首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
    
Abstract

A new distribution locality for the Forest Dormouse, Dryomys nitedula, is reported from Ashrafiat Al Wade in the Barada River valley, northwest of Damascus. The specimens are morphologically similar to the Arabian and Turkish populations. Some ecological and biological aspects are discussed.  相似文献   

2.
3.
4.
The family Camelidae has been present in Eurasia since the latest Miocene, and several species are recognized, but their evolution is poorly known. The region of El Kowm, central Syria, includes several sites spanning the Early to Late Pleistocene and provides the only abundant fossil record of camelids in the Middle East. Our preliminary results show that several species are present over the sequence, revealing some surprising evolutionary trends.  相似文献   

5.
    
Abstract

Breeding of the Desert Wheatear (Oenanthe deserti) was confirmed in south-east Turkey in 1985.  相似文献   

6.
    
Abstract

The breeding cycle of three pairs of the Syrian Woodpecker, Dendrocopos syriacus, was studied in the Gaza Strip. The distribution, nest, egg and egg-laying, incubation, development of the young and some behavioural aspects are described.  相似文献   

7.
    
The population biology of Nematopalaemon schmitti in the Ubatuba region on the northern coast of the state of São Paulo was characterized through analyses of the length-frequency distribution, sex ratio, reproductive period, and juvenile recruitment. The specimens were caught monthly from January 1998 to December 1999, from a shrimp boat equipped with double-rig trawl nets. A total of 1073 specimens were analyzed, and the sex and carapace length (0.1?mm) of each individual were noted. The analyzed specimens consisted of 152 juveniles, 437 adult males, 296 adult females, and 188 ovigerous females (OFs). The monthly distribution of N. schmitti by size classes revealed a stable population structure, with both juveniles and adults continuously present. This population showed a unimodal distribution; however, bimodality was identified in June 1998 and 1999 for males, and June 1998 and July 1998 and 1999 for females, probably related to recruitment pulses of juveniles. Sexual dimorphism was indicated by the presence of females in the larger size classes, probably because of their growth rate. The proportion between males and females differed from 1?:?1 in certain size classes and seasons of the year (χ 2,?p?<?0.05); in some situations, the females were more abundant than the males, or vice versa. No significant relationship was detected between the seasonal mean temperatures of the bottom water and the percentages of OFs and young, or for the relationship between these two groups (Spearman, p?>?0.05). The continuous presence of OFs and young in the population suggests a pattern of continuous reproduction for N. schmitti in the Ubatuba region.  相似文献   

8.
From observations of the spatial distribution of humpback whales in the Mexican Pacific between 1981 and 1986, it is possible to recognize four subregions: 1) the southern coast of Baja California; 2) the northern Gulf of California, including the Midriff Islands; 3) the mainland coast of Mexico, including the Isla Isabel and Islas Tres Marias and 4) the Revillagigedo Archipelago. The seasonal distribution of whales near the Mexican mainland and the Revillagigedo Archipelago extends from November to May and is similar to that of other winter breeding grounds, including the Hawaiian Islands. Along the southern coast of Baja California, whales have been observed from September to April, possibly indicating a shorter migratory route. In the northern Gulf of California, however, humpback whales have been reported throughout the year and are occasionally observed feeding during both summer and winter months. The degree of individual movement between the four subregions is still unknown. The number of individual humpback whales identified photographically in recent years suggests that there ate more whales in the Mexican Pacific than previously reported.  相似文献   

9.
Abstract

Local differences in species richness and abundance of buprestid beetles were studied at the microsite “Evolution Canyon”, Lower Nahal Oren, Mt. Carmel, Israel, a model conceived for studying biodiversity evolution in a microcosm of life in nature. 39 species were collected at the microsite, and species richness was higher on the more arid and microclimatically stressful and variable south-facing slope than on the milder, more humid and relatively homogeneous north-facing slope. The interslope differences in abundance were significant in five species. New larval host plants were added for nine species, as well as new data about the regional distribution of buprestid beetles. The results support earlier conclusions in various groups of organisms across phylogeny.  相似文献   

10.
2014年4-10月,利用焦点个体取样法与连续记录法对北京市野生动物救护繁育中心饲养的褐马鸡Crossoptilon mantchuricum繁殖期以及非繁殖期的行为时间分配和活动节律进行了研究。统计了不同性别与不同季节的行为时间分配差异。在繁殖期,雌性褐马鸡的取食时间大于雄性,而雄性褐马鸡的移动、警戒行为时间大于雌性。在非繁殖期,雌雄褐马鸡行为差异变小,但雄性褐马鸡的警戒行为仍然较多。  相似文献   

