报告

作者

日期

eBird记录 S48852838

地点

Chimney Swift Roost--Downtown Raleigh
Wake, North Carolina, United States
该地点产生的媒体文件 配图名录
地图
地图 坐标: 35.7786554, -78.6404747
年龄
未说明
性别
未说明
发声
鸣叫; 飞行鸣叫
回放
未使用回放

媒体文件注释

Large migratory flock about to enter roosting chimney, 19:16 EDT

观察细节

This is a well-known roosting chimney. The leader estimated an even higher number, so this is a conservative estimate. The birds managed to enter the chimney within three minutes, so more than 700 pouring into the chimney per minute is unlikely. Began to enter the chimney in force at 19:25 and were all in before 19:28. Sample estimates of the flying birds: 25 at 18:45; 200 by 18:50; 300 by 18:55, 600 by 19:05; 1100 by 19:10, 1500 by 19:15, 2000 by 19:20; formed a lorus (doughnut) several times over us, quite low, then entered the chimney between 19:25 and 19:27 (19:28).

技术信息

录音机
Nikon CoolPix S7000 MOV converted to WAV by Convertio.co
话筒
附件
原始文件大小
6.21 MB