Navigation Links
Native forest birds in unprecedented trouble, according to University of Hawaii at Manoa researchers
Date:1/19/2012

Native birds at Hakalau Forest National Wildlife Refuge are in unprecedented trouble, according to a paper recently published in the journal PLoS ONE. The paper, titled "Changes in timing, duration, and symmetry of molt of Hawaiian forest birds," was authored by University of Hawai'i at Mānoa Zoology Professor Leonard Freed and Cell and Molecular Biology Professor Rebecca Cann.

In the paper, Freed and Cann report that birds are now so food-deprived that they take up to twice as long replace their feathers, an annual process known as molt. The authors confirmed the hypothesis that Japanese white-eye (Zosterops japonicus) birds are effectively competing with most species of native birds. Their research found that both young and adult birds took longer to complete their molt. Young birds normally complete their juvenile molt in five months, beginning before June and ending in October. Now it is taking the birds as late as March of the following year to finish that molt. Adults are also taking that much longer to replace their feathers. Freed and Cann propose that this change in molt matches those in studies that experimentally starve birds.

In addition, the authors report that more adults are beginning their molt early, during months when they normally breed. Some molting females even had active brood patches. Birds generally avoid this overlap in their life history because both activities require extra energy. In their study, Freed and Cann have identified that the endangered Hawai'i creeper had the greatest molting changes. The record change for an individual bird, a Hawai'i amakihi, was set by an individual that finished its juvenile molt from the previous year in March only to begin its adult molt in May. All Hawaiian honeycreepers had significant changes.

Usually birds molt the same primary flight feathers on the two wings at the same time to maintain maneuverability. However, by 2002, all species had asymmetric molt of these feathers. This is the first time asymmetric molt has been documented throughout a community of birds. This molt was experimentally seen previously in food-limited birds. In laboratory situations, starvation of birds to 60% of normal diet leads to the changes in molt that Freed and Cann observed in nature. Native birds died at a greater rate during the months of extended molt during 2000-2004, and survival worsened each year. A control set of years in the 1990's, with fewer white-eyes, showed no trend in survival.

The authors reported that the changes in molt were associated in every detail with the increase in Japanese white-eye birds, a bird intentionally introduced to Hawai'i in 1929 to control insects. According to Freed and Cann, the molt study complements a previous 2009 Current Biology paper by the authors showing that all species of native birds have stunted growth and lower survival. The authors suggest that no section of the refuge is safe from the competitive effects of this introduced bird, especially the lower closed forest section of the refuge which had the greatest non-normal molt in 2006.


'/>"/>

Contact: Leonard Freed
lfreed@hawaii.edu
808-956-8655
University of Hawaii at Manoa
Source:Eurekalert

Related biology news :

1. Findings prove Miscanthus x giganteus has great potential as an alternative energy source
2. Growstones ideal alternative to perlite, parboiled rice hulls
3. Cheap beads offer alternative solar-heating storage
4. Interethnic marriage between African- and Native-Americans produced many children
5. Targeted antibacterial proteins may offer antibiotic alternative
6. Coneheads (Protura) of Italy: What we know in their native country after a century
7. JBEI identify new advanced biofuel as an alternative to diesel fuel
8. Climate change could drive native fish out of Wisconsin waters
9. Warming climate could give exotic grasses edge over natives
10. 96-million-year-old fossil suggests prehistoric crocodile Terminonaris was Texas native
11. Behavioral treatment for migraines a cost-effective alternative to meds, study finds
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/2/2016)... June 2, 2016 The Department of ... awarded the 44 million US Dollar project, for the ... Plates including Personalization, Enrolment, and IT Infrastructure , ... the production and implementation of Identity Management Solutions. Numerous renowned ... Decatur was selected for the most ...
(Date:6/1/2016)... NEW YORK , June 1, 2016 ... Biometric Technology in Election Administration and Criminal Identification to ... According to a recently released TechSci Research report, " ... Sector, By Region, Competition Forecast and Opportunities, 2011 - ... $ 24.8 billion by 2021, on account of growing ...
(Date:5/16/2016)... NEW YORK , May 16, 2016   ... authentication solutions, today announced the opening of an IoT ... to strengthen and expand the development of embedded ... provides an unprecedented level of convenience and security with ... to authenticate one,s identity aside from DNA. EyeLock,s platform ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... ... June 24, 2016 , ... While the majority of commercial spectrophotometers and ... and the 6000i models are higher end machines that use the more unconventional z-dimension ... light beam from the bottom of the cuvette holder. , FireflySci has developed ...
(Date:6/23/2016)... , ... June 23, 2016 , ... ... release of its second eBook, “Clinical Trials Patient Recruitment and Retention Tips.” Partnering ... retention in this eBook by providing practical tips, tools, and strategies for clinical ...
(Date:6/23/2016)... 23, 2016   Boston Biomedical , an ... designed to target cancer stemness pathways, announced that ... Orphan Drug Designation from the U.S. Food and ... cancer, including gastroesophageal junction (GEJ) cancer. Napabucasin is ... inhibit cancer stemness pathways by targeting STAT3, and ...
(Date:6/23/2016)... -- A person commits a crime, and the detective uses ... criminal down. An outbreak of foodborne illness makes ... uses DNA evidence to track down the bacteria that caused ... not. The FDA has increasingly used a complex, cutting-edge technology ... Put as simply as possible, whole genome sequencing is a ...
Breaking Biology Technology: