日本白鰻市場的需求分析

Demand Analysis of Anguilla japonica in Japan Market

本文的目的旨在分析全球日本鰻（又稱白鰻）的產量趨勢及各主要生產國產量的變化，並分析全球白鰻的主要消費市場日本的白鰻需求結構，透過價格對市場總規模及各來源數量變化的反應，觀察日本對各來源產品需求的特性，資料期間為2011年1月至2022年12月。其結果顯示：全球白鰻的產量在各國對鰻苗保育政策的重視與共識下，已有自低點回升的現象。其中日本及南韓產量已較穩定，中國產量穩定成長，比較特別的是臺灣白鰻的產量仍然位於歷史低水位且波動大。日本白鰻消費市場的近似理想逆需求體系（inverse almost ideal demand system; IAIDS）的結果顯示：臺灣白鰻的進口量對日本白鰻需求市場的價格有重要影響力。其中，規模彈性（絕對值）以日本批發市場活鰻最小，自臺灣進口產品的規模彈性小於自中國進口的產品，說明隨著日本市場對白鰻需求規模的提高，日本批發市場活鰻價格最穩定，來自臺灣產品價格的下降幅度相對於來自中國的產品為小且穩定。自身價格反應彈性顯示日本消費者對於來自日本批發市場的國產品牌活鰻有特別偏好，自臺灣進口的活鰻與調製鰻對數量變化的價格敏感度高於來中國的產品，說明自臺灣進口活鰻及調製鰻在日本白鰻需求市場的重要性比中國產品為高。交叉價格反應彈性顯示自臺灣進口的活鰻與中國進口的產品（包含活鰻及調製鰻）有數量互補關係，與日本批發活鰻有數量替代關係；臺灣活鰻進口量對日本批發市場價格的影響亦高於來自中國的產品。整體市場規模的大小對各來源價格的影響程度仍遠高於各來源產品數量變動對價格的影響力。

The aim of this article is to analyze the demand structure of Anguilla japonica in Japan by observing price responses to changes in total market scale and quantities from different sources in the Japanese market. The data covers the period from January 2011 to December 2022. Global Japanese eel production has rebounded from its low point due to the attention and consensus of various countries on eel conservation policies. Japan and South Korea have maintained relatively stable production, while China's production has been steadily growing. Notably, Taiwan's production remains at a historically low level and fluctuates greatly. The IAIDS model shows that Taiwan's products have lower scale flexibility compared to those imported from China, resulting in price decreases at a smaller and more stable rate as the market scale increases. The study found that Japanese consumers preferred domestic brands of live eels from the wholesale market, while live and prepared eels imported from Taiwan were more sensitive to price changes in quantity compared to products from China. This suggests that live and prepared eels from Taiwan are more important in the demand market for eels in Japan than products from China. The cross-price flexibility showed that live eels imported from Taiwan had a quantity complementary relationship with products imported from China (including live eels and prepared eels) and a quantity substitution relationship with Japanese wholesale live eels. The quantity of live eels imported from Taiwan had a greater impact on the wholesale market price in Japan than those from China. The price of each source is still significantly more affected by market size than by changes in the quantity of each source.