2004～2016年鸭绿江下游集群繁殖的鹭类巢区分布与变化
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摘要
2004～2016年,为了监测鸭绿江下游集群繁殖的鹭类巢区的分布及变化,采用巢区搜寻、样方调查和统计计数的方法,在鸭绿江下游共发现集群繁殖的鹭类7种,分别为苍鹭(Ardea cinerea)、大白鹭(Egretta alba)、小白鹭(Egretta garzetta)、中白鹭(Ardea intermedia)、夜鹭(Nycticorax nycticorax)、池鹭(Ardeola bacchus)和牛背鹭(Bubulcus ibis),共有繁殖巢区21处,其中16处分布于东港市境内,占总繁殖巢区数量的76%;鹭类多在丘陵或山地集聚,套里夹心子岛是唯一一处鹭类的江心洲营巢区;鸭绿江下游鹭类营巢历史分段明显,60～100 a的营巢点约占20%;截止到2016年,有4处巢区的鹭类已经迁离;2016年,研究区共分布有10 731个鹭类的巢,平均在每株树营巢2.45个,巢的平均高度为9.45 m,有巢的树的平均直径为20.8 cm;在鹭类营巢的树种中,属天然次生林的树种有辽东栎(Quercus wutaishansea)、刺槐(Robinia pseudoacacia)和胡桃楸(Juglans mandshurica)等,此外还有落叶松(Larix gmelinii)、红松(Pinus koraiensis)、沙松(Abies holophylla)和杨(Populus spp.)等人工林,长白落叶松(Larix olgensis)是所有巢区中遇见率最多的树种;在东港市马家店镇东双山分布的鹭类总巢数最多,为2 500个巢;面积最大和最小的巢区分别为老油库巢区和凤城市后屯1处的巢区;单株营巢树上的最大巢数为25个,见于前阳镇老油库的刺槐林;在粗大的营巢树木上,鹭类的巢较高、巢数较多;滨海平原的鹭类多样性(7种)显著高于北部低山区(2种);北部低山区巢的平均高度(14.6 m)、营巢树木直径(30.8 cm)都显著大于南部滨海丘陵区(巢平均高度为7.84 m,营巢树木的平均直径为17.7 cm);大白鹭为北部低山区和南部滨海丘陵区共有的常见鹭类,苍鹭也偶尔分布于南部丘陵区;苍鹭偏好河流生境,迁来时间较早,通常在清明节开始集聚;8月下旬,鹭类在巢区周围水域集结,准备南迁。自2004年开始,鹭类分布区呈扩张趋势,2004～2005年鹭类分布区扩张幅度最大,滨海平原是鹭类巢区扩张的主要区域;2004～2012年,鹭类的繁殖数量也逐年增加,其中,2010～2012年,鹭类数量剧增,而2012年之后,鹭类的繁殖数量趋于平稳。营巢树木死亡、人类干扰和可能的鹭类最佳巢区再选择是原有鹭类巢区消失的主要原因,避免人类干扰是维持巢区恒定的主要措施;应该扩大现有的鹭类保护区的面积,建立新的保护网点;应该开展更大范围的繁殖鹭类的分布区调查,确定其巢址选择的地形和生态因子,科学估算鹭类种群生产力,为实施区域生态旅游奠定基础。
From 2004 to 2016, monitoring upon distribution of nest areas of cluster breeding herons was done through nest area searching, sampling and counting in the lower reaches of the Yalu River,meanwhile 7 species of herons and egrets were found breeding in this area, they are great egret(Egretta alba), little egret(Egretta garzetta), intermediate egret(Egretta intermedia), cattle egret(Bubulcus ibis), grey heron(Ardea cinerea), Chinese pond heron(Ardeola bacchus) and black-crowned night heron(Nycticorax nycticorax).Within the study area, 21 breeding sites were found, including 16 breeding sites(about 76%) in Donggang city, and breeding egrets clustered around the hills. Taoli islet is only nest area in the plain. The 20% nest sites continued 60 years to 100 years already, different from those new sites in the lower reaches of the Yalu River.By the end of summer of 2016, 4 former breeding sites disappeared. Total nest numbers was 10 731, mean number of nests in a nest tree was 2.45, the mean of nest height was 9.45 m, and mean diameter of the nest tree was 20.8 cm in 2016. Nesting trees belonged to natural secondary forest, including Quercus spp., Robinia pseudoacacia, Juglans mandshurica; and planted forests, including larix spp., Pinus korainensis, Abies holophylla and Populus spp. Larix olgensis was the most familiar species in all nest areas. The 2 500 nests,the maximum was found in Eastern double hills in Majiadian town in Donggang city. The maximum and minimum areas of nests were found in Donggang and Fengcheng city. The maximum numbers of nests were25 found in Robinia pseudoacacia trees in Old oil depot in Qianyang town. Rough trees were with more nests and higher nest height. Diversity of egrets was greater in seashore plain than that in north hills. Nest height(14.6 m) and diameter of nest trees(30.8 cm) in north hills were greater than those in south coastal plain with lower nest height(7.84 m) and less diameter of trees(17.7 cm). Great egret was the specie between northern mountains and southern coastal hills, but grey herons occasionally came to southern coastal hills for nesting.Usually grey herons prefer to river surroundings, come to breed earlier and cluster in Qingming festival.Egrets gathered for southward migration in mid-August in the wetlands of the nest area. Since 2004, the distribution of nest area has been widened, especially from 2004 to 2005; numbers of breeding egrets increased. Comparing the two periods; from 2004 to 2005 and from 2010 to 2012, the maximum of increasing rate occurred from 2010 to 2012. However the rise was getting pretty little