Peter Leimgruber

Predation on artificial nests in large forest blocks

Neotropical migrant birds are declining within many forest communities in North America and concern exists regarding the impact of forest fragmentation on their breeding success, particularly with respect to nest predation. We studied predation on artificial ground nests in large forest blocks to provide information for comparison with forest fragments and to determine the importance of predator community and vegetation. From May through August 1991, we distributed 320 artificial ground nests over 84-ha study plots and measured 12 vegetational variables at these nests. We used remote-triggered cameras to identify predators. Nest predation rates varied from 5 to 40 % among study plots

Community attitudes toward three protected areas in Upper Myanmar (Burma)

SUMMARY An effective protected area system is essential for thelong-termconservationofMyanmar’sbiodiversity. This study examined the attitudes of 2915 residents in 97 communities around three protected areas (PAs) in upper Myanmar: Alaungdaw Kathapa National Park in the western mountains, Htamanthi Wildlife Sanctuary in the hills bordering the Chindwin and Uru rivers, and Chatthin Wildlife Sanctuary in the central dry zone. Logistic regression indicated a positive attitude toward the PAs was most highly correlated with a perception of conservation benefits and benefits resulting from management of the areas. Attitude was also significantly correlated with a perception of extraction benefits, conflicts with PA staff and crop damage by wildlife. Socioeconomic variables were less powerful than perceptions in predicting attitude and, unlike perceptions, their effectsvariedamongtheareas.Themuchgreatereffect of perceptions, especially positive ones, on people’s attitudes indicates that understanding perceptions is important to improving the relationship between local residents and these PAs. This finding underscores the fact that a focus on conflicts to understand people’s attitudes toward PAs may undervalue or miss critical positive perceptions that people hold. Understanding local residents’ perceptions of PAs makes possible the creation of strategic, place-based management strategies that build on people’s positive perceptions and mitigate their negative perceptions.

Fragmentation of Asia's remaining wildlands: implications for Asian elephant conservation

Habitat loss and fragmentation are main causes for Asian elephant population declines. We mapped wildlands - large, unfragmented and undeveloped areas - asking: (1) Where are the largest wildlands that constitute elephant habitats? (2) What proportion of these wildlands is protected? (3) What is their potential for elephant conservation? Our study demonstrates that wildlands constitute only 51% of the Asian elephant range. Myanmar has the largest wildland (∼170,000 km2), followed by Thailand and India. In Principal Components Analysis (PCA), the first two components explained 73% of the variation in fragmentation among ranges. We identified three fragmentation clusters from the PCA. Cluster A contains large ranges with unfragmented wildlands; cluster B includes ranges with well-developed transportation networks and large human populations; and cluster C contains ranges with severely fragmented wildlands. In cluster A, we identified four ranges with elephant populations >1000 animals: ARYO, MYUC, BNMH and BITE. Together with ranges that support >1000 elephants in cluster B, these A ranges have great potential for long-term elephant conservation. We propose that fragmentation clusters and population size can be used to identify different elephant monitoring and management zones.

Forest cover change patterns in Myanmar (Burma) 1990-2000

Myanmar is one of the most forested countries in mainland South-east Asia. These forests support a large number of important species and endemics and have great value for global efforts in biodiversity conservation. Landsat satellite imagery from the 1990s and 2000s was used to develop a countrywide forest map and estimate deforestation. The country has retained much of its forest cover, but forests have declined by 0.3% annually. Deforestation varied considerably among administrative units, with central and more populated states and divisions showing the highest losses. Ten deforestation hotspots had annual deforestation rates well above the countrywide average. Major reasons for forest losses in these hotspots stemmed from increased agricultural conversion, fuelwood consumption, charcoal production, commercial logging and plantation development. While Myanmar continues to be a stronghold for closed canopy forests, several areas have been experiencing serious deforestation. Most notable are the mangrove forests in the Ayeyarwady delta region and the remaining dry forests at the northern edge of the central dry zone.

BEHAVIOR RATHER THAN DIET MEDIATES SEASONAL DIFFERENCES IN SEED DISPERSAL BY ASIAN ELEPHANTS

Digestive physiology and movement patterns of animal dispersers determine deposition patterns for endozoochorously dispersed seeds. We combined data from feeding trials, germination tests, and GPS telemetry of Asian elephants (Elephas maximus) to (1) describe the spatial scale at which Asian elephants disperse seeds; (2) assess whether seasonal differences in diet composition and ranging behavior translate into differences in seed shadows; and (3) evaluate whether scale and seasonal patterns vary between two ecologically distinct areas: Sri Lankas dry monsoon forests and Myanmars (Burma) mixed-deciduous forests. The combination of seed retention times (mean 39.5 h, maximum 114 h) and elephant displacement rates (average 1988 m in 116 hours) resulted in 50% of seeds dispersed over 1.2 km (mean 1222-2105 m, maximum 5772 m). Shifts in diet composition did not affect gut retention time and germination of ingested seeds. Elephant displacements were slightly longer, with stronger seasonal variation in Myanmar. As a consequence, seed dispersal curves varied seasonally with longer distances during the dry season in Myanmar but not in Sri Lanka. Seasonal and geographic variation in seed dispersal curves was the result of variation in elephant movement patterns, rather than the effect of diet changes on the fate of ingested seeds.

