鹅喉羚夏季和冬季卧息地选择

2007年夏季(6—8月)及冬季(11—2008年1月),在卡拉麦里山有蹄类自然保护区研究了鹅喉羚(Gazella subgutturosa sairensis)的卧息生境选择。夏季测定了49个卧迹样方,36个对照样方;冬季测定了75个卧迹样方,75个对照样方。卡拉麦里山有蹄类自然保护区的鹅喉羚夏季主要选择平滩、下坡位,海拔910 m以上、与水源距离较远、远离道路、远离居民点、高隐蔽级、中低植被密度和中高草本密度的区域作为卧息地; 而冬季鹅喉羚主要选择山坡、阳坡和半阴半阳坡、中上坡位和下坡位、900—1 000 m的高度范围、离道路501—1 000 m以及大于2 000 m的距离、靠近居民点、中低隐蔽级、中等雪深(1.1—3 cm)、中高植被密度和中高草本密度的区域作为卧息地。主成分分析表明,鹅喉羚夏季卧息样方前4个主成分的累积贡献率达到86.57%,第1主成分主要反映卧迹样方的植物密度、草本密度、针茅(Stipa spp.)密度、至最近居民点距离、至永久水源最近距离和海拔的影响。冬季鹅喉羚卧息样方前4个主成分的累积贡献率达到73.88%,第1主成分主要反映卧迹样方的植物密度、草本密度、针茅密度和坡度的影响。     

天山盘羊夏季采食地和卧息地生境选择

2010年7-8月采用样线调查法及直接观察法对天山中部古仁郭楞高山区的盘羊天山亚种采食地和卧息地生境进行了研究。共调查5条沟系的12条样线,测量天山盘羊147个采食地和136个卧息地样方,分析了13类生态因子对天山盘羊采食地和卧息地选择的影响。研究结果表明,天山盘羊夏季采食地与卧息地在坡位、坡向、地貌类型、海拔高度、距最近家畜距离、距道路距离和距居民点距离差异极显著（P < 0.01）,植被高度差异显著（P < 0.05）,而其它生态因子差异性不显著（P > 0.05）;相对卧息地的选择而言,夏季盘羊采食地的选择更偏爱海拔较低,植被高度低,距离道路、居民点和最近家畜距离近的半阴半阳坡,山体中下位的高山草甸缓坡生境。逐步判别分析表明,距道路距离、距居民点距离、植被高度、距家畜距离4个生态因子可以用于判别夏季天山盘羊采食地与卧息地生境,正确区分率达到90.6%。     

半散放条件下赤麂卧息地特征分析

2006年4～8月,在海南省大田国家级自然保护区对位于E108°47′05·8″～108°47′12·0″、N19°05′55·7″～19°05′58·1″,面积为10400m2的围栏内6只半散放条件下赤麂(Muntiacus muntjak)的卧息生境进行了研究。将围栏内的面积划为104个10m×10m的样方,作为收集数据的基本单元。将有赤麂卧息的样方定义为卧息单元,反之为非卧息单元。赤麂选择在14个样方卧息,卧息地平均长(1·6643±0·6197)m、宽(1·1679±0·3123)m、高(0·8143±0·1445)m。采用逻辑斯蒂回归模型作为赤麂卧息地特征分析的数学模型,分析了在14个卧息单元中收集的11类生态因子。结果表明,赤麂卧息地的选择与草本高度、隐蔽度、灌木高度及灌木密度正相关。赤麂卧息地选择的预测模型可用以下数学表达式表示:ln[P/(1-P)]=-26·888 0·089×灌木密度 0·253×草本高度 0·114×隐蔽度 0·079×灌木高度。     

