1 Tahrcountry Musings: February 2011

Monday, February 28, 2011

Amur tigers teetering on the brink?

The latest reports about Amur tigers (Panthera tigris altaica), from a team of scientists from Russia, Spain and Germany, appearing in the latest issue of journal Mammalian Biology is really worrying.
The researchers say the Amur tigers have been reduced to an effective population of fewer than 14 animals. Approximately 500 Amur tigers live in the wild, but the effective population is a measure of the genetic diversity of the Amur tiger.
Genetic bottleneck during the tigers' recent history has been brought out by the research.  Mode shift in allele frequencies tests were positive, while the M-ratio test was negative, indicating the likelihood of a contemporary rather than a historical population bottleneck.   This translates in to a situation where any vulnerability to disease or rare genetic disorders is likely to be passed on to the next generation. A more genetically diverse population of animals has a much better chance of survival. The research highlights the fact that detection of genetic bottleneck signatures in wildlife species is highly relevant for conservation. 

Siberian tiger's recent population bottleneck in the Russian Far East revealed by microsatellite markers
Samer Alasaad, Ramón C. Sorigue, Galina Chelomin,Yury Petrovich Sushitsk and Joerns Fickel
Mammalian Biolog

Importance of Social Science in Conservation

This past weekend, while sipping beer, we discussed the importance of social science in conservation. The starting point of discussion was a paper titled“Conservation and the Social Sciences” authored by,Michael B. Mascia, J. Peter Brosius Tracy, A. Dobson, Bruce C. Forbes, Leah Horowitz,Margaret A. McKean, and Nancy J. Turner

There is often a stark disconnect between our biological knowledge and conservation success. This has led to the awareness among scientists and practitioners that social factors are often the primary determinants of success or failure. Conservation actions are ultimately human behaviors. So it is very germane to understand how social factors work in the scenario. Conservation policies and practices sometimes turn out to be ill-suited to addressing the problems they were intended to solve.

Conservation policies and practices are inherently social phenomena influenced by intended and unintended changes in human behavior. This demands that the social sciences must become an integral part of conservation science and practice.

Social sciences can complement the biological sciences in many ways. For example environmental economics can often provide a powerful rationale for the establishment of protected areas by demonstrating that the value of goods and services generated by pristine ecosystems far exceeds that of a fragmented or transformed landscape.

Anthropological research can document the sociocultural and spiritual value of biodiversity. Together with other social science disciplines, anthropology can also identify the conservation-oriented cultural beliefs, values, norms, and rules which are well suited to serve as the foundation for statutes designed for protected areas.

The authors say “drawing upon the rich literature on the governance of “commons”—forests, fisheries, wildlife and the like—the social sciences can provide valuable insights into how decision-making arrangements, resource use rights, monitoring and enforcement systems, and conflict resolution mechanisms shape individual use of, and thus the state of, protected areas” . “Mainstreaming the social sciences in conservation policy and practice will be difficult, but the stakes are too high and the rewards too great for the conservation community to fail to try.”

There is no doubt that it is the applied tools from both social science and conservation biology that are most needed for successful conservation implementation. It is the need of the hour

Friday, February 25, 2011

Migrants’ role in Conservation and Management

The One-Migrant-per-Generation Rule in Conservation and Management
L. Scott Mills, Fred W. Allendor
Biological conservation

As a man who is in to Nilgiri tahr conservation, habitat fragmentation and connectivity between populations is of great interest to me. The small isolated populations on the Western Ghats are still a source of worry. I found this 2002 paper very interesting and useful against this backdrop.

The optimal level of connectivity between populations has taken centre stage in conservation biology amidst continuing habitat fragmentation and isolation.

The common rule of thumb is that one migrant per generation into a subpopulation is sufficient to minimize the loss of polymorphism and heterozygosity within subpopulations while allowing for divergence in allele frequencies among subpopulations.

In this paper the researchers examine the conceptual and theoretical basis of the rule and consider both genetic and nongenetic factors that influence the desired level of connectivity among subpopulations. They conclude that one migrant per generation is a desirable minimum, but it may be inadequate for many natural populations.

The researchers signs off with the suggestion “a minimum of 1 and a maximum of 10 migrants per generation would be an appropriate general rule of thumb for genetic purposes, bearing in mind that factors other than genetics may further influence the ideal level of connectivity”.
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Have wonderful weekend. The next update will be on Monday or Tuesday

Thursday, February 24, 2011

Flowering Plants and Pollination by Animals

How many flowering plants are pollinated by animals

Jeff Ollerton,Rachael Winfree, Sam Tarrant

Article first published online: 21 FEB 2011


Volume 120, Issue 3, pages 321–326, March 2011

This is a fascinating paper on pollination.

