自然条件下不同出生期布氏田鼠寿命的研究

1994－08～1996－10对内蒙古太仆寺旗不同出生期376只布氏四鼠幼鼠的标志跟踪,编制了动态寿命表。以此探讨了该鼠种群不同出生期的期望寿命（ex）及其在种群更替中的作用。结果表明,该鼠平均ex为4．09个月,最长存活期为13个月。春季繁殖的第1窝鼠平均ex为5．11个月;当其长到20g时即可参加繁殖,这窝鼠有89．6％的个体在翌年春季前死亡;越冬个体在翌年仍可繁殖1次。夏季出生的第2窝鼠ex为3．56个月,其中有20．8％的个体越冬,在翌年春季与第3窝鼠同为主要繁殖力量。夏末出生的第3窝鼠ex为4．48个月,当年不参加繁殖,27％～39％个体可越冬并参加翌年繁殖,可连续繁殖2窝。     

多代驯化对布氏田鼠非繁殖期性激素本底水平的影响

为阐明驯化过程对季节性繁殖的布氏田鼠Lasiopodomys brandtii性腺活性的影响,采用放射免疫技术从秋季(11月)至翌年春季(3月)对室内驯化1月、3年和10年的雌雄鼠粪便中的性激素水平进行监测.结果 显示,在11-12月非繁殖季节,驯化10年组雄鼠睾酮水平分别达到3年组和1月组的3.5倍和13.3倍,驯化...     

伊犁田鼠夏季生境选择的主导因子分析

1998年5～6月。在新疆新源县纳孜确鹿特山地草甸类草地自然保护区对伊犁田鼠的生态学进行了调查研究。以伊犁田鼠铗捕率为因变量．以高度、盖度、植物种数等8种生境因子为自变量进行逐步回归分析．结果表明．伊犁田鼠夏季生境选择主导因素为：草群高度、盖度、产草量(正相关)。鼠种数(负相关)，复相关系数R=0．9959，F=389．92，为极显著相关。     

Trapping for mink control and water vole survival: Identifying key criteria using a spatially explicit individual based model

Introduced alien species are the second most important threat to global biodiversity after habitat loss. The American mink Mustela vison has been introduced to several countries and is threatening a number of native species worldwide. We developed a spatially explicit and individual based model as a planning tool to identify key criteria for the implementation of trapping campaigns as a way to control open American mink populations. We first predicted the minimum effort required to reduce populations of mink below a certain threshold and the best time of year in which to trap mink to minimise their numbers. We then employed this methodology to predict the best trapping strategy to ensure the long-term survival of the water vole Arvicola terrestris, one of the species most endangered by the spread of the mink in the UK. We also applied the mink and water vole population models to rationalise a set of observed data in an area of 50 × 30 km in the Upper Thames (UK). The model predicted that it is necessary to remove mink for at least 3 months every year and that a mixed strategy of trapping during the mating, late dispersal and winter seasons is best for keeping mink at low densities. Concentrating trapping during the late dispersal and winter seasons is instead best for ensuring the long-term survival of water voles. Targeting immigrating juvenile mink as well as reproductive adults is important. The model also showed that trapping efficiency might be an important factor to consider when choosing periods in which to trap.     

Development of transferred xenogeneic vole embryos in mouse uteri

An experimental model to study interspecific pregnancy using voles, Microtus arvalis, and green fluorescent protein gene‐induced transgenic mice is presented. Xenogeneic blastocysts from the vole were transferred into the uteri of pseudopregnant mice along with allogeneic blastocysts from green fluorescent protein gene‐induced transgenic mice. The uteri containing xeno‐allo combined transfers were examined from day 6 to 13 of gestation. Although the vole embryos implanted, the uteri containing vole embryos were smaller compared with those having allogeneic mouse embryos. On day 8, the uteri containing vole embryos hemorrhaged internally and no vole embryo was found in the pregnant uterus after day 11. Allogeneic mouse embryos developed normally despite the presence and abortion of the vole embryos. In uteri implanted with vole embryos, decidua were formed and numerous blood vessels were distributed around the embryo. Maternal blood cells infiltrated into the celomic cavity of the vole embryo through the discontinuous region of trophoblast. Periodic acid‐Schiff‐positive granulated metrial gland cells were remarkably increased in the decidual sites. These findings suggest that a disorder of embryo–maternal interaction might induce the appearance of numerous granulated metrial gland cells and rejection of the embryos.     

