Species translocation--capturing animals in one place and releasing them in another--is a widely used conservation method for establishing or reestablishing populations of threatened species. However, translocation projects often fail when the transplanted animals fail to thrive in their new home. A new study from The Condor: Ornithological Applications demonstrates how close monitoring of the animals being released into a new area is helping wildlife managers gauge the success of their effort to save the Ridgway's Hawk of Hispaniola.
Ridgway's Hawk is a critically endangered raptor endemic to the Caribbean island of Hispaniola. Since 2009, the Peregrine Fund has translocated 104 nestlings from the species' stronghold in a national park to a protected resort area called Punta Cana 130 kilometers away. They monitored the birds after their release, tracking their survival and breeding success, as well as collecting the same data on 36-110 breeding pairs per year in the original national park population. Survival rates were high in both locations, and more young hawks began breeding on the resort property, probably because more territories were available due to the birds' low numbers.
Lead author Chris McClure of the Peregrine Fund and his colleagues believe that the "soft release" method they use with the translocated birds, involving an adjustment period where young birds are allowed to come and go freely but are provided with food, has contributed to the success of the project. Post-release monitoring has been a valuable tool for gauging their success and planning future conservation efforts, and they hope that more wildlife managers will consider incorporating this into their plans when seeking funding for translocation projects. "Our results show that the new population of Ridgway's Hawks in Punta Cana is taking hold, but we only know that because of the hard work of our staff and volunteers in tracking these birds," says McClure. "I think our study is a great example of monitoring to ensure that conservation goals are actually achieved."
"The paper is a good example of the important role of post-release monitoring in translocation projects," adds Massey University's Doug Armstrong, an expert on reintroduction programs who was not involved in the study. "It is easy for people to invest a lot of effort into well-meaning but ineffectual translocations projects if they aren't monitored. This paper illustrates how state-of-the-art methods can be applied to provide clear and useful information of post-release survival and recruitment."
"Successful enhancement of Ridgway's Hawk populations through recruitment of translocated birds" will be available October 25, 2017, at http://www.
About the journal: The Condor: Ornithological Applications is a peer-reviewed, international journal of ornithology. It began in 1899 as the journal of the Cooper Ornithological Club, a group of ornithologists in California that became the Cooper Ornithological Society, which merged with the American Ornithologists' Union in 2016 to become the American Ornithological Society. In 2016, The Condor had the number one impact factor among 24 ornithology journals.