The monitoring method should be ideally the same for all surveys, but has some variations for various reasons.
In contrast, the method for data processing is completely the same.

Camera-trapping devices were set at the height of 150 (or 200) cm to trees standing at the side of forestry roads.
They had an depression angle so that they could cover all mid-to-large-sized mammals passing through the road.
The device model used was 'YoyShot G3' or 'YoyShot Digital'. They are set to operate for 24 (or only night dark) hours.
The period of a survey was from two to four weeks. Mid-term checks were made once or twice.
More than six devices were used for a survey.
They were positioned more than 500 m apart from each other, so that one animal could not be photographed at different points.
For details, see A manual for mid-to-large-sized-mammal surveys using forestry roads (in Japanese).

The same data processing method was applied to all the surveys. See Examples.
All the data were checked with photos by Hirakawa. All the wildlife photos after 2009 were digitalized and stored.

For details about where the survey sites are and when surveys were conducted, see the result pages for each survey site.
The page for raccoons and that for martens and sables uses the results obtained by Hokkaido Institute for Environmental Sciences.