Knowledge Network Node
Marine Fisheries. 2019, (04) Core

Dietary and feeding intensity of female Eriocheir sinensis in the Yangtze River Estuary during migratory periodChinese Full TextEnglish Full Text (MT)

XU Jing-jing;GENG Zhi;FENG Guang-peng;ZHUANG Ping;WU Xiao-feng;HUANG Xiao-rong;SHEN Ang-lv;WANG Hai-hua;East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences;College of Fisheries and Life Science, Shanghai Ocean University;Jiangxi Institute for Fishery Sciences;

Abstract: Eriocheir sinensis is an important economic aquatic animal, and the Yangtze River Estuary is an important reproductive migration place for Eriocheir sinensis. In recent years, Eriocheir sinensis resources have declined sharply due to overfishing, reclamation activities and habitat degradation in the Yangtze River Estuary. The protection of Eriocheir sinensis has attracted extensive attention. At present, enhancement and releasing, habitat restoration are important remedies for protecting the population. As the most important life stage in the life history of Eriocheir sinensis, spawning period is the key stage to determine its population resources. In this study, gastric content analysis was used to analyze the food composition, food difference of female crab before and after spawning in the Yangtze River Estuary. It can provide a reference for food types and food amount in artificial habitat restoration. It is of great significance for the protection and rational utilization of Eriocheir sinensis. It also supplements the basic biological knowledge of Eriocheir sinensis. The feeding composition, feeding intensity and trophic level were analyzed by the gastric contents of female crab collected from October 2017 to April 2018 in Chongming East Beach（121°58′～122°12′E、31°05′～31°22′N） of the Yangtze River Estuary by trawling.The results showed that the feeding rate, food fullness index and mean gastric fullness index of female crab had obvious monthly changes. The indexes before the spawning were the highest in October-November（autumn） and the lowest in December-February（winter）. After spawning, the indicators were the lowest in December-February（winter） and the highest in March-April（spring）. The female crabs in the migratory stage had various feed sources, including Bacillariophyta, Pyrrophyta, Cyanophyta, Chlorophyta, Crustacea, Polychaeta, fish, Mollusca, Echinodermata, eggs, aquatic plants, detritus, rubbish etc, belonging to omnivorous aquatic animals. Algae, detritus and Crustacea were the main diets of female crab before spawning, and frequency percentage was 68.13%, 54.76%, 19.05% respectively. Algae, detritus and aquatic plants were the main diets for female crabs after spawning, and frequency percentage was 70.35%, 73.91%, 25.39% respectively. There was a significant difference in food composition of female crab before and after spawning（χ~2=21.57, P＜0.05）. The food composition contributing most to the differences were detritus（χ~2=8.32）, Crustacea（χ~2=5.49） and aquatic plants（χ~2=4.02）. The trophic levels of female crabs before and after spawning were 3.60 and 3.10, and the average trophic level was 3.35. Thus, the crabs belonged to the third trophic level animals.The female crab before and after spawning did not stop eating in the migration stage, and their food sources were diverse. Therefore, during the reproductive period of female crab, sufficient food conditions can be provided to improve the reproductive performance of spawning population.
Keywords：

Yangtze River Estuary; Eriocheir sinensis; feeding composition; feeding intensity; trophic level;

  • DOI：

    10.13233/j.cnki.mar.fish.2019.04.002

  • Series：

    (D) Agriculture

  • Subject：

    Aquaculture and Fishery

  • Classification Code：

    S917.4

Download the mobile appuse the app to scan this coderead the article.

Tips: Please download CAJViewer to view CAJ format full text.

Download: 361 Page: 397-407 Pagecount: 11 Size: 997K

Related Literature
  • Similar Article
  • Reader Recommendation
  • Associated Author