDF
Thuiller,
W., Albert, C., Araujo, M.B., Berry, P.M., Caberza, M., Guisan, A.,
Hickler, T., Midgley, G.F., Paterson, J., F.M., Sykes, M.T.,
Zimmermann, N. E. 2008. Predicting global change impacts on plant
species' distributions: Future challenges. Perspectives in Plant
Ecology, Evolution and Systematics 9:137-152
Tobler,
M. W., Carrillo-Percastegui, S. E., Leite Pitman, R., Mares, R.,
Powell, G. 2008. An evaluation of camera traps for inventorying
large-and medium-sized terrestrial rain forest mammals. Animal
Conservation 11:169-178
Vasconcellos-Neto, J.,
Barbosa de Albuquerque, L.,
Silva, W.R. 2009. Seed dispersal of Solanum thomasiifolium
Sendtner (Solanaceae) in the Linhares Forest, Espírito Santo
state. Acta Botanica Brasilica. 23: 1171-1179.
Vegas-Vilarrubia,
T., Nogue S., Rull V. 2012. Global warming, habitat shifts and
potential refugia for biodiversity conservation in the neotropical
Guayana Highlands. Biological Conservation 15: 159-168.
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