Tuesday, 16 May 2017



Art. # 262


A Blue Planet Tour reveals Out-Of-Range bird species

Text by Stefan Rust
Photo by Peter Pack

(In terms of the Geneva Convention the copyright of these texts belongs to Stefan Rust)

In May, this year, excitement rose among tour participants and the BirdsConTour guide after some interesting bird species sightings.

In biology, the range or distribution of a species is the geographical area within which that species can be found. In case of mobile species also described as natural range.
During a 15-day Blue Planet Namibia Tour, organized by Blue Planet and Pack Safari and led by BirdsConTour, five Out-Of-Range species were located; Yellow-billed Oxpecker on Farm Omandumba, Erongo (south of its natural range), White-bellied Sunbird on the Otjitotongwe Cheetah Farm (west of its natural range), Malachite Kingfisher in the Khowarib Gorge in the Hoanib River (south of its natural range), Antarctic Tern in the Walvisbay Lagoon (north of its natural range).
Spotting an out-of-range bird species is always exciting for any tour participant, but what causes a bird to arrive in unexpected locations?
Exactly why accidental birds appear so far from their regular ranges is somewhat of a mystery, but there are several possible explanations.
Weather: Storms with their turbulent air currents can force flying birds far off their
               regular route.
Inexperience: Juvenile birds making their first migration can become lost.
Genetic abnormalities: Some birds may be misdirected by impairments in their
                                     migration sense of the Earth’s magnetic field.
Better resources: Once resources for food, nesting and potential mates become scarce
                            in a particular area due to whatever reason, birds move out of their
                            natural range to find new resources. 

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