| 中文摘要 |
「沿近海重要漁業資源管理與利用之調查研究-魩鱙、鰻魚、白帶魚、蟹類及鯊魚加工」之中文摘要： 一、「臺灣周邊海域魩鱙資源變動及管理機制調整研究」 摘要 魩鱙漁業為臺灣本島沿岸水域常見的小型漁業。 此漁業之漁民於每年之春(3 ~ 5月)及秋(9 ~ 11月)兩季，在沿岸水域，撈捕鯷科及鯡科仔稚魚為標的。 1990年前後，年漁獲量約在1000 t 左右，近年則只在500 ~ 700 t 左右盤旋。 本年計畫持續收集魩鱙漁業之更新資料，俾觀察每年之變動情形，同時亦統合整理歷史資料，檢討及建議管理方向。 漁業署於2009年將魩鱙漁業之漁撈日誌收集系統建置完畢。 本(2012)年為第4年之資料收集。 2012年共獲得9,241筆資料，較2011年之7,662筆資料，增加1,639筆資料錄，此資料組反應6,770個作業日及13,873個作業網次(包括大目袖綱、流袋網及其他網具)。 全年之漁獲量為935.6 t，平均每一趟出海得138 kg。 本漁業總年產值為168.9百萬元，平均單價為180.5 元/公斤。 本(2013)年春季漁獲概況顯示：東北水域之作業首日為4月8日(98 Julian days, Jd)，但漁獲之狀況不佳， 4月20日(110 Jd)才達到漁獲量的峰值，3.6 t的單日到岸量，呈現漁期較晚，且魚群密度不高。 西南水域之正式漁期由2月5日開始，但沒有強的添加群，只是形成漁期的暖身而已；直到3月4 ＆ 5日，每日達3 t的到岸漁獲，高峰而後，走向下斜陡坡，直到漁期結束。 2013年春季資料收集及初步分析完成，惟猶待秋季資料之匯入，並總結之。 漁獲之物種組成方面，東北水域之魚種組成，主要有四個魚種，分別是日本鯷(Engrailis japonicus, 47.2 %)，刺公鯷(Encrasicholina punctifer, 24.6 %)，異葉公鯷(Encrasicholina heteroloba, 9.7 %)，及黃小砂丁(Sardinella lemuru, 8.5 %)。 西北水域主要魚種為刺公鯷(28.5 %)，次為日本鯷(16.2 %)及異葉公鯷(20.9 %)。 西南水域之魚種組成維持穩定，主要魚種為異葉公鯷(61.8 %)，而刺公鯷所佔亦高，達到35.4 %。 兩者已合占約九成五以上的漁獲物。 混獲之魚種組成顯示：東北水域春季的混獲情形較往年為低，僅達6.56 %，西北水域混獲只佔7.78 %，西南水域的混獲率估為1.41 %，與去(2012)年相較，去年之混獲率相對低，今年則更低，回復到往年約5%之水平。 全島之混獲最主要的五個物種是蛇鯔 (0.90 %), 粗紋鰏(0.81 %), 花斑蛇鯔(0.62 %), 三鰭鳚(0.48 %), 及小牙鰏(0.33 %)。 東北水域之歷年資料發現今(2013)年的資源強度在本春季屬於相對低迷的漁業景況，秋季漁期稍微彌補回來；西南水域目前之作業規模屬於適正水平。 二、「人工放流鰻魚之效益評估」 日本鰻是亞洲水產養殖的重要魚種，但因人工繁殖尚無法商業化量產鰻苗，因此養殖所需的大量鰻苗皆依賴天然捕撈。根據統計，現今的日本鰻天然資源量相較於1970年代而言，估計低於當年的10 ﹪，因此鰻苗的缺乏，遂成為養殖產業的嚴重瓶頸。日本鰻主要的養殖國家為日本、中國、韓國、以及台灣，每年鰻苗的總需求量約在100公噸左右，台灣年平均需求量約20公噸以上，但本省鰻苗的捕撈量，近年來平均在5公噸以下，鰻苗不足的缺口頗大，在鰻魚資源日益下降的情況，如何管理與復育日本鰻的資源，為台灣以及東亞鰻魚產業永續發展的關鍵。而人工增殖放流，為增加降海種鰻的手段之一。本年度計畫分別選定在北部新竹縣鳳山溪及頭前溪、南部高屏溪和東部宜蘭縣宜蘭河，進行日本鰻標識放流工作，並於宜蘭縣宜蘭河進行日本鰻成鰻之無線電標識放流，對於其遷徙習性之動態進行分析，並進行放流後之回收評估工作，期能建立一有效增殖鰻魚資源之方法。本年度計畫已完成鳳山溪、高屏溪及宜蘭河之放流回收工作以及宜蘭河無線電標籤記錄，綜合結果如下: 一、鰻魚放流後的回收: 迄2013年11月底為止，共採集野生鰻253尾，放流鰻36尾 (雌23隻、雄13隻)，宜蘭河回收到的成鰻共24尾，其中有晶片的有9尾，回收率為2.8%、頭前溪及鳳山溪所回收到的鰻魚總共有3尾，回收率為0.36%，而高屏溪回收到的鰻魚有9尾，其回收率為1.9%，今年度各溪流鰻魚的回收率較往年偏低。 二、回收鰻生長與成熟情形: 宜蘭河回收鰻集中在2012年12月初捕獲。因此其體長無明顯變化，體重僅有略微下降的情形，其GSI平均值0.62，黃鰻與銀鰻皆有。其他河川並未捕獲到有晶片的鰻魚。 三、無線電標識鰻追蹤情形: 迄2013年11月底為止，共偵測到15尾無線電標識鰻魚，以GPS定位後描繪其路徑，顯示出其整體路徑往下游移動，與野生銀鰻陸續降海之習性相符。 四、協助辦理鰻魚之保育宣導工作: 本計畫已協助蘭陽博物館舉辦『白金傳奇-臺灣鰻魚展』(2012/11/27 – 2013/05/05) 之策展與相關宣傳與教育活動。 五、東亞各國日本鰻資源、棲地環境調查與復育相關資料: 2010、2011、2012、2013年，亞洲日本鰻苗總捕獲量遽降為41、35、26、19公噸，台灣在最近4年 (2010-2013) 的鰻苗捕撈量僅分別剩下4.2、4.2、1.9、1.5公噸，迭創歷史新低。 三、「白帶魚資源動態解析之研究」 本計畫為科技保密計畫，故不引入相關資訊，請另參照細部計畫期末報告紙本。 四、「海峽北部蟹類漁業資源之調查評估」 蟹類資源是台灣海峽北部漁業中主要漁獲物之一，為確保台灣海峽北部蟹類資源之永續利用，本研究計畫主要的目的是針對海峽北部蟹類漁業資源進行調查與評估，擬先對過去台灣底拖網漁業在台灣海峽北部蟹類資源之漁業統計資訊及其時空分佈(含努力量、漁獲量及CPUE等)進行研析，並針對目前台灣漁船在台灣海峽北部分對蟹類資源之利用現狀與動態進行統計與調查，最後亦針對目前台灣海峽北部蟹類資源之漁獲組成之時空間變化加以調查，並進行漁船作業漁撈日誌之設計及委託，以利於目前漁獲努力量、漁獲量及CPUE之時空分布特性之收集與研析，並提出管理之建議。 分析由臺灣大學海洋研究所底魚中心所提供之臺灣歷年單(1970~2010年)、雙(1970~1989)拖網漁船作業日誌資料，顯示海峽中北部區域為蟹類資源較豐富之區域，其主要分布範圍在北緯24-26度半、東經120-125度間，其主要盛產期為冬季，約在11-1月間，但單拖網之漁獲蟹類資源之位置較雙拖網者偏北偏東；分析拖網歷年之CPUE變化，顯示總體蟹類單位努力漁獲量從早期一直下降至2001到最低點，2001後蟹類之CPUE值有上升之趨勢。 