埃塞俄比亚Senkele Swayne保护区斯韦恩麇羚的种群现状与结构

于2005年10月至2006年4月调查了埃塞俄比亚森可勒斯韦恩麇羚保护区旱季和湿季斯韦恩麋羚（Alcelaphus buselaphus swaynei）的种群现状与结构。根据植被类型、道路和沟谷,将研究区划分为5个区域,并且调查了保护区外的一块休耕农地。利用全部计数法计数了每个区域内的斯韦恩麋羚,在28km^2的区域内共统计到283只（湿季）和351只（旱季）麋羚,湿季和旱季的糜羚数量变化显著,其季节间差异是由旱季的出生高峰造成的。斯韦恩糜羚种群中雌性个体占42．7％、雄性占36．0％、幼羚占21．3％。某些区域的麋羚数量要高于其它区域,且无论湿季或旱季斯韦恩麋羚多集中在狼尾草高草地中。斯韦恩麋羚的种群结构随季节而变化,其大集群经常出现在湿季而旱季集群较小。斯韦恩麇羚的种群动态因保护程度的不同在不同时期呈不规则性变化     

内蒙古贺兰山冬春季岩羊种群现状及保护

为调查内蒙古贺兰山国家级自然保护区内岩羊（Pseudois nayaur alashanicus）的种群现状,通过样线法在2017、2018年冬季,2018、2019年春季进行了调查,利用R 4.0.3中的Distance 1.0.2对样线观测数据进行分析,估测保护区内岩羊的种群数量及密度,分析其种群结构。结果显示,调查共观测到岩羊6299只,其中,2018年冬季种群数量最高,约为2654（2230-3161）只（括号内为95%数量置信区间）,种群密度为3.921（3.293-4.668）只/km²。与2003年同季节的调查数据对比发现,保护区内岩羊的种群数量在15年间增长迅速,岩羊的种群密度累计增长了约53.17%,年平均增长3.54%。岩羊集群形式：混合群（88.03%,80.95%）为岩羊冬、春最主要的集群形式,且混合群的数量冬季多于春季,独羊出现的次数最低（1.99%,2.86%）,不同的集群类型在不同的季节的差异极显著（P<0.001）;岩羊平均群大小：春季为（13.439±12.085）只,冬季为（9.011±8.610）只,调查季节中集群大小多为1-10只,岩羊的不同季节的群大小差异极显著（P<0.001）。种群成体与幼体比在不同季节的变化范围为1.411-2.673,雌雄比在不同季节的变化范围为0.934-1.469,种群结构的季节性差异极显著（P<0.001）。集群类型、群大小及群组成的调查表明,不同季节间岩羊种群结构差异明显。     

宁夏贺兰山国家级自然保护区岩羊(Pseudois nayaur)种群数量及结构

为了解宁夏贺兰山岩羊的种群现状,2020-2021年的8月和12-1月,在宁夏贺兰山国家级自然保护区运用样线法对岩羊（Pseudois nayaur）进行种群数量调查,利用R 4.0.1中的Distance 1.0.2对样线观测数据进行分析,估测保护区内岩羊的种群数量及密度,分析其种群结构。结果显示,夏季岩羊种群数量为5176（2554-10490）只,种群密度为2.674（1.320-5.420）只/km²;冬季岩羊种群数量为15752（7294-34017）只,种群密度为8.139（3.769-17.58）只/km²;多数观测距离样线垂直距离在0-200 m之内。岩羊主要集群形式：夏季为雌幼群（52.17%）;冬季为混合群（26.60%）。岩羊平均群大小：夏季为（6.261±8.023）只,冬季为（4.064±4.229）只,群大小在不同季节的差异显著（P=0.010）,集群大小多集中于1-5只之间,最大为47只。夏季调查中,雄性个体占比11.27%,雌性个体占比56.74%,幼体/亚成体占比31.99%;冬季调查中,雄性个体占比29.61%,雌性个体占比50.15%,幼体/亚成体占比20.24%;夏季和冬季岩羊组成成分之间差异极显著（P<0.001）。     

