Whenever I read about successful conservation efforts I'm reminded of the Northern Hairy Nose Wombat.
There are very few of these animals left - just 163 at the last census. One year a single dingo breached a fence and killed 10% of the population.
They all used to be in a single location, but a second location has been set up and some animals seem okay there. Populations are gradually increasing. The numbers dropped to about 90 animals, and that seems like a severe bottle-neck. I'm curious whether that'll contribute to genetic flaws in later populations.
A lot of animals have had severe bottlenecks like that in the past. Cheetahs, for example, have so very little genetic diversity that they're all essentially cousins; cheetahs will accept skin grafts from any other cheetah with no fear of rejection. Humans have also had a pretty extreme bottleneck in our history, with estimates that there were no more than about a thousand alive at one point, which is why we don't have the diversity many other animals have. If we manage the remaining population carefully, even a small population can rebound with few fears of later genetic problems.
Nitpick: a historical population bottleneck does not necessarily mean that only that many individuals were left alive at a single time; it only means that that many individuals from a single time successfully contributed to today's population.
Simple example: imagine you have two groups of humans, A and B, living in two neighboring valleys. Group A consists of 1000 individuals, group B a million. Over the next several hundred or thousand years, group A thrives and slowly increases to a million people. Meanwhile, group B declines to extinction at an even pace.
At no time were there fewer than a million people, but there was a population bottleneck of 1000 people.
In that scenario you could make a pretty good argument that group B were not modern humans but instead a dead race. (Assuming they had all these unique genes that disappeared.)
I'm not sure the nitpick makes things more accurate.
"Race" is not really a recognized concept outside of social interaction. I believe "sub-species" is preferred on the level that you're indicating—think neanderthals and denisovans. Even then, it's a measure of phylogenetic distance, not of any quality that directly "matters" (like fertility of offspring).
Anyway, they're all humans in terms of having active sex with humans.
I don't understand where you're going with this in relation to saalweachter's imaginary groups A and B. Neanderthal genes have nothing to do with population bottlenecks.
If you want to get more complex, you could assume that group A was a colony from group B and that they were a genetic subset of group B.
It's also possible that group A and group B were still economically linked, with frequent trade between the two but no intermarriage.
It's also possible that group A and group B were never at any time distinct groups, and the individuals who 'won' genetically were scattered through time and space among a larger population. Imagine a rare mutation that confers an immunity to a terrible disease which periodically ravages the population. It's not that the plague kills off all but 1000 people, it's that over centuries of large numbers of people being killed off, those descending from the few people with the mutation (and their mates) come to dominate the gene pool, even if there were always millions of survivors.
The reason for the nitpick is that the idea of a human population bottleneck is almost-always interpreted as "humans almost went extinct!". Maybe that happens to be the case, but it isn't necessarily so.
In that scenario, with lots of gene mixing going on, there isn't really a cutback of genes at any point. There is only a requirement that those thousand people are somewhere in everyone's ancestry. This is very different from them being the only ancestry. The useful gene spreads throughout the population with no bottleneck. No genetic variety goes away except in the case that it's specifically incompatible with the anti-plague gene.
Even without die-offs, you approach a situation where everyone shares all (millions) of their ancestors at some depth. Having a particular thousand somewhere in a logistically-growing list is not the same as domination.
Tigers are spread through out India from North to South. About 50% of world's tiger population is in India (based on numbers in 90s) so a 30% increase in the population in India bodes very well for the over all tiger population.
The Tasmanian devil population is expected to crash over the next five years as well. However researchers are not worried about lack of diversity because I think they are already all seriously inbred. The strategy against devil facial tumour is to let the wild population die out and reintroduce from breeding programs established on Islands and the Tasman peninsular.
