Apr. 14 was "the darkest day" in the history of protecting endangered Yangtze Finless Porpoises, according to Xu Yaping, president of the Finless Porpoise Protection Association in Yueyang City, central China's Hunan Province.

On that day, four porpoises were found dead, "one of which was even pregnant with a baby." From Mar. 3 to Apr. 15, twelve dead porpoises were discovered.

Currently, the Yangtze Finless Porpoise is a second class national-level protected animal. Figures from 2006 show there were 230 finless porpoises left in Dongting Lake. By 2007, that figure had reached 180, which sunk to 145 by January 2009 and 114 by January 2010.

By this March, scientists estimated there were only 85 finless porpoises left in the lake, 145 less than six years ago.

Xie Yongjun, associate professor of veterinary medicine in Yueyang Vocational Technical College, conducted a dissection for one of the dead porpoises retrieved from Dongting Lake on Apr. 9 and found no food residue in its digestive system.

And He Daming, a local fisherman, expressed his doubts that the porpoises had died only from starvation.

On Apr. 16, experts from the Institute of Hydrobiology of the Chinese Academy of Sciences were invited to perform autopsies on two more dead porpoises. They announced the death reasons two days later: one was wounded to death by propellers, while the other suffered a sudden death due to electrofishing or other man-made causes.

Sand excavation, huge profits and alarming extinction rate

Pointing at the continuous flow of ships transporting sand, He Daming gave a look of disapproval. From Dongting Lake, most of the loaded dredges make their way to Nanjing or Shanghai by way of Wuhan.

The busy shipping activities, such as transporting sand, block the porpoise's migration channel between Dongting Lake and the Yangtze River and prevent gene exchange, said Jiang Yong, the Changsha program director of the World Wide Fund for Nature. Besides, as sand excavation destroys the lake bed, its existing hydrological condition has changed, threatening the natural supply of fish the mammals feed on.

"Even the fish cannot survive. How can finless porpoises not become extinct?" Jiang said.

According to Jiang, these sand dredges with huge power make a lot of noise, which could disturb the sonar ability of finless porpoises and increase the difficulty for them to find food.

Peng Xianglin is the boss of a local company in Yueyang. In his eyes, those who can get approval for sand excavation on Dongting Lake "are never ordinary people." "Behind a sand dredge there is a multimillionaire," he said.

According to Peng, who is also president of the Association for Wetland Conservation in Yueyang, one 1,000-horsepower sand dredge can generate yearly profits of up to 10 million yuan (US$1.57 million). Therefore, sand excavation has proven to be an important source of financial income for the local governments of Yueyang County and Miluo City, where Dongting Lake is located.

In 2005, a local company won the right of sand excavation on east Dongting Lake for five years for a price of 51.28 million yuan. The Yueyang county government requires that the number of its sand dredges should not exceed six and the total power used should not exceed 13,000 horsepower.

However, according to a report by Huang Jianwen, a CPPCC member of Yueyang County, from July 2006 to May 2010, the company actually sent 16 sand dredges every day, with the total power of 66,800 horsepower, five times higher than the contract stipulates.

Then in 2010, the Yueyang county government ended the contract with this company and launched a new bid with a minimum price of 100 million yuan.

This year, due to the multiple deaths of finless porpoises, the Yueyang Water Conservancy Bureau issued a notice on April 23 that all sand excavation activities on east Dongting Lake should be suspended for seven-day inspection. The total number of sand dredges in this area should not exceed 20. Their total power should not surpass 55,000 horsepower, with no more than 2,400 horsepower each.

在湖南省岳陽市江豚協會會長徐亞平看來，4月14日堪稱江豚保護史上“最黑暗的一天”。

當天有4條江豚死去，“還有一頭江豚肚子里正懷著胎兒。”從3月3日到4月15日，共有12具江豚尸體被發現。

目前，長江江豚是國家二級保護動物。統計數據顯示，2006年，洞庭湖江豚數量為230頭；2007年，江豚數量為180頭；2009年，江豚數量為145頭；2010年，江豚數量為114頭。

到了今年3月，水生所的專家測算到的江豚只有85頭。近6年內，洞庭湖已累計減少了145頭江豚。

4月9日，岳陽職業技術學院獸醫學副教授謝擁軍對洞庭湖打撈出來的一具江豚尸體進行了解剖，發現其胃部沒有任何食物殘留。

“江豚是餓死的嗎？”當地漁民何大明發出了疑問。

4月16日，中科院水生所的專家又對兩具江豚尸體進行了解剖。兩天后，水生所發布消息說，一頭江豚是遭螺旋槳擊傷致死，另一頭則疑為電捕魚或其他原因導致猝死。

暴利采砂瘋狂，江豚瀕臨滅絕

手指著湖面上川流不息的運沙船，何大明神色凝重。它們載滿沙子，目的地大多經由武漢，長途跋涉到南京、上海。

據世界自然基金會長沙項目辦主任蔣勇介紹，繁忙的運砂等航運活動阻塞了江豚在洞庭湖與長江之間遷徙通道，妨礙了基因交流。同時，采砂作業掏空了洞庭湖湖床，改變了既有水文狀況，對魚類資源的繁殖、生存形成挑戰。

“魚都活不下來，江豚能不滅亡嗎？”蔣勇說。

他表示，采砂船的馬力巨大，產生的噪聲擾亂江豚的聲納定位，使其捕食困難。

彭祥林是岳陽當地的一公司老板，在他眼里能在岳陽洞庭湖水域審批到采砂權的，“那都不是一般人。”“一艘采砂船背后就是一個千萬富翁。”他這么說道。

彭祥林還是岳陽市濕地環保促進會的會長，據他介紹，一條1000馬力的采砂船，一年的利潤可達千萬元上下。由此，出讓砂石資源就成了洞庭湖所在的岳陽縣、汨羅市的重要財政收入來源。

2005年，岳陽當地一家公司曾以5128萬元的價格取得東洞庭湖5年的砂石開采權。其時，岳陽縣規定采砂船數量只能是6條，總功率為1.3萬馬力。

但據時任岳陽縣政協委員黃建文的提案顯示，自2006年7月至2010年5月，該公司每日采挖船的功率達到6.68萬馬力，超過合同規定5倍，采砂船達到16條。

到了2010年，岳陽縣終止與該公司的開采合同，遂以1億元的底價重新招標。

今年，由于發生了多起江豚死亡事件，岳陽市水務局曾在4月23日專門下發通知，要求在東洞庭湖暫停所有砂石開采工作，開展7天的專項督查，要求在東洞庭湖區域控制企業船數在20艘以內、總功率不超過55000馬力、單船功率不超過2400馬力。