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The article says that the numbers increased from "1,706 in 2011 to 2,226 in 2014". So, 520 baby tigers in 3 years?

How many baby tigers per birth?

What is the mortality rate on those babies?

Is this definitely not just greater efforts to count tigers?




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".


> How many baby tigers per birth?

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.


>So, 520 baby tigers in 3 years?

No, its 520 babies after you subtract the dead during those three years. Its 520 more tigers total.


It's 520 (baby tigers - dead tigers).




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