Though there is an increase in certain pockets, there is no attitude change in the Indian government towards forest/wildlife conservation in aggregate (at all!), as evident by the deforestation activities on the outskirt of Sundarban.In fact as we speak two important areas are being bulldozed:
This little increase in the population of tigers is almost just a facade for the actual mentality of Indian Government (Bureaucracy in particular) towards Environment which is often viewed as "Just a formality"
Great news unless you are living in a village near the tigers. These are not animals I would want living near me. There are an estimated 270 tigers in Sunderbans National Park. They kill 100-250 people a year.
I have watched a few documentaries on this topic. I know it sends you spine chills even thinking about it, but many of the attacks are because the men go and gather honey and fish in the Tiger territory because they have almost exhausted them on their side.
I wonder many a times, we simply cannot co-exist to create an ecological balance with anything.
To quote Agent Smith in the movie Matrix:
"It came to me when I tried to classify your species and I realized that you're not actually mammals. Every mammal on this planet instinctively develops a natural equilibrium with the surrounding environment but you humans do not. You move to an area and you multiply and multiply until every natural resource is consumed and the only way you can survive is to spread to another area. There is another organism on this planet that follows the same pattern. Do you know what it is? A virus. Human beings are a disease, a cancer of this planet."
> Great news unless you are living in a village near the tigers.
This fear that people have of nearby predators is, in fact, a real problem with conservation efforts to preserve those predators. David Quammen addresses this aspect of conservation in his book "Monster of God". He believes the fear of predators is more deep-seated in our psyche than most other fears.
I suspect your 100-250 number is high (perhaps way high?) but it only takes one in a village where everyone knows everyone to ratchet-up fear. If a neighbor kid were taken by a bear, I'd sure want the authorities to do something about that bear.
Just trying to figure out the circumstances where a bear could "take a child" that don't involve some serious negligence on whoever is supposed to be responsible for the kid. I grew up in a part of the US that is rife with bears and spent my childhood running around in wild areas with coyotes and rattlesnakes and never had any sorts of issues.
That's an unpopular opinion of course, but it's important to understand the attitude of the people living around them. The Outside Online article linked by avemuri elsewhere in this thread gets into the issue. Wildlife conservation is important, but I can't help but empathize with the people living in the surrounding area. With very little work and very little money to go around, and with tigers killing their livestock and rhinos getting into their crops, what are they supposed to do? It doesn't even have to happen often for it to become quite a contentious issue.
A simple way is to just pay the farmers for the damage.
For example, the group Defenders of Wildlife was faced with a similar situation in Montana, where the wolves were getting shot because they ate the livestock of the area. They raised money and paid for the losses in exchange of the promise that the ranchers wouldn't kill the wolves.
This doesn't help if people are attacked, of course.
Wolf damage to sheep herds in France is also paid for. There is still opposition to the wolf presence but I guess not being threatened with bankruptcy helps smooth some edges.
Also wolves help control the wild boar population, and those can be quite damaging for crops, so the economic impact of the wolf may actually be positive.
Eventually, someone is bound to be attacked thought, it will be interesting to see how policy is influenced when it happens. I can see how tigers can be a lot more polarizing.
That would probably work well, but only if the park has money. In the Outside Online article, a group of poachers were convinced to stop with the promise that they wouldn't be prosecuted and that they would get help to support themselves, but they are struggling to make good on that promise because they just don't have the funds.
Maybe there is some way to repel the animals inexpensively and without killing them.
Questions of conservation vs livelihoods are incredibly complex, not least in the Sundarbans area (have worked with farmers in this region) - complex in a way you don't see with human-animal conflict in other parts of the world. We are not talking about a few hundred french farmers and wolves here, but rather livelihood of hundreds of thousands.
It is probably one of the most densely populated areas lying so close to a tiger reserve. The population around the reserve are some of the most climate stressed farmers in the world (facing soil salinity and monsoon variability due to climate change) and areas inside the forest reserve have traditionally been an important source for additional livelihood (honey collection, fishing, etc.).