Majority of flowering plants are pollinated by insects and other animals. A minority utilizes abiotic pollen vectors, mainly wind. Plant–pollinator interactions play a significant role in maintaining the functional integrity of most terrestrial ecosystems.

There is no accurate published calculation of the proportion of the ca 352 000 species of angiosperms that interact with pollinators. The estimates vary from 67% to 96% but these are not based on firm data. 
Here an attempt was made by the researchers to estimate the number and proportion of flowering plants that are pollinated by animals using published and unpublished community-level surveys of plant pollination systems.

The researchers say the proportion of animal-pollinated species rises from a mean of 78% in temperate-zone communities to 94% in tropical communities. By correcting for the latitudinal diversity trend in flowering plants, they estimate the global number and proportion of animal pollinated angiosperms as 308 006, which is 87.5% of the estimated species-level diversity of flowering plants. Given current concerns about the decline in pollinators and the possible resulting impacts on both natural communities and agricultural crops, such estimates are vital to both ecologists and policy makers. 

Wednesday, February 23, 2011

More on Wildlife Corridors

The other day I was discussing with my friend Ramesh the pros and cons of corridors. The paper Consequences and Costs of Conservation Corridors was a good starting point for our conversation.

Corridors could alleviate threats from inbreeding depression and demographic stochasticity. Some species require more resources than are available in single refuges. Here a network of refuges connected by corridors may allow persistence. Corridors in riparian forest may constitute an important habitat in its own right.
Now here come the negative impacts. They could transmit contagious diseases. They could be a causative factor for fires, and other catastrophes. They may increase exposure of animals to predation, domestic animals, and poachers. They could prove expensive in economic terms. The researchers say a bridge that would maintain a riparian corridor costs about 13 times as much per lane-mile as would a road that would sever the corridor. Per-unit-area management costs may be larger for corridors than for refuges. Here it may be cheaper to manage some species by moving individuals between refuges rather than by buying and maintaining corridors.
Adequate studies are indeed needed in the field before we recommend the type of corridor.  The researchers say right now a dearth of information on the degree to which different species use corridors makes it difficult to tell which of these potential advantages will be realized in any particular case. Each case must be judged on its own merits because species-environment interactions differ.
Consequences and Costs of Conservation Corridors
Article first published online: 21 APR 2005
DOI: 10.1111/j.1523-1739.1987.tb00010.x

Sometimes back I had posted an item titled “Tools for modeling wildlife corridors” in my other blog Highrangetidings.blogspot.com (I have discontinued this blog). Ramesh feels that this post needs to be posted here as he feels that it would be of use to the wildlife managers. So guys here it comes

The copyright for the entire description belong to corridordesign.org
Here is what is available at corridordesign.org.  They are best suited for designing corridors in a heterogenous landscape at a regional (e.g. 2 - 500 km long) scale.

CorridorDesigner  provides one method of modeling wildlife corridors with ArcGIS.

