Shaily Menon

Climate Change, Biodiversity and Sustainability in the Americas: Impacts and Adaptations

Shaily Menon — Tue, 22 Nov 2011 09:24:50 PST

Book Review of "Natural Climate Variability and Global Warming: A Holocene Perspective" Edited by Richard W. Battarbee and Heather A. Binney

Shaily Menon — Wed, 22 Dec 2010 11:11:28 PST

Recent Advances in the Climate Change Biology Literature: Describing the Whole Elephant

A. Townsend Peterson et al. — Thu, 26 Aug 2010 13:11:58 PDT

Climate change biology is seeing a wave of new contributions, which are reviewed herein. Contributions treat shifts in phenology and distribution, and both document past and forecast future effects. However, many of the current wave of contributions are observational and correlational, and few are experimental in nature, and too often a conceptual framework in which to contextualize the results is lacking. An additional gap is the lack of effective cross-linking among areas of research, for example, connection of sea-level rise and climate change implications for distributions of species, or evolutionary adaptation studies with distributional shift studies. Although numerous important contributions have emerged in recent years, synthesis of this phenomenon and its consequences has not yet been achieved.

Fundamentals for Using Geographic Information Science to Measure the Effectiveness of Land Conservation Projects

Robert G. Pontius Jr. et al. — Thu, 22 Apr 2010 12:44:18 PDT

Some humans spend a tremendous amount of effort to change landscapes from a “natural” state to a “developed” state for a variety of desirable economic uses, such as urban, agriculture, transportation, and mining. Others spend a tremendous amount of effort to prevent such development in order to conserve the landscapes for a variety of important environmental uses, such as biodiversity maintenance, carbon storage, water filtration, and landslide prevention. It would be efficient in theory if a society were to focus its development efforts at locations that give the largest economic utility per area developed, and to focus its conservation efforts at locations that give the largest environmental utility per area conserved. However this is not necessarily the strategy of some important conservation policies. Some policy approaches, such as those proposed by the Clean Development Mechanism of the Kyoto Protocol on climate change and the subsequent Bali Roadmap, call for conservation on land that is under imminent threat of new development, not necessarily on land that gives the largest environmental utility (Sedjo et al. 1998, Clémençon 2008). The apparent motivation to focus policy strategies on land under immediate threat is to prevent development before it exerts its environmental impact. This strategy is nearly a perfect equation for escalation of conflict, because it motivates conservationists to prevent the actions that are highest priority for developers. If conservation is effective in preventing development, then conservationists win and developers lose. If conservation is not effective in preventing development, then developers win and conservationists lose. A third plausible outcome of this policy strategy is that a conservation project might inspire developers to shift their future development from their first priority locations to their second priority locations. The process whereby conservation at one location causes development to shift from that location to another location is known as leakage Leakage can undermine the overall effectiveness of a conservation project in terms of total environmental utility (Schwarze et al. 2002). This chapter presents a general conceptual framework to assess the effectiveness of land conservation projects by using Geographic Information Science (GIS) and land change modeling to analyze development and conservation in the presence of leakage.

Preliminary Global Assessment of Terrestrial Biodiversity Consequences of Sea-level Rise Mediated by Climate Change

Shaily Menon et al. — Wed, 21 Apr 2010 13:07:59 PDT

Considerable attention has focused on the climatic effects of global climate change on biodiversity, but few analyses and no broad assessments have evaluated effects of sea-level rise on biodiversity. Taking advantage of new maps of marine intrusion under scenarios of 1 and 6 m sea-level rise, we calculated areal losses for all terrestrial ecoregions globally, with areal losses for particular ecoregions ranging from nil to complete. Marine intrusion is a global phenomenon, but its effects are most prominent in Southeast Asia and nearby islands, eastern North America, northeastern South America, and western Alaska. Making assumptions regarding faunal responses to reduced distributional areas of species endemic to ecoregions, we estimated likely numbers of extinctions caused by sea-level rise, and found that marine-intrusion-caused extinctions of narrow endemics are likely to be most prominent in northeastern South America, although anticipated extinctions in smaller numbers are scattered worldwide. This assessment serves as a complement to recent estimates of losses owing to changing climatic conditions, considering a dimension of biodiversity consequences of climate change that has not previously been taken into account.

