鳄蜥生活习性的观察

2004～2005年,通过野外调查和半自然条件下饲养的方法研究了鳄蜥的生活习性.鳄蜥主要栖息于阔叶林、针阔混交林、灌木林荫、竹林4种植被类型的山冲溪沟之中.活动季节是4月中旬至10月上旬.主要以各种昆虫为食,对食物的种类有一定的选择性.卵胎生,4～5月产仔,双亲无育幼行为.鳄蜥在生长过程中有蜕皮现象.     

广东罗坑自然保护区鳄蜥夏季生境特征

2005年6—8月,在广东省罗坑自然保护区对36处鳄蜥的生境特征进行了研究。采用样线调查法,在保护区内鳄蜥分布区随机选取了30条溪沟进行调查,对每处有鳄蜥分布的生境测量了15个相关的生态因子。通过主成分分析发现,回水塘长度和宽度、水源距离、水流速度、栖枝高度、栖枝直径、干扰距离、植被类型、植被盖度等9个生态因子对鳄蜥的生境选择有显著影响,而回水塘底质组成、回水塘水深、栖枝枯活状况、栖枝角度、溪沟类型和溪沟坡向6个生态因子的影响不显著。鳄蜥偏好的生境可归结为回水塘长度、宽度中等(均为1.0—2.0m),有位于水源正上方的栖枝,水流速度缓慢,栖枝高度0.5—1.0m、栖枝直径≤1.00cm,干扰距离>500m,植被类型为常绿阔叶林、植被盖度>60%的生境。建议提高当地居民的保护意识,重点保护水源林和溪沟两侧的植被。     

广东罗坑自然保护区鳄蜥夏季生境特征

2005年6—8月，在广东省罗坑自然保护区对36处鳄蜥的生境特征进行了研究。采用样线调查法，在保护区内鳄蜥分布区随机选取了30条溪沟进行调查，对每处有鳄蜥分布的生境测量了15个相关的生态因子。通过主成分分析发现，回水塘长度和宽度、水源距离、水流速度、栖枝高度、栖枝直径、干扰距离、植被类型、植被盖度等9个生态因子对鳄蜥的生境选择有显著影响，而回水塘底质组成、回水塘水深、栖枝枯活状况、栖枝角度、溪沟类型和溪沟坡向6个生态因子的影响不显著。鳄蜥偏好的生境可归结为：回水塘长度、宽度中等(均为1.0—2.0 m)，有位于水源正上方的栖枝，水流速度缓慢，栖枝高度05—1.0 m、栖枝直径≤1.00 cm，干扰距离>500 m，植被类型为常绿阔叶林、植被盖度>60%的生境。建议提高当地居民的保护意识，重点保护水源林和溪沟两侧的植被。     

广东省罗坑自然保护区鳄蜥对溪沟林型的选择

2006年5—9月在广东省罗坑自然保护区,对大竹园管护站所辖区域内鳄蜥栖息溪沟的林型进行了调查,采用选择指数法研究了鳄蜥对溪沟林型的选择性。共调查了154只鳄蜥的生境特征,并对5种溪沟林型(常绿阔叶林、针阔混交林、针叶林、竹林和灌草)进行了样方调查。结果表明:鳄蜥对溪沟林型的选择是非随机的,偏好常绿阔叶林,对竹林接近于随机选择,回避其它林型;鳄蜥选择常绿阔叶林可能与其植被盖度较高、涵养水源能力强以及土壤有机质含量高有关。建议加强对常绿阔叶林的保护工作,以更好地保护鳄蜥。     

半自然条件下鳄蜥的管理

2005年7～10月我们将人工饲养鳄蜥（3条幼蜥、1条亚成蜥、5条成蜥）置于半放归栖息地进行圈养.半放归栖息地结合野外鳄蜥的生境,在半自然圈养过程中对鳄蜥进行分组管理,人工饲养的鳄蜥出现了野外鳄蜥的种群活动节律.结果表明：9月幼蜥树栖达10.38%,10月鳄蜥以在穴为主;不同年龄的鳄蜥,各种行为的时间分配无显著差异（P＞0.05）,体现了野生鳄蜥遗传特征.本文还对鳄蜥的疾病防治进行了初步探讨.     