Here are some other free tools for modeling wildlife or ecological corridors, connectivity, or habitat.
Circuitscape is a stand-alone Python program which borrows algorithms from circuit theory to predict patterns of movement, gene flow, and genetic differentiation among populations in heterogeneous landscapes. It uses raster habitat maps as input, and predicts connectivity and movement patterns between user-defined points on the landscape. Circuitscape is distributed by Brad McRae of the National Center for Ecological Analysis and Synthesis (NCEAS) at University of California, Santa Barbara.
The Connectivity Analysis Toolkit provides conservation planners with newly-developed tools for both linkage mapping and landscape-level 'centrality' analysis. Centrality refers to a group of landscape metrics that rank the importance of sites as gatekeepers for flow across a landscape network. The Toolkit allows users to develop and compare three contrasting centrality metrics based on input data representing habitat suitability or permeability, in order to determine which areas, across the landscape as a whole, would be priorities for conservation measures that might facilitate connectivity and dispersal. The Toolkit also allows application of these approaches to the more common question of mapping the best habitat linkages between a source and a target patch.
FunConn is a functional connectivity modeling toolbox for ArcGIS, distributed by Dave Theobald and the Natural Resource Ecology Laboratory at Colorado State University. The goal of the functional connectivity model is to allow landscape connectivity to be examined from a functional perspective. Functional connectivity recognizes that individuals, species or processes respond functionally (or behaviorally) to the physical structure of the landscape. From this perspective, landscape connectivity is specific to a landscape and species/individual/process under investigation.
Formerly called ArcRstats, the HabMod/ConnMod toolboxes produce multivariate habitat prediction rasters using ArcGIS and the open-source R statistical package for implementing classification and regression (CART), generalized linear models (GLM) and generalized additive models (GAM), and includes a connectivity modeling toolbox. The toolbox is distributed by Pat Halpin and the Marine Geospatial Ecology Laboratory at Duke University
Conefor Sensinode quantifies the importance of habitat areas for the maintenance or improvement of landscape connectivity. It is conceived as a tool for decision-making support in landscape planning and habitat conservation, through the identification and prioritization of critical sites for ecological connectivity.
Path Matrix is a tool for ArcView 3 to compute matrices of effective geographic distances among samples, based on a least-cost path algorithm. It was developed by Nicholas Ray of the Computational and Molecular Population Genetics Lab, University of Bern, Switzerland.
openModeller aims to provide a flexible, user friendly, cross-platform environment where the entire process of conducting a fundamental niche modeling experiment can be carried out. The software includes facilities for reading species occurrence and environmental data, selection of environmental layers on which the model should be based, creating a fundamental niche model and projecting the model into an environmental scenario.
StatMod is an extension for ArcView 3.3 that helps users create logistic regression and CART models using the statistical packages SAS and S-PLUS. It is distributed by Chris Garard of Utah State University.
Maxent provides a maximum-entropy approach for species habitat modeling. The software takes as input a set of layers or environmental variables (such as elevation, precipitation, etc.), as well as a set of georeferenced occurrence locations, and produces a model of the range of the given species. It is distributed by Princeton University.
GRASP (Generalized Regression and Spatial Prediction) is a package for the statistical softwares R and S-PLUS for creating predictive models of species distributions using Generalized Additive Models (GAMs). It is distributed by A. Lehmann, J.R. Leathwick and J.McC. Overton at the Landcare Research Institute, New Zealand.
BioMapper is a stand-alone package for developing ecological niche and habitat suitability models using only a species presence data. It is distributed by Alexandre Hirzel of the Laboratory For Conservation Biology, University of Lausanne, Switzerland.
DesktopGarp is a software package for biodiversity and ecologic research that allows the user to predict and analyze species distributions using presence data. The package is distributed by the University of Kansas Natural History Museum.
Spatial Data Modeler is a collection of geoprocessing tools for adding categorical maps with interval, ordinal, or ratio scale maps to produce a predictive map of where something of interest is likely to occur. The tools include the data-driven methods of Weights of Evidence, Logistic Regression, and two supervised and one unsupervised neural network methods, and a knowledge-driven method Fuzzy Logic.
PatchMorph is an extension for ArcMap which delineates habitat patches from a habitat suitability or land cover map.
Marxan delivers decision support for reserve system design. Marxan finds reasonably efficient solutions to the problem of selecting a system of spatially cohesive sites that meet a suite of biodiversity targets.
PANDA is a stand-alone application developed to provide a user friendly framework for systematic protected areas network design to ArcGIS users. Through the use of P.A.N.D.A. the designer can explore different hypothetical configurations of a system of protected areas in the planning area.
CLUZ is an ArcView GIS interface that allows users to design protected area networks and conservation landscapes. It can be used for on-screen planning and also acts as a link for the MARXAN conservation planning software. It is currently being developed at DICE and is funded by the British Government through their Darwin Initiative for the Survival of Species.
LINK is a set of ArcGIS tools designed to analyze habitat patterns across a landscape. LINK uses species habitat matrices to model potential species habitat and habitat diversity. What sets LINK apart from its predecessors is that it uses raster data sources—raster data sources allow LINK to model habitat over a much larger area than its vector based ancestors.
Jenness Enterprises has created many extensions for ArcView 3.3 useful to ecological applications. Jeff Jenness created the CorridorDesigner ArcMap extension.
Hawth's Analysis Tools is an extension for ArcGIS (specifically ArcMap). It is designed to perform spatial analysis and functions that cannot be conveniently accomplished with out-of-the-box ArcGIS. Most of these analysis tools have been written within the context of ecological applications such as movement analysis, resource selection, predator prey interactions and trophic cascades.

Turtles around the World in Distress

A report issued yesterday which is authored by the Wildlife Conservation Society (WCS) and the Turtle Conservation Coalition, has listed 25 turtle species from around the world as endangered. Seventeen of the 25 species are found in Asia, three are from South America, three from Africa, one from Australia, and one from Central America and Mexico.

Distressingly some of the species likeYangtze giant softshell turtle has less than five individuals. Wildlife Conservation Society veterinarians are working overtime with Chinese officials and other partners to breed the last known male/female pair of these giant turtles, which currently reside at China's Suzhou Zoo.

