NCKU Cetacean Research Center restores Taiwan’s first blue whale specimen
成大鯨豚中心全力復原製作台灣首件藍鯨標本
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          NCKU Marine Biology and Cetacean Research Center is now cleaning and preserving the skeleton of the world’s largest whale. The blue whale expired some time ago and drifted in the ocean. It was stranded on a beach in Taitung in January, 2020. After being transported back to NCKU, the skull was found to be severely damaged and shattered. This blue whale is a juvenile whale, which has more cartilage and is not easy to preserve. It is a difficult project to create a full skeleton specimen. Wang Hao-Wen, director of NCKU Marine Biology and Cetacean Research Center, said that the team will pull out all stops to complete the first blue whale specimen in Taiwan.

          The first blue whale stranded in Taiwan

          "In the past, there are no records of sightings or strandings of blue whales in Taiwan. According to the data, there were 14 records of capture around the Taiwan area during the 1920-1938 period, but there is no exact record of a capture location.", said Wang Hao-Wen, director of the NCKU Marine Biology and Cetacean Research Center. For decades, no blue whale has been recorded in the Taiwan region. According to the "Taiwan's Whale and Dolphin legend" provided by the Forestry Bureau, Council of Agriculture, Executive Yuan, there are nearly 30 observed species from the smaller dolphins to the larger sperm whale, of which there are no blue whales. In addition to understanding the cause of death, the blue whale stranding event has a great significance for the research of blue whales around the world if the bones can be properly preserved.

          In the face of climate change, marine conservation issues have received greater attention. The International Union for Conservation of Nature (IUCN) has included blue whales in the "IUCN Red List of Threatened Species." Scientists estimate that between 5,000 and 15,000 exist now. The events of illegal fishing or stranding incidents have always attracted great attention from animal protection groups and academia.

          Wang Hao-Wen pointed out that according to the necropsy evidence, the blue whale was no more than three years old. According to the literature, the blue whale is 7 meters long at birth, and can reach 15 meters in length in approximately 7-months, and achieve a maximum length of 30 meters. The life span of the blue whale is estimated to be 80 to 90 years , and some experts believe the blue whale can reach 110 years!

          Difficult task for blue whale research

          The NCKU Marine Biology and Cetacean Research Center is located in the southwest corner of the NCKU Annan Campus. The room is filled with whale bones that have been processed for many years. Wang Hao-Wen, professor Wang Jian-Ping NCKU student volunteers, veterinary departments from various universities, and volunteers transported and dissected the blue whale successfully.

          Wang Hao-Wen emphasized that this is the first record of blue whale stranded in Taiwan in nearly a century. At present, there are not many countries displaying blue whale solid bone specimens, as far as he knows, there are only Canada, the United States and the United Kingdom have displayed. If this blue whale will be exhibited in the future, NCKU will be the first place in Taiwan to display blue whale specimens.

          Talking about the process of processing the blue whale, Wang Hao-Wen said, "This whale has been hungry for too long." He said; “All the internal organs have decayed, and the muscles have degenerated into blood-like substance.” Although he tried to find food from the remains of the esophagus, stomach and intestine, he found no trace of food. The subcutaneous fat layer was very thin, so it is reasonable to infer that the whale had not eaten for a long period of time.

           

          Wang Hao-Wen pointed out that climate change and global warming can contribute to the cause of death, and by analyzing the carcass we can ascertain how the individual died. A few days ago, he went to Mai-Liao(麥寮)Port to process a dead False killer whale (Pseudorca crassidens). is the death was probably related to aging, because the teeth were ground flat and the fat layer was thin. It can be presumed that the body was in a weakened state and had no predation ability.

          Drift gill net entrapped bottlenose dolphin (Tursiops truncatus)

          Wang Hao-Wen's testimony of an example of a bottlenose dolphin ,who went to the Zhang-Bin Industrial Zone(彰濱工業區) recently. "It was entangled in the gill net. Is the death related to the entanglement of the gill net? It is necessary to prove this and then find out the reason. The dolphin is estimated to have died more than three weeks ago, and much of the evidence has disappeared. The stomach was found empty during the dissection, which means there has been no food intake for a long time period before death, and the subcutaneous fat layer was relatively thin. In general, dolphins entangled in fishing nets cannot break free could drown. However, this dolphin does not have this situation. It is necessary to further analyze.”

          Wang Hao-Wen said, "It was sad to find that blue whale mouth was entangled with fishing nets. The blue whale food intake method is to open their mouth and inhale copious amounts of seawater, then the mouth is closed and then the abdomen elastically retracts to squeeze out the seawater. The baleen plates will filter out small fish and shrimp for consumption. If the mouth can’t be opened properly, it will inhibit eating. "According to the information collected now, I know that the fishing net was the cause of death. This net is a type of fishing gear used by common fishing methods. The world has begun to reflect on this situation and recommend more ‘whale’ friendly fishing gear and greater fishing conservation behavior. The 14th goal of the United Nations Sustainable Development Goal mentions the importance of Marine protection. We should work hard to restore and understand the circumstances of the blue whale death, and discover things from this evidence, and remind humanity of the serious consequences.