甘肃马鬃山盘羊春季卧息地的利用

2010年4～5月,在甘肃省马鬃山地区调查研究了盘羊的卧息地生境选择,共测得盘羊利用样方81个,对照样方81个。通过比较表明,马鬃山地区的盘羊夏季卧息地主要选择高海拔、阳坡、中坡位、坡度大、红砂植被、碎石地、植被密度低、远离道路和居民点、接近水源和隐蔽物、隐蔽程度好的区域。逻辑斯蒂回归分析表明,海拔(OR值1.614,95%CI1.248～4.419)、坡向(95%CI1.682～3.745)、坡位(95%CI0.839～3.156)、坡度(OR值1.705,95%CI1.227～2.369)、植被类型(95%CI0.682～2.732)、距水源距离(OR值0.180,95%CI0.041～0.787)、距道路距离(OR值1.628,95%CI2.598～3.941)、隐蔽级(OR值0.911,95%CI0.857～0.967)是盘羊春季卧息地选择的主导因子。     

贺兰山岩羊冬季对卧息地的选择

2003 年11～12月, 在贺兰山采用样带法对岩羊冬季卧息地的选择性进行了研究。共观察到94 个岩羊的卧息地, 结果表明岩羊对优势乔木的利用有选择性( x² = 17.01 , df = 5 , P < 0.05) , 偏好利用灰榆占优势的卧息地, 避免选择油松和青海云杉占优势的卧息地; 对坡向选择性利用( x²= 30.69, df =2, P < 0.05) , 偏好位于阳坡的卧息地, 避免利用阴坡; 对植被类型、坡位和风向的利用无选择性。对卧息地样方与在样带中随机设置的样方进行比较, 发现卧息地具有乔木密度低、食物丰富度低、隐蔽程度高、接近水源、接近裸岩、风速低和雪覆盖浅等特征。贺兰山的岩羊经常选择岩洞作为卧息地, 占总卧息地的62.77 %。对59 个岩洞和35 个非岩洞卧息地进行比较, 表明岩洞卧息地的坡度大、隐蔽程度高、风速低、保温性好、食物丰富度低和无雪覆盖。岩羊通常选择较宽的、深度和高度适中的岩洞作为卧息地。对各种生境因子的主成分分析表明前7 个特征值的累积贡献率已经达到了80.09%, 可以较好地反映岩羊卧息地的生境特征, 第1 主成分中隐蔽级、风向、风速、距裸岩距离和雪深具有重要作用, 其余6 个主成分中优势乔木、坡向、坡位和坡度也很重要。     

天山中部地区盘羊冬季采食地和卧息地的生境分离

采用样线法及直接观察法研究天山中部古仁郭楞地区盘羊天山亚种(Ovis ammon karelini)冬季采食地和卧息地的生境分离。2009年12月—2010年1月累计调查5条沟系的12条样线,测量盘羊采食地和卧息地样方分别为120个和114个。记录了样方所在地的海拔、植物种数、植被盖度、植被高度及距道路距离等13项生态因子。结果表明,天山盘羊冬季采食地与卧息地在植被高度、植被盖度、隐蔽级等生态因子差异不显著(P0.05);在海拔、坡度、坡位、距道路距离、距居民点距离、植物种数和雪深等生态因子差异极显著(P0.01),雪盖、坡向和地貌类型生态因子差异显著(P0.05)。逐步判别分析表明,由5个生态因子变量构成的方程能够区分盘羊冬季采食地与卧息地生境,正确率达到95.1%,按照其贡献值的大小排序依次为:雪深、距道路距离、海拔、坡度和植被高度。研究结果支持盘羊冬季采食地和卧息地之间存在明显的生境分离。     

