Hawaiian honeycreepers are in Peril-Why the native forest birds may become extinct.

Editor’s Note: This is the fourth in a six-part series.

HAWAII-It is considered the “global epicenter of imminent extinctions”  for plants and animals; just since the 1980s, 10 unique birds have disappeared. Among some of the most threatened species are a native group of forest birds known as honeycreepers (Drepanidinae) that have evolved in the absence of avian malaria. 

As you can see (below), these beautiful and fascinating birds have evolved  a remarkable array of distinctive morphologies.

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Family Drepanididae (Hawaiian Honeycreepers). *Note* Not all species are shown.

[VIDEO] Are you looking to see what a Purple,Green, Shining, Golden collared or Red-legged honeycreeper looks like?

Hawaii has more extinct birds than anywhere else in the world

Hawaii has more extinct birds than anywhere else in the world

Honeycreepers have suffered catastrophic decline in recent decades due to:

  • Habitat loss
  • Introduction of alien plants and animals
  • Avian disease

The accidental introduction of the southern house mosquito Culex quiquefasciatus– a non-native species –  into Hawaii  (1826) has allowed avian malaria and avian pox to spread, putting 33 species of the 42 remaining birds species in danger of extinction.

Clearly, the rapid loss of native island floras and faunas is a huge cause for concern among scientists.

We have five, 10, maybe 15 years before we start seeing more declines…but some of these species don’t have that much time and I don’t want to see another species become extinct in my lifetime. 

Pete Marra, director of the Smithsonian Institution’s Migratory Bird Center .

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The introduction of avian malaria (Plasmodium relictum) to the remote Hawaiian Islands is believed to have played a major role in the decline and extinction of several native bird species. Now, less than half of Hawaii’s previously extant species of honeycreeper still exist.

Symptoms include:

*Anemia. The loss of red blood cells leads to a…

*Lack of oxygen and progressive weakness.

*And eventually deathbirds that have never had tolerance to malaria can get it very quickly and die from it. Mortality in many native species can range from 50 to 90%. In contrast, mortality in introduced bird species appears to be negligible.

THE MAUI PARROTBILL (PSEUDONESTOR XANTHOPHRYS) IS ONE OF THE HONEYCREEPERS THAT IS MOST THREATENED.

THE MAUI PARROTBILL (PSEUDONESTOR XANTHOPHRYS) IS HIGHLY SUSCEPTIBLE TO MALARIA AND IS ONE OF THE HONEYCREEPERS THAT IS MOST THREATENED.

Species-differences in susceptibility to disease.

Example:`I`iwi vs`Apapane

The ‘i’iwi (A) is very susceptible to malaria, whereas the ‘apapane (B) less so.

*NOTE*  The differences in disease susceptibility are for reasons yet to be determined

Nature conservancyToday, threatened by habitat destruction, introduced predators and avian diseases, the ‘i‘iwi is extinct on the island of Lāna‘i, and is considered extremely rare and vulnerable to extinction on O‘ahu and Moloka‘i.

Iiwi honeycreeper

A)’I’iwi honeycreeper.  The ‘I’iwi is easily Hawaiis most recognizable forest bird. As well as habitat loss, Hawaii’s massive bird losses are blamed on introduced mosquitoes, which carry diseases like avian malaria.

'Apapane honeycreeper

B) ‘Apapane honeycreeper

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