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Western Ghats’ fish fauna in peril: are pseudo conservationist attitudes to be blamed?
Get PDFUse of threatened species in research – be it for taxonomy, biology or population studies, has always invoked much debate. As a result, the Species Survival Commission of the International Union for Conservation of Nature (IUCN)
developed a set of guidelines entitled ‘IUCN Policy Statement on Research Involving Species at Risk of Extinction’ with special reference to scientific collecting
of threatened species1
Isolation and characterization of polymorphic microsatellite loci from the invasive plant Lantana camara L.
No full textLantana camara is a highly invasive plant that has established itself in at least 60 different countries
across the world. Here, we report development of ten
microsatellite markers for this species. These microsatellite loci have 2–15 alleles per locus; with observed and expected heterozygosity of 0.022–0.833 and 0.336–0.848, respectively. These markers will be useful in addressing a variety of questions about Lantana camara, including those concerning breeding system, pollination and dispersal, genetic variation and population structure
Patterns and processes of Lantana camara persistence in South Indian tropical dry forests
Get PDFInvasive species have been recognized to be an important threat to biodiversity and ecosystem
functioning. I examined the patterns of Lantana camara (hereafter, lantana) invasion and the
effects of lantana invasion on native plant communities in a tropical dry forest in the Biligiri
Rangaswamy Temple Wildlife Sanctuary (hereafter, BRT), Western Ghats, India. I then
examined how patterns of lantana spread are related to factors such as disturbance (e.g., forest
fires and historical habitat modification) and habitat structure. In order to link pattern with
process, I investigated the role played by soil seed banks as a potential mechanism underlying
lantana success in BRT. Lastly, I examined how local people perceive lantana invasions. I tabled
results from both traditional ecological knowledge sources and scientific sources about the
patterns and processes of lantana invasion and drew out implications for the future management
of lantana-invaded landscapes.
Data on the distribution of lantana and native species in 1997 came from an existing study. In
1997, the entire 540 km2 study area was overlaid with a 2-km grid to yield 134 cells, and an 80 m
x 5 m plot was established in the centre of each grid cell. I re-visited the same set of plots in
2008 to arrive at the change in the density and distribution of lantana and native species.
Additionally, I explored the effects of lantana density on the native woody species community,
particularly diversity, abundance, evenness, size class distribution, and relative dominance. Over
11 years there was a tremendous increase in lantana abundance and density. Lantana was present
in only 41% of plots inventoried in 1997, but by 2008 lantana had spread to 81 % of all plots.
Lantana invasion was accompanied by a reduction in native species density and diversity.
Lantana invasion was also accompanied by a reduction in evenness in the native community. In
addition there was evidence for drastic reductions in the regenerating size classes of trees,
suggesting that tree population declines may occur in the future. Lantana was found to be the
most dominant species in BRT.
The BRT landscape has experienced and is experiencing a variety of disturbances. Historical
disturbance factors, such as selective- and clear-felling of trees, extraction of bamboo and grass resources, and slash-and-burn agriculture, could have created conditions favorable for lantana
invasion. Contemporary disturbance factors, such as roads, and human-caused disturbance (e.g.,
collection of non-timber forest products or fuel-wood) may also play a role in driving lantana
invasions. Lantana invasion could also be driven by an increase in fire frequency, since lantana
resprouts in response to fire. Propagule pressure from sites already invaded by lantana could
further enhance lantana invasion. Finally, lantana invasion would be influenced by the
availability of suitable habitat. I modeled the rapid spread of lantana using explanatory variables
such as historical habitat modification, current human disturbance, fire frequency, propagule
pressure, and habitat suitability. Using an information-theoretic, model-selection approach, I
focused the modeling exercise on the three distinct stages of biological invasion — arrival,
establishment, and spread. Lantana arrival was best explained by propagule pressure, rather than
disturbance factors or habitat suitability. Lantana establishment on the other hand, was limited by
fire frequency. Lastly, I found that lantana spread was influenced largely by proximity to
historical disturbance, such as old plantations.
Management efforts aimed at controlling the invasion of lantana and of other potentially
problematic invasives are limited by the lack of information on the mechanisms that may
enhance their success. The ecology of soil seed banks is one such mechanism. I explore the role
played by soil seed banks in enhancing the success of two common invasives in BRT — lantana
and Chromolaena odorata (hereafter, Chromolaena). Results from this study indicate that the
soil seed bank is saturated with seeds of lantana and Chromolaena vis-à-vis native species.
