Abstracts available here - Society for Conservation Biology

25th International Congress for Conservation Biology • Auckland, New Zealand • 5-9 December 2011
of hogs were ‘pre-conditioned’ under minimum human contact at a ‘prerelease’
facility with simulated natural habitat. Field surveys have revealed
that up to two-thirds of the released hogs survived, and are breeding and
dispersing successfully in the wild. Now, efforts are underway to release 13
similarly ‘pre-conditioned’ hogs in Orang National Park in 2011.
2011-12-07 15:00 Linking Landscape Connectivity, Source-Sink
Dynamics, and Population Viability
Nathan H. Schumaker*, US EPA; Allen Brookes, US EPA; Julie
A. Heinrichs, University of Washington;
The importance of connectivity and source-sink dynamics to conservation
planning is widely appreciated. But the use of these concepts in practical
applications such as the identification of critical habitat has been slowed
because few models are designed to identify demographic sources and sinks,
and popular methods for quantifying landscape connectivity tend to forgo
realism in favor of tractability. Better linkages between connectivity and
source-sink models, and greater biological and ecological realism are needed
before landscape connectivity-based studies can more fully contribute to
conservation planning. Here we illustrate how a new spatially-explicit
population model (HexSim) addresses these challenges. HexSim is a versatile
multi-species, multi-stressor life history simulator that can account for
landscape change, road networks, landscape genetics, disease dynamics, and
many other practical concerns. What distinguishes our new methodology
is that source-sink dynamics and connectivity become emergent properties
of HexSim simulations. It is not necessary to limit biological or ecological
realism, to decompose landscapes into nodes or patches, or to identify
sources, sinks, or dispersal corridors in advance. In this presentation,
we will use a range-wide simulation of the Northern Spotted Owl (Strix
occidentalis caurina) to illustrate the model and methodology, and to tie
our landscape connectivity metrics to the identification of critical habitat.
2011-12-06 10:45 Advance, invading hordes: an experimental island
invasion.
Nathan, HW*, University of Auckland; Clout, MN, University of
Auckland; Murphy, EC, Department of Conservation; MacKay,
JWB, University of Auckland;
The House mouse (Mus musculus) is an important mammalian pest species
both in New Zealand and worldwide. This study follows the invasion of a
small mammal-free island by mice. A founder pair of mice was released
on Te Haupa (Saddle) Island in December 2009. An invasive population
was allowed to establish and persist until August 2010 and was intensively
studied throughout this period. Capture-Mark-Recapture methodology
was used to estimate population size at regular intervals, allowing the
population growth from the initial two individuals to be quantified.
In addition, the hypothesis that mice would be less detectable at lower
population density was tested using selected detection devices and strategies
at regular intervals throughout the study period. Key findings were that
the mouse population showed a logistic pattern of growth characteristic of
many invasive species and that commonly used detection methodologies
were adequate even at low population density. While there have been many
studies investigating the population dynamics of existing populations of
mice, those of a population in the initial stages of invasion have never been
documented. As such this project represents an important advance in the
study of the colonising behaviour of this prolific invader.
2011-12-08 10:42 Influence of Biotic Factors and Spatial Scale on
Range Margin Dynamics Among Competing Species Under Climate
Change
Naujokaitis-Lewis, I*, University of Toronto; Fortin, MJ, University
of Toronto;
Determinants of species’ range limits are a complex interplay between abiotic
factors and biotic interactions that influence persistence. Understanding
the ecological dynamics at species’ range margins is critical for accurately
predicting species’ responses to climate changes and idenitification of
conservation actions. However, our understanding of the relative influence
of processes at the range margins remains unresolved, and likely varies as
a function of scale. Thus it is important to evaluate whether accounting
for biotic interactions improve the fit and predictive power of species
distribution models (SDMs), and whether distribution patterns change with
spatial scale. We developed SDMs for 10 closely related and competing bird
species exhibiting variable patterns of sympatry along the range margins,
and assessed past and future range dynamics under climate change scenarios
using a consensus modelling framework. We applied variance partitioning
approaches to estimate the relative influence of abiotic and biotic variables
and related this to indices of species turnover and co-occurrences across
multiple scales. We show that species ranges margins are temporally and
spatially dynamic in the past, and under future predicted climate changes
but the magnitude of changes were a function of spatial scale. Accounting
for biotic interactions improved model predictive accuracy and was scale
dependent. Our results underscore the need to consider biotic processes
and spatial scale when examining range dynamics and predicting how
species’ ranges will shift with climate change.
2011-12-06 10:45 Applying Shark Attack Policy Responses to
Carnivore Conservation Strategies
Neff, Christopher*, University of Sydney;
Shark attacks illustrate unique problems in carnivore conservation, but they
also offer new insights for the management of endangered predatory species.
With shark bites reported from Boston to Bangkok they represent the
most broad-based human-wildlife conflict in the world. Shark bites garner
public attention in unique ways and negative frames following these events
make the killing of all sharks more publicly acceptable and conservation
more difficult. The beach represents ground-zero in the education of the
public regarding balanced approaches to protecting sharks and protecting
beachgoers. A content analysis of media frames and public policy responses
following shark bites on beaches in South Africa in 2004, Australia in 2000
and the United States in 2001 finds the emergence of a new policy trend
that favors human-control measures in the U.S. and South Africa, even
when sharks are identified as the problem and blamed for the incident. In
these cases, punitive policies were not directed at sharks. These case-studies
offer an applicable analysis for other carnivore conservation efforts, policy
approaches and public education initiatives.
2011-12-07 11:45 Salt marsh as a coastal filter for the oceans: changes
in function with increased nitrogen loading and sea-level rise
NELSON, JOANNA*, University of California, Santa Cruz;
Zavaleta, Erika, University of California, Santa Cruz;
Coastal salt marshes are among Earth’s most productive ecosystems
and provide important ecosystem services, including interception of
watershed-derived nitrogen (N) before it reaches nearshore oceans. N
pollution and climate change are two dominant drivers of global-change,
yet their interacting effects in salt marshes at the land-sea interface are
poorly understood. We examined how sea-level rise and anthropogenic
N additions affect salt marsh N uptake using a dual strategy: a) a fieldbased
manipulative experiment in one marsh over the course of two years;
and b) an observational experiment at nine sites throughout the estuary
in Elkhorn Slough, California. We crossed simulated sea-level change and
ammonium nitrate addition treatments in a fully factorial design. We
found that N-addition had a significant, positive effect on aboveground
biomass (a 315% increase at maximum), plant tissue N concentrations, N
stock sequestered in plants – where marsh plants with added N sequestered
more than four times as much N as controls – and shoot:root ratios. In
the observational study, marsh elevation serves as the simulated sea-level
proxy, and water quality monitoring quantifies the N treatment. Both our
experimental and observational results suggest that coastal salt marsh plants
serve as a robust N trap and coastal filter and that in Elkhorn Slough this
function is not saturated despite high background annual N inputs from
upstream agriculture. However, accelerating sea-level rise, and subsequent
drowning of the marsh, restricts the capacity for buffering the coastal ocean
from eutrophication.
2011-12-08 11:15 Conservation issues in Australian fisheries
management: the application of the precautionary and ecosystem
approaches in five case studies.
Nevill, J*, Retired - University of Tasmania;
The objective of this paper is to examine the ways in which the ecosystem and
precautionary approaches are applied to Australian fisheries management,
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