Evaluation of Mitigation Measures for Highway Bird Road-kill

• Main Authors: Yung-Hui Hsu, 許永暉
• Other Authors: Ling-Ling Lee
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/62784433214874051116

碩士 === 國立臺灣大學 === 生態學與演化生物學研究所 === 98 === Birds are major road-kill victims on National Freeway No. 3 in Taiwan. Although acoustic barrier and roadside hedgerows are often suggested to be the mitigation measures for bird road-kill, only a few studies have been conducted to evaluate their effectiveness and the results were often contradictory. This study examined the effects of acoustic barrier (3m high) and roadside hedgerows of different height on the behavior of birds when flying across embankment roads or viaducts respectively on National Freeway No. 3. Between April-June and September-November 2008, bird behavior was recorded along road sections of known road-kill hotspots. The major bird victims are Columbidae, Passer montanus, Pycnotus sinensis, and Hirundinidae/Apodidae. Proportion of birds flying below 3m (height of acoustic barrier) were not significantly different between road sections with one-side or without acoustic barrier on either viaducts or embankment roads, but the proportion was significantly lower along road sections with acoustic barriers on both sides, which means that acoustic barrier on both sides could effectively facilitate birds to maintain their flying height when flying across the road, but not the one-side acoustic barriers. Proportion of birds flying below 3 m were significantly lower along road sections with high hedgerows than that of mid and low hedgerows, and the proportion along road sections of mid hedgerows are also significantly lower than that of low hedgerows on embankment roads. Proportion of birds flying below 3 m and 4.5 m were significantly lower along road sections with canopy height of road-side vegetation above viaducts. Although more birds maintained their flying height flying above 3 m when crossing over road sections with acoustic barriers on both sides or high hedgerows, such height is not enough for birds to avoid collision with trucks which are up to 4.5m in total height. Furthermore, birds may be attracted by acoustic barrier and road-side vegetation to perch and utilize, causing more chances of indirect pass and collision with cars.