Distribution and foraging behavior of Little Egret Egretta garzetta in the aquaculture ponds of Augo area

• Main Authors: Tun-Guan Zo, 鄒騰冠
• Other Authors: Fu-Hsiung Hsu
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/77965831259882054663

碩士 === 國立嘉義大學 === 生物資源學系研究所 === 101 === For nearly a century, due to human development, the world's natural wetlands disappeared more than 50%, and most of them have been developed for industrial, agricultural farms, or aquaculture fish farms. Although the disappearance of natural wetlands habitat for many waterbirds reduction, but like aquaculture ponds of these wetlands, still retains the characteristics similar to natural wetlands, providing habitat for waterbird use. Little Egret Egretta garzetta in Taiwan is a common resident bird, often in fish ponds Aogu roost in flocks or foraging activity. This study is divided into three parts for little egret fish farms in Aogu habitat distribution and foraging behavior are discussed. The first part is more sun pool and pond full of turtles, as well as three different sizes of fish farms little egret perched on the number of seasonal variation. It was found that in summer the recorded number of little egrets were less than in other seasons, and each season of the sun recorded in the fish ponds are relatively small number of egrets pond full of turtles and more; while three different types of fish farms as recorded in the area of small egret large number of fish ponds up to begin with. The second part is to explore fish farms around the houses, roads, ditches and grass and other environmental factors on the impact of the number of small egret perched. The results showed that the number of little egret habitat will be a variety of environmental factors, fish ponds are surrounded by a large road through Little Egret recorded fewer; while the premises will also affect the habitat of little egrets. The third part is the fish farms of different sizes by the Little Egret behavioral observations to investigate the fish pond area for little egrets foraging behavior. The results showed a large area Little Egret foraging fish farms more time, warning time there along with an increase in the area of fish farms decreasing trend; while Little Egret foraging frequency, capture frequency small area of fish farms are the highest, but the success rate in a different area of capture fish farms no significant differences between. Summarize the findings of this study, a small fish pond Aogu egret perched quantity, will be the season, the water level state fish farms, an area surrounding the impact of factors; while Little Egret foraging behavior in fish farms, fish ponds will also be area size.