Page 29 - OPCF 2020

在首十個月的研究中，研究團隊調查了長達二千九百 七十七點七公里範圍，發現了一百四十九個中華白海 豚群組，並成功拍攝和辨認超過一千三百條個體。令 人意外的是，研究團隊在過程中發現區內的捕魚活動 並不活躍，這很可能與當地魚量經過數十年濫捕早已 變得匱乏有關，亦足證人類過度開發，會對人類與動 物的重要食物資源造成長久破壞。
研究團隊亦對海上交通帶來的影響進行量化研究，在 二零一六至二零一八年期間，研究區域內一共錄得 一億七千五百萬次船航活動。雖然量化研究活動在 二零二零年初，一度因二零一九冠狀病毒病疫情而中 斷，但種群的相片辨認調查仍然持續，並進展良好。 研究團隊預期將於二零二零年六月，整合目前所得資 料並發表報告，為伶仃洋海域中華白海豚及當地海洋 保育狀況提供更新資訊。
研究項目二: 引入長航時無人機開拓嶄新研究方法 科技能夠為保育帶來突破，亦有助研究人員更精準地 研究中華白海豚。有見及此，保育基金特別資助一項 中華白海豚影像自動識別系統研究，期望透過由自主 設計的長航時無人機拍攝影像，獲得可靠定位數據。 研究團隊在二零一九年十月至二零二零年一月期間， 於廣西大風江口合共進行三次巡航與影像拍攝任務， 成功拍攝逾四千張圖片。早期測試發現，系統透過 圖片識別中華白海豚並判斷其數量，準確度達百分之 三十。目前研究團隊正致力改良系統的精準表現，並 會研究減低水上交通與天氣因素對巡航拍攝造成的影 響，期望在疫情過後重新展開測試。
陳釗賢博士
• 二零一九至二零二零年度 首席研究員
• 鯨豚生態研究所研究員
Dr. Stephen C.Y. Chan
• 2019/20 Project Principal Investigator
• Research Scientist,
The project has surveyed a total of 2,977.7 km, sighting 149 groups of dolphins consisting of over 1,300 individuals successfully photographed and identified during the first 10 months of the project. Throughout the survey, the study team observed surprisingly low fishing activity within the region, most likely due to severely degraded fish stocks over the past decades. This illustrates how human overexploitation deprives both people and animals of vital food sources in the long-term.
The influence of marine traffic was also quantitated, with data revealing that over 175 million vessels have passed through or nearby the study area during 2016-2018. In spite of disruption in early 2020 due to COVID-19, ongoing photo identification of the population has been going well. The data gathered so far is expected to be filed in June 2020, which will offer a clear update on the status of Lingding Bay’s dolphins and local ocean conservation.
Project 2:
Exploration of New Research Technology and Methods Using Long-duration Drone
Recent technology has created opportunities to sharpen and improve insights into Chinese white dolphin conservation. OPCFHK has funded the development of a visualisation system that automatically recognises Chinese white dolphins and obtains coordinate information from images captured by self-designed, long-duration drones. From October 2019 to January 2020, the team conducted three filming cruises around the Dafeng River Estuary in Guangxi capturing over 4,000 images. Early iterations show that the system is able to detect and count Chinese white dolphins from images with 30% confidence. Efforts are underway to improve its accuracy while mitigating the effects of river traffic and weather conditions in preparation for further filming after the pandemic.
中華白海豚是香港及珠江三角洲區海洋保育狀況的標誌性物種。可惜的是，由於沿岸地 區的種種人為因素，牠們亦是世上最受影響的海豚種群。保育基金多年來資助不同的研 究項目，幫助我們加深對這種海豚的認識，並為未來推行的保育工作提供科學實證基 礎。作為受助者，我十分感謝保育基金為年輕本地研究員及學生提供野生動物保育的研 究資助。
Chinese white dolphins are one of the iconic species of marine conservation in Hong Kong and the Pearl River Delta. However, they are also among the world’s most impacted dolphin populations under a multitude of coastal anthropogenic pressures. Over the years, OPCFHK has funded research projects which help advance our knowledge of these dolphins and establishes an evidence-based foundation for effective conservation. As a grant recipient I am also appreciative of OPCFHK’s funding support for young
©LIN Wenzhi
©CHEN Mo
Cetacea Research Institute
,
local researchers and students in wildlife conservation.
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