贵州地区黑线姬鼠种群繁殖特征

黑线姬鼠(Apodemus agrarius)是贵州地区分布广泛的主要农田害鼠之一,掌握其种群繁殖特征可为种群动态的预测预报提供基础资料。1984~2014年间,采用夹夜法逐月调查了贵州省余庆县8个县(市)监测点黑线姬鼠种群动态数据,分析了其种群性比、雌鼠怀孕率和平均胎仔数、雄鼠睾丸下降率等主要繁殖生物学指标及其地理差异和季节性变动规律,明确了贵州地区黑线姬鼠种群的繁殖特征。共捕获黑线姬鼠20 113只,不同地区种群间,除平均胎仔数有显著差异外(χ~2=36.503,df=7,P0.01),其他繁殖特征值均没有差异。从时间序列看,种群中雌鼠怀孕率和雄鼠睾丸下降率的季节性变化均表现为春季(4~5月)及夏末秋初(8~9月)达到高峰的双峰型。雌鼠产仔数一般2~10只,4~7只最为常见(占93.87%)。不同季节平均胎仔数差异不大。贵州地区黑线姬鼠繁殖的总体特点为全年繁殖,春秋两季为繁殖的高峰期,冬季(12月份和翌年1、2月份)繁殖强度明显低于其他季节(F_(11,84)=61.92,P0.01),但种群密度表现为6月达到最高点的单峰型特点。     

黑线姬鼠(Apodemus agrarius)的种群繁殖参数及其地理分异特征

黑线姬鼠（Apodemus agrarius）是我国广大地区的主要害鼠之一,是余庆县农田害鼠优势种,占总鼠数的94.81%。探讨其种群繁殖参数的变动规律及其地理分异特征,对其种群数量预测预报具有重要意义。通过对1987-2005年贵州省余庆县黑线姬鼠种群繁殖参数分析结果表明：研究期间共解剖标本5497只,其中,雌鼠2698只,雄鼠2799只,黑线姬鼠在当地1-11月份均可繁殖,主要繁殖期在3-10月份,每年4-5月份和8-9月份出现2次妊娠高峰。种群总性比（♀/♂）为0.96,多年平均怀孕率为36.91%±6.79%,平均胎仔数为5.33±1.07只,平均繁殖指数为0.81±0.17,平均睾丸下降率为59.13%±7.89%。不同年龄组种群繁殖力存在显著差异,随着种群年龄的增长繁殖力不断增加,成年Ⅰ组、成年Ⅱ组、老年组是种群繁殖的主体。种群繁殖参数不同年度之间比较稳定,不同月份、不同季节之间变化差异较大,具有明显的季节变化特征。年均种群密度与年均繁殖指数呈极显著正相关,与胎仔数显著正相关,与年均怀孕率、睾丸下降率、性比相关性不显著,繁殖指数是影响黑线姬鼠种群密度的重要因子。比较全国各地黑线姬鼠种群繁殖参数的地理分异特征认为,黑线姬鼠种群繁殖参数具有明显的地理分异现象,胎仔数、生殖强度由南向北逐渐增加,具有随纬度的升高趋向增加的特征;在高纬度地区繁殖时间较短;性比与纬度、经度的变化关系密切;各繁殖参数与海拔的变化相关性不明显,可排除海拔因素的影响。     

典型草原区达乌尔鼠兔繁殖生态学的初步研究

达乌尔鼠兔是我国典型草原区的主要鼠种之一,对其繁殖特征知之甚少。作者于2009年7-11月和2010年4-9月在内蒙古典型草原区采用整洞群夹捕的取样方法捕获了199只达乌尔鼠兔(Ochotona dauurica),对其种群数量、性比、繁殖特征和年龄结构进行了研究。结果显示：2009年鼠兔数量118只,2010年81只;雌鼠数量显著多于雄鼠;达乌尔鼠兔的繁殖期为3-9月,高峰期集中在4-6月份,平均胎仔数为6.15±0.50(n=13);2009年的7-9月幼年和亚成年比例均小于50%,成年个体成为种群的重要成分;2010年幼体主要集中在5-7月份,且6月和7月幼体和亚成体的数量超过了成年鼠兔的数量,8-9月份种群的主要成员为亚成年和成年鼠兔。达乌尔鼠兔种群繁殖特征是对草原环境适应的体现。     