after 2012. Coastal plain was the main expansion area for nesting. Nest area disappeared mostly caused by the death of the trees, disturbance of human being, and re-selecting breeding sites. Avoiding human disturbance was the most important measure to stabilize nest area, and as well much larger protected area should be expended, therefore more breeding sites could be selected. For implementing the regional ecological tourism, distribution of breeding herons should be found out on a larger scale, topographical and ecological factors should be defined to the selection of the nest sites, and productivity of population should also be estimated.
From 2004 to 2016, monitoring upon distribution of nest areas of cluster breeding herons was done through nest area searching, sampling and counting in the lower reaches of the Yalu River,meanwhile 7 species of herons and egrets were found breeding in this area, they are great egret(Egretta alba), little egret(Egretta garzetta), intermediate egret(Egretta intermedia), cattle egret(Bubulcus ibis), grey heron(Ardea cinerea), Chinese pond heron(Ardeola bacchus) and black-crowned night heron(Nycticorax nycticorax).Within the study area, 21 breeding sites were found, including 16 breeding sites(about 76%) in Donggang city, and breeding egrets clustered around the hills. Taoli islet is only nest area in the plain. The 20% nest sites continued 60 years to 100 years already, different from those new sites in the lower reaches of the Yalu River.By the end of summer of 2016, 4 former breeding sites disappeared. Total nest numbers was 10 731, mean number of nests in a nest tree was 2.45, the mean of nest height was 9.45 m, and mean diameter of the nest tree was 20.8 cm in 2016. Nesting trees belonged to natural secondary forest, including Quercus spp., Robinia pseudoacacia, Juglans mandshurica; and planted forests, including larix spp., Pinus korainensis, Abies holophylla and Populus spp. Larix olgensis was the most familiar species in all nest areas. The 2 500 nests,the maximum was found in Eastern double hills in Majiadian town in Donggang city. The maximum and minimum areas of nests were found in Donggang and Fengcheng city. The maximum numbers of nests were25 found in Robinia pseudoacacia trees in Old oil depot in Qianyang town. Rough trees were with more nests and higher nest height. Diversity of egrets was greater in seashore plain than that in north hills. Nest height(14.6 m) and diameter of nest trees(30.8 cm) in north hills were greater than those in south coastal plain with lower nest height(7.84 m) and less diameter of trees(17.7 cm). Great egret was the specie between northern mountains and southern coastal hills, but grey herons occasionally came to southern coastal hills for nesting.Usually grey herons prefer to river surroundings, come to breed earlier and cluster in Qingming festival.Egrets gathered for southward migration in mid-August in the wetlands of the nest area. Since 2004, the distribution of nest area has been widened, especially from 2004 to 2005; numbers of breeding egrets increased. Comparing the two periods; from 2004 to 2005 and from 2010 to 2012, the maximum of increasing rate occurred from 2010 to 2012. However the rise was getting pretty little after 2012. Coastal plain was the main expansion area for nesting. Nest area disappeared mostly caused by the death of the trees, disturbance of human being, and re-selecting breeding sites. Avoiding human disturbance was the most important measure to stabilize nest area, and as well much larger protected area should be expended, therefore more breeding sites could be selected. For implementing the regional ecological tourism, distribution of breeding herons should be found out on a larger scale, topographical and ecological factors should be defined to the selection of the nest sites, and productivity of population should also be estimated.
