A new study confirms that bigger and stronger silverback gorillas have more success finding mates and raising offspring. The study, which is published in Journal of Human Evolution, was conducted over 12 years in Republic of Congo\'s Nouabalé-Ndoki National Park by researchers from the Max Planck Institute and the Wildlife Conservation Society (WCS). The researchers found a positive correlation between male size and reproductive success. \"The bigger the adult male, the more mates it had,\" explained a statement issued by WCS. The authors used the study to call for more funding and highlight the importance of protected areas like Nouabalé-Ndoki. \"Studies such as these—ones that examine the subtle dynamics of gorilla interactions—are only possible in the stable conditions created in protected areas such as Nouabalé-Ndoki National Park,\" said James Deutsch, Executive Director for WCS’s Africa Program, in the statement. Lowland gorillas are the more abundant of two surviving species of gorilla. Nevertheless their numbers have declined in recent decades due to habitat loss and poaching. Thomas Breuer, Andrew M. Robbins, Christophe Boesch, Martha M. Robbins, Phenotypic correlates of male reproductive success in western gorillas, Journal of Human Evolution, Volume 62, Issue 4, April 2012, Pages 466-472, ISSN 0047-2484, 10.1016/j.jhevol.2012.01.006.