广东罗坑自然保护区鳄蜥生境选择的季节性差异

2006年3-10月,在广东省罗坑鳄蜥自然保护区利用直接观察法对鳄蜥春、夏、秋3季的生境选择进行研究。春、夏、秋3季各测定了31、71、31个有鳄蜥样方以及50、90、51个对照样方的14种生态因子。利用生态因子对比分析和逐步判别分析确定各季节生境选择的主要影响因素。结果表明,春季影响鳄蜥生境选择的主要影响因素是溪沟底质中沙的含量和植被盖度,正确判别率为97.5%;夏季影响鳄蜥生境选择的主要影响因素是溪沟底质中沙的含量、植被盖度、溪流宽度和枯枝百分比,正确判别率为94.4%;秋季影响鳄蜥生境选择的主要影响因素是溪沟底质中沙的含量、植被盖度和可利用食物量,正确判别率为97.6%。在区分春、夏、秋3季鳄蜥生境选择方面有一系列生态因子发挥作用,依照贡献值的大小依次为可利用食物量、干扰距离、枯枝百分比、溪水流速、溪沟坡度和溪宽等6个因子,由这6个变量构成的方程对春、夏、秋3季鳄蜥生境的正确区分率达到76.7%。判别函数的分析表明,春、夏、秋3季鳄蜥的生境选择具有较高的差异性,以判别函数建立的判别分类图表明,春、夏季以及夏、秋季鳄蜥的生境选择重叠较多,而秋季与春季的重叠较少。     

半自然状态下鳄蜥活动时间分配的初步研究

在半自然的条件下采用瞬时扫描法对鳄蜥活动时间分配进行了初步的研究,结果表明:在池养鳄蜥的活动时间分配中,静栖占69·09%,在穴占28·82%,移动占0·80%,捕食占0·28%,晒太阳占0·44%,其它占0·58%;比较了不同性别鳄蜥的活动时间分配,其中雄性鳄蜥用在移动的时间占1·15±1·22%,雌性为0·45±1·00%,经过单因素检验显示其差异显著(P<0·01),其它行为活动时间分配差异不显著;初步比较了不同生境中鳄蜥的行为差异,结果显示鳄蜥在池养的条件下弹性行为的表现频次正在下降。     

四川西部石渠地区夏季藏狐巢穴选择的生境分析

通过对四川石渠地区夏季藏狐洞穴生境选择的研究 ,以水源距离、洞口朝向、坡向、坡度、坡位、植被类型及鼠兔和鼠类洞穴等 7项指标为变量 ,运用主成分分析和聚类分析相结合的方法对收集到的 5 4个藏狐洞穴样本进行了分析。主成分分析在 4个主成分下达到 85 %的显著性。在第一主成分中水源距离、坡度和坡位是重要的影响变量 ,在另外 3个主成分中鼠类洞穴数量以及植被类型两变量也非常重要。聚类分析显示 ,5 4个洞穴样本在 3个水平上聚成 5类。藏狐易于选择草甸地带 ,中缓坡和低坡位 ,坡向多为阳坡或半阳坡 ,水源距离小于5 0 0m的地方筑巢 ,其穴口朝向多位于 135°～ 36 0°之间。此外 ,鼠兔和鼠类洞穴在藏狐洞穴样方内的出现 ,但数量变异较大 ,揭示小型哺乳动物和藏狐之间可能存在着复杂的相互关系。通过对四川石渠地区夏季藏狐洞穴生境选择的研究 ,以水源距离、洞口朝向、坡向、坡度、坡位、植被类型及鼠兔和鼠类洞穴等 7项指标为变量 ,运用主成分分析和聚类分析相结合的方法对收集到的 5 4个藏狐洞穴样本进行了分析。主成分分析在 4个主成分下达到 85 %的显著性。在第一主成分中水源距离、坡度和坡位是重要的影响变量 ,在另外 3个主成分中鼠类洞穴数量以及植被类型两变量也非常重要。聚类分析显示 ,5 4     