Ecological Niche Modeling and Local Knowledge Predict New Populations of Gymnocladus assamicus a Critically Endangered Tree Species

Shaily Menon et al. — Wed, 21 Apr 2010 12:33:46 PDT

Gymnocladus assamicus is a critically endangered tree species endemic to northeastern India. Local inhabitants traditionally used this species for a variety of purposes. However, rapid population declines led to the species being considered extinct, until fieldwork in 2004 to 2007 identified 14 discrete populations of 1 to 7 trees each. To overcome constraints on field surveys imposed by the region’s remoteness and rugged terrain, we targeted areas of further field inventories by estimating the potential distribution of the species. Ecological niche modeling enabled us to identify 26 sites which the model predicted to be highly suitable for the species’ occurrence. We conducted rapid field surveys at 14 of the most accessible of these predicted sites. New populations were discovered at 5 of the 14 surveyed sites. In the remaining 12 less accessible sites, we interviewed residents from nearby villages and obtained indirect evidence of populations at 5 additional sites, which remain to be confirmed by direct field observations. This study demonstrates the utility of niche modeling as a tool for locating new populations of rare and endangered species. Our results will enhance ongoing efforts towards in situ conservation of this endangered species.

Applications of Geographic Information Systems, Remote-Sensing, and a Landscape Ecology Approach to Biodiversity Conservation in the Western Ghats

Shaily Menon et al. — Fri, 02 Oct 2009 11:51:34 PDT

The mountains along the west coast of peninsular India, the Western Ghats, constitute one of the unique biological regions of the world. Rapidly occurring land-cover and land-use change in the Western Ghats has serious implications for the biodiversity of the region. Both landscape changes as well as the distribution of biodiversity are phenomena with strong spatial correlates. Recent developments in remote-sensing technology and Geographic Information Systems (GIS) allow the use of a landscape ecology and spatial analysis approach to the problem of deforestation and biodiversity conservation in the Western Ghats. Applications of this approach include analyses of land-cover and land-use change; estimation of deforestation rates and rates of forest fragmentation; examination of the spatial correlates of forest loss and the socioeconomic drivers of land-use change; modeling of deforestation; analysis of the consequences of land-cover and land-use change in the form of climate change and change in distribution of biodiversity; biomass estimation; gap analysis of the effectiveness of the protected area network in conserving areas of importance for biodiversity conservation; and conservation planning. We present examples from our work in the Western Ghats, in general, and in the Agastyamalai region and Biligiri Rangan Hills, in particular, as well as that of other researchers in India on various aspects of applications of GIS, remote-sensing, and a landscape ecology approach to biodiversity conservation.

Deforestation in the Tropics: Reconciling Disparities in Estimates for India

Shaily Menon et al. — Wed, 02 Sep 2009 12:08:54 PDT

Here we examine recent disparate estimates of deforestation obtained for India. We discuss the sources of disparity and the implications of inaccurate estimates and suggest ways in which future attempts at estimating deforestation might reconcile the disparity. Despite the importance of deforestation and its consequences, no attempt has been made to reconcile the different estimates obtained for India.

Identifying Conservation-Priority Areas in the Tropics: A Land-Use Change Modeling Approach