分析3~10月籠具之作業日誌資料，顯示(1)、臺灣北部之蟹類籠具漁船主要作業區域為北緯25-27度、東經121-123度間；(2)主要蟹類漁獲物組成為繡斑蟳、紅星梭子蟹及善泳蟳，但以鏽斑蟳之數量最多；(3)、紅星梭子蟹之雌雄體寬範圍在88-180 mm，6~8月時有較小型蟹加入漁場；繡斑蟳體長分佈從70-180 mm，6~10月時皆有較小型蟹加入漁場；(4)鏽斑蟳CPUE月別變化顯示，3~7月之值皆在20克/籠具數以下，8月份以後則有較明顯的增加；紅星梭子蟹8月份CPUE值有明顯上升，4-7月時則相對有較低 (小於10克/籠具數)。為配合政策之需要，從8月起亦加入主要漁獲蟹類之生殖生物學之研究，將推估包含50%最小成熟體寬之估計，以供相關單位決策之參考。 五、「鯊魚之加工利用國內消費及進出口研究」 本計畫為科技保密計畫，故不引入相關資訊，請另參照細部計畫期末報告紙本。 |
| 英文摘要 |
Abstract of "Investigations on Reasonable Utilization and Management Plans for Major Coastal and Neritic Resources-Anchovy larvae,Eel,Cutlassfish,Crab and Shark": 1. "Monitoring resouce fluctuatuion in Taiwanese Bua Fisheries and reviewing management plan" : Larval fisheries, being called “Bua” fisheries in Taiwan are commonly found in the coastal areas. The local fishermen seek after engraulid (anchovies) and clupeid (herrings) larvae in spring (Mar ~ May) and fall (Sep ~ Nov). During 1990’s the annual landing was accounted to 1,000 t, while in the last ten years barely 500 ~ 700 t were landed. This annual project keeps on collecting data from Bua practices in order to monitoring the fishery resources and updating annual management plan. A comprehensive logbook collection system has been constructed by Fisheries Agency in 2009, and thus the 2012’s data were the fourth complete annual data complemented into the system. In 2012, we found 9,241data records, which are 1,639 records surplus to that of 2011 (7,662 records). The dataset included 6,770 boat-trips, and 13,873 net throws; including large-wing, fyke and fork –hand nets. The harvest was summed to 935.6 t and averaged 138 kg boat-trip-1, and the amount valued 168.9 million NTD, with an averaged unit price of 180.5 NTD kg-1. The data collected in spring 2013 is compiled, and will be concluded next project term. In the 2013’s spring, it exhibited that the starting date of practice was on April 8 in NE waters, but the fishing condition was far from good. The condition improved on April 20, when 3.6 t was landed in a single day, indicating a late starting season and sparse harvest. In SW water, the fishing season started on February 5, when catch was not strong but reflected a status of seasonal formation process. In March 4 ＆ 5, daily landings improved to 3 t. From this peak onward, the fishing condition went down quickly, and that declared a dying stage of the spring fishing season. The Bua catches was composed of 4 major species; i.e., Japanese anchovy (Engrailis japonicus, 47.2 %), Buccaneer anchovy (Encrasicholina punctifer, 24.6 %), shorthead anchovy (E. heteroloba, 9.7 %), and yellow sardine (Sardinella lemuru, 8.5 %) in NE waters; Buccaneer anchovy (28.5 %), Japanese anchovy (16.2 %) ＆ shorthead anchovy (20.9 %) in NW waters; and shorthead anchovy (61.8 %) and Buccaneeer anchovy (35.4 %) in SW waters. The by-catch percentages were estimated 6.56 % in NE, 7.78 % in NW and 1.41 % in SW; reflecting a low by-catch rate in 2013’s spring. Taken as a whole, the top 5 species being by-caught were Saurida wanieso (0.90 %), Leiognathus lineolatus (0.81 %), Saurida undosquamis (0.62 %), Tripterygion inclinatus (0.48%), and Gazza minuta (0.33%). Finally, we saw recruitment in NE was low in spring but recovered in autumn during 2013, and that in SW was pretty fair in both season. 2. "Benefit Evaluation of Stock Released Japanese Eel" : Japanese eel is an important aquaculture species in Taiwan with very high economic benefit. Because the commercial scale of artificial propagation of the glass eel has not been established yet, the needed fries are all caught from the wild. This results in a serious bottleneck for the aquaculture industry. It is estimated that the current eel resource in Taiwan also suffers the same impact. The Japanese eel is mainly cultured in Taiwan, China, Korea, and Japan, with mean elver demands about 100 metric tons annually. Taiwan needs about 20 tons for aquaculture but only catches less than 5tons in recent years. Thus, to manage and recover the valuable eel resource is a key for the sustainability of eel aquaculture industry. An efficient Japanese eel releasing method is one of the methods to increase migratory eels. The Fengshan River, Touchan River, Yilan River and Kaoping River of Taiwan will be selected for eel mark-releasing location. In addition, the radio-tagged silver eels were performed in Yilan River. Their life history dynamics and downstream migration will be traced to evaluate a better stock releasing strategy. The five results of the project are: 1. The re-catch of the eel: till Nov. of 2013, a total of 253 wild and 36 released (Female: 23, male: 13) eels were caught. 24 eels were caught from Yilan River (re-catch rate 2.8%, 9 eels with chips). 3 eels were caught from Fengshan and Touchan Rivers (re-catch rate 0.36%). 9 eels were caught from Kaoping River (re-catch rate 1.9%). The average re-catch rates were lower than they were before. 2. Growth and maturation of the re-catch eels: The re-catch eels from Yilan River were mainly concentrated around Dec. 2013, thus there were no significant change on total length and only slightly decrease on body weight. The mean GSI was 0.62, which covered both yellow and silver eels. 3. Tracing of the radio-tagged eels: till Nov. 2013, 15 tagged eels were detected. Their migratory routes were identified by GPS. The overall movement was toward the lower reach, similar to those of the wild eels. 4. Promotion of eel conservation: We had designed the Eel Expo in LanYang Museum between 2012/11/27 – 2013/05/05 and help the related promotion and education activities. 