Over the past 50 years, the tiger population has shrunk substantially, and some breeds of tigers have even gone extinct.
"The population of tigers in India is declining due to habitat loss, prey depletion, poor genetic diversity, habitat degradation, the illegal wildlife trade, man/animal conflict, tourism, and lack of a wildlife management and protection infrastructure."
If more and more animals immigrate into a habitat, all lives of the animals are affected because then there is a greater fight over food. If a habitat has a large number of tigers already, and then more immigrate in, the population will start to shrink down to a certain size because the habitat can not provide enough resources. On the other hand, if a population of tigers immigrates into a habitat with a smaller number of tigers, the fight for food is not as hard and they can live on.
When a population emigrates out of a population, it is usually because of low resources, there is a chance that the population will grow again once new resources are found, but In the moment, the population does not have enough food resources to survive.
The birth rate of the tiger had a drastic increase recently. Birth of healthy tigers increased 30% in Africa recently. If more and more tigers are being born, more and more resources will need to be in their habitat, but there are only so many recourses that can be available so at one point the habitat will reach carrying capacity.
The tigers have been known to be dying off a lot more than usual. If the tiger population dies off then there will be more resources for other populations and will cause an increase in the birth rate of similar animals.
The growth of the tiger population is going up, while it has just recently started doing that, it used to be very low. Based on resources and the amount of resources tigers need, the population will soon level out if it does not shrink.
Because the population is currently rising, there will be a time soon when resources start to run low due to all of the tigers needing them to survive. As resources start to disappear, so will the tiger population, but once the population goes down, more resources will become available and the population will rise again.
The logistical growth of the tiger population is currently in the stage of rising. Soon the population will level out and then start decreasing due to the limit of resources. This cycle will be repeated over and over, until one day if the population goes completely extinct.
Tigers do not have much competition for food because they are such large and deadly animals, and they don't have any animals hunting them either because they are at the top of the food chain. As goes with other animals, parasites and diseases can also affect the tiger population if contracted in enough animals.
Another limiting factor for the tiger population would be the fact that a lot of tigers are being killed for human purposes such as clothing and jewelry. There have not been any natural disasters or unusual weather that has put a dent in the tiger population, human activities are the main reason for unnecessary deaths among tigers.