In New Zealand, conservationists are studying the nesting behavior of Fantails in hopes it will glean insights into the behavior of rare, Endangered birds.

Many bird species are on the brink of extinction due to the presence of invasive rats. So, it should come as no surprise that within conservation, rare birds are a high priority. Unfortunately, their rarity also makes them much more difficult to study and protect. These at-risk species have low population numbers and are often found in remote, hard to access locations such as islands and understanding how invasive rats impact their breeding success is crucial to protecting them. That is why researchers in New Zealand decided to explore the impacts of invasive rats using a common bird species that isn’t endangered.  

That bird species is the Fantail. It is commonly seen throughout New Zealand in high population densities. The researchers believed that by exploring how invasive rats impact Fantails breeding success and population densities this knowledge and insight could then be applied to the conservation of birds that are at risk of extinction. An excerpt from the study says: 

To quantify the link between ship rat abundance and survival of small, endemic birds we investigated the prevalence of rat predation on nesting New Zealand Fantails (Rhipidura fuliginosa placabilis), and its importance relative to other risk factors such as nest microsite. We surveyed 106 nests across forested reserves in Wellington City, New Zealand.” 

The nest sites were determined based on existing knowledge of Fantail breeding and cameras were placed at each of these locations for observation. Chew cards were used at each location to determine rat density. The results showed that Fantail nesting success dropped to a mere 20% when the chew card demonstrated an abundance of rats exceeding 45%. 

Fantails are a highly resilient and adaptable species. Yet, even when invasive rat populations in a given area are low, their breeding success is still adversely affected. This speaks volumes about the tremendous harm invasive rats are causing to less adaptable and imperiled small bird species. The results of the study suggest that keeping invasive rat populations low if not removing them completely is the key to protecting native bird species. This insight will help to inform conservation efforts and provide a small emblem of hope for Endangered bird species all over the world.  

Source: Predator Free NZ
Featured Photo: A New Zealand Fantail. Credit: Bernard Spragg