Climate change threatens Hawaiian honeycreepers


From the United States Geological Survey:

Jeepers creepers: Climate change threatens endangered honeycreepers

Deadly diseases may move up Hawaiian mountains to birds’ refuges

As climate change causes temperatures to increase in Hawaii’s mountains, deadly non-native bird diseases will likely also creep up the mountains, invading most of the last disease-free refuges for honeycreepers – a group of endangered and remarkable birds.

A just-published U.S. Geological Survey (USGS) review discusses the likelihood of a forthcoming “disease invasion” by examining the present altitudinal range of avian malaria and pox, honeycreeper distribution, and the future projected range of diseases and honeycreeper habitat with climate change.

At one time, the Hawaiian Islands had no mosquitoes – and no mosquito-borne diseases. But, by the late 1800s, mosquitoes had set up permanent housekeeping, setting the stage for epidemic transmission of avian malaria and pox. Honeycreepers – just like people faced with novel viruses such as swine flu – had no natural resistance against these diseases.

Before long, Hawaii’s native honeycreepers significantly declined in numbers and geographic range. It was likely that malaria swept rapidly across all of the lower Hawaiian Islands after the disease was introduced, leaving few survivors. Today, native Hawaiian birds face one of the highest rates of extinction in the world. Of 41 honeycreeper species and subspecies known since historic times, 17 are probably extinct, 14 are endangered, and only 3 are in decent shape.

Pox and malaria transmission in Hawaii depends on climatic conditions, especially seasonal changes in temperature and rainfall that increase or decrease mosquito populations. “Without question, the one factor that prevented widespread and rapid extinction of virtually all of Hawaii’s native honeycreepers after the introduction of avian pox and avian malaria was the presence of high-altitude disease refuges on Kauai, Maui and Hawaii,” said lead study author Dr. Carter Atkinson, a USGS microbiologist based at the USGS Pacific Islands Ecosystems Research Center in Hawaii.

These cool, high-elevation – above 4,000 feet (1,200 meters) — mountains not only provided habitats that mosquitoes didn’t thrive in, but they also had habitat that honeycreepers liked, wrote the authors. While birds in those areas find refuge from the diseases – dispersing juvenile birds and adults that follow seasonal flowering of native plants to lower elevations are exposed to disease.

“Unfortunately,” said study co-author, USGS scientist Dr. Dennis LaPointe, “this seasonal movement happens at the same time that mosquito populations soar at mid-elevations, which fuels high disease-transmission rates there. There’s a continuous source of disease-susceptible birds each fall.”

Although most disease transmission now occurs in these mid-elevation forests, this will change if the projected 3.6 degrees Fahrenheit (2 degrees Centigrade) raise in temperature occurs.

“With this kind of temperature change, about 60 to 96 percent of the high-elevation disease refuges would disappear,” said Atkinson. For example, available high-elevation forest habitat in the low-risk disease zone would likely decline by nearly 60 percent at Hanawi Natural Area Reserve on Maui to as much as 96 percent at Hakalau Forest National Wildlife Refuge on Hawaii Island. On other islands, such as Kauai, with lower elevations and no low-risk zones even now, predicted temperature changes would likely be catastrophic for remaining honeycreeper species.

“Right now, disease transmission in the mountains of Kaui is highly seasonal, but with temperature increases, disease would be able to be transmitted throughout most of the year,” said Atkinson. …

Honeycreepers rival Darwin’s finches in the Galapagos Islands in terms of their bill types and number of species that descended from a common founder. The birds specialize on food that includes nectar, fruits and insects. Before people came to the islands, as many as 56 kinds of honeycreepers probably occurred.

Avian malaria is caused by a protozoan parasite, and avian pox is a viral infection that typically causes tumor-like swellings on exposed skin of the feet, legs, beak and eyelids of infected birds. Malaria often results in appetite and weight loss, anemia, and massive enlargement of birds’ liver and spleen.

###

The article, Introduced avian diseases, climate change, and the future of Hawaiian honeycreepers, was published in the Journal of Avian Medicine and Surgery.

The Kaua`i Creeper or `Akikiki has been named one of America’s top ten threatened species impacted by global warming in a new report released today: here.

8 thoughts on “Climate change threatens Hawaiian honeycreepers

  1. Ten reasons why population control is not an answer to climate
    change

    By Simon Butler
    June 1, 2009 — Climate change is the greatest challenge humanity has
    ever faced. The scientific evidence of the scale of the threat is
    overwhelming, compelling and frightening. Climate tipping points —
    points which if crossed will lead to runaway global warming — are being
    crossed now. A discussion has surfaced about whether population-control
    measures should be a key plank in the climate action movement’s campaign
    arsenal. Below are 10 reasons why such a decision would hinder, rather
    than help, the necessary task of building a movement that can win.

    * Read more http://links.org.au/node/1076

    Like

  2. Extinct bird species’ fossils are found at Kalaeloa refuge

    By Darin Moriki

    POSTED: 01:30 a.m. HST, Jul 28, 2009

    U.S. Fish and Wildlife Service workers and scientists doing coastal habitat restoration work at Kalaeloa recently discovered fossilized remains, including those of several extinct bird species.

    “The discovery of these ancient bird bones, including several species now extinct and maybe even new species not known before, is a great reminder of the truly unique history and wonderful diversity of Hawaii’s birds,” said refuge manager David Ellis in a prepared statement.

    Both the Bishop Museum and the Smithsonian Institution are categorizing and preserving the bones. Although the age of the bones has yet to be pinpointed through the use of radiocarbon dating, scientists noted that bird fossils found at similar sites on the Ewa Plain date to about 1,000 to 8,000 years ago.