宁夏贺兰山国家级自然保护区马鹿分布及集群特征的初步研究

2009 年1 ～12 月,我们对宁夏贺兰山国家级自然保护区内的马鹿分布情况进行了调查。根据107 个马鹿活动位点和572 个马鹿痕迹位点,分别用95% 的固定核空间法(Fixed kernel estimation,FKE)和100% 的最小凸多边形法(Minimum convex polygon,MCP)进行计算,结果显示保护区内的马鹿分布面积约为642.33 km2 ,占保护区总面积的33 19% ,分布范围介于小水沟和榆树沟之间,插旗口和大水沟是马鹿分布密度最大的两个区域,而人为干扰较严重的黄旗口和小口子在调查过程中没有发现马鹿实体。我们对马鹿在冬季的种群数量进行了调查,利用模型均匀分布和简易多项式级数展开(Uniform + Simple polynomial),Distance 6. 0 的结果显示宁夏贺兰山马鹿的种群数量约为1 420 头(880 ～ 2 300)。保护区内的马鹿在不同的季节有垂直迁移现象,冬季活动在低海拔地区。保护区内的马鹿集群较小(3.50 ± 2.76,1 ～ 13 头,n = 107),且集群大小有季节性差异,冬季(4. 26 ± 3.09)明显大于其它季节。     

山口红树林保护区圆尾蝎鲎种群动态

鲎是珍贵的海洋“活化石”生物。本研究于2014—2020年在广西北海山口红树林生态自然保护区开展圆尾蝎鲎(Carcinoscorpius rotundicauda)种群动态调查。总计观察到圆尾蝎鲎990只,种群数量呈现逐年下降趋势,其中第6个调查年相比第1个调查年下降94.60%,表明圆尾蝎鲎资源保护已势在必行;雄鲎占80.28%,雌鲎占17.50%。圆尾蝎鲎种群动态呈现显著季节规律性,种群数量与温度及北风和南风风向状态值(0和4)呈显著正相关,显示出滨海风向标生物特征。本研究揭示了圆尾蝎鲎种群动态及其影响因素,为保护区鲎资源保护提供参考依据。     

基于样线法和非损伤性标志重捕法对古田山小麂种群现状评价

为分析古田山自然保护区内小麂种群资源的现状,制定合理的保护和管理措施,本研究结合传统的样带调查法和非损伤性标志重捕法进行小麂种群资源的调查与评估。2014年4月、7月、10月和2015年1月在古田山自然保护区内进行了4次调查,结果显示：样带法得到全区的种群密度为(5.8±0.4)只/km²,种群数量为(473.5±29.2)只,其中核心区种群密度最高,为(7.5±0.7)只/km²,种群数量为(160.8±14.0)只;缓冲区为(5.7±0.6)只/km2,种群数量为(98.2±10.4)只;实验区密度最低,为(3.3±0.5)只/km²,种群数量为(140.5±20.7)只。非损伤性标志重捕法得到全区种群密度为(4.9±0.3)只/km²,种群数量为(397±26)只。样带法调查显示,不同功能区之间的种群密度随季节发生变化,核心区、缓冲区和实验区均是春季种群密度最高,保护区内小麂主要栖息在海拔400-800 m之间,夏季向高海拔区域迁移,冬季则向低海拔迁移。SRY性别鉴定结果表明,古田山小麂种群季节间平均雌雄性比1.17∶1,周年雌雄性比为1.11∶1（9只雌性,84只雄性）（x=0.458,P=0.499）,雌性个体的数量优势并不是很明显,若要进一步提高种群数量,则需要加强保护。     

广东海丰鸟类自然保护区黑脸琵鹭越冬种群现状

黑脸琵鹭(Platalea minor)是全球性濒危鸟类,广东海丰鸟类自然保护区作为新发现的重要越冬地,具有全球保护意义.2004~2007年对保护区内黑脸琵鹭越冬种群的调查结果表明,该越冬种群数量逐年增加(27~72只),占全球总数比例也相应增加(2.2%~4.1%).其主要分布在红树林、沿海滩涂和人工养殖塘3种生境,其中,沿海滩涂累计记录到的个体数最多,达217只;人工养殖塘记录剑最大集群,为52只.需积极采取有效措施保护该越冬种群及其生境.     

