mike@uhunix1.uhcc.Hawaii.Edu (04/30/91)
I have recently come by some fascinating information about populations of "released birds". I had earlier speculated that Huricane Ewa had ripped open many of the outdoor aviaries popular in back yards on the Windward side of Oahu some years ago. It appears now that we have inherited a legacy of parrots. This weekend a friend had a chance to talk to a local expert in established populations of parrot species on Oahu. Following is a summary of what he remembers from several hours of conversation while attempting to retrap an escaped African Grey in a tree in his yard. Before anyone screams, the person doing the trapping is properly licensed to attempt to trap these birds when the state gets complaints. He gets first crack at reclaiming the bird. Second crack goes to a team armed with shotguns (apparently not widely advertized pest control). Estimates of the parrot population of Central Oahu place the breeding established level of birds at about 450. They exist mostly in small colonies which have favorite roosting trees they return to at night. At least 20 species are represented by breeding populations in the wild. Papaya growers are already suffering crop damage as some populations have become agricultural pests. One large parrot can strip a papaya tree in ten minutes. Totally ignoring the populations of various love birds and cockatiels too numerous to mention, the species listed as having known established breeding populations include: (please forgive the approximate names and descriptions): ------- A number of types of Macaws A range of species of Amazons The African Grey Cockatoos including Sulphur Crested, Umbrella, "Large White",and a small species that has a pink and purple crown. Many types of Conures, usually reported for their noise pollution. ------- In a recent case, a tree in upper Manoa was blown down during a wind storm. It had three pairs of breeding African Ringnecks (dark green with a yellow ring around the neck and red patches under the wings). In one nest were discovered five babies which were at last report alive and being hand raised. Estimates place the rural population (a relative term on Oahu) at 250 birds minimum and the population in Honolulu proper at 200. These are counts of the known populations in established roosting trees. I am convinced these populations probably started as the result of wholesale destruction of aviaries in the winds of Huricane Ewa nine years or so ago. In that event established breeding pairs were torn from their backyard cages and driven miles inland. In the mountains of Central Oahu can be found a very wide range of environment from dense rain forest to dry grasslands with scrub trees, so they only had to take their pick and settle down. In these Kapu or prohibited areas one can only imagine what the populations must now be. Here we are discussing only the populations that have been reported by residents to the state and checked out by onsite visits. It appears Oahu is rapidly becoming a very strange island in terms of established bird populations! It looks like we may soon have some interesting conflicts as the shotgun crews show up to "remove" a species that turns out to be endangered. I frankly do not know if any of the escaped birds that have established in the "wilds" of Oahu qualify as endangered or if only hardy common species are present. I also do now know what would happen if a bird ended up with status as "endangered" and "accidentially introduced" and "agricultural pest" and "non-native" all at once. It appears to be an interesting legal problem.
smith@uhccux.uhcc.Hawaii.Edu (Gordon Smith) (05/06/91)
In article <12722@uhccux.uhcc.Hawaii.Edu> mike@uhunix1.uhcc.Hawaii.Edu writes: > > I have recently come by some fascinating information about >populations of "released birds". I had earlier speculated that >Huricane Ewa had ripped open many of the outdoor >aviaries popular in back yards on the Windward side of Oahu >some years ago. It appears now that we have inherited a legacy >of parrots. > >having known established breeding populations include: > >------- > >The African Grey > >Cockatoos including Sulphur Crested, Umbrella, "Large White",and > etc... Introductions of exotic (non-native) species has long been a major problem in the Hawaiian Islands, beginning with the anicient Polynesians who first settled here (bringing with them chickens and pigs). The problem is that with the exotics come unfamiliar diseases and habitat degradation. Hawaii has more threatened or endangered native species than any other statee in the union, and there is a long, long list of known extinctions.. It didn't begin with Hurricane Ewa, but I'm sure that the storm added to the problem both with additional accidental introductions and habitat destruction. It is difficult to find a native land bird on Oahu. ALL of the birds that you find exept in the most remote, high elevation areas are introduced - accidentally or otherwise.. Many people born and raised here have never even seen a native land bird. Gordon Smith smith@uhccux.uhcc.Hawaii.Edu