长江河口湿地不同植被中无齿螳臂相手蟹的分布及其洞穴利用

无齿螳臂相手蟹(Chiromantes dehaani)是长江河口中、高潮滩的优势底栖动物之一,具有重要的生态功能.由于其经济价值较低,所受关注很少.本文调查了相似高程芦苇(Phragmites australis)带、芦苇斑块、菰(Zizania aquatica)植被以及裸地4种生境中无齿螳臂相手蟹的数量分布及其洞穴的利用情况.有植被分布的3种生境间植株密度、植株高度和植物干重生物量(地上部分)差异显著(P＜0.001);4种生境问,陷阱桶采样获取的无齿螳臂相手蟹数量分布(P＜0.001)和性比(P=0.001)差异显著;裸地区域没有无齿螳臂相手蟹可用的洞穴分布,芦苇带、芦苇斑块和菰植被间无齿螳臂相手蟹可用的洞穴密度(P＜0.019)、单位洞穴蟹个体数(P＜0.001)差异显著,挖掘洞穴采样获取的无齿螳臂相手蟹密度差异接近显著水平(P=0.067),洞穴占用率(P=0.667)、不同洞穴占用方式频次组成(P＞0.05)差异不显著;无齿螳臂相手蟹可利用洞穴密度与植株密度、植物干重生物量显著负相关(P＜0.05),而挖掘洞穴采样获取的无齿螳臂相手蟹密度与植株高度(P=0.077)相关性接近显著水平且与洞穴密度(P＜0.001)显著正相关.这些结果表明盐沼植被对无齿螳臂相手蟹的分布和洞穴利用存在影响.而进一步探讨盐沼不同植被对无齿螳臂相手蟹分布的影响,需要先了解无齿螳臂相手蟹在不同植被中分布格局在时间上的变化,并结合无齿螳臂相手蟹在不同植被间的迁移行为以及繁殖周期等进行探讨.     

广东罗坑自然保护区鳄蜥的体温调节及静止代谢率的热依赖性

探讨鳄蜥（Shinisaurus crocodilurus）的体温调节和静止代谢率及其热依赖性特征,测定了在自然和实验室条件下的环境温度、鳄蜥体温以及静止代谢率（RMR）等热生物学指标。结果显示：在自然条件下,鳄蜥的野外活动体温（Th）稍高于基质温度（Tc）和空气温度（Td）并与后二者呈正相关关系（Tb=11．65＋0．47Tc,r^2=0．34,F1.75=39．11,P〈0．0001;Tb=11．61＋0．46Td,r^2=0．56,F1.75=96．56,P〈0．0001）。鳄蜥在野外的活动体温存在明显的月份间差异,但无性别及年龄上的差异。环境温度为15℃-30℃的实验条件下,鳄蜥的静止体温（Tb）与环境温度（Ta）呈正相关关系：Tb=12．450＋0．5641Ta（F1.110=11．34,r^2=0．997,P〈0．001）;在缺乏温度梯度的环境中,尽管鳄蜥的体温、空气温度和基质温度都有显著的昼夜差异,但体温、空气温度和基质温度的日平均温度之间无显著差异。鳄蜥的RMR不存在雌雄个体间的差异,并与环境温度呈正相关关系。分析显示鳄蜥的体温既有行为调节也有生理调节,其体温调节及RMR符合变温动物的热生物学特征,但是相对于其他活动较多的蜥蜴而言,鳄蜥的生理调节能力较强,这可能与其活动时间分配中静栖占绝大部分的行为特点是相适应的[动物学报54（6）：964-971,2008]。     

Depth of artificial Burrowing Owl burrows affects thermal suitability and occupancy

Many organizations have installed artificial burrows to help bolster local Burrowing Owl (Athene cunicularia) populations. However, occupancy probability and reproductive success in artificial burrows varies within and among burrow installations. We evaluated the possibility that depth below ground might explain differences in occupancy probability and reproductive success by affecting the temperature of artificial burrows. We measured burrow temperatures from March to July 2010 in 27 artificial burrows in southern California that were buried 15–76 cm below the surface (measured between the surface and the top of the burrow chamber). Burrow depth was one of several characteristics that affected burrow temperature. Burrow temperature decreased by 0.03°C per cm of soil on top of the burrow. The percentage of time that artificial burrows provided a thermal refuge from above‐ground temperature decreased with burrow depth and ranged between 50% and 58% among burrows. The percentage of time that burrow temperature was optimal for incubating females also decreased with burrow depth and ranged between 27% and 100% among burrows. However, the percentage of time that burrow temperature was optimal for unattended eggs increased with burrow depth and ranged between 11% and 95% among burrows. We found no effect of burrow depth on reproductive success across 21 nesting attempts. However, occupancy probability had a non‐linear relationship with burrow depth. The shallowest burrows (15 cm) had a moderate probability of being occupied (0.46), burrows between 28 and 40 cm had the highest probability of being occupied (>0.80), and burrows >53 cm had the lowest probability of being occupied (<0.43). Burrowing Owls may prefer burrows at moderate depths because these burrows provide a thermal refuge from above‐ground temperatures, and are often cool enough to allow females to leave eggs unattended before the onset of full‐time incubation, but not too cool for incubating females that spend most of their time in the burrow during incubation. Our results suggest that depth is an important consideration when installing artificial burrows for Burrowing Owls. However, additional study is needed to determine the possible effects of burrow depth on reproductive success and on possible tradeoffs between the effects of burrow depth on optimal temperature and other factors, such as minimizing the risk of nest predation.     