    The bird bones were discovered while scientists were restoring tidal pools that were once part of the former Barbers Point Naval Station, now the Pearl Harbor National Wildlife Refuge-Kalaeloa Unit.

    Scientists have found remains of an extinct hawk — the first reported as a fossil on Oahu — a long-legged owl, Hawaiian sea eagle, petrel, two species of crow, Hawaiian finches, Hawaiian honeyeaters and the moa nalo — a flightless gooselike duck.

    An unexpected discovery of rare avian fossil remains, believed to be thousands of years old, has scientists excited.

    “These fossils of extinct birds give us a glimpse of an earlier time on Oahu when the lowlands teemed with native birds, insects, and plants,” said Helen James, a research zoologist and curator of birds for the Smithsonian, in a written statement. “Lamentably, the birds cannot be brought back to life, but by studying their bones we at least gain an appreciation of Oahu’s rich natural heritage.”

    According to Sheila Conant, an associate zoology professor at the University of Hawaii, researchers can use fossil records “to tell us about what it was like before people got here, and what it was like over time as they arrived and as population increased.”

    “I’m always delighted when someone finds a new fossil, especially when it’s something interesting,” Conant said. “To know that we had a diversity of birds before people got here is exciting for me.”

    Leonard Freed, also an associate UH zoology professor, added that researchers can use information from the discovery to gain a better knowledge in what types of characteristics shaped their environment.

    “The fossil birds suggest that the characteristics may be shaped in an earlier environment,” Freed said. “At minimum the fossils show that the diversity of birds in Hawaii was much greater than what has been documented historically.”

    U.S. Fish and Wildlife Service workers and scientists doing coastal habitat restoration work at Kalaeloa recently discovered fossilized remains, including those of several extinct bird species.

    “The discovery of these ancient bird bones, including several species now extinct and maybe even new species not known before, is a great reminder of the truly unique history and wonderful diversity of Hawaii’s birds,” said refuge manager David Ellis in a prepared statement.

    Both the Bishop Museum and the Smithsonian Institution are categorizing and preserving the bones. Although the age of the bones has yet to be pinpointed through the use of radiocarbon dating, scientists noted that bird fossils found at similar sites on the Ewa Plain date to about 1,000 to 8,000 years ago.

    The bird bones were discovered while scientists were restoring tidal pools that were once part of the former Barbers Point Naval Station, now the Pearl Harbor National Wildlife Refuge-Kalaeloa Unit.

    Scientists have found remains of an extinct hawk — the first reported as a fossil on Oahu — a long-legged owl, Hawaiian sea eagle, petrel, two species of crow, Hawaiian finches, Hawaiian honeyeaters and the moa nalo — a flightless gooselike duck.

    An unexpected discovery of rare avian fossil remains, believed to be thousands of years old, has scientists excited.

    “These fossils of extinct birds give us a glimpse of an earlier time on Oahu when the lowlands teemed with native birds, insects, and plants,” said Helen James, a research zoologist and curator of birds for the Smithsonian, in a written statement. “Lamentably, the birds cannot be brought back to life, but by studying their bones we at least gain an appreciation of Oahu’s rich natural heritage.”

    According to Sheila Conant, an associate zoology professor at the University of Hawaii, researchers can use fossil records “to tell us about what it was like before people got here, and what it was like over time as they arrived and as population increased.”

    “I’m always delighted when someone finds a new fossil, especially when it’s something interesting,” Conant said. “To know that we had a diversity of birds before people got here is exciting for me.”

    Leonard Freed, also an associate UH zoology professor, added that researchers can use information from the discovery to gain a better knowledge in what types of characteristics shaped their environment.

    “The fossil birds suggest that the characteristics may be shaped in an earlier environment,” Freed said. “At minimum the fossils show that the diversity of birds in Hawaii was much greater than what has been documented historically.”

    http://www.starbulletin.com/news/20090728_extinct_bird_species_fossils_are_found_at_kalaeloa_refuge.html

    Like

  3. Hawaiian birds raised in San Diego released

    By Susan Shroder
    Union-Tribune Staff Writer

    8:25 p.m. October 13, 2009

    SAN DIEGO – Twelve native Hawaiian birds that were born and raised at the San Diego Zoo were released in a Kauai forest Tuesday, marking the 10th year of a successful effort to restore the elusive bird’s population.

    The dozen puaiohi, or small Kauai thrush, are on the federal list of endangered species.

    Fifteen years ago, it was determined that only about 200 puaiohi were left in the wild, said zoo spokesman Andrew Circo. These birds are found only on the island of Kauai, where they live in a high-elevation wilderness preserve.

    The dwindling population prompted a repopulation effort, and the zoo’s bird conservation center started receiving puaiohi eggs from the preserve in 1996. A total of 188 captive-bred puaiohi have been released into the Kauai forest during the past decade.

    The released birds are banded for identification and fitted for a radio transmitter that allows researchers to document their movement and survival.

    In addition to the zoo’s Institute for Conservation Research, partners in the program are the U.S. Fish and Wildlife Service, the U.S. Geological Survey, and the Hawaii Department of Land and Natural Resources.

    Susan Shroder: (619) 293-1876;

    http://www3.signonsandiego.com/stories/2009/oct/13/bn13birds20257/

    Like

  4. Pingback: Endangered Hawaiian honeycreepers, new study | Dear Kitty. Some blog

  5. Pingback: Birds and climate change | Dear Kitty. Some blog

  6. Pingback: Hawaiian bird conservation, new study | Dear Kitty. Some blog

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