SNT small-grant 2019 for the study of fish diversity in the Sigur River

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The Sigur River

The Sigur River, flowing through the heart of the Nilgiris Biosphere Reserve, provides water to a dry region of significant importance for the conservation of wildlife. The Kamarajsagar dam was constructed across the river in the 1960s. From a perennial river supporting over 30-species of fish, became seasonal and flowed only during the rains. This led to undocumented ecological destruction. There was no fish left in the river after 2000. In 2017 a minimum flow was restored, ensuring the re-establishment of conditions appropriate for ecological restoration.

On the 15th September 2019, the Sigur Nature Trust will provide a small grant (Rs 60,000 maximum) to document the ecological changes. The objectives are to compare the fish diversity of the Sigur River to that of other streams, assess the speed of fish colonization and provide guidelines for long-term management, including food security of local communities.

The grant is exclusively reserved for students. Candidates should send:

  • their biodata
  • a proposal (maximum 3 pages)
  • a budget (1 page)
  • a scan copy of a certificate of registration in an Indian education institution

By accepting the grant, the successful candidate also agrees to share data and provide a report to the Trust in a convenient format chosen by the candidate (M.Sc. thesis or Ph.D. thesis or report or preferably, a scientific publication). The Trust can provide additional support such as data analysis should the candidate request it. The Trust will first disburse half the grant value and the second half will be disbursed after a review conducted at the grantee’s convenience.

The deadline for the submission of proposals is the 1st of September 2019. Applications should be sent in PDF at the e-mail address: sigurnaturetrust@gmail.com.

Tigers in Mysore

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A tiger in Mysore (http://mysorezoo.info/)

 

The following opinion about our paper on tiger gene flow (ref here) was circulated in a Whatsapp group and was therefore, public. Parts of the text were questionable, but I limit my response to technical issues. The text says:

“… If you look at the resistance map closely, you will find that tiger can move through city of Mysore.

…they should have looked at other features…

And it is surprising to see from the data that the forest cover has also improved from open to dense forest…”

The paper should have been read carefully. The legend in figure 2 is clear. There is a decrease in forest cover, not an increase.

Again, regarding “features”, the paper should have been read carefully. We took several variables (the same as other similar recent studies) and simplified to obtain the minimal adequate model. The minimal adequate model is different from other models and this may be due to the tiger genetic make-up, the genetic markers used, the landscape or everything together.

Now, figure 2 does not say that tigers can move through Mysore city. A gene flow resistance map is different from a resistance map extrapolated from movement. Without going into details (found in the paper, which again should have been read carefully), this is how it goes:

We found the same important variables (with correlation coefficients) as in other papers regarding gene flow (terrain, human disturbance, land use, etc), but some, such as land use were not significant. However frustrating it was, land use (vegetation, agriculture, settlements) was discarded. The lack of significance, again, may be due to sampling, markers, etc. But statistics caution that absence of evidence is not evidence of absence.

We were finally left with two significant variables (terrain and human disturbance). The effect of terrain on gene flow was different from that of Central India, but you have to remember that tigers are excellent dispersers and the effect of terrain is in any case, moderate. Then, tigers seem to avoid the “sight” of humans since the human disturbance variable has great effect at low intensity (a non-linear response with a small exponent to the variable).

Now we come to the interesting interpretation: are there tigers in Mysore? No. Except, maybe in the zoo. The figure 2 has its merits however. Viewed from the genetic make up of the genes sampled, and after systematic selection of variables, land use and cities have not been strongly “registered” by the genes. The genetic make up “does not see them”. This is surprising because radiotelemetry would have given entirely different results. But why is that so? Maybe natural selection has not allowed enough time to adjust to land use, since land use changes are recent when natural selection operates on a different time frame. Moreover, how can a species such as the tiger, being systematically killed outside reserves can evolve and adapt to human-dominated habitat? So the landscape seen “through the eyes” of the studied genes is similar to that of the ancestral line of the tiger. The extrapolation of results beyond the study area gives this very strange view of the landscape that only terrain and the sight of humans matter. This is not so outlandish and we do not say that tigers cross or should be reintroduced in Mysore.