Effect of available burrow densities of plateau pika (Ochotona curzoniae) on soil physicochemical property of the bare land and vegetation land in the Qinghai-Tibetan Plateau

The available burrow densities of plateau pika (Ochotona curzoniae) regulate the soil physicochemical property in alpine meadow. A field survey was conducted to investigate the effect of available burrow densities of plateau pika on soil physicochemical property of bare land (bare patch produced by burrowing behavior of plateau pika) and vegetation land (land covered with vegetation). This study indicated that the increase in available burrow of plateau pika caused the soil water content at 0–10 cm layer of bare land and that at 10–20 cm of vegetation land to reduce, and caused the soil water content at 10– 20 cm layer of bare land and that at 0–10 cm layer of vegetation land to firstly increase and then decline. In the increasing process of available burrow of plateau pika, the soil silt content firstly increased and then decreased, and soil sand content firstly decreased and then increased. With the increase of available burrow of plateau pika, the soil porosity at 0–10 cm layer of bare land and that at 10–20 cm layer of vegetation land decreased, while the soil porosity at 10–20 cm layer of bare land and that at 0–10 cm of vegetation land firstly increased and then decreased. Soil pH value, soil organic matter, total nitrogen and total phosphorus content firstly increased and then decreased, peaking at 14 available burrows per 625 m², while total soil potassium content did not respond to available burrow densities of plateau pika. This study suggested that the proper available burrows existing in the alpine meadow increased soil permeability, accelerated soil moisture to penetrate deeply, increased the proportion of soil silt, and improved the soil nutrient; however, this beneficial effect was strongly influenced by the available burrow density of plateau pika, implying that plateau pika did not benefit soil structure when its available burrow was over 34 number/625 m².     

Spiders provide important resources for an endangered lizard

Conservation management requires knowledge of how a target species interacts with other species. Some relatively common species can modify the environment to the advantage of rarer, endangered species. Thus, local enhancement of those common species can positively influence remaining populations of the rarer species. The endangered pygmy bluetongue lizard Tiliqua adelaidensis inhabits burrows that are constructed by lycosid and mygalomorph spiders. We recorded 490 burrows in a 1 ha plot at the end of one season, and then observed at regular intervals the formation and loss of burrows, and the changes in occupancy status of each burrow over the next season. We found spiders in 94% of all newly constructed burrows and deduced that they had built the burrows. We found no evidence that lizards dug new burrows or deepened existing burrows. The numbers of both lizards and spiders in the burrows declined over the spring and summer, with lizards moving from their burrows more often early in the season than later. However, there was no strong trend for lizards to replace spiders in burrows. In fact, lizards tended to occupy deeper burrows than spiders, suggesting little negative impact of lizards on spiders. However, spiders had a positive impact on lizards by providing the refuge burrows central for lizard survival. Although lizards readily accept artificial burrows, long-term conservation for the lizards must include viable spider populations to maintain a supply of suitable burrow refuges.     

