Photograph or Video Analysis Method
Population counting gets a little more interesting when you try to study animals in the wild. Unlike plants, most animals have the tendency to flee or fight at any sign of danger. Neither of these instincts are good when you are a curious scientist. To get accurate estimates of animal populations you must be more creative.
One technique which allows you to keep your distance and gather information about groups of animals is the photograph or video analysis method. This is ideal for birds flying in groups overhead or herds of large animals such as caribou. If a herd can be photographed from an aircraft, it can be analysed later on the ground. If a group is spread over a wide area, numerous photographs may need to be taken.
To simplify the counting task, you can lay a grid over the picture and count the amount of organisms in each grid square. Record each number and add up all the numbers to get a total for the picture. When using video, the ability to analyze the film frame by frame makes counting the specimens a realistic task.
Radio Tracking Method
To better understand a species' range, the radio tracking method is employed to monitor the day to day movements of a species.
In Canada's western Rockies and grassland areas, the grizzly bear population is being carefully studied. Ecologists are worried about the decline in the population of the Grizzly bear in these areas. At one time, the grizzly population was around 6000 bears in Alberta. Today, there are approximately 800 remaining. Management and conservation of the bears needs to be based on a thorough knowledge of the species. To study the bears habitat, a few of the bears have been trapped, fitted with radio collars and released.
Scientists now track the bears with radio receivers from the ground and air. This provides scientists with a clear profile of the complete habitat and movements of the grizzly without disturbing their natural movements.
If human development is proposed for areas that overlap with the grizzlies' range, efforts can then be made to allow the bears' habitat to remain undisturbed.