This extrapolation was not the purpose of our paper. The paper discussed the difference between Central India and Southern India tiger gene flow in the view of maintaining population connectivity among reserves. The methods used there are solid and every year progress is made in the statistical model selection process. We may have learned something new here. And if it is wrong, it will be discarded by further studies.

Saying gene flow happens differently in different landscapes is rather rational and our paper, commented here by Ruth de Fries (who is an eminent landscape ecology specialist), was not interpreted otherwise.

Jean-Philippe Puyravaud

Call for support – Closed

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Our call for support is now closed, since our generous sponsors – overshot the target. We thank Ms. Naheed Carrimjee, Ms. Priya Nehrurajan, Mr. Raian Irani, Mr. Rémi Daudin and Mr. Rustom Mehta for their generous, invaluable support.

Tiger’s way

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Tiger – Bandipur Tiger Reserve. Photo Rémi Daudin.

We just published the paper “Spatial variation in the response of tiger gene flow to landscape features and limiting factors” in Animal Conservation, available here.

With this paper we were interested in how landscape features affect tiger’s gene flow. What we observed was that the tiger is an amazing animal, not much bothered by obstacles – in rural landscapes or in reserves. But human disturbance, even diffuse, is always a problem. Our paper highlights that tiger preference for dispersal vary depending upon human occupation history. In central India, tigers prefer to disperse along ridges (untouched by agriculture), whereas in southern India, tigers are comfortable in valleys because the main national parks (Bandipur, for example) were set long time ago, on a plain adjoining the Western Ghats.

When I was working on the paper, this difference between central India and southern India bothered me and I could not explain why it should be different. However, a couple of tigers came to mate near the river 200 m from the house. I had THE experts right in front of my nose to confirm that tigers were meeting on flat grounds (the most comfortable for heavy animals to move around). The irreplaceable experience that comes from the field provided the evidence that there was no error in our methods.

As a rule of thumb, tigers can cross human-dominated landscapes as long as no permanent closure (city, highway, etc.) exists. But corridor design and location may depend on regional history, a fact that was unknown earlier.

Jean-Philippe Puyravaud

Global warming will destroy elephants

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Following the 2017 drought, when many elephants died in Tamil Nadu and Karnataka, there was attempts to reassure the public regarding this particular situation (https://www.downtoearth.org.in/news/wildlife-and-biodiversity/elephants-in-drought-hit-karnataka-tamil-nadu-die-to-hunger-thirst-57661).

We posted a blog in this website to warn that if elephant populations were regulated by natural conditions centuries ago, today “unnatural” conditions imposed by humanity, prevail.

Indeed, we have just published an article based on thousands of observations in India and Nepal. With the lead author Dr. Rajapandian Kanagaraj an alumni of the Wildlife Institute of India, and currently at the National Museum of Natural Sciences at Madrid, Spain, this paper shows that global warming will destroy half of the elephant habitat in India. A first modelling technique detected the relationship between environment and elephant range. Then a second set of models proposed range changes under different climate change scenarios.

The results show that by the end of the century, 42% of the present elephant range will be lost because of global warming and land use changes. The temperature increase will affect the vegetation to provoke irreversible ecological damages and make ecosystems unusable by elephants. With impacts of this magnitude, we would also be wise to accelerate adaptation of farming practices because crop and animal production will certainly be badly affected as well.

The view of “business-as-usual” with wildlife – and our world – is an attitude of the past. We enter a period where all efforts possible to protect and mitigate global warming must be made.

Jean-Philippe Puyravaud

Trees comparative ecology

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Plant conservation is driven by local protection and science. We have published a paper in the New Phytologist (soon to be available), on the organization of plant conduits (called xylem). Understanding the anatomy and physiology of plants has plenty of uses, including predicting reaction to global warming and species success in ecological restoration.

