Satellite tracking wild birds to study linkages between migratory birds and highly pathogenic avian influenza
After several years of planning, the Department of Microbiology of The University of Hong Kong (HKU), Asia Ecological Consultants (AEC), World Wide Fund For Nature Hong Kong (WWF),US Geological Survey (USGS), and the EMPRES-Wildlife Unit at the Food and Agriculture Organization of the United Nations (FAO), with support from the Agriculture, Fisheries and Conservation Department (AFCD) of the Hong Kong Special Administrative Region government, China, have recently launched a study in wild bird migration from Hong Kong.
Wild birds are often blamed to have spread avian influenza, but at present, little is known about their migratory routes and if they are connected to the spread of avian influenza. In an effort to better understand the role of migratory birds in the ecology and epidemiology of avian influenza, HKU, WWF and partners trapped, sampled, and marked 24 wild ducks with satellite transmitters on the December 10, 2008. Swab samples collected from these birds were tested for avian influenza viruses and Newcastle Disease at the HKU and found to be negative.
We anticipate that this project to satellite track movements of wild ducks will reveal more information about the linkages between the migration of wild birds and their involvement, if any, in the spread of avian influenza viruses. Past ringing studies have demonstrated that ducks from Hong Kong, specifically Northern Pintail and Eurasian Wigeon, migrate to northeastern China and the Russian Far East in the spring. However, little information exists about their migration routes, stop-over sites, timing, or final destination. Small satellite radios, attached to these ducks with backpacks, record and transmit GPS locations to provide detailed ecological information about their movements. Scientists will be able to determine whether bird locations coincide with outbreaks of Highly Pathogenic Avian Influenza (HPAI) H5N1 along their migration pathways.
The study is important to Hong Kong as the Inner Deep Bay wetland, which is listed as a wetland of international importance under the Ramsar Convention, provides both wintering and stop-over grounds to waterbirds migrating along the East Asian Australasian Flyway. Last year around 89,000 migratory and resident waterbirds were recorded during winter from the Deep Bay area and 20,000 shorebirds during the spring/autumn migration periods.
To date, over 30,000 samples from healthy wild birds collected by HKU from the Deep Bay area since 2003 have been tested negative for HPAI viruses, suggesting that the direct risk to humans from these species of healthy migratory wild birds is negligible. However, it should be noted that dead migratory or non-migratory wild birds found anywhere in Hong Kong should not be directly handled by the general public, and the AFCD should be contacted to investigate the cause of death and to properly dispose of carcasses.
The FAO and USGS have five other such projects throughout East Asia. Movements of the Hong Kong satellite tagged ducks can be viewed online by visiting the USGS website (
http://www.werc.usgs.gov/sattrack/hongkong/index.html ).
野鳥衛星追蹤有助研究禽流感之傳播
經過多年的策劃，香港大學微生物學系與亞洲生態環境顧問有限公司、世界自然基金會香港分會、US Geological Survey (USGS)，及聯合國糧食及農業組織之野生動物分隊在香港漁農自然護理署(漁護署)的協助下，最近進行一項研究野鳥遷徒路線的計劃。
由於野鳥一般被認為與禽流感病毒傳播有關，但現時對野鳥遷徒路線是否與禽流感病毒傳播有關所知甚少，為進一步了解候鳥在高致命禽流感病毒傳播方面所扮演的角色，香港大學微生物學系及伙伴於二零零八年十二月十日在二十四隻野鴨身上，進行環誌及抽取樣本化驗，並同時安裝衛星發訊器。這些從野鴨身上索取的樣本經禽流感及新城病毒測試，都呈陰性反應。
我們深信藉此計劃，可進一步了解野鳥的遷徒路線及野鳥是否與禽流感爆發之地區有所聯繫。在過去鳥類環誌研究中，我們發現在香港渡冬的野鴨（特別是針尾鴨及赤頸鴨），在春天會遷徒至中國東北部及俄羅斯東部。可惜的是，對於這些野鳥的遷徒路線、停歇點、遷徒及停留時間，以及最後目的地，我們只略知一二。透過這項計劃，安裝在野鴨背部的衛星發訊器可清晰地記錄及傳送全球衛星定位系統的位置，屆時我們便可得知這些野鴨遷徒活動的生態資訊。科學家及研究員亦可藉此透過衛星定位翻查路線是否與禽流感爆發的地區相近。
這項研究計劃對香港甚為重要，因為本港內后海灣濕地根據拉姆薩爾公約列為國際重要濕地，為東亞澳大拉西亞飛行航道的遷徒水鳥提供渡冬地及停歇點。去年冬季，后海灣濕地曾錄得逾八萬九千隻水鳥(包括候鳥和留鳥)渡冬。而在春秋二季遷徙期間，后海灣濕地亦是約二萬隻濱鳥休息及補充能量的加油站。
由二零零三年開始，香港大學於后海灣濕地共索取超過三萬個野鳥樣本，全部樣本對高致命禽流感H5N1呈陰性。這實驗結果顯示：人類從這些健康的野鳥身上直接感染禽流感的機會很低。但市民需要注意切勿接觸任何野鳥屍體，而應聯絡漁護署跟進及處理。
而聯合國糧食及農業組織與USGS亦同時於亞洲其他五個地方進行此計劃。閣下可於以下網頁瀏覽在香港裝置衛星發訊器的野鴨之遷徒路線: (
http://www.werc.usgs.gov/sattrack/hongkong/index.html ).
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Last edited by BWA at 30/01/2009 06:00 ]