贺兰山马鹿冬季取食和卧息生境选择

2007 年12 月至2008 年1 月,在贺兰山地区,利用痕迹检验法和直接观察法对马鹿阿拉善亚种的冬季取食和卧息生境选择进行研究。通过在选定的15 条沟段里进行调查,共测定了72 个取食利用样方,59 个卧息利用样方和131 个对照样方的18 种生态因子。结果表明,马鹿在冬季偏好的取食地为平滑起伏坡,以酸枣、柳为优势乔木、混合型树林或空地,乔木高大稀疏、间距较远,灌木密度大,草本盖度较高,位于< 15°的半阴半阳坡的下坡位,距裸岩远,隐蔽度高;偏好的卧息地在山地疏林草原带的平滑起伏坡上,以酸枣、柳为优势乔木、混合型树林或空地,乔木高大稀疏,灌木矮小、稀疏且距离较远,草本盖度较高,位于< 15°阳坡的下坡位,远离裸岩,隐蔽程度高。马鹿冬季的取食和卧息生境在草本盖度和隐蔽度上差异极显著。相对于卧息生境,马鹿冬季的取食生境对草本盖度和隐蔽度要求更低一些。马鹿冬季取食地的资源选择函数为1.155 - 0.149 × 乔木高度- 0.066 × 草本盖度+ 0.190 × 坡度,模型的正确判别率为86.8% ;马鹿冬季卧息地的资源选择函数为- 30.936
+ 0.494 × 乔木高度+ 0.257 × 坡度-0.002 × 海拔高度+ 0.387 × 隐蔽度,模型的正确判别率为95.8% 。食物、隐蔽条件以及贺兰山的独特地形特征是影响马鹿冬季取食和卧息生境选择的主要因素。     

湖北石首麋鹿国家级自然保护区麋鹿冬季卧息地微生境选择

掌握麋鹿种群冬季卧息地的微生境特征,可为冬季麋鹿种群的科学保护和有效管理提供理论依据.2011年12月-2012年2月,通过对61个利用样方和70个对照样方的比较调查,研究了湖北石首麋鹿国家级自然保护区内麋鹿冬季卧息地微生境选择.结果表明,湖北石首麋鹿国家级自然保护区内麋鹿冬季主要选择在食物丰富、植被盖度大、隐蔽度高的生境卧息.主成分分析表明,影响冬季麋鹿卧息地微生境选择的决定性因子是食物因子、温度因子、舒适因子.本研究分析了麋鹿种群对冬季卧息地生态因子选择的要求和原因,对麋鹿自然野化、种群就地与迁地保护均具有十分重要的意义.     

麋鹿夜间卧息地选择的季节变化

卧息地选择是野生动物对生态环境的行为适应。为了探讨麋鹿(Elaphurus davidianus)夜间卧息地选择的季节变化, 2013年11月至2014年12月, 采用跟踪调查法与直接观察法, 对湖北石首麋鹿国家级自然保护区围栏内麋鹿184个夜间卧息样方和184个对照样方的生态因子信息进行了观测记录。结果表明: 麋鹿春、秋、冬3个季节夜间卧息时均选择隐蔽度较高、草本盖度较高、食物丰富度较高、距隐蔽物(芦苇或树林)较近的林地生境(P < 0.05), 并且春、秋季夜间选择在距道路距离与距居民点距离上的差异不显著(P > 0.05); 夏季夜间选择在草本盖度较低、食物丰富度较低、隐蔽度较低、距隐蔽物较近、距道路与居民点距离较远、距水源较近的滩涂生境卧息(P < 0.05); 冬季夜间选择在风速较小、距道路与居民点较近的生境卧息。判别分析表明: 草本盖度、食物丰富度、距道路距离、隐蔽度、风速、距水源距离以及距隐蔽物距离这7个因子组成的判别函数可区分不同季节麋鹿的夜间卧息地, 且麋鹿在不同季节的夜间卧息地特征存在部分重叠, 这可能与不同季节间食物、水、温度与人为干扰等因子的差异性有关。建议该保护区扩大饲料基地面积、保留麋鹿卧息隐蔽环境、减少人为干扰、控制长江故道水位。     

高原兔夏季卧栖地生境利用关键因子分析

研究阿尔金山国家级自然保护区高山草甸和高山荒漠区高原兔Lepus oiostolus夏季生境卧息地利用的主要影响因子,为高原兔的科学管理提供依据。2011—2013年夏季,累计调查高原兔卧息地5 m×5 m样方32个,另外在附近相同生境类型中设置对照样方33个。记录样方所在地的植物种数、植被盖度、植被高度、土壤硬度以及距道路的距离等指标。结果表明,卧息地和对照样方在植物种数、土壤硬度等方面差异有统计学意义(P<0.05),而在隐蔽级、植被高度、植被密度等方面差异有高度统计学意义(P<0.01)。Vanderloeg和Scavia选择指数Ei、选择系数Wi分析显示高原兔卧栖地偏好选择高度在30 cm以上、植被盖度大于30%且密度小于80株/m2,隐蔽级在10 cm以上,土质较软(6~9 kg/cm2)的小生境。主成分分析表明影响高原兔卧息地利用的主要因子依次是:植被密度(-0.898),植被盖度(-0.812)和隐蔽级(0.764)。高原兔偏爱植被高度更高、植物密度更低、隐蔽级更高、土壤较软的小生境。我们的结果为高原兔的科学管理提供了重要依据。     

