I find beavers to be very interesting animals. This articles provides some very interesting information regarding to the beavers population and lifestyle.
This article list many uses the beaver has to nature, which includes how they create the world's most valuable ecosystem and how they are the cause of the survival of many endangered species. A beaver's dam has more uses then water control, it is able to filter the water and remove the toxins so water can be cleaner in the wet lands after it passes through the dam.
Beavers will usually mate by the age of three and have one mate for life. The first litter will usually have only one baby but after the first they can how up to four at a time. The beaver population won't over populate because beavers will only mate once a year. Also the beavers are not a main food source for any animal. But beavers may be attacked by anything from bears to dogs to birds. Unfortunately the most common killer of beavers is trapping which in my opinion shouldn’t even happen.
I found this to be a very informative article and I would recommend it to anybody wanting to learn about beavers.