第58屆Intel ISEF中國參賽項目：中國長江中幼年江豚的脆弱性
華中師范大學第一附屬中學 高二 張萬祎
學科：動物學
珍稀物種長江江豚的新生幼體死亡率明顯高于其他年齡段。本研究的目的在于尋找該現(xiàn)象的內(nèi)在原因和外部因素，為制定保護對策提供科學依據(jù)。本項目利用肉眼、照相機、攝像機、高頻錄音機等手段觀察記錄了2頭新生幼豚的社群行為和回聲定位能力發(fā)育過程。采用船舶噪聲回放試驗，探討了噪聲對幼豚行為的干擾。觀察發(fā)現(xiàn)，幼豚出生后約一個月內(nèi)對母豚的依賴十分強烈，幼豚母子聯(lián)系密切，表現(xiàn)在母子距離近，母子對視頻繁。出生后至第21天，未觀察到幼豚探測行為，27天前未記錄到幼豚發(fā)出的回聲定位信號。噪聲回放試驗發(fā)現(xiàn)，船舶噪聲對幼豚行為干擾明顯，破壞母子豚聯(lián)系。本研究得出兩點主要結(jié)論，一是發(fā)現(xiàn)江豚發(fā)育過程中的一個缺陷，即幼豚出生后的頭一個月為極為脆弱期，江豚在此期間對母豚的依賴性強，不具回聲定位能力，對環(huán)境探測和適應(yīng)能力差是江豚幼齡死亡率高的內(nèi)在原因。二是通過實驗證明船舶噪聲在此脆弱期極有可能破壞母子聯(lián)系，這是導(dǎo)致其死亡率高的外在因素。建議制定江豚保護對策時，應(yīng)優(yōu)先考慮江豚繁殖期幼豚母子聯(lián)系的維持。
Vulnerability of Newborn Freshwater Porpoise in China's Yangtze River
Animal Science
Zhang Wanyi 17, No.1 Middle School Attached to Central China Normal University
Yangtze finless porpoise, Neophocaena phocaenoides asiaeorientialis, is a unique, endangered freshwater cetacean species in the Yangtze River in China. Mortality of newborns of the porpoise is obviously higher than other ontogenetic stages. Aims of this study are to find out interior reasons and exterior factors that cause the problem, with which, more effective conservation strategies are going to be drawn.
Process of ontogeny of social behavior and echolocation in two newborn calves in captivity was observed and analyzed by means of direct observation and using digital camera, video camera, high frequency sound recorder, etc. By the experiment of ship noise play back, influence on social behavior of the newborns by ship noise was tested.
It was found that the newborn was deeply relied on the mother and closely tied with the mother during the first month. It could be demonstrated that the mother-calf distance was always rather close and the mother-calf eye contact appeared quite often when swimming and surfacing. No exploring behavior was found till the 21st day and no echolocation signal was recorded till the 27th day. Its behavior was strongly influenced by the ship noise, which could possibly break down the mother-calf link.
Two conclusions were drawn through this project. One was the discovery of a bug during the ontogeny of social behavior and echolocation, namely, the first month of newborn calf is a very vulnerable period. The calf totally relies on the link with the mother since its poor ability of exploring and adaptability, and no echolocation produced in this period. It is the interior reason of the high mortality. The other was that it has been proved that the mother-calf link in the vulnerable period could be broken down by the man-made ship noise, which becomes the exterior cause of the problem. Based upon the conclusions, it is recommended that prior strategy could be to prevent the mother-calf link from broken in the early stage of the breeding season.