阿尔泰山南部科克森山和卡拉麦里山盘羊冬季卧息地的选择

2007 年11 月至2008 年1 月,在阿尔泰山南部科克森山和卡拉麦里山采用样线法研究了盘羊冬季卧息地
的选择性。结果表明,两地区的盘羊对冬季卧息地的利用均有选择性,两地区盘羊偏好利用山坡做卧息地,避
免选择山沟和平滩卧息;偏好位于半阴和半阳坡的卧息地,避免利用阴坡,对阳坡随机利用;偏好位于上坡位
和中坡位的卧息地,对下坡位则为随机利用。通过与对照样方比较,科克森山和卡拉麦里山盘羊冬季卧息地均
以植物科数多、植物种数多、植物密度高、灌木株数小、驼绒藜株数少、接近隐蔽物、隐蔽级高和雪覆盖浅为
主要特征。在科克森山,盘羊通常选择坡度大、雪覆盖浅的位置作为其卧息地。在卡拉麦里山盘羊通常选择坡
度大的地方作为其卧息地。科克森山和卡拉麦里山盘羊卧息地变量前6 个特征值的累积贡献率分别达到了
80.75%和82. 58% ,较好地反映了盘羊卧息地的生境特征。科克森山和卡拉麦里山盘羊卧息地第1 主成分贡献
率分别达到了23.04% 和24. 33%。在两地区,植物科数、植物种数、灌木种数、雪深和坡度5 个因子的载荷系
数均为正值,具有较大的作用。其余5 个主成分中隐蔽级、海拔、距水源距离和距居民点距离也很重要。     

Assessing possible hybridization among managed Nubian ibex in North America

Hybridization among closely related species is a concern in zoo and aquarium populations where unpedigreed animals are frequently exchanged with the private sector. In this study, we examine possible hybridization in a group of Nubian ibex (Capra nubiana) imported into the Association of Zoos and Aquariums’ (AZA) Species Survival Program (SSP) from a private institution. These individuals appeared smaller in stature than adult SSP Nubian ibex and were excluded from breeding recommendations over the concern that they were hybrids. Twenty-six microsatellites were used to rule out recent hybridization with domestic goats, Siberian ibex (Capra sibirica), and Alpine ibex (Capra ibex). We argue that natural phenotypic variation across the large geographic range of Nubian ibex may account for the small stature of the imported ibex, as private institutions may have historically acquired individuals from locations that differed from the SSP founders. However, the imported Nubian ibex appeared genetically differentiated from the SSP Nubian ibex and may represent a source of genetic variation for the managed population.     

Is the development of infectious keratoconjunctivitis in Alpine ibex and Alpine chamois influenced by topographic features?

Infectious keratoconjunctivitis (IKC) caused by Mycoplasma conjunctivae is a widespread ocular affection of free-ranging Caprinae in the Alpine arc. Along with host and pathogen characteristics, it has been hypothesized that environmental factors such as UV light are involved in the onset and course of the disease. This study aimed at evaluating the role of topographic features as predisposing or aggravating factors for IKC in Alpine chamois (Rupicapra rupicapra rupicapra) and Alpine ibex (Capra ibex ibex). Geospatial analysis was performed to assess the effect of aspect (northness) and elevation on the severity of the disease as well as on the mycoplasmal load in the eyes of affected animals, using data from 723 ibex and chamois (583 healthy animals, 105 IKC-affected animals, and 35 asymptomatic carriers of M. conjunctivae), all sampled in the Swiss Alps between 2008 and 2010. An influence of northness was not found, except that ibex with moderate and severe signs of IKC seem to prefer more north-oriented slopes than individuals without corneal lesions, possibly hinting at a sunlight sensitivity consequent to the disease. In contrast, results suggest that elevation influences the disease course in both ibex and chamois, which could be due to altitude-associated environmental conditions such as UV radiation, cold, and dryness. The results of this study support the hypothesis that environmental factors may play a role in the pathogenesis of IKC.     

