Columbia subject headings:
Harvard subject headings:
Bird populations--Congresses.
Birds--Conservation--Congresses.
Island animals--Congresses.
Sea birds--Congresses.
Sea birds--Conservation--Congresses.
Sea birds--Ecology--Congresses.
Princeton subject headings:
Bird populations--Congresses.
Birds--Conservation--Congresses.
Island animals--Congresses.
Sea birds--Congresses.
Sea birds--Ecology--Congresses.