Farmers settled in these areas were also in part displaced during the colonial era from Bihar and other parts of West Bengal, in essence forced to live in the delta - now of course these are their villages and home towns.
To add to the challenge there is an incredible scarcity of food sources for tigers in the Sundarban reserve, with few other large animals, which is put forward as part of the reason they have (unlike tigers elsewhere) have made it a practice to treat humans as food sources. They are adept swimmers and do attack people in boats meaning that even fishing can be a risky endeavour for farmers.
All in all, the conflict between people and the tigers living in Sundarban is pretty complex and in no small part caused by people outside of the delta (including the British, the increased urban population of Kolkata and surrounding districts, etc.).
You wont live in a village close to them, as Indian government dislodged the Adivasi of Baiga and Gond tribes, who traditionally lived in the area, that is now a wild life reservation in Kanha, Similipal and Odisha Gondwana.
Those people got some pennies for the eviction, barely enough to buy a few days food in big city, but nowhere enough to buy land to live on.
I can really understand that those people join the Naxalite Maoist Army to fight Indian government to get their country back from investors, tourist and other western parasites.
"Listen lads, there's only a few of us, and 7 billion of them. They could stand to lose a few of their numbers. What say we help ourselves to a smooth-ape buffet lunch?"
Would like to know some of the methods that caused the turn-around. "Conservation" doesn't tell me much. Great new though, are these tigers truly "wild"?
They're wild alright. One 'method' that's widely credited is the unofficial policy of shooting poachers on sight. Oldish article, but there's some more detail and context on the situation at Kaziranga (today used as a role model at other parks) here:
Fascinating read. At the start I figured it was as simple as "poachers are bad people," that they're just profiteers, but the situation is far more deep-rooted and complex, involving war in neighboring areas and the funding of the park coming from conservation of tigers, which the locals hate. So much could be solved if the people living there just had a legal way to make money.
> Would like to know some of the methods that caused the turn-around.
I would have liked to see the raw numbers for each conservation area and the methodology used for the estimation. I am sceptical of the forestry officials as at least some of them were in cahoots with poachers and the trafficking of tiger parts to East Asia.
Also, India needs corridors rather than isolated wildlife islands which is what results in lack of genetic diversity. If I recall, there was an Indian biologist who proposed a 50 year plan to slowly connect the remaining wildlife parks together with thin corridors that ran between populated areas. It would permit animals to safely traverse long routes and thus increase genetic diversity.
Apparently above 1500 individuals (out of some 2200) have been photographed using automated cameras and the rest extrapolated from there. Extrapolation methods were one of the reasons for wildly fluctuating numbers in some reserves previously.
If you're in India you probably could get access to the actual photos via a request to the right department (Ministry of Forest and Environment for a start) or in a pinch RTI.
https://en.wikipedia.org/wiki/Tiger#Reproduction says usually 2-3 cubs per birth, mortality rate 50% in two years. They separate after two years. If the tigress only has one litter on the go at a time, that puts a limit of about half a cub per year.
The reported numbers come to about 1/10 of a cub per tiger per year, or 1/5 of a cub per tigress assuming equal numbers. If two thirds of them are sexually mature, then 0.3 cubs/year each.
That's close enough to the upper bound that it seems implausible to me, but these numbers aren't reliable enough for strong conclusions.
A number of the tigers are on nature preserves, with help from scientists/conservationists. That would reduce the infant mortality rate since these tigers aren't really "in the wild".
1-6, usually 2,3. If unsuccessful (all cubs die) the female can give birth about twice a year. If successful (raised cubs live) the female gives birth every 2 to 2.5 years.
> What is the mortality rate on those babies?
> 50% before two years, but the female reproduces faster if she loses her cubs compensating for some of the loss.
> Is this definitely not just greater efforts to count tigers?
It would require about 60 successful litters per year.
