The Native Forest Birds of Guam

1983 ◽  
pp. ii-61 ◽  
Author(s):  
J. Mark Jenkins
Keyword(s):  
The Condor ◽  
2005 ◽  
Vol 107 (3) ◽  
pp. 537-546 ◽  
Author(s):  
Carter T. Atkinson ◽  
Julie K. Lease ◽  
Robert J. Dusek ◽  
Michael D. Samuel

AbstractIntroduced avian pox virus and malaria have had devastating impacts on native Hawaiian forest birds, yet little has been published about their prevalence and distribution in forest bird communities outside of windward Hawaii Island. We surveyed native and non-native forest birds for these two diseases at three different elevations on leeward Mauna Loa Volcano at the Kona Forest Unit of Hakalau Forest National Wildlife Refuge. Prevalence of malaria by both serology and microscopy varied by elevation and ranged from 28% at 710 m to 13% at 1830 m. Prevalence of pox-like lesions also varied by altitude, ranging in native species from 10% at 710 m to 2% at 1830 m. Native species at all elevations had the highest prevalence of malarial antibody and pox-like lesions. By contrast, pox-like lesions were not detected in individuals of four non-native species and only 5% of Japanese White-eye (Zosterops japonicus) was positive for malaria. A significantly high proportion of birds with pox-like lesions also had serological evidence of concurrent, chronic malarial infections, suggesting an interaction between these diseases, dual transmission of both diseases by the primary mosquito vector (Culex quinquefasciatus) or complete recovery of some pox-infected birds without loss of toes. Results from this study document high prevalence of malaria and pox at this refuge. Development of effective disease control strategies will be important for restoration of remnant populations of the endangered ‘Akiapola‘au (Hemignathus munroi), Hawaii Creeper (Oreomystis mana), and Hawaii ‘Akepa (Loxops coccineus coccineus) that still occur on the refuge.Prevalencia de Lesiones del Tipo de la Viruela Aviar y Malaria en Comunidades de Aves de Bosque en el Volcán Leeward Mauna Loa, HawaiResumen. La malaria y la viruela aviar, ambas introducidas, han tenido un impacto devastador sobre las aves nativas de bosque, pero se ha publicado poco sobre su prevalencia y distribución en las comunidades fuera de la isla de Hawai. Muestreamos aves de bosque nativas y no nativas para determinar la presencia de estas dos enfermedades a diferentes elevaciones en el volcán Mauna Loa en la Unidad Forestal de Kona del Refugio de Fauna Silvestre del Bosque Nacional de Hakalau. La prevalencia de malaria determinada a través de serología y microscopía varió con la altitud entre un 28% a 710 m y un 13% a 1830 m. La prevalencia de lesiones del tipo de la viruela aviar también varió con la altitud, entre un 10% a 710 m y un 2% a 1839 m en especies nativas. Las especies nativas tuvieron la más alta prevalencia de anticuerpos contra malaria y lesiones del tipo de la viruela aviar. De modo contrastante, las lesiones del tipo de la viruela aviar no se detectaron en individuos de cuatro especies no nativas y sólo el 5% de los individuos de la especie Zosterops japonicus fue positivo para malaria. Una proporción significativamente alta de las aves con lesiones del tipo de la viruela aviar también presentaron evidencia serológica de infecciones crónicas de malaria simultáneas, sugiriendo una interacción entre estas dos enfermedades, transmisión dual de las enfermedades por el vector principal (el mosquito Culex quinquefasciatus) o recuperación completa en algunas aves infectadas con viruela aviar sin la pérdida de dedos. Los resultados de este estudio documentan altas prevalencias de malaria y viruela aviar en este refugio. El desarrollo de estrategias de control de estas enfermedades será importante para la restauración de las poblaciones remanentes de las especies en peligro Hemignathus munroi, Oreomystis mana, y Loxops coccineus coccineus que aún existen en el refugio.


The Auk ◽  
2002 ◽  
Vol 119 (4) ◽  
pp. 929-942 ◽  
Author(s):  
Charles van Riper ◽  
Sandra G. van Riper ◽  
Wallace R. Hansen

Abstract We determined prevalence and altitudinal distribution of forest birds infected with avian pox at 16 locations on Hawaii, from sea level to tree line in mesic and xeric habitats, during 1977–1980. Isolates from lesions were cultured in the laboratory for positive identification of Poxvirus avium. Infected birds from the wild were brought into the laboratory to assess differences in the course of infection in native versus introduced species. We also documented distributions and activity cycles of potential avian pox vectors.>Native forest birds were (1) more susceptible to avian pox infection than were introduced species, (2) most likely to be infected during the wet season, and (3) found to have a higher prevalence in mesic when compared to xeric forests. Avian pox occurred in forest birds at all elevations, but highest levels were in the mid-elevational ranges (∼1,200 m) where vectors and native birds had the greatest overlap. Temporal and elevational differences in prevalence were apparent throughout the annual cycle. Avian pox probably did not reach epizootic proportions on Hawaii until after introduction of the mosquito and domestic birds in the early 1800s, and since then has had a negative effect on the population dynamics of native forest birds. Today, this introduced disease is an important factor that should be considered in future conservation efforts that are directed at the recovery of native forest birds in Hawaii.


