Postfledging dispersal of red‐fronted parakeets ( Cyanoramphus novaezelandiae ) from a fenced mainland sanctuary

TitelPostfledging dispersal of red‐fronted parakeets ( Cyanoramphus novaezelandiae ) from a fenced mainland sanctuary
MedientypJournal Article
Jahr der Veröffentlichung2021
AutorenIrwin, E., K. Kikillus, R. Gray, R. Empson, and N. Nelson
Volume3
Veröffentlichungsdatum2021/01/13
Zusammenfassung

Abstract Translocations are an important tool for conserving species at risk of extinction from a range of threats. However, an understanding of the life history of many threatened species prior to translocation is often lacking despite being critical for translocation success. For example, dispersal away from the release site in the years following a translocation—particularly when a protected release site is surrounded by unmanaged habitat—can result in failure to establish a self‐sustaining population; successful translocation practice must therefore include an understanding of a species' dispersal patterns. We examined the postfledging dispersal of 22 juveniles reared from a population of red‐fronted parakeets (Cyanoramphus novaezelandiae), or kākāriki, translocated to a mainland sanctuary in Wellington, New Zealand, 6 years prior. The translocation was one of the first of this species to mainland New Zealand and presented several unknowns, in particular whether a population would establish in a sanctuary bordered both by contiguous forest as well as suburban areas. Juvenile kākāriki were radio‐tracked and their location recorded once a day, 5 days per week, for 6 months or until the transmitter battery was exhausted. Approximately one‐third of radio‐tracked juveniles that dispersed outside the sanctuary were killed by predators. Kākāriki postfledging dispersal beyond the sanctuary was male‐biased, possibly driven by inbreeding avoidance, and distance dispersed decreased with increasing body condition. As species are increasingly being translocated back to mainland New Zealand, information gained in this study helps to fill a fundamental knowledge gap regarding dispersal behavior in a mainland context.

Viele bleiben in einem Umkreis von ~400 Meter um den Geburtsort, während einige - vor allem Männchen in weniger guter körperlicher Konstitution bis zu 4km entfernt vom Geburtsort sich niederließen. Vor allem Männchen siedeln sich größere Strecken entfernt von ihrem Geburtsbereich an.




'Es spielt keine Rolle, wie schön deine Theorie ist. Es spielt keine Rolle, wie klug du bist. Passt sie nicht zu den experimentellen Ergebnissen/Beobachtungen, dann ist sie falsch!'. {nach Richard Feynman, Nobelpreis für Physik 1965}