Heading North Mammals Terrestrial migration is made difficult for caribou by roads and other human structures which they are afraid to cross or get killed crossing. One of the problems facing wildlife in the oceans is that governments can only dictate the waters allocated to them. Most governments have policies such as the Australian Whales are Protected policy. However as whales are migratory animals they run into dangers from whalers outside of the protected waters. Wales and other aquatic animals often run into difficulties with pollutants even when in protected areas.
Wetlands are crucial for absorption of pollutants, and migration of birds and aquatic animals.