Lantana forms persistent seed banks, implying that for any kind of control, lantana seed output
first has to be reduced. Reducing seed output could be achieved by reducing the density of adult
lantana plants. Furthermore, repeated removals would have to be continued till lantana seed
banks in soil are depleted. However, results from this study also indicate that lantana seed banks
are negatively affected by fire. Repeated removals, combined with fire could be explored as a
method to control lantana regeneration. Chromolaena, on the other hand, does not seem to be as
pervasive as lantana.
Lastly, I explored how resident communities view lantana invasions. An indigenous community,
the Soliga, have been residing in BRT for centuries. I used an open-ended interview schedule to solicit Soliga thoughts on lantana invasion in BRT. The Soliga cited three main reasons for
lantana spread: its copious fruit output and wide dispersal, the decrease in fire frequency, and the
historical extraction of grass and bamboo resources. According to Soliga views, the nature of the
lantana-fire relationship depended on lantana abundance. At a low lantana density, the
occurrence of early dry-season fires was seen as a way to control lantana from spreading. At a
high lantana density, the occurrence of forest fires was seen as beneficial for lantana, since fires
were more intense and negatively affected native species due to the additional fuel provided by
lantana biomass. The hampering of natural regeneration of native species due to the thick growth
of lantana, which, in turn, curtailed native species seedlings from accessing light was also cited
as a further contribution to lantana success. The Soliga believed that lantana invasion has had a
negative effect on forest composition and structure, and on their livelihoods.
Tabling scientific knowledge with traditional ecological knowledge has led to an improvement in
our understanding of lantana invasions in BRT. Some aspects of lantana invasion, such as the
role of propagule pressure and response of native tree communities were corroborated by both
traditional and scientific sources. However, some aspects, such as the role of fire in lantana
invasion were surprisingly contradictory. According to the Soliga, at low lantana densities fire
may play a role in limiting lantana, a view contrary to scientific studies that hypothesize a
positive relationship between lantana and fire. However, both traditional and scientific
knowledge sources agree that fires in high lantana density areas, if they occur, could be
destructive for native species. The patterns of lantana spread indicate the serious threat posed by
lantana to native plant biodiversity and the structure of this tropical dry forest landscape.
Although fire frequency was observed to limit lantana establishment, and also appeared to reduce
the density of viable lantana seeds stored in soil, a precautionary approach should be adopted
before utilizing fire as a management tool to control or eradicate lantana. Since fires are likely to
burn more intensely due to the build-up of lantana biomass, reducing biomass via lantana
removal may be required before fires could be used to control lantana
Tree diversity, distribution, history and change in urban parks: studies in Bangalore, India
No full textUrban parks constitute critical biodiversity hotspots in crowded, concretedominated
city environments. Despite the importance, they remain little researched. This
paper assesses the biodiversity and distribution of trees in urban parks in the southern
Indian city of Bangalore. 127 plots were used to survey tree distribution in parks across the
city. The distribution is largely dominated by a few common species. The proportion of
exotic species was very high, with 77% of trees belonging to introduced species. Park
history had an impact on distribution. Old parks had fewer but larger trees, and greater
species diversity compared to recently established parks. Old parks also differed in species
composition, having a greater proportion of large canopy trees compared to young parks.
Examination of size distributions revealed that large canopied species were gradually being
phased out, and replaced by narrow and medium sized tree species which are easier to
maintain, but which may not provide the same environmental and ecological benefits.