11.
在发情期,对动物行为时间分配和活动节律的认识将有助于濒危动物繁育质量的提高。大熊猫为季节性单次发情动物,雄性发情期可持续30 d左右,而雌性大熊猫为几天至十几天,高峰期仅为1~3 d,且有与雄性不同步发情的现象。因此,进行发情期行为学方面的研究则显得尤为重要。采用瞬时扫描取样法和全事件记录法,于2013年3月1日—4月30日对成都大熊猫繁育研究基地的8只发情期大熊猫进行行为时间变化和活动节律研究,每只每周记录2 d数据。结果表明:休息行为是发情期最主要的行为方式(雄性约46%,雌性约53%),其次是摄食和运动行为,而探究、求适和发情行为则较少,发情行为主要出现在00:00—03:00、09:00—11:00和15:00—17:00等3个时段,可配对交配;发情期雌雄个体在休息、求适、运动和发情行为上的差异有高度统计学意义(P<0.01),在探究行为上的差异有统计学意义(P<0.05),而在摄食行为上的差异则无统计学意义;且发情、探究行为与运动行为呈显著正相关(P<0.01)。对发情期圈养大熊猫昼夜活动行为的研究将为大熊猫的人工繁育及其配种提供行为学方面的理论依据。  相似文献   

12.
13.
    
Our understanding of life history evolution has benefited from debates regarding the underlying causes, and geographic ubiquity, of spatial patterns in avian clutch sizes. Past studies have revealed that birds lay smaller clutch sizes at higher elevation. However, in most previous studies, investigators have failed to adequately control for elevational differences in breeding phenology. To better understand the elevational gradient in avian clutch size, we need to know how clutch size changes across the entire elevational breeding range of a species (i.e., the shape of the relationship between elevation and clutch size), and whether the elevational gradient in clutch size is merely an artifact of elevational gradients in breeding phenology or breeding season length. We examined the relationship between breeding elevation and clutch size of Red‐faced Warblers (Cardellina rubrifrons) along a 1000‐m elevational gradient in Arizona. Our objectives were to determine how clutch size changed with elevation, and if the relationship between clutch size and elevation merely reflected elevational changes in breeding season length or phenology. The proportion of 5‐egg clutches decreased and the proportion of 3‐ and 4‐egg clutches increased non‐linearly with increasing elevation, even after controlling for the elevational gradient in nest initiation date. Thus, average clutch size declined across the elevational breeding range of Red‐faced Warblers, but this decline was not due to elevational variation in breeding phenology. Timing of breeding changed, but the duration of the breeding season did not change appreciably across the elevational gradient. Hence, elevational differences in breeding season length or breeding phenology cannot explain why Red‐faced Warblers (and perhaps other birds) breeding at higher elevations have smaller clutches.  相似文献   

14.
    
The Persian Long-tailed Desert Lizard, Mesalina watsonana, is one of the most common and most widely distributed lizards on the Iranian Plateau extending from Iran to Pakistan and Afghanistan. The species is frequently encountered in various types of habitats. We collected over 600 distributional records from available literature, museum collections, and our own field work and used bioclimatic and land cover characteristics to develop a model of potential distribution for M. watsonana. According to the model, the most important factors limiting the distribution of M. watsonana are: precipitation in wettest quarter exceeding 250–300 mm, precipitation in coldest quarter lower than 40 mm and exceeding 250 mm, altitudes above 2500 m and slopes steeper than 10.5°. The model suggests that most of the Iranian Plateau is suitable for the species except for some isolated areas such as the Dasht-e Kavir and Dasht-e Lut deserts in Iran, Helmand basin in Afghanistan, the Karakum Desert in Turkmenistan, the western Chagai-Kharan deserts of Pakistani Balochistan, and Thar and Cholistan deserts in eastern Pakistan. The most important factor in these regions appears to be the extremely low rainfall during coldest quarter of the year. The outer boundary of the distribution of M. watsonana follows important biogeographic barriers that are also clearly delimited by climatic conditions.  相似文献   

15.
16.
    
  相似文献   

17.
Abstract

Even in areas with a rich insect life inhabited by several species of swallows and swifts, different preferences and species assemblages during aerial hunting can be observed. Geographical differences in distribution and abundance, different habitat preferences, time of season and day as well as different range of hunting flights will influence local species assemblages and coexistence during aerial hunting.  相似文献   

18.
    
Abstract

The Lake of Köyceg¯iz (Köyceg¯iz Gölü) in southwest Turkey is influenced by several external factors such as sulfuric springs, :Mediterranean seawater and a relatively strong changing wind. These give rise to an exceptional hydrochemistry and hydrophysics, which are reflected in the phyto and zooplankton. The complicated layer structure of the lake is determined more by chemical gradients than by temperature. The water body is divided in two layers of differing hydrology. The upper layer is subject to full circulation while the lower one is strictly stratified by chemical gradients caused by the sulfuric sources and an influx of-Mediterranean water. The lake can be classified as meromictic. Subsurface freshwater springs may well influence the system, but to a lesser degree. Phyto- and zooplankton are characterized by a limited number of species and a low biomass. ’This is due to a very thin euphotic zone as well as the brackish character of the lake water.  相似文献   

19.
20.
Abstract

A new record of the Grey-headed Woodpecker in north-eastern Turkey shows, together with published results, that the species apparently is distributed in low density over the whole Black Sea region of Turkey.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号