The amount of data and information gathered can be incredibly insightful. Scientists can receive several daily pinpoint locations on animals so that a more accurate account of their daily movements can be monitored. Cost considerations used to be a major factor in the use of satellite technology. However, current satellite collars are much cheaper than there predecessors and the batteries that run them are much more effective. Battery life can be influenced depending on the number of options the collar processes.
Some collars can actually utilize solar power.
The animals do not simply role over and let you place collars on them. The methods for immobilizing animals usually include a dart gun and a tranquilizer. However, bears can run in excess of 30 miles an hour so sometimes you have to dart them from the air. This adds a definite cost to the project and inherently increases the danger or risk factor for the people involved. Once the animal is down it must be handled in a way that will not result in injury and all attempts are made to reduce the animals stress.