Burrow morphology and dynamics of mudshrimp in Asian soft shores

Mudshrimps are important soft shore bioturbators but research on the ecology of tropical species has received less attention when compared with their temperate counterparts. The mudshrimp Austinogebia edulis is common on Asian soft shores and lives in burrows for its entire adult life. Epoxy resin casting of A. edulis burrows showed that they were approximately Y-shaped, with an upper U-part and the lower central shaft part. The burrows had two openings extending to the surface; the mean distance between the two openings was 11.0 cm in Hong Kong and 26.4 cm in Taiwan. Openings of the burrows had small chimneys. The tunnels of the burrows were circular, narrow and with a smooth surface (tunnel diameter corresponded to shrimp carapace width). Each burrow was inhabited by a single shrimp and burrows were inter-connected during the mating and reproductive season. Each burrow had four to 12 spherical chambers, which were free of detritus. The chambers were thought to be used for suspension feeding, current generation and as turning points. The depth of burrows was up to 1.1 m. Multivariate analysis on various burrow parameters showed that burrows collected on a mud flat in Taiwan were deeper, had a wider distance between the openings and a larger volume than burrows collected from a sandy shore in Hong Kong, suggesting that burrow architecture is variable between shore types. Burrow architecture, however, did not vary between tidal levels, seasons and shrimp density on the shores in Hong Kong, indicating that the burrows were quite stable within the substratum and were not affected by environmental and biological factors.     

Location of long‐term communal burrows of a threatened arid‐zone lizard in relation to soil and vegetation

The great desert skink (Liopholis kintorei) of the Egerniinae subfamily (Reptilia: Scincidae) is a communal burrowing lizard that inhabits arid spinifex grasslands in central Australia. Great desert skink activity is centred in and around the burrows which are inhabited for many years. However, it is not known whether skinks select burrow sites with specific attributes or how continuing occupancy of burrows is influenced by the surrounding habitat; especially post‐fire, when plant cover is reduced. Here, we test whether great desert skink burrows in areas burnt 2 years previously and in longer unburnt areas are associated with particular habitat attributes, and whether there are differences between occupied and recently abandoned burrow sites. Vegetation composition, cover and soil surface characteristics at 56 established great desert skink burrows, including occupied and recently unoccupied burrows, were compared with 56 random nearby non‐burrow control sites. Burrow sites had higher plant cover compared with the surrounding landscape in both recently burnt and longer unburnt areas and were more likely to be associated with the presence of shrubs. Soil stability and infiltration were also higher at burrow sites. However, we found no evidence that burrows with lower cover were more likely to be abandoned. Our results suggest that great desert skinks may actively select high cover areas for burrow construction, although differences between burrow and control sites may also partly reflect local changes to plant cover and composition and soil properties resulting from burrow construction and long‐term habitation of a site. Further research should determine if burrows with shrubs or higher plant cover provide greater protection from predators, more structural stability for burrow construction, increased prey abundance or other benefits. We recommend that maintenance of areas with relatively higher plant cover be prioritized when managing great desert skink habitat.     

Responses of the endangered pygmy bluetongue lizard to conspecific scats

Many animals use chemical signals for communication between conspecifics and for territory marking. The pygmy bluetongue lizard is normally solitary, focussing activity around the entrance of its burrow, from where it ambushes prey, and rarely contacts other individuals. In this paper we examined whether lizards in laboratory experiments alter their behaviour in the presence of scats from conspecifics. In the first experiment, when lizards were offered a choice of two vacant burrows with or without a scat close to the entrance, they tongue flicked more often at the burrow entrance when the scat was present, and more often chose to occupy the burrow with the scat. An interpretation is that lizards use scat signals to recognise burrows that may be suitable because they have previously been occupied by a conspecific, but that they approach those burrows cautiously in case a resident is still present and likely to resist a takeover. Scats from male lizards were inspected (by both sexes) for longer than scats of female lizards. In the second experiment, when resident lizards were presented with scats outside of their burrows, they inspected and tongue flicked at those scats more often if the scat came from a male than a female lizard, but there was no definitive evidence from our experiments that lizards differentiated in their response to scats from lizards that were found close to or far from the test lizard. The results were consistent with a communication system in which lizards use scats to advertise their presence, independent of any direct contact.     