Shaily Menon et al. — Wed, 02 Sep 2009 12:08:53 PDT

Most quantitative methods for identifying conservation-priority areas require more detailed knowledge about the extent and distribution of biodiversity than is currently available. Accelerated and irreversible losses of biodiversity call for the development of alternative methods to identify priority sites for biodiversity inventory and protection. We focused on the state of Arunachal Pradesh, a biodiversity-rich region in northeast India. We used a geographic information system and spatially explicit modeling to examine the correlation of land-cover and land-use patterns with biogeophysical characteristics and to project future patterns of land-use change. In 1988, 70% of Arunachal Pradesh was covered by forest. We project that 50% of the state's 1988 forest will be lost by 2021, based on anticipated growth of the human population and resulting resource use. Of the total simulated deforestation, 76% occurs in areas that have no legal state protection. We developed a map of threats to biodiversity that divides areas that were forested in 1988 into four categories: (1) susceptible to future deforestation and currently unprotected; (2) susceptible to future deforestation but currently within the protected-area network; (3) not susceptible to future deforestation and protected; and (4) neither susceptible to future deforestation nor currently protected. We make the following recommendations based on our analyses. Areas in category 1 should be a high priority for biodiversity inventory and conservation action. Areas in category 2 should have rigid enforcement of protection. Areas in category 3 are locations of relatively low priority for enforcement. Areas in category 4 that have a high conservation potential are politically the easiest to include in the protected-area network and should be protected before they become targets of future land-use change. Reserve forests-forests managed by the state forest department for a variety of purposes, including selective logging for timber harvesting-are predominantly located in areas susceptible to land-use change and are prime candidates for upgrading of protection status.

Projected Climate Change Effects on Nuthatch Distribution and Diversity Across Asia

Shaily Menon et al. — Wed, 02 Sep 2009 12:08:52 PDT

We used ecological niche modeling approaches to explore climate change implications for one family of birds, the Sittidae, in Asia. Quantitative niche models based on present-day distributions for each of 13 species were projected onto future climate change scenarios. Species’ potential distributional areas tended to be predicted to retract along their fringes, and at lower elevations along mountain ranges. As observed in other studies, montane systems were relatively more robust to the horizontal effects of climate change on species’ distributions compared to flatland systems, so range contractions were focused in Southeast Asia and peninsular India.

A Vegetation Based Approach to Biodiversity Gap Analysis in the Agastyamalai Region, Western Ghats, India

B. R. Ramesh et al. — Wed, 02 Sep 2009 09:53:16 PDT

Protected areas in India have historically been established on an ad hoc basis with little attention to the conservation value of an area. This study focuses on a set of protected areas in the Agastyamalai region of the Western Ghats (WG), India. We examine forest loss and land-use changes in the study area from the early 1900s to 1960 and from 1960 to 1990. We use GIS to perform a biodiversity gap analysis of the protected areas in the study site. We produce a detailed map of existing floristic types and use it to generate layers corresponding to floristic species richness, zones of floristic endemism, floristically unique areas, and habitat distribution of representative endemic faunal species. These layers are combined with a map of the protected area network to highlight areas of high conservation value excluded from adequate protection. Deforestation rates are high in the study region and several areas of high biodiversity value are excluded from the highest levels of protection. We offer this method as a step toward developing a utilitarian conservation value index for assigning conservation and management priorities.

Biodiversity Monitoring: The Missing Ingredient

Kamaljit S. Bawa et al. — Wed, 02 Sep 2009 09:47:17 PDT

With mounting losses in biological diversity, inventorying and monitoring of biodiversity to assess the magnitude and rate of losses are emerging as dominant themes in conservation biology. Inventorying has been defined as the surveying, sorting, cataloging, quantifying and mapping of entities ranging from genes to landscapes¹ and monitoring has been defined as the surveillance of the compliance with or deviation from a predetermined standard². Renner and Ricklefs³ argued that rushed inventories will compromise scientific rigor and have little influence on decision making. More recently, Stork et al.⁴ argued that losses in biological diversity are so severe that inventorying and monitoring must be accorded a high priority and can have a major impact on policy-making and public opinion.

