Many of O’ahu’s native bird species are gone. The Polynesians and westerners brought in too many invaders: pigs, rats, mongoose, cattle, goats, chicken and, worst of all, avian malaria-transmitting mosquitoes. Island ecologies are notoriously fragile. and the Hawai’ian Islands proved to be no different. Today, native bird species, especially O’ahu’s amazing songbirds, are mostly gone. Invasive species dominate the avifauna now.
The invasive species are mostly escaped cage birds. And they are certainly colorful enough. But they came loaded with the avian malaria Plasmodium protozoans. The invasives had evolved tolerance to the disease; the native Hawai’ian birds had not. When mosquitoes were introduced, they carried the disease from the non-native to the native birds, with tragic results. So look at these handsome introduced birds with a critical eye. In no particular order, here’s a sampling of the non-native, introduced songbirds:
A difficult species to find. This small flock was at a baseball field and park in a Honolulu suburb.
One of two established parakeet species on O’ahu. Very common but not especially cooperative.
Common Waxbills are nearly invisible on the ground. They also feed on grass seeds directly from the stems. If you want an exercise in futility, attempt photographing teeny little birds in high grasses when the wind is blowing 25-35 mph.
One of two established species of Bulbuls. The flocks are delightfully noisy.
More accurately, the exceedingly Common Myna. They are everywhere on the island.
Less common than some of the others, but present in numbers in the Honolulu city parks.
Old World sparrows don’t walk; they hop, and Java Sparrows take big hops. WC has better images of the species, but they aren’t as much fun.
That’s a sample of the introduced species that now breed on O’ahu. Tomorrow we’ll have a look at some of the endemic species that survived or that, like many Alaskans, spend part of the year in Alaska an part of it in Hawai’i.