用逐步回归法建立鼠类数量预测模型的探讨——以江西安义县的黑线姬鼠为例

黑线姬鼠(Apodemus agrarius)是我国广大农区的重要野栖害鼠,有关该鼠的种群数量预测预报国内外研究甚少。本文以江西省安义县的黑线姬鼠为例,应用逐步回归分析法对影响该鼠种群数量变动的因素进行筛选,探讨建立鼠类种群数量预测模型,经回报和试报检验,效果尚好,兹报道如下。 影响黑线姬鼠种群数量变动的因素比较多,我们以鼠类生物学和生态学为基础,结合前人的研究结果,初选出16个入选因子,然后将这些因子输入计算机进行筛选。这16个入选因子是:X_1:怀孕率;X_2:平均胎仔数;X_3:繁殖指数;X_4:成体性比;X_5:总性比;X_6:雄性成体百分比;X_7:雌性成体百分比;X_8:雄性成老体百分比;X_9:雌性成老体百分比;X_10:雄性成老体比;X_11:雌性成老体比;X_12:总成老体比;X_13:雌性成体比;X_14:总成体比;X_15:月平均气温;X_16:月降雨量。     

针毛鼠的形态及其种群生态特征

为丰富针毛鼠种群生态学资料,给其测报及防治提供依据。对贵州省余庆县、岑巩县、雷山县、凯里市1984~2013年针毛鼠的形态及其种群生态特征统计分析,结果表明:雌、雄鼠形态特征无显著性差异。该鼠主要栖息于旱地耕作区,占总鼠数的3.84%,平均捕获率为0.19%。不同年度之间种群数量存在明显差异,全年种群数量在5月和10月出现2个数量高峰,平均捕获率均为0.27%,春季、夏季和秋季种群数量明显高于冬季。种群总性比为0.82,平均怀孕率为27.92%,平均胎仔数为5.12只,平均子宫斑数为5.36只,平均睾丸下降率为59.89%,平均繁殖指数为0.65。3~9月为主要繁殖期,其间在3~4月和7~8月出现2个种群繁殖高峰,春季和夏季为主要繁殖季节。每年4月和8月是防治该鼠的最佳时期,防治重点区域为旱地耕作区。     

上海奉贤区农田鼠类种群数量变动以及气候和耕作因素的影响

分析了上海奉贤区1988—2013年鼠类种群数量变动及年际变化,探讨了鼠类种群动态与气候、生态因子的相关性.结果表明:1988—2013年平均鼠密度为1.3%,优势种是黑线姬鼠,年代间变动不大,平均构成比为97.5%.鼠密度高峰期出现在2—5月,3月最高,年平均鼠密度及峰值随年代呈明显的下降趋势;鼠类成1体与年序呈显著正相关,成2体和老年体与年序呈显著负相关,鼠龄随年代发展有缩短的变化趋势;气温因子除1月平均气温与鼠密度呈弱的正相关外,大多为负相关,2月出现极端暖事件对鼠密度有滞后正效应;降水因子与鼠密度相关性不显著;相对湿度因子与鼠密度大多呈正相关;以粮食播种面积减少为主的种植结构调整与鼠密度及其逐年下降变化存在显著相关性;灭鼠率不断提高与鼠密度的下降也存在相关性.     

呼和浩特地区黑线仓鼠种群动态研究

1984—1989年,每年3—11月中旬在呼和浩特郊区定点调查,共捕获黑线仓鼠2920只,本文分析了该鼠每年的种群数量变动和年龄结构,用臼齿咀嚼面磨损程度划分年龄组,研究种群年龄结构。种群数量年际变化较大,季节变化也较明显,一般年有两个繁殖高峰和数量高峰(后峰8—10月,前峰5—6月)。每年3—10月为繁殖期,平均每胎产仔6.2±0.1只,各年间繁殖有一定差异。     