Integrating movement ecology with biodiversity research - exploring new avenues to address spatiotemporal biodiversity dynamics

Movement of organisms is one of the key mechanisms shaping biodiversity, e.g. the distribution of genes, individuals and species in space and time. Recent technological and conceptual advances have improved our ability to assess the causes and consequences of individual movement, and led to the emergence of the new field of ‘movement ecology’. Here, we outline how movement ecology can contribute to the broad field of biodiversity research, i.e. the study of processes and patterns of life among and across different scales, from genes to ecosystems, and we propose a conceptual framework linking these hitherto largely separated fields of research. Our framework builds on the concept of movement ecology for individuals, and demonstrates its importance for linking individual organismal movement with biodiversity. First, organismal movements can provide ‘mobile links’ between habitats or ecosystems, thereby connecting resources, genes, and processes among otherwise separate locations. Understanding these mobile links and their impact on biodiversity will be facilitated by movement ecology, because mobile links can be created by different modes of movement (i.e., foraging, dispersal, migration) that relate to different spatiotemporal scales and have differential effects on biodiversity. Second, organismal movements can also mediate coexistence in communities, through ‘equalizing’ and ‘stabilizing’ mechanisms. This novel integrated framework provides a conceptual starting point for a better understanding of biodiversity dynamics in light of individual movement and space-use behavior across spatiotemporal scales. By illustrating this framework with examples, we argue that the integration of movement ecology and biodiversity research will also enhance our ability to conserve diversity at the genetic, species, and ecosystem levels.

Spatial patterns in relative primary productivity and gazelle migration in the Eastern Steppes of Mongolia

Abstract The Mongolian gazelle ( Procapra gutturosa ) of the Eastern Steppes of Mongolia shows seasonal migrations to traditional winter and calving grounds with diffuse movements during the intervening periods. We used a normalized difference vegetation index (NDVI), derived from coarse-resolution satellite imagery, to map relative primary productivity of steppes between April 1992 and December 1995. Productivity peaks were variable between years, but winter and calving grounds had highest NDVI scores during periods of use by gazelles. Gazelle movements to these areas track shifts in primary productivity across the steppe. Diffuse movements in summer were not matched to peaks in productivity. Productivity ‘hotspots’ utilized by gazelles during critical periods in their life cycle should be first priority for conservation and the impact of livestock grazing on these areas should be evaluated.

From Fine-Scale Foraging to Home Ranges: A Semivariance Approach to Identifying Movement Modes across Spatiotemporal Scales

Understanding animal movement is a key challenge in ecology and conservation biology. Relocation data often represent a complex mixture of different movement behaviors, and reliably decomposing this mix into its component parts is an unresolved problem in movement ecology. Traditional approaches, such as composite random walk models, require that the timescales characterizing the movement are all similar to the usually arbitrary data-sampling rate. Movement behaviors such as long-distance searching and fine-scale foraging, however, are often intermixed but operate on vastly different spatial and temporal scales. An approach that integrates the full sweep of movement behaviors across scales is currently lacking. Here we show how the semivariance function (SVF) of a stochastic movement process can both identify multiple movement modes and solve the sampling rate problem. We express a broad range of continuous-space, continuous-time stochastic movement models in terms of their SVFs, connect them to relocation data via variogram regression, and compare them using standard model selection techniques. We illustrate our approach using Mongolian gazelle relocation data and show that gazelle movement is characterized by ballistic foraging movements on a 6-h timescale, fast diffusive searching with a 10-week timescale, and asymptotic diffusion over longer timescales.

Using relative abundance indices from camera-trapping to test wildlife conservation hypotheses - an example from Khao Yai National Park, Thailand

Khao Yai National Park (KYNP) is well known for its biodiversity and has the potential to serve as a regional model for wildlife conservation. From October 2003 through October 2007, the managers of KYNP conducted a Carnivore Conservation Project to develop and implement long-term monitoring of their large mammal populations. We present these data as an example to demonstrate the usefulness of long-term camera-trapping despite data that cannot be fitted to mark/recapture or occupancy statistical frameworks. Overall, a relatively high number of camera trap photographs was obtained for viverrids (four species; 44 photos) and ursids (two species; 39 photos). However, a relatively low number (range, one to eight) of camera trap photographs was obtained for each of the four felid species and two canid species detected by cameras. Of a total survey effort of 6,260 trap nights, no tigers (Panthera tigris) were detected by camera traps, suggestive of at best a small, non-viable tiger population. Compared to previous camera-trapping efforts at KYNP, we expanded intensive sampling beyond the core area to include all zones and edges of the park. We found significantly lower relative abundance indices (RAIs) for certain mammal species, and collectively for all mammals compared to data obtained in 1999–2000 from 34 similar survey locations, suggesting population declines linked to increased human activity. Information from long-term camera-trapping can provide critical information on the occurrence of elusive species, hotspots, the role of invasive or domestic species, and an indication of the effectiveness of patrolling and other management and conservation interventions.

A mega-herd of more than 200,000 Mongolian gazelles Procapra gutturosa : a consequence of habitat quality

In September 2007 unusual precipitation patterns created conditions in the eastern steppe of Mongolia (drought conditions in many places and wet conditions in one area) that led to the observation of a historically large Mongolian gazelle Procapra gutturosa herd (. 200,000). A model developed to predict gazelle occurrence based on satellite imagery of vegetation productivity correctly identified the region where the mega-herd was located. Additionally, few gazelles were observed in large portions of adjacent, suitable habitat that either had intense insect activity or were undergoing intensive oil development. Because Mongolian gazelles appear to undertake long-distance nomadic movements to cope with a highly variable environment and food availability, development activities that discourage use of limited suitable habitat may ultimately reduce gazelle fecundity or increase mortality. Landscape level conservation strategies that prevent habitat loss and allow access to all of the grasslands seem preferable to strategies that focus on enhancing a handful of protected areas.