The Marbled Murrelet has a fascinating breeding behaviour, which is very unusual for a pelagic bird species. The species breeds offshore, in old-growth and late successional coniferous forests, where the birds build their nest high in the canopy of old coniferous trees. The nests are usually found within 60 km of coast in western hemlock (Tsuga heterophylla), Sitka spruce (Picea sitchensis) or Douglas fir (Pseudotsuga menziesii) being their most important nest trees. Less the frequently the Marbled murrelet, breeds on bare ground, usually on inland slopes, in boreal tundra regions along sea coasts. It took science very long to discover where these birds were breeding, until keen birders observed adult Murrelets flying landinwards over the vast old growth forests.