Greater attention requires to be paid to the selection of trees in cities, not just with a view to
easy maintenance as is currently the case, but to select an appropriate mix of trees that
supports biodiversity and maximizes environmental and ecosystem services
Misreading the Issues and the Landscape
No full textThe question of how to govern India’s forests is an enormously complex one, given the inherent socio ecological diversity of the subcontinent and the procrastination and ad hoc approach of independent India to the problems generated by colonial forestry. The
Forest Rights Act 2006 (FRA) is the first legislation to address some of these i ssues. Differences of opinion regarding the clarity and feasibility of specifi c elements in the FRA will no doubt exist, and a discussion
of the report of the Ministry of Environment and Forests and the Ministry of Tribal A ffairs (MOEF-MOTA) Joint Committee on the FRA (FRAC) that was submitted in January 2011 is welcome. But the debate can do without the egregious misreading of the FRA and FRAC report that is apparent in the comment by Bhargav and Dattatri (23
April 2011; B&D hereinafter). As members of the FRAC who contributed substantially to its report, we feel compel led to respond to this piece of non-analysis
Sourcing local solutions for conflict
Get PDFAltering or clearing forests for farming and other activities leads to fragmentation of wildlife habitat, which
in turn results in a cascade of negative impacts. For instance, farmlands near or across an animal’s migratory route can lead to crop damage and losses to both humans and wildlife, a situation commonly known as human-wildlife
conflict. The Mysore-Nilgiri corridor in southern India is both a traditional route for wildlife such as elephants
and a resource base for local people, and holds considerable conservation value. While studies have investigated direct and hidden costs of conflict, we still need site-specific understanding of the issue to provide solutions. In this landscape as in others, most proposed
conservation plans and forestry policy decisions tend to ignore the livelihood resources of forest dependents
Lantana camara invasion in a heterogeneous landscape: patterns of spread and correlation with changes in native vegetation
No full textThe effects of invasive species on community structure remain under-investigated due to the lack of long-term data. Our objectives were to examine the correlation between Lantana camara L. invasion and native species abundance, distribution, diversity, and population structure, across different forest types in a heterogeneous landscape. We examined changes in native vegetation and L. camara between 1997 and 2008. We used existing vegetation data from 134 plots spread across the 540 km2 landscape from 1997 and re-censused these plots in 2008. We then examined the change in species richness, Shannon’s diversity, evenness, and population structure of native species from 1997 to 2008. We also examined the relationship between L. camara density and species richness, diversity, evenness, and population structure. The presence and abundance of L. camara increased dramatically from 1997 to 2008. L. camara occurred in 81% of plots by 2008, compared with only 41% of plots in 1997. Similarly, the mean density of L. camara increased almost fourfold from 1997 to 2008. This was accompanied by a change in native community structure. Species richness, diversity and evenness declined significantly in some forest types, and at the landscape scale. There were also changes in the population structure of native tree species, with reductions in the density of tree saplings, possibly due to competition with L. camara. We demonstrate the pervasive threat posed by L. camara to native vegetation at the scale of individual forest types, and at the larger landscape scale, in our study area. These changes have long-term consequences for forest structure and composition
Litsea kakkachensis (Lauraceae) – A new species from Agasthyamalai, Western Ghats, India
No full textLitsea kakkachensis R. Ganesan, a new species of Lauraceae from Agasthyamalai hills, southern Western Ghats is described with illustration. It differs from its allied species L. venulosa (Meisn.) Hook.f. in number of lateral
nerves, fl oral characters and shape of the fruit. The habitat, phenology, abundance and threat status are also
discussed
Rereading the interdisciplinary mindscape: a response to Redford
No full textKent Redford (2011) offers a reading of the social science discourse on conservation to make a call for greater and better collaboration between social scientists and conservationists. As someone whose initial training as an engineer socialized him into being dismissive about the social sciences, who then struggled to understand and integrate a social science perspective into his work, and who has campaigned for greater interdisciplinarity in environmental research, I find Redford’s description of the evolution of his
own thinking refreshingly frank and his call for greater
openness and collaboration very encouraging. But fostering greater understanding and collaboration across these boundaries may require greater clarity about the categories, roles and values of the disciplines and people involved. Redford characterizes the problem as one of social scientists being too indifferent towards, or too critical of, conservationists, and argues that some of the criticism is based on misreading the conservation(ist) landscape. I suggest that a better understanding of the indifference and criticisms is provided by a clearer separation of the roles of academics versus activists and a fuller appreciation of the different normative stances across social and conservation activists
Biodiversity access and benefit-sharing: weaving a rope of sand
Get PDFThe Convention on Biological Diversity (CBD)1 is one of the most important treaties in the history of humanity as it deals with the infinitely complex but fragile diversity of life on earth. Regulating access to genetic resources and equitable sharing of commercial benefits of biodiversity has been the most contentious issue in the negotiations under CBD. As the impasse continues, the prime objective of CBD – conservation of biodiversity
– is relegated to the backyard. The Nagoya Protocol (2010)2 adopted by the Tenth Conference of Parties (CoP), concluded on 29 October 2010 in Nagoya, Japan, provides the framework to facilitate access and benefit-sharing (ABS). However, the idea of ABS itself remains
a pipe dream