The report recommends better enforcement of existing trade laws, habitat protection, and captive breeding to preventing turtle species from going extinct while bolstering existing populations.

Monday, February 21, 2011

Re-introductions and the Use of simulation program VORTEX

Assessing re-introductions of the African Wild dog (Lycaon pictus) in the Limpopo Valley Conservancy, South Africa, using the stochastic simulation program VORTEX

Lars A. Bach, Rikke B.F. Pedersen, Matt Hayward, Jesper Stagegaard Volker Loeschcke and Cino Pertoldi

Here is a good paper on reintroduction and use of simulation programme VORTEX. The work was done on African wild dog (Lycaon pictus), in the Limpopo Valley Conservancy, South Africa.

Even though it once ranged throughout Africa, currently the African wild dog only has populations larger than 300 individuals only in three countries (Botswana, Tanzania and South Africa).

In 1998, a plan was launched in South Africa for reintroduction of wild dogs into suitable conservation areas and periodic translocations among them.

The researchers used the stochastic population simulation model VORTEX to evaluate the Limpopo Valley Conservancy in the north of South Africa, as a possible reintroduction site for African wild dogs.
The simulations by the researchers showed that the size of the initial population released only had a small effect on the population dynamics. However, when individuals were supplemented and harvested over a longer period the probability of persistence increased.

Number of females breeding, male mortality, and carrying capacity were key factors in the population dynamics, but simulations by the  VORTEX showed that the severity of natural catastrophes had the greatest influence on the extinction risk and inbreeding.

The researchers suggest that the reintroduction program may be successful, if areas are properly secured, the dogs are held in a boma before release, wild animals or at least a mix of wild and captive animals are used for the release and the animals are vaccinated against rabies.  They reiterate that it is essential to continue monitoring followed by modelling efforts to re-evaluate the success of the reintroduction program.

Sunday, February 20, 2011

Alarming Increase of Phosphorous in World’s freshwaters

Warning bells have been rung by Stephen Carpenter of the University of Wisconsin, US and Elena Bennett from McGill University, Canada about rapid increase of phosphorous in world’s freshwaters.    This excess phosphorous in water causes eutrophication. Eutrophication makes the water non-potable. It also leads to blooms of cyanobacteria that are toxic to humans, livestock and fish.
 The researchers found that current levels exceed all planetary boundaries for phosphorous in freshwater.
The concept of planetary boundaries was first introduced by in 2009 by Rockström et al . They categorized a planetary boundary as a human-determined acceptable level of a key global variable.
The researchers say the current alarming level is despite the fact that in some areas of the world we have a phosphorous shortage.
Dr Carpenter says there are some simple solutions to prevent eutrophication. His prescriptions say "Don't apply phosphorous to soils that don't need it and develop technology for recycling phosphorous.
The authors signs off with following conclusions.
Human release of P to the environment is causing widespread eutrophication of surface freshwaters. Yet the global distribution of P is uneven, and soils of many regions remain P-deficient even as soils of other regions are P-saturated (MacDonald et al 2011). Heterogeneity complicates the task of managing to provide both food and high quality freshwater, surely one of the key challenges of environmental management in the 21st century. The planetary boundary for freshwater eutrophication has been crossed while potential boundaries for ocean anoxic events and depletion of phosphate rock reserves loom in the future. The solution to this problem is widespread adoption of better practices for conserving P in agricultural ecosystems, so that P is cycled effectively among soil, crops, livestock and people without contributing to eutrophication of surface waters. At the same time, P-deficient regions of the world should be supplemented by P from P-rich regions. Such subsidies could come in the form of recycled P in fertilizer (e.g. solid P-rich material from manure digestors) or P in food.

Reconsideration of the planetary boundary for phosphorus
Stephen R Carpenter and Elena M Bennett
Environ. Res. Lett. 6 (January-March 2011) 014009

Saturday, February 19, 2011

Species Introduction in Grassland Restoration

New nature by sowing? The current state of species introduction in grassland restoration, and the road ahead
Petter Hedberg and Wiktor Kotowski

Here is a good paper from Polish researchers on restoration ecology. The paper is authored by Dr Petter Hedberg and Dr Wiktor Kotowski. Both of them are from the Department of Plant Ecology and Environmental Conservation, Institute of Botany, University of Warsaw, Poland

In this paper the researchers reviews the current status of species introduction into semi-natural grasslands, and summarizes the results of published literature in this field.