Call me skeptical, but I think the underlying explanation most likely is a change in counting methods (or, more probably, an error). With the rise of China, the demand for tiger bones has only increased. For a local villager, one tiger's bones are more than what he'd earn in several years, so it provides a tremendous economic incentive to kill tigers. The easiest (for the killer) methods are to poison them or electrocute them at the watering hole. It is really sad.
Perhaps, but China has also made great strides in the preservation of animal species, like the giant panda and golden monkey. True, there are still some small segment of the population, mostly in villages, which desire rare animal parts. However, these are the exception in China and the preservation of these animals contribute greatly to tourism.
I hope to see China as a role model for preservation of animal species. The recent(ish) loss of the Baiji[1] hopefully sent a wake-up call to the Chinese government.
Here in Australia we've historically had a terrible track record for this ("There are 23 birds, 78 frogs, and 27 mammal species or subspecies strongly believed to have become extinct since European settlement of Australia."[2]), but we're hopefully getting better. I recently visited some of the Tasmanian Devils who are being bred on the mainland, in isolation from the Tasmanian population, due to [3]. They seem hale and hearty (and very cute, though I wouldn't want to cuddle one)
Does China do anything to stop the import of poached animal products? They protect their own native species (nowadays, anyways... their native tiger is likely extinct in the wild), but don't make similar efforts species from other areas. Their ivory and tiger trade are huge international problems for modern conservation efforts.
Glad the tiger population are doing better!
Was a proud WWF supporter on saving tigers until I found out that their VP took out million salary($100k+) not exactly wellfare.
I think a lot of charity's function this way. You could argue that paying towards the VP salary is helpful because of his potential ability to increase revenue through fund raisers which eventually provides even more support to the WWF. Some charity's also mention that a certain % is guaranteed to directly support the cause. Not sure what % that is for the WWF though.
I used to donate to WWF. I stopped after I watched the ARD greenwashing documentary which alleged that WWF accepted money from large corporations in return for certifying their activities as "sustainable".
I visited Kaziranga in Assam, India which has the highest density of tigers. The local rangers said they don't get any help from these aid organizations. Looking at WWF activities in detail suggests they do almost nothing for the local people. The WWF leadership ( http://www.worldwildlife.org/about/leadership ) has no representation of people who actually live in the areas which are key to survival of these species. In my opinion, that dooms it to failure. My belief is that to save tigers, you have to provide the people who are poaching tigers with a viable financial alternative. I would much rather the person taking a photo of a tiger in the jungle be a genuine local rather than a corporate employee doing greenwashing. http://tigers.panda.org/t2/mars-cindy-jiang-joins-wwfs-tiger...
I guess my point is that giving for animal conservation is very inefficient and nt at all transparent. If you want to protect the animals, push for things that will help the economies grow in the countries with the animals. Animal poaching and habitat destruction are usually results of poor people seeking a way to make a living. Rich countries have the best environmental policies and records. Protecting the environment is a matter of wealth.
Also, don't support biofuels and speak out against them and especially subsidies that favor biofuel production.
Isn't this the same issue as CEOs of private enterprises making millions? If that is the market rate of someone with those skills, shouldn't that be what they're paid?
2 Qs: How have tiger-human relations/(co/non)existence changed in the last few decades? Are there more/different interactions in rural, suburban, urban (?) settings?
There are very few of these animals left - just 163 at the last census. One year a single dingo breached a fence and killed 10% of the population.
They all used to be in a single location, but a second location has been set up and some animals seem okay there. Populations are gradually increasing. The numbers dropped to about 90 animals, and that seems like a severe bottle-neck. I'm curious whether that'll contribute to genetic flaws in later populations.
http://www.environment.gov.au/biodiversity/threatened/public...
http://www.edgeofexistence.org/mammals/species_info.php?id=9
http://www.arkive.org/northern-hairy-nosed-wombat/lasiorhinu...
https://en.wikipedia.org/wiki/Northern_hairy-nosed_wombat