北京顺义区农田两大害鼠种群繁殖力比较

为了揭示顺义农田黑线姬鼠和大仓鼠两大害鼠种群繁殖力存在的差异及其对种群数量变化的影响,从而为制定科学灭鼠策略提供依据,1994-2014年,采用夹线法于每年3~11月(或1~12月)进行调查,每月上旬在5个监测点农田布放鼠夹500夹夜。捕获的样本测量体重、体长、尾长、耳高、后足长,解剖观察繁殖情况。以种群繁殖力为指标,分析黑线姬鼠与大仓鼠在繁殖力方面的差异,由此揭示出黑线姬鼠具有更强的竞争优势。黑线姬鼠和大仓鼠每年都有2个繁殖高峰期,并以成年以上个体为繁殖主体,分别占总胎仔数的94.5%和95.6%。黑线姬鼠的繁殖期和主要繁殖期均比大仓鼠延长1个月,且主要繁殖期的雌、雄繁殖鼠占比均高于大仓鼠,胎次数是大仓鼠的1.7倍,仅平均胎仔数低于大仓鼠,由此说明黑线姬鼠种群的繁殖力比大仓鼠更强,具有更大的竞争优势。     

气候因素对黑线姬鼠种群动态影响的非线性效应

受全球气候变化的影响,气候因素与害鼠种群变化之间的关系成为害鼠防治研究中的热点问题。以西安市长安区周边分布的黑线姬鼠为研究对象,通过标志重捕法进行种群动态监测,掌握其种群数量的动态变化规律,并结合非线性的统计方法广义可加模型,对该地区2015—2018年黑线姬鼠种群密度和气候因素数据进行分析,探讨该鼠种群变化与气候因素之间的关系。结果表明,该地区黑线姬鼠种群数量总体显现为下降趋势。黑线姬鼠种群密度存在显著的正向自我调节效应(F_(1.00, 5.77)=27.062,P0.01),且与上一月种群密度存在线性的正相关。当月平均温度与该鼠种群密度之间存在显著的非线性效应(F_(1.90, 5.77 )=4.696,P0.05),两者之间显现为钟型关系,当温度21℃时,两者之间显现为正相关,黑线姬鼠种群密度随温度的升高而升高,反之显现为负相关。当月累计降雨量与其种群密度之间也存在显著的非线性效应(F_(1.87, 5.77)=3.879,P0.05),同样,两者之间也显现为钟型关系,当降雨量90 mm时,两者之间显现为负相关,种群密度随降雨量的增加而降低,反之显现为正相关。因此,温度和降雨对黑线姬鼠种群变化具有调节作用,低温干旱和高温多雨均不适合该鼠的繁殖与生长。     

布氏田鼠种群年龄的研究

啮齿动物在草原中的作用,主要决定于它的数量。鼠类数量的预测预报,往往是草原建设中所重视的问题。在各种害鼠的预测方案中,都要研究它们的种群年龄组成,研究不同年龄组的年度和季节变化,进一步研究繁殖,种群密度等,然后分析种群数量变动规律,进行鼠害的预测预报,以指导灭鼠工作。     

Strong “bottom‐up” influences on small mammal populations: State‐space model analyses from long‐term studies

“Bottom‐up” influences, that is, masting, plus population density and climate, commonly influence woodland rodent demography. However, “top‐down” influences (predation) also intervene. Here, we assess the impacts of masting, climate, and density on rodent populations placed in the context of what is known about “top‐down” influences. To explain between‐year variations in bank vole Myodes glareolus and wood mouse Apodemus sylvaticus population demography, we applied a state‐space model to 33 years of catch‐mark‐release live‐trapping, winter temperature, and precise mast‐collection data. Experimental mast additions aided interpretation. Rodent numbers in European ash Fraxinus excelsior woodland were estimated (May/June, November/December). December–March mean minimum daily temperature represented winter severity. Total marked adult mice/voles (and juveniles in May/June) provided density indices validated against a model‐generated population estimate; this allowed estimation of the structure of a time‐series model and the demographic impacts of the climatic/biological variables. During two winters of insignificant fruit‐fall, 6.79 g/m² sterilized ash seed (as fruit) was distributed over an equivalent woodland similarly live‐trapped. September–March fruit‐fall strongly increased bank vole spring reproductive rate and winter and summer population growth rates; colder winters weakly reduced winter population growth. September–March fruit‐fall and warmer winters marginally increased wood mouse spring reproductive rate and September–December fruit‐fall weakly elevated summer population growth. Density dependence significantly reduced both species' population growth. Fruit‐fall impacts on demography still appeared after a year. Experimental ash fruit addition confirmed its positive influence on bank vole winter population growth with probable moderation by colder temperatures. The models show the strong impact of masting as a “bottom‐up” influence on rodent demography, emphasizing independent masting and weather influences; delayed effects of masting; and the importance of density dependence and its interaction with masting. We conclude that these rodents show strong “bottom‐up” and density‐dependent influences on demography moderated by winter temperature. “Top‐down” influences appear weak and need further investigation.     