The Auk ◽  
1985 ◽  
Vol 102 (1) ◽  
pp. 229-231
Author(s):  
Jared M. Diamond
Keyword(s):  

2010 ◽  
Vol 16 (3) ◽  
pp. 181 ◽  
Author(s):  
Katherine Tucker-Mohl ◽  
Patrick Hart ◽  
Carter T. Atkinson

Hawaii?s native birds have become increasingly threatened over the past century. Introduced mosquito borne diseases such as avian malaria may be responsible for the near absence of endemic Hawaiian forest birds in low-elevation habitats. The recent recognition that some native Hawaiian forest birds may be repopulating moist lowland habitats as a result of evolved resistance to this disease has increased the conservation value of these areas. Here, we investigate whether remnant low elevation dry forests on Hawaii Island provide natural ?refuges? from mosquito-transmitted malaria by nature of their low rainfall and absence of suitable natural sources of water for mosquito breeding. Unlike lowland wet forests where high rates of disease transmission may be selecting for disease resistance, lowland dry forests may provide some refuge for native forest birds without natural resistance to malaria. We mistnetted forest birds in two lowland dry forests and tested all native birds by microscopy and serology for avian malaria caused by the Plasmodium relictum parasite. We also conducted surveys for standing water and mosquito larvae. Overall prevalence of infections with Plasmodium relictum in the Hawaii Amakihi Hemignathus virens virens was 15%. Most infected birds had lowlevel parasitemias, suggesting chronic infections. Although avian malaria is present in these lowland dry forest Amakihi populations, infection rates are significantly lower than in wet forest populations at similar elevations. Sources of breeding mosquitoes in these forests appeared to be largely anthropogenic; thus, there is potential to manage dry forests as mosquito-free habitat for Hawaii Amakihi and other Hawaiian forest birds.


NeoBiota ◽  
2019 ◽  
Vol 49 ◽  
pp. 1-17 ◽  
Author(s):  
Amy A. Yackel Adams ◽  
Melia G. Nafus ◽  
Page E. Klug ◽  
Björn Lardner ◽  
M. J. Mazurek ◽  
...  

Invasive predators are responsible for almost 60% of all vertebrate extinctions worldwide with the most vulnerable faunas occurring on islands. The brown treesnake (Boigairregularis) is a notorious invasive predator that caused the extirpation or extinction of most native forest birds on Guam. The success of avian reintroduction efforts on Guam will depend on whether snake-control techniques sufficiently reduce contact rates between brown treesnakes and reintroduced birds. Mouse-lure traps can successfully reduce brown treesnake populations at local scales. Over a 22-week period both with and without active snake removal, we evaluated snake-trap contact rates for mouse- and bird-lure traps. Bird-lure traps served as a proxy for reintroduced nesting birds. Overall, mouse-lure traps caught more snakes per trap night than did bird-lure traps. However, cameras revealed that bird-lure traps had a snake contact rate almost 15 times greater than the number of successfully captured snakes. Snakes that entered bird-lure traps tended to be larger and in better body condition and were mostly captured in bird-lure traps, despite numerous adjacent mouse-lure traps. Traps placed along grid edges caught more snakes than interior traps, suggesting continuous immigration into the trapping grid within which bird-lure traps were located. Contact between snakes and bird-lure traps was equivalent before and after snake removal, suggesting mouse-lure traps did not adequately reduce the density of snakes that posed a risk to birds, at least at the timescale of this project. This study provides evidence that some snakes exhibit prey selectivity for live birds over live mouse lures. Reliance on a single control tool and lure may be inadequate for support of avian reintroductions and could lead to unintended harvest-driven trait changes of this invasive predator.


EDIS ◽  
2017 ◽  
Vol 2017 (6) ◽  
Author(s):  
Mark E. Hostetler ◽  
Jan-Michael Archer

N/A


Fact Sheet ◽  
2005 ◽  
Author(s):  
Bethany L. Woodworth ◽  
Carter T. Atkinson ◽  
Michael D. Samuel ◽  
Dennis A. LaPointe ◽  
Paul C. Banko ◽  
...  

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