澎湖竹灣海域棲居於延繩式養殖牡蠣串之動物相

Fauna in Longline Oyster Farm in Jhuwan Waters, Penghu, Taiwan

本研究為調查澎湖縣竹灣海域延繩式養殖牡蠣周遭的生物。採樣時間為2018年7－8月與2019年7－8月。結果發現2018年之採獲物種的組成共7門32科38屬49種生物，採獲頻率分析則以少見與稀有漁獲種類為主，共佔92％；2019年之採獲物種的組成共4門9科10屬11種生物。由此可知此生態系的主要組成為少見與稀有物種，而較為多元的組成特性物種間的可取代性高，生態系亦較為穩定。比較2017年底與2018年底冬季海溫，發現前者皆大約較後者低，推測影響2019年物種數與量的原因在於，2018年的冬季不夠寒冷，無法在此海域以大型藻類累積冬季的營養鹽。

This study was conducted to investigate the basic fauna information in the longline oyster farm in the Jhuwan waters of Penghu County, Taiwan. Samples were collected from July to August in 2018 and 2019, respectively. A total of 49 samples, including 49 species, 38 genera, and 32 families from seven phyla, were obtained in 2018. Analysis showed that rare and scarce species had the highest appearance frequency, making up 92% of total samples. A total of 11 samples, including 11 species, 10 genera, and nine families from four phyla were obtained in 2019. Analysis showed rare species had the highest appearance frequency, reaching 82% of total samples. We conclude that the main inhabitants in this ecosystem are rare and scarce species, and the high fauna diversity allowed replacements of species. The ecosystem was thus more resilient. Comparison of sea temperatures in late 2017 and 2018 showed that 2018 was warmer, which could have adversely impacted species numbers and population in 2019, as warmer climate caused reduced nutrients and therefore lower seaweed growth in the winter.