Habitat selection by the Spiny-tailed lizard (Uromastyx aegyptia): A view from spatial analysis

Many factors affect the habitat selection for animal species, which in turn may greatly affect their distribution in different ecosystems. Understanding the processes that affect habitat selection is also critical for guiding and managing conservation initiatives. Our study aimed to assess the habitat selection by free-ranging Spiny-tailed lizard (Uromastyx aegyptia) by analyzing a geospatial data connecting its burrow parameters to different habitat characteristics within selected sites in Hail region, Saudi Arabia. We examined evidence and patterns of significant spatial clustering for (366) active burrows by linking their parameters (burrow entrance size, burrow entrance width and burrow entrance height), their reference geographical locations and, two habitat characteristics defined by soil type and vegetation cover. The objective of the analysis was to increase the understanding on the burrows aggregation process in the space and, to describe its possible relation to other spatial habitat configurations. Analysis of distances based on the Nearest Neighbor Index (NNI) and hotspots detection in Nearest neighbor hierarchical clustering (Nnh) suggested twelve (12) spatial clusters located within the study area. In addition, a spatial ordinary least square (OLS) and Poisson regression models revealed significant effects of soil type and vegetation cover on burrow parameters (OLS, p < 0.05; Poisson, p < 0.001), which indicate a strong association between burrows parameters and habitats characteristics. Findings from the study also suggest that other factors such as elevations, highways, and human settlement concentration spots could possibly play a major role in defining burrow spatial aggregation and furthermore have a significant impact on habitat selection.     

青藏高原东缘高寒森林小型兽类地表洞穴选择与生境特征

高寒森林地表的小型兽类洞穴是生态系统重要的景观特征,对于认识小型兽类的分布格局及其生态功能具有重要意义.为此,以青藏高原东缘典型高寒森林生态系统小型兽类洞穴为对象,于2015年夏季(7—9月)研究了其地表分布与生境特征.结果表明: 小型兽类洞穴平均洞口密度为182.8个·hm^-2,不同森林植被类型显著影响洞穴密度,表现为针叶林(328.6个·hm^-2)>针阔混交林(160.0个·hm^-2)>灌木林(125.0个·hm^-2)>阔叶林(81.5个·hm^-2)>竹林(66.7个·hm^-2). Mann-Whitney U Test和主成分分析表明,小型兽类栖息样地的乔木郁闭度、乔木均高、乔木胸径、乔木密度、地表植被盖度、倒木密度、倒木覆盖度、灌木均高都显著大于非栖息样地;乔木因子是决定小型兽类生境选择的首要因子,贡献率最大(44.8%),其次是倒木因子(23.2%)和灌草丛因子(13.9%).说明高寒森林地表有明显的小型兽类洞穴分布,其分布格局主要受植被和倒木的影响.     

Lizards cooperatively tunnel to construct a long-term home for family members

Constructing a home to protect offspring while they mature is common in many vertebrate groups, but has not previously been reported in lizards. Here we provide the first example of a lizard that constructs a long-term home for family members, and a rare case of lizards behaving cooperatively. The great desert skink, Liopholis kintorei from Central Australia, constructs an elaborate multi-tunnelled burrow that can be continuously occupied for up to 7 years. Multiple generations participate in construction and maintenance of burrows. Parental assignments based on DNA analysis show that immature individuals within the same burrow were mostly full siblings, even when several age cohorts were present. Parents were always captured at burrows containing their offspring, and females were only detected breeding with the same male both within- and across seasons. Consequently, the individual investments made to construct or maintain a burrow system benefit their own offspring, or siblings, over several breeding seasons.     

Spatial and Social Organization in a Burrow-Dwelling Lizard (Phrynocephalus vlangalii) from China

Shared ecological resources such as burrow complexes can set the stage for social groupings and the evolution of more complex social behavior such as parental care. Paternity testing is increasingly revealing cases of kin-based groupings, and lizards may be a good system to inform on the early evolution of sociality. We examined spatial and social organization in the lizard Phrynocephalus vlangalii from China and tested genetic relatedness (based on eight microsatellite DNA loci) between offspring and parents that shared burrow complexes. Adult males and females had similar spatial patterns: they overlapped most with members of the opposite sex and least with their own sex. Males in better body condition overlapped with more females, and both sexes showed high site fidelity. Most lizards used a single burrow, but some individuals used two or three burrows. While high site fidelity is consistent with sociality in lizards, juveniles did not preferentially share burrows with parents, and we documented only a few cases of parent-offspring associations through burrow sharing. We suggest that P. vlangalii conforms to a classical polygynous mating system in which the burrow forms the core of the male's territory and may be offered as an important resource for females, but this remains to be determined.