卡氏小鼠种群数量变动特征及其与环境因子的关系

本文报道卡氏大鼠种群数量变动特征及其与环境因子的关系,种群数量年间变动较大,季节较化一般出现２个高峰。分别在５－６月和１１月,与农作物的成熟,收获以及小鼠繁殖活动有关,１月份的种群数量多及２、３月份的平均气温高低,对当年５月份种群数量有密切关系。本文提出了３个回归方程式,可初步估计当年５月的种群数量。     

A mitogenome of the Chevrier's field mouse (Apodemus chevrieri) and genetic variations inferred from the cytochrome b gene

The Chevrier's field mouse (Apodemus chevrieri) is an endemic species to China and is an important pest in agriculture and human diseases. In this study, the complete mitochondrial genome of this species was sequenced and its size was 16,298 bases (accession no.: HQ896683). The mitogenome structure was similar compared with other reported rodent mitochondrial genomes and includes 13 protein-coding genes, 2 rRNA genes (12S rRNA and 16S rRNA), 22 tRNA genes, and 1 control region. This was the first complete mitogenome sequenced in genus Apodemus. The phylogenetic analyses based on the sequences of 12 heavy-strand protein-coding genes demonstrated that A. chevrieri clustered together with genus Mus. Additionally, extremely high haplotype and nucleotide diversities (h=0.978, π=2.6%) were observed based on 44 mitochondrial cytochrome b (cyt b) gene sequences. This suggests adaptive divergence of this species to a variety of living habitats and potential refuges in the eastern margin of the Hengduan Mountains during the Quaternary ice ages. No population expansions or genetic bottlenecks were observed in demographic analyses. The phylogenetic analysis of cyt b sequences and haplotypes revealed a genetic differentiation between north and south populations. The divergence between north clade and south clade occurred probably in the middle Pleistocene 1.1815 million years ago (Mya) (95% highest posterior density 2.3189-0.2737 Mya), which was congruent with the periods of the most tense uplift events in the Tibetan Plateau.     

Demography and population dynamics of the mouse opossum (Thylamys elegans) in semi-arid Chile: seasonality, feedback structure and climate

Here we present, to the authors' knowledge for the very first time for a small marsupial, a thorough analysis of the demography and population dynamics of the mouse opossum (Thylamys elegans) in western South America. We test the relative importance of feedback structure and climatic factors (rainfall and the Southern Oscillation Index) in explaining the temporal variation in the demography of the mouse opossum. The demographic information was incorporated into a stage-structured population dynamics model and the model's predictions were compared with observed patterns. The mouse opossum's capture rates showed seasonal (within-year) and between-year variability, with individuals having higher capture rates during late summer and autumn and lower capture rates during winter and spring. There was also a strong between-year effect on capture probabilities. The reproductive (the fraction of reproductively active individuals) and recruitment rates showed a clear seasonal and a between-year pattern of variation with the peak of reproductive activity occuring during winter and early spring. In addition, the fraction of reproductive individuals was positively related to annual rainfall, while population density and annual rainfall positively influenced the recruitment rate. The survival rates were negatively related to annual rainfall. The average finite population growth rate during the study period was estimated to be 1.011 +/- 0.0019 from capture-recapture estimates. While the annual growth rate estimated from the seasonal linear matrix models was 1.026, the subadult and adult survival and maturation rates represent between 54% (winter) and 81% (summer) of the impact on the annual growth rate.     

横断山区高山姬鼠身体能值的适应性调节

为探讨栖息于横断山地区高山姬鼠(Apodemus cheurieri)身体状况与环境之间的适应关系,对野外和实验室条件下高山姬鼠的身体能值进行了测定.结果表明,高山姬鼠身体能值存在季节性变化,6月最高,9月次之,11月开始下降,到次年3月达到最低.冷驯化条件下,其身体能值显著降低.高山姬鼠的身体能值在不同季节和冷驯化条件下表现出的变化模式,与其低纬度高海拔、年平均温度较低的生存环境有关.反映了横断山区小型哺乳动物在季节性环境中的生存机制和适应对策.     