Astonishingly, the maximum xylem size (Dmax) of each organ showed similar scaling with plant size and consistent widening from leaf mid-vein via stem to main root across species, independently of growth form, relative growth rate and leaf habit. We also found strong coordination of Dmax with average leaf area and of stem xylem area with whole-plant leaf area. It appears that seedlings of ecologically wide-ranging woody species converge in their allometric scaling of conduit diameters within and across plant organs. These relationships will contribute to modeling of water transport in woody vegetation that accounts for the whole life history from the trees’ regeneration phase to adulthood.

In other words, something as simple as vessel size in plants (measured in standardized conditions), tells a lot about the tree species ecology and allows comparisons among species, that can be used in a variety of applications including conservation action and restoration.

Jean-Philippe Puyravaud

From this year on, children are frightened

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When I came to Pondicherry in 1990, the main vehicle was the cycle. I thought that all efforts should be made to keep it that way. People exercised, the air was clean and the traffic not dangerous, apart from the buses. My reasoning was that city development should be organized to emulate that of Holland, a fairly advanced country at that time, in terms of environment management.

I did not voice my opinion. Firstly, I belonged to a “rich” country and secondly, India was beginning to liberalize its economy and develop economically. All errors that had been committed by others would be imitated. India succeeded superbly, New Delhi being one of the most polluted capitals on earth.

After thirty years in this country, I lived the life of a middle-class Indian and I feel I can now say something, without being accused of neocolonialism: it is time to change the way we use energy.

Greta Thunberg, a 15 year old girl from Sweden, stopped going to school this year, because she knows this:

The less than 2 degrees warming in 2100 of the Paris agreement is 5% likely. We are likely to reach 2 to 4.9 degrees increase with the median of 3.2 degree (Raftery et al. 2017) – with horrendous consequences such as the burning of the Amazonian forest, crops failure and hundreds of millions people migrating. Agriculture in India will suffer.

This will be accompanied with: ocean acidification, water depletion, soil erosion, deforestation and habitat loss.

Xu and Ramanathan (2017) have defined risks categories for climate change. The categories are: more than 1.5 °C is dangerous; more than 3 °C is catastrophic; and more than 5 °C is unknown, implying beyond catastrophic, including existential threats to civilization. Today, we are in the “catastrophic” to the “unknown” categories… about to happen.

These statistics do not talk to us of course. Yesterday we went to work, did our business, sent the children to school and visited our relatives. Tomorrow will be the same. But what predictions say, I am afraid, is that this is about to end in a decade, two decades, half a century? In other words, your children or your grand-children have no future if we continue to use energy the way we do. This is why Greta did not go to school.

It is always possible to act. If not for us, for our children.

Jean-Philippe Puyravaud

Rarity of forest trees

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We have recently published a scientific paper (here) on rare tree species in the Western Ghats of India with colleagues belonging to different institutions.

In general, rarity is of interest to conservation biologists because rare species tend to be at greater risk of extinction than common species. The Western Ghats rain forests have a high proportion of endemic trees (around 64% of evergreen trees ≥10 cm girth at breast height), found only in this biogeographic region. Therefore rare species that are endemic are doubly vulnerable. We estimated that around 48% of 514 species were rare, of which 28 endemics were found in only one site. Rare species had narrower ecological amplitudes, being restricted to particular regions such as the southern Western Ghats and montane forests. Rare species with broader geographical distributions tended to be both wide ranging and locally sparse and narrow ranging and locally dense, and some from single species families could be relictual. Rare species were more likely to be threatened, although 39% have not been evaluated by IUCN. Rarity and endemism increased with increasing family size, indicating that the Western Ghats wet forests are both a cradle of new species (which are rare) and a museum of disappearing species (which are also rare). These forests have been the source of major crops (mango, jackfruit, pepper, cardamon) and should be properly protected because of their unique evolutionary history and biodiversity.

Priya Davidar

Poison in, poison out: bon appétit

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It killed plants, birds, insects, but it’s good for you!

