The Correlation Between Cuckoo Diversity And Bird Diversity

Biodiversity conservation is an important issue in the approach to sustainable development,and the establishment of a basic system for measuring progress in biodiversity conservation is an important basis for achieving this goal.Because of the limitations of capital,labor,etc.,there is no good way to investigate widely all species in the region concerned.Therefore,the species of umbrella conservation,which is highly positively related to the diversity of other taxa,can be used as an indicator of biodiversity conservation in the selection or evaluation of protected areas.Birds are one of the most active components in the biota and they are very sensitive to the changes of various environmental factors and are often used as an indicator of the ecological environment.Hot bird indicator species include top predators,such as raptors,woodpeckers,and pheasants.In recent years,the common cuckoo(Cuculus canorus)as a reliable indicator of bird diversity has become a research hotspot.However,most previous studies focused on Europe where there are only two cuckoo species,and on the diversity and environmental assessment of cuckoos,while there were 17 species of parasitic cuckoo species in China.The present study investigated on the correlation between bird diversity and cuckoo diversity,and focused on the effective indicators of the cuckoos for bird diversity in China.The results were as follows:1.Sample collection was carried out during the breeding season in 2016 and 2017.In this study,a total of 2,4032 bird individuals belonging to 224 species,58 families and 18 orders were recorded in 18 sites of China.The occurrence rate of cuckoos was 1.4%in Wuzhishan City to 51.7%in Beijing City.2.The linear regression relationship between urban bird diversity and longitude(R~2=0.06,P<0.001,a=0.21,b=-17.96)and latitude(R~2=0.06,P<0.001,a=0.07,b=3.31)was significant.There was a significant linear regression relationship between the number of cities and the longitude(R~2=0.008,P=0.04,a=0.62,b=-48.01)and latitude(R~2=0.02,P=0.002,a=0.33,b=13.46).There was a significant linear regression relationship between the diversity of forest birds and longitude(R~2=0.11,P<0.001,a=-0.32,b=39.32)and longitude(R~2=0.11,P<0.001,a=-0.11,b=6.45).3.The species of cuckoos in all provinces are decreasing gradually from south to north.There was a positive correlation between latitude and urban cuckoo occurrence rate,a negative correlation between latitude and forest cuckoo occurrence rate,a positive correlation between latitude and urban cuckoo species,a negative correlation between latitude and forest cuckoo species,and a positive correlation between latitude and urban cuckoo number.There was a negative correlation between latitude and the number of forest cuckoo.4.At the local scale,the differences of birds among forests in Hainan were smaller,and the differences among cities were greater;on a large scale,the differences among birds in cities were smaller,and the differences among forests were greater.Homogenization of forest bird species was higher than that of urban bird species at small scale,while on large scale the homogenization of urban bird species was higher than that of forest bird species.However,the species number and dispersion degree of urban birds,Shannon-Weiner index and evenness index were all lower than those of forest birds,indicating that the species richness of urban birds was more conservative than that of forest birds.The results are consistent with those of other studies that suggested that human stress poses different evolutionary threats to different bird species.5.The average bird diversity of the samples with cuckoos was higher than that of the samples without cuckoos.In areas where cuckoo appears,the average bird diversity with cuckoo appearance is higher than the average bird diversity without the appearance of cuckoo.6.The difference of bird diversity among different species of cuckoo was significant(F=89.74,P<0.001).There was a significant positive correlation between the species number of cuckoo and bird diversity(R~2=0.16,P?0.001,a=1.91,b=1.30).There were significant differences in bird diversity among different species of cuckoo(F=67.04,P<0.001).There was a significant positive correlation between the number of Rhododendron and bird diversity(R~2=2.43,P?0.001,a=2.77,b=1.46).