广东海丰鸟类自然保护区褐翅鸦鹃数量调查

为掌握褐翅鸦鹃(Centropus sinensis)在广东海丰鸟类自然保护区的种群现状,提出有针对性的保护措施,2005年对保护区内褐翅鸦鹃数量行了调查.4个季节中,夏季记录的个体数最多(32只),其样线平均个体数与春季、秋季相比,差异性显著(P＜0.05);夏季种群密度最大,达17.78只,km2,冬季仅为1.11只/km2.单次记录到的多为单只个体.不同季节在3个保护站记录到的褐翅鸦鹃数量存在一定的差异.总体上,东关联安围记录到的个体数最多.     

青藏铁路沿线藏羚迁徙期集群特征分析

2006年6月、8月和2007年6月、8月,采用样线法对青藏铁路昆仑山至沱沱河区间藏羚(Pantholops hodgsoni)迁徙期集群行为进行了研究。集群类型有雌性群(46.5%)、雄性群(7.4%)、母子群(39.7%)、混合群(1.5%)和独羚(4.8%)5种类型,共计473群,7 828只。不同集群类型出现频次差异极显著(p0.01)。2~20只的集群占72.1%,21~50只集群占17.1%,51~100只集群占4.4%,大于100只集群占1.5%,独羚占4.9%,不同集群大小出现频次差异极显著(p0.01)。迁徙季节藏羚平均群体大小为(16.6±1.06)只(平均值±标准误),雌性群(22.3±3.37)只,雄性群(10.5±1.48)只,母子群(13.1±1.07)只,混合群(11.3±3.51)只,不同集群类型的群体规模差异极显著(p0.01)。藏羚的集群大小与集群类型、迁徙季节密切相关,而集群大小的变化是对青藏铁路运营后新环境的一种适应。     

贺兰山岩羊（Pseudois nayaur）集群特征的季节变化

2004年11月～2005年10月,在贺兰山对岩羊(Pseudois nayaur)的集群行为进行了研究,将其集群类型划分为雌性群、雄性群、雌雄群、母仔群、混合群和独羊6种类型.共观察到岩羊1 023群次,计4 866只次,平均群大小为(4.86±2.54)只,最大的群为51只,最小的为独羊.其中,母仔群459群(44.87%)为最多的集群类型,其余为混合群(20.72%)、雄性群(14.86%)、独羊(9.09%)、雌雄群(5.57%)、雌性群(4.89%).母仔群出现的频次在4个季节均最高,除母仔群外,春季雄性群出现的频次最高,而夏、秋、冬季都是混合群出现的频次最高,不同类型集群出现频次的季节间差异极显著.在4个季节中都以2～5只的群居多,其出现的频次占各季节群数50%以上,不同季节群大小差异极显著,而不同集群类型群大小季节间不存在显著差异.除独羊外,不同季节混合群大小差异极显著,母仔群、雌性群大小差异显著,而雄性群、雌雄群大小无显著差异.研究结果显示,贺兰山岩羊集小群是其显著特点,随着季节的变化,其集群类型、集群大小均会发生一定的变化.     

Population status and structure of mountain nyala in the Bale Mountains National Park, Ethiopia

The study on the population status and structure of mountain nyala (Tragelaphus buxtoni) was carried out in the Bale Mountains National Park, Ethiopia during the wet and dry seasons of 2000/2001. Total counts were carried out in an area of 13.1 km². The count ranged between 682 and 732 individuals. Females comprised 62.9% while males 27.4%. The calf ratio was 9.7%. The group structure of the animals varied with season. Large herds were frequently observed during the wet season and smaller groups during the dry season. Group size changed seasonally. In both seasons, 7–12 individuals were the frequent group size formation. The maximum group (62) was observed during the wet season. The population trend of the animal from 1975 to 1990 indicated a recovery and increase. But between 1990 and 1995 the population showed a continuous and steep decline. However, between 1995 and 2000 the population trend showed a better condition when compared with the previous years.     