On our trip to France, we decided to drive through the small country roads to reach our destination crisscrossing farmlands, villages and patches of woodlands. We stopped now and then to admire the beautiful villages, churches and agricultural landscapes which seemed deserted compared to India with its over one billion people. Soon I started to notice something odd: everything was too quiet. We did not hear the chirping of the birds, see fluttering butterflies and other insects. We stayed with a friend at Uzès, a small picturesque village in the south with remarkable historical monuments preserved over the ages. The evening descended and the air was filled with chirps of hundreds of birds coming to the avenue trees to roost. These were flocks of starlings. They had left by morning and raucously announced their return at dusk. However, in the countryside, again there were too few birds. Since it was late September I thought that perhaps this was normal, but Jean-Philippe remembered much more life from his childhood.

On return to India, I asked Dr. Raphaël Mathevet, Head of the Department of Ecology at the French Institute of Pondicherry, about the paucity of avifauna in rural France, particularly in agricultural landscapes. He wrote back stating that scientists at CNRS and the Museum of Natural History in Paris had recorded a catastrophic decline in avifauna particularly in agricultural landscapes https://www.lemonde.fr/biodiversite/article/2018/03/20/les-oiseaux-disparaissent-des-campagnes-francaises-a-une-vitesse-vertigineuse_5273420_1652692.html. They have noted an 80-90% decline of some birds since the mid 1990’s that they attributed to agricultural practices such as pesticide and herbicide usage that decreased the number of insects for insectivorous birds, and wild plants for seed eating birds. Agricultural intensification, particularly practices such as spraying pesticides, fertiliser use and weeding was associated with biodiversity loss in European farmlands (https://www.wur.nl/en/show/Effects-of-agricultural-intensification-on-biodiversity-and-ecosystem-processes-on-European-farmland.htm) and destruction of pollination services.

The Europeans may be getting more tolerant of large mammals due to supportive public opinion (http://science.sciencemag.org/content/346/6216/1517.full) but they are killing their small biodiversity. In India, large carnivores survive in human dominated landscapes due to the tolerance of people to wildlife presence. However, with agricultural intensification, we will be following the same way as Western countries. Poison in the environment and in the food. Can it be tolerated?

Priya Davidar

 

Murphy’s law in conservation

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Engineers have the Murphy’s law. Ecologists didn’t have anything similar since evolution through natural selection optimizes ecosystem functioning: if anything goes wrong, it is eliminated. This was before managers came in. At present, in our modern world, we must manage nature. Some problems are addressed and the outcomes are surprising. Here are a few examples:

In certain areas, people are prey for tigers. It is site specific and in the reserves where it happens, not only does the Forest Department try to eliminate or remove the man-eating tigers, the administration also provides a substantial financial compensation to the family. The compensation does not heal people of their pain, but eases some of their difficulties at the worst time possible. Smart guys however, send their old parents to the forest hoping a hungry tiger will find the meal to its taste. And in case no tiger happens to wander into their vicinity, some even take the trouble of doing the tiger’s job. It’s not so simple to be a top predator and sometimes the reward is jail.

The Animal Husbandry Department of Tamil Nadu came to the rescue of the poor with a poverty alleviation program whereby goats were distributed. This should not have happened near protected areas for many reasons, among others: goats destroy vegetation, and herders put their lives in jeopardy getting close to elephants or… tigers. But the destruction was somewhat controlled: the boundless imagination of humans kicked in to resolve the ecological problem and make the poverty alleviation program a success. By stealing the goats, some smart thinkers ultimately help with vegetation regrowth and enrich themselves, till they hit the local TASMAC (the state distributor of alcohol) outlet. The state finally gets its money back and the financial transactions along the way are accounted as development. Everybody wins!

There is a fairly good system for providing rations in the countryside where a lot of people are poor. It avoids tremendous suffering, there is no starvation and it probably contains social problems that may occur if it did not exist. There are minor disadvantages, though: menial jobs can be used to just obtain extra perks from life. Petty criminality (over-harvesting of wood for example), generates extra-money to purchase alcohol. This devastates ecosystems and again, puts people in contact with problematic wildlife. A solution that has not be tried is to ration alcohol. Why not give it a try, after consultation with social-scientists and doctors? Since solutions often create problems, maybe some problems could create some solutions?

Jean-Philippe Puyravaud