Cleland Island and other smaller islands in southeastern Clayoquot Sound provide important habitat for four species of breeding birds. Fifty-four pairs of American Black Oystercatchers were recorded in 1986; which is 1% of the global population, and in some years, as many as 57 pairs have been detected on Cleland Island. In 1988, surveys found 1,687 pairs of Glaucous-winged Gulls, which is about 1% of the North American population. Also in 1988, 207 nesting Pigeon Guillemots (2% of the Canadian population) and 5,700 nesting Leachs Storm-Petrels (1% of the Canadian component of the eastern Pacific population) were recorded. Cleland Island is a diverse seabird colony as in addition to the species already mentioned, Cassins Auklet, Rhinoceros Auklet, Tufted Puffin, and Fork-tailed Storm-Petrel also breed here.During the summer, the southeast portion of Clayoquot Sound (particularly southeast of Vargas Island and southeast of Flores Island) hosts substantial numbers of Marbled Murrelet (a nationally threatened species). In 1982, 4,500 birds were recorded, whereas in 1993, 2,622 birds were recorded. This most recent survey still represents 5% of the Canadian population. The difference in numbers may be a result of climatic variation and not actual longer-term changes in population. Conversely the loss of old-growth forests to logging, along with other factors, may be causing a genuine decline.
Large numbers of Black Brant use the eelgrass beds; 4,000 birds were recorded in April 1970, but in 1989 only 480 birds were seen. Thousands of White-winged and Surf scoters can be seen while moulting or migrating in early spring. It is likely that over 10,000 waterfowl of various species gather here in spring, but this has not been confirmed.