          成功大學海洋生物暨鯨豚研究中心現正進行台灣有紀錄以來首見、全世界最大型生物藍鯨的骨架清洗與去腐保存工作。這隻藍鯨死亡多時,隨海洋漂流,2020年1月擱淺在台東海灘。經運回成大解剖後發現頭骨粉碎嚴重,而且該藍鯨屬於少年鯨,軟骨較多、不易保存,要製作全骨架標本是一件浩大工程。成大鯨豚中心主任王浩文表示,團隊將全力以赴,務必完成台灣第一個藍鯨標本。

          第一隻藍鯨死亡擱淺台灣

          「過去台灣並無藍鯨被目擊或擱淺的記錄,雖然日本統治台灣時期,南部有捕鯨船進出,根據資料記載1920-1938年期間,台灣周圍海域有14頭被捕獲的紀錄,但並沒有確切地記載捕獲地點。」成大鯨豚中心主任王浩文說,幾十年來,藍鯨都沒有在台灣周遭出現 的記錄。據行政院農委會林務局提供「臺灣的鯨豚」圖例,從體型最小的海豚、大至抹香鯨,多達近30種,其中沒有藍鯨。這次藍鯨擱淺事件,除了解死亡原因外,若能妥善保存全身骨頭,並製作成標本,對全世界藍鯨的研究具有重大意義。

          面對氣候變遷,海洋生態保育議題也備受關注,國際自然保護聯盟(IUCN) 已將藍鯨列入「瀕危物種紅皮書」,科學家估計現存約5千隻至1萬5千隻之間,每發現違法捕撈或海灘擱淺事件,總引起動保團體與學界高度重視。

          王浩文指出,依照解剖後所有的證據推論,該藍鯨不超過三歲。依已知的資料,藍鯨出生時身長就有7公尺,約7個月時身長可達15公尺,最大能達30公尺,學界研究藍鯨壽命最少有80-90歲,也有專家研究指出其壽命可達到110歲。

          藍鯨實體研究任務艱困

          成大鯨豚中心位於成大安南校區西南一隅,室內擺滿多年來處理的鯨骨,就連長達十多公尺的抹香鯨標本都以緊縮椎間盤方式存放著 。王浩文與退而不休的王建平教授有師生情緣,幸而有王建平老師全力支援,加上成大學生及多所大學的獸醫系與各界志工協助,讓這次台灣百年罕見的藍鯨運送、解剖順利完成,並將進一步分析研究死因,以及嘗試建置標本。

          王浩文強調,這是台灣近百年第一次有藍鯨擱淺的記錄,現在世界各國都想要有一隻真的藍鯨骨頭標本,目前展示藍鯨實體骨頭標本的國家不多,就他所知的有加拿大、美國、英國。如果這隻藍鯨未來展出,成大將是台灣第一個展示藍鯨標本的地方。目前師徒仍持續合作,為此重責大任而努力。

          談及處理藍鯨過程,王浩文感慨「這隻鯨實在餓太久了。」他說:體內所有內臟都爛掉,肌肉也都化成血水,雖嘗試從食道、胃和腸道的殘骸找食物的痕跡,但都找不到任何食物的殘留;而且皮下脂肪層很薄,因此合理推論牠應該有很長時間無法進食。

          許多民眾及政府官員會好奇詢問,為何鯨魚死了還要處理?王浩文指出,氣候變遷及全球暖化問題,其實可以從死亡的個體找出死亡原因,去分析 每隻鯨豚為什麼死亡,前幾天他到麥寮港口處理一隻已死的偽虎鯨,很可能就與老化有關,因為牙齒已經磨的非常平了,且脂肪層變薄,可推測身體非常虛弱,沒有捕食能力。

          流刺網纏繞瓶鼻海豚

          鯨豚死亡的另一原因,王浩文以日前到彰濱工業區處理一隻瓶鼻海豚的例子為見證,「牠身上有流刺網的漁網纏繞,死亡是不是跟流刺網的纏繞有關,就必須去證明及發現其原因,該隻海豚估計死亡三個星期以上,很多證據都消失了。解剖後胃是空的,代表死亡前已經有一段時間未進食,且皮下脂肪層也比較薄;一般海豚被漁網纏繞可能因為掙脫,有可能會嗆水,但這隻海豚沒有這個情況,沒有嗆水又被漁網纏繞,那牠死亡和漁網纏繞有沒有直接關係?」也有必要進一步去分析。

          王浩文說,「這次台東長濱擱淺藍鯨,很難過的發現其嘴上纏繞著漁網,而藍鯨進食方式是張嘴灌進大量海水至下巴,再閉起嘴靠腹部彈性縮回同時擠出海水,鯨鬚板會將小魚小蝦卡住,若無法正常張開即影響進食。」現在收集到的資料,知道這漁網是屬於某種捕漁法使用的漁具,但屬於哪一類的漁具還要送請專家分析。不過,至少可判斷跟漁業行為有關,而流刺網該不該禁一直有討論,全世界已開始反思友善漁具及友善漁業行為,聯合國永續目標十七項裡第十四項也提到重視海洋保護,這些都讓他深感責任重大,應努力還原與了解藍鯨死亡擱淺事件的原貌,看能否從這些證據上找到可以反過來提醒人類的事情。