The review shows that restoration through species introduction is an effective method of establishing dispersal limited species but concludes that we are yet to make use of the fact that Functional Diversity can add to restoration.

 The authors say no single study in their  search has followed up species introduction by measuring any of the currently available indices of functional diversity. According to the researchers this approach is necessary to gain knowledge on what traits are likely to be sorted out in species introduction cases in various environments.

Thursday, February 17, 2011

Flagship Species - providing targeted background information in educational institutions might help strengthen appreciation for less attractive animals.

Attitudes towards potential animal flagship species in nature conservation: A survey among students of different educational institutions
Jürg Schlegel and Reto Rupf

Here is a good paper on how students evaluate the concept of flagship species.  The survey was done in Switzerland. It could be replicated elsewhere for better handling of the concept of Flagship species.

Using a standardized questionnaire, a total of 415 students from two different Swiss primary schools, grammar schools and agricultural schools as well as students from a Swiss University of Applied Sciences were asked about their attitudes towards 27 different indigenous wildlife animal species.
Six mammal, five bird, two reptile, four amphibian and ten insect species, all with potential flagship quality, were presented to the students on a color photograph without any further background information.

The students were asked to give individual reasons for species-related affinity or antipathy. Their ability to correctly identify and name each species was also identified.

Butterflies, birds and most mammals were, on average, more appreciated than reptiles, insects and amphibians. Attitudes also varied according to the type of educational institution attended by the students.

There is no significant difference in attitudes to animals between males and females. Females showed significantly higher affinity for 'loveable animals' and a lesser degree of affinity for 'fear-relevant animals'.
The students exhibited higher affinity for species they can identify than for unfamiliar species.

The authors signs off saying that targeted background information in educational institutions might help soften rigid thinking patterns by strengthening appreciation for less attractive animals.

Wednesday, February 16, 2011

Nature Education and Protected Area Management

The role of education in protected area sustainable governance
Violeta Orlovic-Lovren
Violeta Orlovic-Lovren, (2011) "The role of education in protected area sustainable governance", Management of Environmental Quality: An International Journal, Vol. 22 Iss: 1, pp.48 – 58

Education plays a key role in protected area management. This paper is based on the author’s experience in Serbia but has connotations that have relevance elsewhere. The author says the role assigned to education in promoting sustainability by international documents is yet to be applied to national strategies in many countries.

The focus of this paper is to promote a strategic approach and to identify techniques for analysis to be used in development of quality education programs, tailored to specific needs in protected areas and to sustainability goals in a particular social context.

The author uses an adult education approach and social science methodology to come up with a proposal for a research framework and hopes that this will pave way for better understanding of the role of education in improving sustainable protected area governance.

The existing gap in the field is discussed and a brief review of the issues present in Serbia as a country in transition is also given.

The author concludes that the approach detailed in the paper may be modified to specific contexts and goals, and applied with this purpose to other similar social environments, especially in countries in transition within the region. She is sure that this will lead lead to creating more adequate education programs and increased capacities for managing protected areas.

Tuesday, February 15, 2011

Prey Vulnerability can Influence Habitat Use

Foraging in the Landscape of Fear, the Predator’s Dilemma: Where Should I Hunt?
John W. Laundré, Jesús M. M. Calderas and Lucina Hernández 

Here is a good paper that I read recently. It appeared in the open ecology journal and is very fascinating in its implications. I am giving below the abstract as it is an open journal document.

Under predation risk, prey species are more abundant in areas of low predation risk even at the expense of forage quality. As a result two predictions are possible, 1) predators should choose to hunt in areas with fewer but easier to catch prey than areas where they are more abundant but harder to catch; and 2) the frequency of prey species in the diet of predators using low risk areas should be greater than, or at least equal to, the diet of predators using high risk areas. To test these two predictions, we used data on coyote Canis latrans abundance and diet composition from two habitats in the Chihuahuan Desert of Mexico that have different abundances of jackrabbits (Lepus californicus) and rodents. We used the number of coyote scats found in transects in the two areas to assess coyote abundance and analyzed the contents of these scats to determine diet composition. We found significantly more coyote scats/yr (22.6 ± 4.7 (SE) vs. 12.2 ± 2.4 scats/yr, d.f. = 7, paired t = 3.80, P = 0.007) in the habitat with less jackrabbits and more rodents. However, the percent occurrence of jackrabbits (54.3 ± 6.7% vs. 60.1 ± 7.7%) and rodents (32.6 ± 6.5% vs. 30.1 ± 6.0%) in coyote scats did not differ between the two habitats. These results supported both the above cited predictions and the hypothesis that prey vulnerability can influence habitat use by coyotes.