Effectiveness of the Protected Area Network in Biodiversity Conservation: A Case-study of Meghalaya State

M. Latif Khan et al. — Wed, 02 Sep 2009 09:38:53 PDT

The North-Eastern region of India is significant for biodiversity conservation because of its floristic richness and high levels of endemism. Deforestation levels are high in the region due to anthropogenic pressures. We accessed various literature sources to create a database for Meghalaya state containing information on plant species, habit, altitudinal distribution, endemism, and endangered status. Information on the existing protected area network (type, extent, and altitudinal representation) was added to the database. The database was used to assess the effectiveness of the existing protected area network in conserving the floristic biodiversity of the state. Of a total of 3331 plant species, 1236 (37.11%) are endemic of Meghalaya and 133 (4%) are confined to 'sacred forests'. However, 'sacred forests' are not legally protected areas. Only 32,220 ha (1.43% of the state's geographical area) is protected under the category of National Park or Sanctuary. Although 212 species (17.15% of the state's endemic species) occur only in Meghalaya at altitudes above 1500 m, none of the forests at these altitudes are protected as National Parks or Sanctuaries. We conclude that the existing protected area network does not effectively conserve the state's unique biodiversity and suggest measures by which its effectiveness might be increased.

"The original publication is available at www.springerlink.com."

Lion-tailed Macaques (Macaca silenus) in a Disturbed Forest Fragment: Activity Patterns and Time Budget

Shaily Menon et al. — Wed, 02 Sep 2009 09:31:19 PDT

We describe the activity patterns and time budget of a feral group of lion-tailed macaques that were confined to a disturbed forest fragment of 65 ha and compare the results with those obtained for groups in protected forests. The degraded nature of the study site was reflected in low tree densities, low specific diversity, gaps in the girth distribution of trees, and frequent disturbance by humans. The study group of 43 subjects was twice as large as lion-tailed macaque groups in protected habitats. They spent the most time ranging (34.0%), followed by foraging (23.7%), feeding (17.9%), resting (16.0%), and other activities such as social interactions (8.4%). Monthly variations are significant for all activity categories except ranging. Times spent resting and foraging are negatively correlated (r=-0.5) and show significant seasonal differences. Foraging time was highest from September to November, when key food sources such as Cullenia and Artopcarpus were absent or marginally available. The study group spent most time (40.4%) at canopy levels between 21 and 30 m. They spent more time each day ranging than resting or feeding and more time terrestrially compared with groups in protected forests. Large group size, poor habitat quality, and seasonal variation in food availability were the major variables affecting their time budget, and these variables accounted for differences from the time budgets of groups in protected forests. "The original publication is available at www.springerlink.com."

Cloning and Conservation of Biological Diversity: Paradox, Panacea, or Pandora's Box?

Shaily Menon et al. — Wed, 02 Sep 2009 09:16:41 PDT

The success of a Scottish team in cloning a mammal from an adult tissue cell has generated considerable speculation in the popular press about potential applications to conservation biology. Possibilities that have been mentioned include cloning endangered species and creating gene banks for the germplasm of rare species. Sensational or inaccurate reports might encourage the mistaken notion that cloning technology is more advanced or reliable than it actually is. More important, such reports might foster the myth that there is no longer an urgency to conserve endangered species or their habitats as long as we have frozen germplasm and cloning techniques. It is our responsibility as conservation biologists to examine the promise as well as the limitations of cloning technology, to dispel myths related to the application of cloning technology to biodiversity conservation, and to reflect once again on the paradigms and approaches of conservation biology.

"The definitive version is available at www.blackwell-synergy.com."

Preliminary Analysis of the Ecology and Geography of the Asian Nuthatches (Aves: Sittidae)

Shaily Menon et al. — Mon, 17 Aug 2009 11:29:06 PDT

We explored distributions of Asian nuthatch species in ecological and geographic space using ecological niche modeling based on occurrence data associated with specimens and observations. Nuthatches represent a well-defined clade occurring throughout the Northern Hemisphere, but are most diverse in southern Asia where 15 of the 24 species occur and where the lineage is believed to have evolved. Species richness was focused in a narrow east-west band corresponding to the forested parts of the Himalayas with a maximum number of nine species predicted present in these foci. The distributional predictions have a mid-elevation focus with highest species diversity between 1,000 and 2,000 m. Niche breadth and volume were positively related, but accumulation of distributional area (niche volume) decreased with additional environmental combinations (niche breadth). The extent of potential range filling, a measure of distributional disequilibrium, was connected with montane habit ([R²] = 0.422) indicating that montane situations limit the distributional potential of species.