Study On The Sleeping Rhythm Of Eurasian Siskin And Yellow-browed Bunting Under Artificial Light Interference

With the increase of night lighting in cities,many birds are affected by artificial lighting.Scholars in various countries have carried out relevant research.China's nighttime urban lighting engineering is at the forefront of the world,at the same time,China has abundant bird resources and is in the transit station of important global migration routes,and the ecological problems caused by light pollution are particularly prominent in China.Many animals are affected by light pollution,especially birds,the main victims,whose sleeping behavior are significantly compromised.In this study,to further expand the research species,selected the siskin and yellow-browed bunting,which are widely affected by light pollution in Tianjin.Birds'sleep behavior under the influence of LED lighting was studied in lab.Three irradiances in the lab:2 mW/m~2,5 mW/m~2,10 mW/m~2,and six kinds of light colors:orange,yellow,green,blue,purple and white light,were selected and utilized in the experiment.Natural light was applied on the birds of the baseline group.Then the sleep behavior of the siskin and yellow-browed bunting were recorded and analyzed.The results showed that the irradiances threshold for sleep of siskin in natural light was 0.47 mW/m~2,and the irradiances threshold for awakening was 0.27 mW/m~2.The irradiances threshold for sleep of yellow-browed bunting in natural light was 0.39mW/m~2,and the irradiances threshold for awakening was 0.62 mW/m~2.Increasing the artificial illuminance can delay their sleep onset,make the two kinds of birds wake up earlier,reduce their sleep amount and increase their wakening frequency.Different light colors have different effects on sleep behavior.For siskin,blue and green lights had greater influence on their sleep,while orange light and yellow lights had the least influence on this behavior.For yellow-browed bunting,yellow light had greater influence on sleep,while white light had less influence.For the same irradiance or light color,the sensitivity of these birds to falling asleep and awakening behavior is different.It can be seen that different species of birds have different response to the LED light with certain irradiance and light color.The experimental platform used in this study provides technical support for the follow-up study of other birds in this field.In this study,the effects of LED with different irradiance and wavelength on the sleep rhythm of siskin and yellow-browed bunting were obtained,which supplemented the database of the relationship between birds and artificial light,and would promote the development of ecological lighting engineering.