5. Collection of eel resource information: During years 2010、2011、2012、2013,The total annual catch of the Japanese glass eel in East Asia were 41、35、26、19 tons, respectively. The catches in Taiwan were 4.2、4.2、1.9、1.5 tons, respectively. The eel resource seems to become lower and lower. 3. "Studies of stock dynamics and assessment for cutlassfish" : 本計畫為科技保密計畫，故不引入相關資訊，請另參照細部計畫期末報告紙本。 4. "Survey and assessment for crab fisheries resources in north of the Taiwan Strait" : The purpose of this project is to survey and assess the crab resources in north of the Taiwan Strait. The main tasks include (1) to analyze the Taiwanese trawler fisheries’catch and effort statistics in north of the Taiwan Strait and to obtain the historic trend of abundance indices of the crabs resources, (2) to survey the amount and dynamics of fishing boats aimed at the crabs in north of the Taiwan Strait and to measure and obtain the size-frequency data, (3) to examine the main species composition of crabs from north of the Taiwan Strait, (4) to design the logbook and develop the retrieval channel of logbook. According to the logbook data of Taiwanese pair (1970~1989) and otter(1970~2010) trawlers fisheries’ catch and effort statistics, there is more abundant crab resources in the center and north of Taiwan Strait, and it distributes between 24 degree and 26.5 degree north and between 121 degree and 123 degree east. The main fishing season is during winter (from Jan. to Dec.). The CPUE trend shows that the value decreases from 1970 to 2001 and CPUE increases after 2001. According to the logbook data from the specimens of crab-trap fishing in 2013 (from Mar. to Oct.) showed that (1) the main fishing areas were between 25 degree and 27 degree north and between 121 degree and 123 degree; (2) the main fishing species were Charybdis feriatus, Portunus sanguinolentus and Charybdis natator in the northern waters of Taiwan Strait, and the most abundant species is Charybdis feriatus; (3) the crab width of is Portunus sanguinolentus between 88 and 180 mm, and the smaller crab was found from June to Aug; the crab width of is Charybdis feriatus between70 and 180 mm, and the smaller crab was found from June to Oct.; (4) the CPUE values of Charybdis feriatus were lower (beneath 20g/pot) from Mar. to Jul, and one increased from Aug; the CPUE values of Portunus sanguinolentus were lower (beneath 10g/pot) from Apr. to Jul, and one also increased from August. 5. "Study of shark fin processing and utilization on domestic consumption and its trade" : 本計畫為科技保密計畫，故不引入相關資訊，請另參照細部計畫期末報告紙本。 |