A portrait showing the breed's distinctive headThe Perro de Presa Canario or 'Canary Dog' is a large-size dog with a thick and muscular body. The head is broad, massive, square, and powerful brachycephalic shape. Proper head and good expression are part of the breed standard, and are manifest in the best breed specimens. The ears are normally cropped, both to create a more formidable expression and to prevent damage while working with cattle.