Bed and bed-site reuse by western lowland gorillas (<Emphasis Type="Italic">Gorilla g. gorilla</Emphasis>) in Moukalaba-Doudou National Park,Gabon

In this paper we describe bed (nest) and bed-site reuse by western lowland gorillas (Gorilla g. gorilla) in Moukalaba-Doudou National Park, south-eastern Gabon. During an eight-month study 44 bed sites and 506 beds were found. Among these, 38.6% of bed sites and 4.1% of beds were reused. We analyzed the monthly frequency of bed-site reuse in relation to rainfall, fruit abundance, and fruit consumption by the gorillas. The different frequency of bed-site reuse in the rainy and dry seasons was not significant. More bed-site reuse was observed during the fruiting season than during the non-fruiting season. Results from fecal analysis suggested that gorillas ate more fruit in the fruiting season than in the non-fruiting season. The frugivorous diet of western gorillas may possibly cause gorillas to stay in some areas and, consequently, reuse their bed sites. Reuse of bed sites by gorillas suggests their frequent return to an area where preferred fruit is readily available. A higher percentage of arboreal beds may also affect bed-site reuse, because of the shortage of bed material.     

Epizootiologic investigations of selected abortive agents in free-ranging Alpine ibex (Capra ibex ibex) in Switzerland

In the early 2000s, several colonies of Alpine ibex (Capra ibex ibex) in Switzerland ceased growing or began to decrease. Reproductive problems due to infections with abortive agents might have negatively affected recruitment. We assessed the presence of selected agents of abortion in Alpine ibex by serologic, molecular, and culture techniques and evaluated whether infection with these agents might have affected population densities. Blood and fecal samples were collected from 651 ibex in 14 colonies throughout the Swiss Alps between 2006 and 2008. All samples were negative for Salmonella spp., Neospora caninum, and Bovine Herpesvirus-1. Antibodies to Coxiella burnetii, Leptospira spp., Chlamydophila abortus, Toxoplasma gondii, and Bovine Viral Diarrhea virus were detected in at least one ibex. Positive serologic results for Brucella spp. likely were false. Overall, 73 samples (11.2%) were antibody-positive for at least one abortive agent. Prevalence was highest for Leptospira spp. (7.9%, 95% CI=5.0-11.7). The low prevalences and the absence of significant differences between colonies with opposite population trends suggest these pathogens do not play a significant role in the population dynamics of Swiss ibex. Alpine ibex do not seem to be a reservoir for these abortive agents or an important source of infection for domestic livestock in Switzerland. Finally, although interactions on summer pastures occur frequently, spillover from infected livestock to free-ranging ibex apparently is uncommon.     

Effects of food quality, diet preference and water on patch use by Nubian ibex

Measuring patch use of a forager can reveal not only its cost and benefits from foraging, but also the importance of environmental factors and the significance of energy, nutrients and predation risk to its fitness. In order to assess the effects of various variables that may affect the foraging behavior of free-ranging Nubian ibex in the Negev Desert, Israel, giving-up densities (GUD) in artificial food patches were measured following Kotler et al. In particular, we tested the effects of food quality and water availability on Nubian ibex foraging behavior. To do so, we (1) tested whether the tannic acid content of food affected diet preferences, (2) assayed their diet selection strategy, (3) tested if the foraging decisions of the Nubian ibex were affected by the availability of water and (4) determined the nutritional relationship between food resources and water. Nubian ibex had lower GUDs and used resources patches more intensively where water was available, the food quality was higher and the location was closer to the escape terrain. Nubian ibex showed an expanding specialist diet selection when exploiting resource patches with a mix of items that differ in quality. Overall, food and water were complementary resources for Nubian ibex, and tannins reduced food quality. These factors help to determine patch foraging behavior decisions in Nubian ibex and contribute to habitat quality.