...rather than colonies, however. Carrick, Robert. [THE REGULATION OF NUMEERS IN NATURAL POPULATIONS.] SOCIAL AND ECOLOGICAL FACTORS IN POPULATION REGULATION OF THE AUSTRALIAN MAGPIE GYMNORHINA TIEICEN. Proc. l6th Intern. Congr. Zool. 3: 339-34l. [l9 64.] WR ll5: 58 [Div. Wildl. Res., CSIRO,...