Surviving north of the natural range: the importance of density independence in determining population size

The relative importance of density-dependent and -independent processes in determining population density has been predicted to vary according to whether the population concerned is located near the centre or the periphery of the species' range. Thus, density-independent processes should be more pronounced near the periphery. The long-tailed wood mouse Apodemus sylvaticus in Iceland is at the northern and western edge of its geographical range. We estimated the autumn population density in an open habitat in south-western Iceland in 9 years out of 10 during 1996–2005 in order to monitor the annual maximum population size. Furthermore, we estimated population density and survival at c . 5-week intervals from September 2001 to October 2003 and from September 2004 to November 2005 in order to reveal the causes of variation in maximum population size. The estimated autumn population density was low, ranging from 2.7 to 8.9 mice ha⁻¹ while spring densities ranged from 0.4 to 0.8 mice ha⁻¹. Apparent monthly survival probabilities ranged from 0.4 to 0.7 per month in autumn and 0.7 to 0.9 in winter. Our results suggest that low temperature in early winter (October–December) is the major determinant of population density in the following autumn, explaining 74% of the variation in autumn population density. No significant correlation was found between either the NAO index or the NAO winter index and variation in wood mouse population density in autumn. Differential mortality in early winter results in variation in spring population size. This study shows clear evidence of density-independent control of a mammal population at the edge of its geographical range as opposed to the mostly density-dependent control previously recorded near its centre of distribution.     

云南老君山鼠类的垂直分布

1980年6月至8月,我们对云南老君山的鼠类进行了垂直分布的调查研究。现介绍如下。 自然概况 老君山位于云南省的剑川、丽江和兰坪三县交界处;北纬26°30′—26°52′,东经99°42′—100°26′。属于著名的横断山脉的云岭山系中的大山之一。最高峰海拔4,247m.,山麓(金坪)海拔2,500m.。山势南北走向,北高南低,有纵横交错的高山、山间峡     

Spatiotemporal variation in predispersal seed predation intensity

The effect of predispersal seed predation by Bruchus atomarius (Bruchidae, Coleoptera) on individual performance and population dynamics of the perennial forest herb, Lathyrus vernus (Leguminosae), was investigated in 11 permanent plots over 4 years. Seed predation and parameters describing intra-specific neighbour distance, plant size, inflorescence size, flowering phenology and current and previous herbivore damage were measured on all plants. In addition, demographic information from all plots was analysed using transition matrix population models in order to estimate the influence of seed predation on population growth rates. Predispersal seed predation rates differed significantly among years. Plot averages ranged from 0 to 83.7%. However, most of the variation occurred among individuals. Within individuals there was no consistency in predation rates among years. Exposure to herbivory, plant size and flowering phenology did not affect predation rates but individuals with larger inflorescences suffered from significantly higher predation. Seed predation in L. vernus was not influenced by neighbour distances of individual plants but it was positively correlated with the average density of seeds within plots, suggesting that seed predation is density dependent at the patch level. The reduction in population growth rate due to seed predation ranged from 0 to 7.6%. The sensitivity of population growth rate to reductions in seed production varied considerably among years and plots. This variation was mainly due to differences in the reproductive value of seeds and seedlings. The intensity of seed predation over the range found was not correlated with changes in population growth rate. The results of this study suggest that the influence of external factors, like seed predation, on population growth rate largely depends on the demographic transition rates in the investigated population.     

Meteorological effects on adult mosquito (Culex) populations in metropolitan New Jersey

For two metropolitan New Jersey counties, monthly average adult mosquito (Culex) catch from New Jersey light trap data sets covering multiple decades is related to a number of meteorological factors. From June through August climatological conditions accounted for between 40% and 50% of the variation in average catch. In general, high monthly precipitation totals both in the month corresponding to the catch and the previous month were associated with increased trap catch. However, individual heavy rainfall events tended to reduce catch. Warm temperatures exerted a positive influence on mosquito abundance in June, but were associated with a low catch in August. Linear meteorological relationships explained only a small percentage of the variations in mosquito catch during May and September. During July, and particularly August, antecedent monthly catch also explained a significant portion of the variance in the contemporaneous catch. Over 60% of the variability in August catch could be attributed to the July population.