引文
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[2]James A K. Sympatric foraging of little egrets and snowy egrets in Barbados of West Indies[J]. Water Birds, 2007, 3030(4):609-612.
[3]朱曦.中国鹭科鸟类研究进[J].林业科学, 2005, 4141(1):174-180.
[4]高明.鸭绿江下游鸟类资源与生态保护研究[D].长春:东北师范大学城市与环境学院, 2011:35-40.
[5]高明,殷秀琴,王旭.鸭绿江下游鹭类集群繁殖地新发现[J].辽宁林业科技, 2010,(3):32-32.
[6]吴逸群.我国鹭类的生物学研究进展[J].湖北农业科学, 2012,5151(5):879-882.
[7]约翰马敬能,卡伦菲利普斯,何芬奇.中国鸟类野外手册[M].长沙:湖南教育出版社, 2000:210-217.
[8]傅沛云.东北植物检索表[M].北京:科学出版社, 1995.
[9]Sutherland W J. Ecological Census Techniques[M]. Cambridge,United Kingdom:Cambridge University Press, 1996.
[10]赵光复,李国强.鸭绿江鱼类志[M].长春:吉林文史出版社,2008:1-9.
[11]邓福英.广西沿海地区鹭类对植物群落的影响[D].南宁:广西大学林学院, 2004.
[12]朱曦.浙江鹭类资源现状及其保护对策[J].动物学杂志, 2001,3636(4):37-40.
[13]陈辉,高智晟,崔守斌,等.黑龙江七星河国家级自然保护区白琵鹭巢区配置研究[J].湿地科学, 2014, 1212(2):192-196.
[2]James A K. Sympatric foraging of little egrets and snowy egrets in Barbados of West Indies[J]. Water Birds, 2007, 3030(4):609-612.
[3]朱曦.中国鹭科鸟类研究进[J].林业科学, 2005, 4141(1):174-180.
[4]高明.鸭绿江下游鸟类资源与生态保护研究[D].长春:东北师范大学城市与环境学院, 2011:35-40.
[5]高明,殷秀琴,王旭.鸭绿江下游鹭类集群繁殖地新发现[J].辽宁林业科技, 2010,(3):32-32.
[6]吴逸群.我国鹭类的生物学研究进展[J].湖北农业科学, 2012,5151(5):879-882.
[7]约翰马敬能,卡伦菲利普斯,何芬奇.中国鸟类野外手册[M].长沙:湖南教育出版社, 2000:210-217.
[8]傅沛云.东北植物检索表[M].北京:科学出版社, 1995.
[9]Sutherland W J. Ecological Census Techniques[M]. Cambridge,United Kingdom:Cambridge University Press, 1996.
[10]赵光复,李国强.鸭绿江鱼类志[M].长春:吉林文史出版社,2008:1-9.
[11]邓福英.广西沿海地区鹭类对植物群落的影响[D].南宁:广西大学林学院, 2004.
[12]朱曦.浙江鹭类资源现状及其保护对策[J].动物学杂志, 2001,3636(4):37-40.
[13]陈辉,高智晟,崔守斌,等.黑龙江七星河国家级自然保护区白琵鹭巢区配置研究[J].湿地科学, 2014, 1212(2):192-196.