Current population estimate and distribution of the African buffalo in Chebera Churchura National Park,Ethiopia

An investigation into the population status and distribution of the African buffalo (Syncerus caffer Sparrman, 1779) in Chebera Churchura National Park, Ethiopia, was carried out during the wet and dry seasons of 2012–2015. This study tested the hypothesis that buffalo would demonstrate seasonal habitat preferences and changes in population density. Sample counts were carried out in an area of 1215 km². The estimated buffalo population was 5193 individuals, with the population density of 4.3/km². The population showed an increase from 2617 to 5194 individuals during 2006–2015. Males comprised 42.6%, while females 46.7% of the population. Age structure was dominated by adults, which constituted 52.5% of the total population. Subadults comprised 24.3% and young 12.4% of the population. Larger herds of up to 30 individuals were observed during the wet season, and smaller herds of a minimum of four individuals were seen during the dry season. The mean herd sizes during the wet and dry seasons were 29.59 and 16.95, respectively. They were observed more in the riverine vegetation types during the dry season. Of the total, 57.6% utilized riverine habitat during the dry season, whereas 39.8% used this habitat during the wet season. Relative abundance of food sources, green vegetation cover and availability of water were the major factors governing their distribution in the present study area.     

Population structure and ecology of the African buffalo (Syncerus caffer Sparrman, 1779) in Chebera Churchura National Park,Ethiopia

An investigation of population structure and ecology of the African buffalo (Syncerus caffer Sparrman, 1779) was carried out in the Chebera Churchura National Park, Ethiopia during the wet and dry seasons of 2005–2006. Sample counts of African buffaloes were carried out in an area of 1,215 km². The estimated population of buffalo was 2,617 individuals. Males comprised 35.0%, while females 52.8% of the population. The remaining 12% of the population was young of both sexes and of all ages of unknown sex. It was difficult to categorize the young into male and female in the field, as their primary sexual characteristics were not easily visible. Male to female sex ratio was 1.00 : 1.51. Age structure was dominated by adults, which constituted 72.06% of the total population. Subadults comprised 22.02%, and young accounted for 5.9% of the population. Larger herds of up to 27 individuals were observed during the wet season and smaller herds of eight individuals during the dry season. The mean herd size during wet and dry seasons was 24.81 and 7.77, respectively. The African buffaloes were distributed in four habitat types such as grasslands, woodlands, montane forests and riverine habitat in the study area. They were observed more in the riverine vegetation types during the dry season. Relative abundance of food resources, green vegetation cover and water availability in the area were the major factors governing their distribution in the present study area. They spent a greater proportion of the time in feeding and resting/ruminating activities. On the average, 49.7% of the daytime was spent in feeding, and 38.75% of the day on resting (lying down and standing). Morning and the late afternoon activity peaks were more pronounced during the dry season than the wet season.     

Diurnal activity budget of African buffalo (Syncerus caffer Sparrman, 1779) in Chebera Churchura National Park,Ethiopia

One of the fundamental questions in animal ecology concerns the activity pattern of animals and the environmental and intrinsic factors that influence such dynamics. This study tested the hypotheses that activity time budgets of the African buffalo appeared to vary by season and times of day and predicted that buffalo would express unequal proportion of time for different activity patterns during the wet and dry seasons in Chebera Churchura National Park (CCNP). An investigation on the diurnal activity budget of the African buffalo was carried out during the wet and dry seasons of 2012–2014 in the Chebera Churchura National Park, Ethiopia, using focal‐animal sampling method. Buffalo spent a greater proportion of the time in feeding and resting/ruminating activities in both the wet and dry seasons. Feeding and resting (lying down and standing) were the predominant activities (87.14% of the diurnal active period), 48.95% time spent feeding during the dry season and 44.91% during the wet season. There was a significant decrease in feeding and an increase in resting from dry seasons to wet seasons. Daytime grazing and resting periods during the wet season were estimated to be 5.39 h and 4.98 h, respectively. Morning and the late afternoon activity peaks were more pronounced during the dry season than the wet season. Therefore, feeding and resting time was influenced by the time of day and the seasons. But there were no significant difference in time allocation for other activities in both the wet and dry seasons. The study has implications for understanding animal activity budget across species, particularly relationships between temperature and season.     

