Abstracts available here - Society for Conservation Biology

25th International Congress for Conservation Biology • Auckland, New Zealand • 5-9 December 2011
or amphibians. Controlling for taxonomy, high risk species were not
involved in larger (i.e. number of individuals) incidents than lower risk
species. Across years the number of novel exotic vertebrate species detected
‘at large’ in Australia has significantly increased. We strongly recommend
a nationally coordinated framework for data collection, and data sharing
among agencies. We present a minimum framework, for the future
collection of inter-agency data, necessary to monitor the ongoing risk of
pest incursions and that is applicable to any region within a transport hub.
2011-12-08 18:30 Variations in insect communities along a
conservation area- agricultural gradient in Swaziland
Catanach, T.A.*, Texas A&M University; McCleery, R.A.,
University of Florida; Silvy, N.J., Texas A&M University;
We examined changes in insect communities along a gradient in 4 transects
in areas under intensive sugarcane production in Swaziland. Three
transects started at the interface between a conservation area and extended
375m into the sugarcane while the last transect originated at the interface
between sugarcane and a small town. Insects were collected at 5 points
(0, 75, 150, 225, 375m) along the gradient using light traps and yellow
pan traps, then identified to lowest taxonomic unit. These were grouped
into 3 classes- beneficial (parasitoids, predators), pests (groups that transmit
plant diseases or cause damage), and neither based on life history. We
examined community composition of insects across site and gradient and
found community composition was different across the gradient. Beneficial
insects were lowest at the 375m point, while the other classes were site
dependant. Insects were most abundant at the site bordering the most
degraded conservation area. Conservation areas have effects on bordering
agricultural systems and understanding these effects on invertebrate
communities can allow producers to make more informed decisions about
pest management in these regions. Determining these communities, their
response to the gradient, and differences between types of conservation
areas is the first step in this process.
2011-12-07 17:15 Odours of mass deception – reducing the impact of
alien predators using chemical camouflage
Catherine J Price*, University of NSW; Peter B Banks, University
of Sydney;
Mammalian predators that have established alien populations pose a
persistent threat to global biodiversity, particularly predatory rodents and
mustelids. To find prey, mammalian predators primarily use olfaction,
which provides contextual information on relative prey abundance and
quality within natural environments. Yet despite the importance for
predicting and manipulating prey vulnerability, olfactory-driven behaviours
of alien predators are not well understood. To address this gap, we used
‘chemical camouflage’ techniques to investigate the influence of spatial
and temporal variation in prey odour cues on foraging behaviours of three
alien predators in order to understand how odours might be manipulated
to alter predator success. Wild caught house mice Mus musculus showed
rapid improvements in foraging success when searching for high value prey
regardless of the odour background, but were unable to improve when
searching for lower value prey against a uniform odour background. For
stoats Mustela erminea, we show that decisions to switch to alternate prey
was affected by olfactory search costs, and their foraging motivation was
sensitive to the ease with which alternate prey were found. For free living
populations of black rats Rattus rattus we found that prey survival was
significantly enhanced by exposing rats to prey odour cues such that they
ignored formerly conspicuous prey odour cues even when prey was present.
In combination, the results demonstrate that the olfactory conspicuousness
and relative quality significantly influence prey vulnerability, but that
manipulating the background of prey odour cues offers novel opportunities
to protect native species from alien predators.
2011-12-08 14:04 The consequences of interactions between scales of
movement and grains of fragmentation for dispersal success
Cattarino, L.*, University of Queensland; Rhodes, J.R., University
of Queensland; McAlpine, C., University of Queensland;
Understanding the impact of habitat loss and fragmentation on animal
movements is critical for conserving species in fragmented landscapes. We
know that the impact of habitat fragmentation on movements is influenced
by the grain of the fragmentation pattern and the scale of individual
movement. However, how the grain of habitat fragmentation and the
scale of movement interact to affect movement, when the effect of habitat
amount is controlled for, has been largely ignored. We aimed to understand
how the impact of habitat amount, degree of fragmentation and scale of
movement on species dispersal varies with the grain of fragmentation. We
addressed this issue by applying a spatially-explicit simulation approach,
whereby individuals capable of moving at different scales disperse on binary
landscapes, where amount of habitat, degree and grain of fragmentation
vary independently. We show that the effect of the amount of habitat
and the scale of movement on dispersal success depend on the grain of
habitat fragmentation. We also show that the impact of fragmentation
on dispersal success is a function of how different grains of fragmentation
interact together. This has major consequences for how we should manage
species with different life-history characteristics in hierarchically structured
landscapes.
2011-12-07 11:15 Conservation of the prairie dog ecosystem in Mexico
Ceballos, G.*, Universidad Nacional Autonoma de Mexico;
Pacheco, J., Universidad Nacional Autonoma de Mexico; List, R.,
Universidad Nacional Autonoma de Mexico;
Grassland ecosystems worldwide are critically imperiled due to land
conversion, desertification, and the loss of native populations and species.
The Janos region of northwestern Mexico maintains one of the largest
remaining black-tailed prairie dog colony complexes in North America,
supports a high diversity of threatened and endangered species, and provides
environmental services. The rapid deterioration of the Janos grassland
ecosystem has led us to propose a half million hectare biosphere reserve
as the basis to protect the prairie dog grassland ecosystem and the regional
biodiversity, making compatible human economic activities, especially
grazing and agriculture, with conservation. We succeeded in establishing
the Janos Biosphere Reserve by a presidential decree on in 2009. The decree
was the culmination of more than two decades of grassroots scientific
research and conservation work in the. We are now working on a new
paradigm for the Janos region that couples the human dimension and
ecological system. As conservation scientists, this is one of the most critical
challenges of our time.
2011-12-09 15:15 Investigating the decline of the Kaikoura red billed
gulls population: phenotypic and population dynamics perspectives
Celine Teplitsky*, Natural History Museum; Alexandre Robert,
Natural History Museum; John Yarrall, Work and Write; James A.
Mills, Independent researcher; Juha Merilä, University of Helsinki;
Anthropogenic activities are expected to affect phenotypic expression
and population dynamics, but consequences of their interplay is rarely
investigated. The Red billed gull population at Kaikoura (New Zealand)
has been intensively monitored since 1958, birds being individually marked
and followed throughout their lifetime. The population was reduced by >
50% between 1994 and 2003. The average size of the individuals in the
populations has declined over the same period, and a strong female bias in
adult sex-ratio has developed. We investigated whether these concomitant
changes in body size, population size and sex-ratio can be attributed to
the same cause by examining the effects of food availability and climatic
factors on size, sex-specific survival and fecundity rates. Although body
size in Red billed gulls declined over time as a function increasing ambient
temperatures, this decline in body size was not an adaptation to climate
change: we observed no selection for smaller body size or changes in
the genetic composition of the population. On the contrary, reduced
size decreased the probability of breeding, and smaller females also had
lower breeding success. Hence, size decline and associated reduction in
fecundity and population growth rate seems to reflect a response to some
yet unidentified factor that may be anthropogenically induced. Using
projection models, we examine how the observed changes in body size and
fecundity translate to changes in population dynamics.
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