Relationship between resistance to vole browsing and content of ether extract in the bark of larch species and hybrids

We determined the survival rate of tree families produced by the intra- and interspecific crossing of larch species damaged by browsing of vole (Clethrionomys rufocanus bedfordiae Thomas) and the contents of ether extracts (EE) in their bark. The average survival ofLarix gmelini var.japonica Pilg. (L. gmelini)×L. gmelini (G×G) was highest, followed by the hybridL. gmelini×L. leptolepis Gordon (G×L). The families of the hybrid G×L, which is considered suitable for silviculture in Hokkaido, Japan, showed significant differences in survival rates, suggesting that it is possible to produce improved varieties of the hybrid which are more resistant to vole browsing. The EE contents of the bark were under strong hereditary control, and the rank of the EE content among the various families hardly fluctuated between the location of the test fields. The correlation coefficient between the survival rates and the EE contents was highly significant (r=0.89,n=24,p<0.01), indicating that the EE content in the bark may be used as a possible index of resistance or susceptibility to vole browsing in larch plantations. A part of this report was presented at the 106th Annual Meeting of the Japanese Forestry Society, at Sapporo, April, 1995.     

American mink control on inland rivers in southern England: An experimental test of a model strategy

Invasive species are an important driver of global biodiversity loss. Under international legislation, the UK has an obligation to eradicate or to control the alien, invasive American mink. Using a large-scale field experiment, we tested the effectiveness of a specified mink removal strategy, identified through earlier modelling work, in reducing the relative abundance of mink. We found that mink removal could be effective in reducing mink populations with four months or less of trapping per year, over only 2-3 years, but that for small sites (c. 20 km) a flexible, reactive approach, coupled with continual monitoring for mink presence is necessary. Survival of reintroduced water voles at four sub-sites within our mink removal sites suggest that the reactive mink removal strategy adopted in this study was sufficient for water vole protection. We discuss the use of an adaptive management approach in local mink management, and consider the wider implications of our results for invasive species control on mainlands.     

Comparative efficacy of conventional and new rodenticides against Microtus arvalis (Pallas, 1778) in wheat and alfalfa crops

In order to compare the efficacies of new rodenticides (sodium selenite and cellulose) and conventional ones (bromadiolone, brodifacoum and cholecalciferol) in controlling Microtus arvalis (Pallas, 1778) in wheat and alfalfa crops, experiments were conducted at two sites near Belgrade, Serbia, in the spring of 2008, using a standard EPPO method. The presence of rodent populations, their spatial distribution and density indexes were evaluated by pre-treatment census, and rodenticide efficacy by counting active holes 14 and 28 days after treatment.     

黑龙江省张广才岭林区棕背(鼠平)种群主要参数分析

在黑龙江省张广才岭海林林区,采用铗捕法逐月捕获棕背(鼠平),根据胴体重和繁殖情况划分棕背(鼠平)的年龄(以月为单位),计算各月新生个体的生命表、各月种群平均年龄和平均寿命.共捕棕背682只,其中雌性351只,雄性331只,雌雄性比为0.515: 0.485.5,6,7月出生的个体最长寿命为5个月,雌性平均为2.37个月,雄性平均为2.18个月.8,9月出生的个体,最长寿命超过12个月,雌性平均为3.83个月,雄性平均为4.03个月.秋生个体比春生个体寿命长.各月种群平均寿命4月份最高,为10.52个月,7月份最低,为2.94个月.     

用头骨上齿隙鉴定布氏田鼠种群年龄的研究

本文在笔者前期工作的基础上，根据布氏田鼠15项生长指标的主分量分析结果，筛选出以头骨上齿隙作为划分布氏田鼠相对年龄组客观而简便实用的指标。该鼠的头骨上齿隙没有性别差异，对雌雄鼠可采用同一标准同时划分其年龄组。通过进一步分析，将其划分为五个年龄组：幼年组的上齿隙在6．49mm以下，亚成年组为6．50～7．33mm，成年一组为7．34～838mm，成年二组为8．39～9．43mm，老年组在9．44mm以上。此外，本文尚就年龄组成及其季节变化、年龄与繁殖等方面进行了分析。