The mesopredator release hypothesis predicts that reductions in top-predator abundance in a community will increase the abundance or activity of smaller ‘mesopredators’, and increase predation pressure on mesopredator prey, including bird nests. Top predators have been extensively controlled in rangelands managed for sheep in South Africa, because top predators prey on sheep. To test whether this control of top predators has increased nest predation risk for breeding birds in rangeland landscapes, I compared nest predation rates between rangeland areas subject to predator control, and large protected areas with no predator control. An artificial nest experiment found that nest predation by mammalian mesopredators was non-significantly higher in rangeland areas, providing weak support for increased predation by mammalian mesopredators as a consequence of mesopredator release. However, nest predation rates on natural nests of a suite of nine species did not differ between rangeland and protected area landscapes. Thus, control of top predators does not appear to reduce bird nesting success in this system. This result may reflect complex interactions between mammalian mesopredators and other predators of birds' nests, particularly snakes.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 42 • No. 2