McCafferty D J., Moncrieff J B., Taylor I R.
Department of Adult and Continuing Education, University of Glasgow, 59 Oakfield Avenue, Glasgow G12 8LW, UK
J Therm Biol. 2001 Jun;26(3):193-203. doi: 10.1016/s0306-4565(00)00042-5.
(1) The energy savings associated with the roosting behaviour of barn owls (Tyto alba) were determined with a biophysical model using measurements of microclimate from a roost and nest site in SW Scotland (55 degrees 10' N 3 degrees 12' W) from April 1991-March 1992. (2) The roost building provided complete shelter from wind and precipitation. Air temperature inside the roost building was 1.4 degrees C greater than ambient and matched the seasonal change in temperature. Air temperature inside the nest box was on average only 0.8 degrees C greater than ambient but was 2-3 degrees C warmer when adults and chicks were in the nest during the breeding season. (3) Estimated metabolic heat production was significantly different between locations and averaged 67.9, 68.1, 75.5 and 84.2Wm(-2) for a barn owl roosting in the building, nest box, spruce tree and in the open, respectively. At night metabolic heat production was greater by 4-12% compared with daytime, depending on location. (4) Heat loss was 30% greater in winter months than in the summer in all locations. By roosting in the building an owl would make savings of 21.6Wm(-2) in March but only 12.9Wm(-2) in August. In a tree roost a barn owl would save 11.8Wm(-2) in March and 5.8Wm(-2) in August. (5) Barn owls were estimated to reduce metabolic heat production by 19% by roosting in the building and by 10% by roosting in a tree. In the building and tree savings of 21 and 9% occurred during the day compared with 17 and 12% at night. (6) Metabolic savings were strongly dependent on weather conditions with average metabolic savings of 26% occurring in wet and windy conditions compared with only 12% on dry-calm days. Maximum savings of 29-36% occurred on wet days. (7) Barn owls appear to compensate for high metabolic demands for heat production by taking advantage of better thermal conditions within buildings, especially during the day when metabolic savings are greatest.
（1）利用生物物理模型，通过对1991年4月至1992年3月间苏格兰西南部（北纬55度10分，西经3度12分）一个栖息和筑巢地点的小气候测量，确定了仓鸮（Tyto alba）栖息行为所带来的能量节省。（2）栖息建筑提供了完全防风防雨的庇护。栖息建筑内的气温比环境温度高1.4摄氏度，且与季节温度变化相符。巢箱内的气温平均仅比环境温度高0.8摄氏度，但在繁殖季节成年仓鸮和雏鸟在巢中时，巢箱内的温度要高2 - 3摄氏度。（3）不同地点的估计代谢产热显著不同，仓鸮在建筑内、巢箱内、云杉树上和露天栖息时，平均代谢产热分别为67.9、68.1、75.5和84.2Wm(-2)。夜间代谢产热比白天高4 - 12%，具体取决于地点。（4）所有地点冬季的热量损失都比夏季大30%。通过在建筑内栖息，仓鸮在3月可节省21.6Wm(-2)，但在8月仅节省12.9Wm(-2)。在树上栖息时，仓鸮在3月可节省11.8Wm(-2)，在8月可节省5.8Wm(-2)。（5）据估计，仓鸮通过在建筑内栖息可将代谢产热降低19%，在树上栖息可降低10%。在建筑内和树上，白天的节省分别为21%和9%，夜间分别为17%和12%。（6）代谢节省强烈依赖于天气条件，在潮湿有风的条件下，平均代谢节省为26%，而在干燥平静的日子里仅为12%。在潮湿的日子里，最大节省可达29 - 36%。（7）仓鸮似乎通过利用建筑内更好的热条件来补偿产热的高代谢需求，尤其是在白天代谢节省最大的时候。