Seasonality in foraging behaviour of Constrictotermes cyphergaster (Termitidae, Nasutitermitinae) in the Caatinga of Northeastern Brazil

The foraging activity of Constrictotermes cyphergaster was investigated in the Caatinga of Northeast Brazil. Eight colonies were monitored for seven days, during both dry and wet seasons. Foraging activity occurred in exposed columns at night, generally between 22:00 and 05:00 h. During the wet season, foraging activity was significantly higher, with one bout every 1.6 ± 0.2 days, than the dry season, when foraging bouts were performed every 1.9 ± 0.3 days. Foraging activity throughout the study colonies presented high temporal synchronization. In both seasons, foraging was negatively correlated with air temperature and positively correlated with humidity. The foraging trails were often re-utilized and ranged from 1 to 18.5 meters in length. No difference between seasons in the area potentially utilized by the study colonies was observed. Approximately 51000 individuals participated in the foraging bout during the dry season, whereas some 87000 individuals participated in the foraging bout during the wet season. This corresponds to 43 and 74% of the estimated total nest population for the dry and wet seasons respectively. The average ratio soldiers:workers during foraging was 1:1.2 in the dry season and 1:2 in the wet season. The higher frequency and number of individuals foraging during the wet season in the present study are likely to be a strategy from C. cyphergaster to store energy reserves to be utilized during the dry season. Received 28 November 2005; revised 29 May 2006 and 16 August 2006; accepted 1 September 2006.     

Population status and habitat preference of Soemmerring’s gazelle in Alledeghi Wildlife Reserve,Eastern Ethiopia

This study was undertaken to determine the current population size, structure and habitat preference of Soemmerring's gazelle [Nanger soemmerringii (Cretzschmar 1828)] in the Alledeghi Wildlife Reserve, NE Ethiopia. Animals were counted, both during dry and wet seasons, along 12 line transects each in three habitat types (grassland, tree‐scattered grassland and bushland) in 2015/16. Habitat type had nonsignificant effect on mean population density of Soemmerring's gazelle, but wet season mean density was significantly higher than dry season mean density. Estimated weighted mean (±95% CI) population density of the species in the reserve was 1.90 (±0.17) and 5.99 (±0.370) individuals/km² during the dry and wet seasons, respectively. Total population size of the species in the Alledeghi Wildlife Reserve was estimated at 826 ± 77 and 2,562 ± 158 individuals during the dry and wet seasons, respectively. Over half of the total population of Soemmerring's gazelle was represented by adult females during both seasons. Seasonal habitat preference of Soemmerring's gazelle was statistically significant, with greater preference for grassland habitat during wet season and for bushland habitat during dry season. In conclusion, this study has provided valuable data that will be used as a baseline for future population monitoring.     

北部湾近岸海域浮游动物群落结构特征及季节变化

2017年3月(枯水期)、7月(丰水期)和10月(平水期)分别对北部湾近岸海域44个站位的浮游动物进行了调查。结果共检出浮游动物251种和浮游幼体24类,其中枯水期138种(类),丰水期134种(类),平水期191种(类),分属河口低盐、近岸暖温、近岸暖水和外海暖水4个生态类群。优势种9种,其中枯水期以原生动物占绝对优势,丰水期以枝角类、桡足类和浮游幼体类占优势,平水期以十足类和浮游幼体类占优势。浮游动物丰度年均值为789.95个/m~3,呈现出枯水期(1540.19个/m~3)明显高于平水期(457.58个/m~3)和丰水期(372.08个/m~3)的季节变化特征;浮游动物生物量年均值为252.40 mg/m~3,生物量的季节变化与丰度变化不一致,平水期生物量(385.01 mg/m~3)明显高于枯水期(221.41 mg/m~3)和丰水期(150.78 mg/m~3)。多样性指数平水期最高(3.16),丰水期(2.35)次之,枯水期(2.22)最低。枯水期和丰水期北部湾近岸海域浮游动物生物量和丰度水平分布特征基本呈现自河口近岸海域向外海递增的趋势,平水期浮游动物生物量与丰度的空间分布较为均匀。浮游动物的种类组成结构以及优势种的演替对浮游动物的生物量和丰度季节变化有着重要的决定作用。径流导致的悬浮物、营养盐等的变化可能是决定北部湾近岸海域浮游动物生物量和丰度空间分布的主要因素。研究还表明与其他海湾相比,北部湾近岸海域浮游动物群落结构趋于小型化,需加大关注。     

