Comment on "On the regulation of populations of mammals, birds, fish, and insects" IV.

Sibly et al.'s (Reports, 22 July 2005, p. 607) contention that density dependence acts strongly on low-density animal populations irrespective of body size contradicts many long-term studies of large mammals. Their findings were distorted by harvest records, which may poorly reflect population trend. Omitting unreliable data, their massive data set is reduced to only one case for large mammals.