One issue is the harassment of wildlife. When used too often, however, this strategy may cause birds undue stress. Another issue is trampling. Birders often venture off the trail in pursuit of birds, damaging the underlying vegetation and soil in the process. To reduce this problem, park managers have constructed a raised boardwalk around a heavily-used bog at the summit of Doi Inthanon.
Litter is also a concern.
Most of the birders we surveyed were conscientious about keeping the park clean. But Phil Round, an ornithologist and conservationist in Thailand, says that even when litter is placed in garbage bins, it may end up being thrown into the woods and burned. Similarly, air pollution can be a problem on busy weekends when up to 5,000 vehicles travel to the summit each day. Fortunately, some tourists use public transport, especially trekkers and birders. Social Impacts Besides its economic and environmental impacts, ecotourism can have social effects.