Resource heterogeneity and ungulate population dynamics

It has been suggested that climatic variation has the effect on the dynamics of arid and semi-arid grazing systems of reducing animal numbers below the level at which they have much impact on vegetation or soils, and that spatial heterogeneity in resource availability serves to buffer herbivores against climatic variation. Modelling was used to test these hypotheses and to examine the interacting effects of temporal and spatial variability in plant production on animal population dynamics and defoliation intensity. The model distinguishes areas of the range that are accessible during wet and dry seasons, and examines the effect of seasonal restrictions in foraging area. It was established that the animal population is in long-term equilibrium with dry-season resources, on which it depends for survival; that dry season resource areas and outlying areas thus operate in a source-sink manner; and that the ratio of these areas determines the strength of consumer-resource coupling outside the dry-season range. A high ratio of dry season to wet season resources may support a sufficiently large animal population to impose non-trivial defoliation impacts on the outlying range. Increasing degrees of variability in primary production on areas used by animals for surviving the dry season increased the annual variation in animal abundance and reduced the mean. By comparison with a stable environment, for which the model predicts virtually stable animal numbers and constant, low defoliation intensity, variation in annual rainfall causes wide fluctuations in animal numbers and defoliation intensity. Under climatic variation, animal numbers can build up enough to impose much higher defoliation intensities than under a constant regime. Periodic intense defoliation is a consequence of climatic variability which is likely to make these environments more, not less, prone to ecological change.     

The numbers and distribution of elephant Loxodonta africana in the Rwenzori National Park and Chambura Game Reserve, Uganda

A series of aerial counts of elephant made between 1968 and 1972 in the Rwenzori National Park and Chambura Game Reserve, Uganda, is described. A summary is included of all previous aerial counts made in the region. Numbers present in the park since 1963 averaged 1752 during the dry seasons, some 3/5 of the wet season mean of 2896. Corresponding figures for the reserve are 325 and 501. The distribution was very significantly aggregated for each count and remained so when the totals for all counts were lumped. The distribution tended to be more aggregated in dry than in wet seasons. The overall density in the park was 1.43 elephant km-² with wet and dry season means of 1.74 and 1.05 respectively. Corresponding figures for the reserve are 2.06, 2.42 and 1.57 km-². The mean group size in the park was 6.3 elephant but there were significant variations over the whole range of observations although not between wet and dry season means. The elephant in the reserve were highly aggregated with a mean group size of 28.8. It is concluded that there was a significant rise in the wet season population of the park between 1963 and 1968 but that subsequently, numbers remained fairly stable. Numbers in the dry season and in the reserve at all seasons have not varied significantly since 1963. It is suggested that the wet season rise has been due to a reduction in the area of grazing land available outside the park at this time of year. It is concluded that vegetational differences are responsible for the un even distribution of elephant with human disturbance having an effect in some areas. It is believed that in the region censused, there are at least three distinct populations of elephant of which only that in the reserve is showing signs of stress.     

An ecological study of small rodents in the thicket-clump savanna of Lengwe National Park, Malawi

A community of small rodents was studied in thicket-clump and grassland savanna of Lengwe National Park, Malawi, from September 1984 to June 1985. Nine species were recorded on a 1·1 ha grid and five assessment lines, using a capture-mark-release technique. The three commonest species (and their percentage proportions) were Mastomys natalensis (47%), Acomys spinosissimus (24%) and Saccostomus campestris (11%). Population numbers on the grid fluctuated from–30 individuals/ha, and the numbers on the assessment lines fluctuated from–57 individuals. There were two peaks of population numbers during the year: the first was in the early wet season (when individuals emigrated from dry season refugia and there was limited reproduction) and the second was in the mid dry season (when young born at the end of the wet season entered the trappable population). The population was comprised mainly of subadults in the late dry season, adults and some young in the wet season, and young and subadults in the early and mid dry seasons. Population survival rates were low with only 30–50% of individuals surviving to the following month. The magnitude of population fluctuations are related to the strong seasonality of climate, flooding and grass characteristics; in this respect, the community of small mammals in Lengwe National Park shows similarities to those of the Kafue Valley in Zambia and the Chobe Valley in Botswana.