Male parent birds exert more effort to reproduce in two desert passerines

Background:Parental investment by birds is limited by the habitat environment,and a male parent increases its effort to reproduce in birds that live in high-altitude areas.Methods:A study of the reproductive behaviour of the Saxaul Sparrow(Passer ammodendri)and the Isabelline Shrike(Lanius isabellinus)was carried out at the Gansu An’xi Extremely Arid Desert National Nature Reserve in northwest China to determine the reproductive input of passerine species in desert habitats.Results:In Saxaul Sparrows,compared to the female parent,the male parent exhibited a significantly higher fre-quency of nest-defense behaviour(chirping and warning)during nesting,hatching and feeding periods.In addition,in comparison to the female parent,the male parent exhibited almost equal frequencies of nesting and incubation but fed nestlings significantly more times.Similar to the male sparrows,the feeding rates of the male Isabelline Shrikes were significantly higher than those of the females.The hatching rate and fledging rate of the Saxaul Sparrow on aver-age in this study were 81.99 and 91.92%,respectively,while those of the shrike were 69.00 and 96.53%,respectively.Conclusions:These two different passerine species living in the same desert environment exhibited the same trend in their reproductive investments.Adapting to desert environments is a strategy that may have evolved in passerines where male parent birds put more effort than females into reproduction to ensure high reproductive output.

Egg investment strategies adopted by a desertic passerine, the Saxaul Sparrow(Passer ammodendri)

Background:As one of the reproductive strategies adopted by bird species,variation in investment in egg production and its influencing factors are important and well-studied subjects.Intraclutch changes in egg size associated with laying order may reflect a strategy of"brood survival"or"brood reduction"adopted by female birds in different situations.Methods:We conducted field studies on the breeding parameters of the Saxaul Sparrow(Passer ammodendri)in Gansu Province,China from 2010 to 2017,to clarify the factors affecting the egg investment and reproductive performance of this passerine species.Results:Our results revealed significant differences in clutch size,egg size and the fledging rate between the first and second brood of Saxaul Sparrows and suggested that this typical desert species allocates more breeding resources to the more favourable second brood period,leading to greater reproductive output.Female body size presented a positive relationship with egg size,and male body size presented positive relationships with clutch size and hatchability.The females that started their clutches later laid more eggs,and hatchability and the fledging rate also increased with a later laying date in the first brood period.With successive eggs laid within the 5-egg clutches(the most frequent clutch size),egg size increased for the first three eggs and then significantly decreased.Conclusions:Our results indicate that female Saxaul Sparrows increased egg investment because of good quality of paired males and good environmental conditions.The intraclutch variation of egg size suggests that this species inhabiting an arid environment adopts a"brood reduction"strategy.

利用红外相机监测甘肃安西极旱荒漠国家级自然保护区鸟兽物种多样性

为了系统掌握甘肃安西极旱荒漠国家级自然保护区野生动物的种类、数量、分布以及种群动态变化趋势,我们于2017年8月至2019年9月,在保护区选取3个样地布设60台红外相机,对保护区兽类和鸟类多样性进行调查。红外相机累计观测29,147个工作日,采集独立有效照片11,134张。共观测到兽类6目10科18种,鸟类7目16科31种。国家I级重点保护野生动物有5种,国家Ⅱ级重点保护野生动物有11种。兽类中相对多度较高的物种有蒙古兔(Lepus tolai,RAI=12.749)、岩羊(Pseudoisnayaur,RAI=4.690)、北山羊(Caprasibirica,RAI=4.333)、蒙古野驴(Equus hemionus,RAI=3.163)、赤狐(Vulpes vulpes,RAI=2.601),分布最普遍的是赤狐和蒙古兔;鸟类中相对多度较高的物种有石鸡(Alectoris chukar,RAI=1.678)、岩鸽(Columba rupestris,RAI=1.142)、漠?(Oenanthe deserti,RAI=0.865)、赭红尾鸲(Phoenicurus ochruros,RAI=0.374)和沙?(Oenanthe isabellina,RAI=0.196),其中漠?和石鸡的分布最广。豺(Cuon alpinus)、石貂(Martes foina)、黄鼬(Mustela sibirica)和白唇鹿(Cervus albirostris)为保护区新记录物种,雪豹(Pantherauncia)也是保护区建立以来首次观测到。保护区人为干扰减少是造成物种新分布、数量增多的主要原因。

Limited gene flow and partial isolation phylogeography of Himalayan snowcock Tetraogallus himalayensis based on part mitochondrial D-loop sequences

Himalayan snowcock Tetraogallus himalayensis are distributed in alpine and subalpine areas in China. We used mi- tochondrial DNA control-region data to investigate the origin and past demographic change in sixty-seven Himalayan snowcock T. himalayensis. The fragments of 1155 nucleotides from the control region of mitochondrial DNA were sequenced, and 57 poly- morphic positions defined 37 haplotypes. A high level of genetic diversity was detected in all populations sampled and may be associated isolation of the mountains and habitat fragmentation and deterioration from Quaternary glaciations. In the phylogenetic tree, all haplotypes grouped into four groups： clade A （Kunlun Mountains clade）, clade B （Northern Qinghai-Tibetan Plateau clade）, clade C （Tianshan Mountains clade） and clade D （Kalakunlun Mountains clade）. We found a low level of gene flow and significant genetic differentiation among all populations. Based on divergence time we suggest that the divergence of Himalayan snowcock occurred in the middle Pleistocene inter-glaciation, and expansion occurred in the glaciation. Analysis of mtDNA D-loop sequences confirmed demographic population expansion, as did our non-significant mismatch distribution analysis. In conclusion, limited gene flow and a pattern of partial isolation phylogeographic was found in geographic populations of T. hima- layansis based on the analysis on mtDNA D-loop sequences [Current Zoology 57 （6）： 758-767, 2011].

Population structure and demographic history of the chukar partridge Alectoris chukar in China

Pleistocene climate fluctuations have shaped the patterns of genetic diversity observed in extant species. Although the effects of recent glacial cycles on genetic diversity have been well studied on species in Europe and North America, genetic legacy of species in the Pleistocene in north and northwest of China where glaciations was not synchronous with the ice sheet development in the Northern Hemisphere or or had little or no ice cover during the glaciations＇ period, remains poorly understood. Here we used phylogeographic methods to investigate the genetic structure and population history of the chukar partridge Alec- toris chukar in north and northwest China. A 1,152 - 1,154 bp portion of the mtDNA CR were sequenced for all 279 specimens and a total number of 91 haplotypes were defined by 113 variable sites. High levels of gene flow were found and gene flow esti- mates were greater than 1 for most population pairs in our study. The AMOVA analysis showed that 81% and 16% of the total genetic variability was found within populations and among populations within groups, respectively. The demographic history of chukar was examined using neutrality tests and mismatch distribution analyses and results indicated Late Pleistocene popula- tion expansion. Results revealed that most populations of ehukar experienced population expansion during 0.027 - 0.06 Ma. These results are at odds with the results found in Europe and North America, where population expansions occurred after Last Glacial Maximum （LGM, 0.023 to 0.018 Ma）. Our results are not consistent with the results from avian species of Tibetan Plateau, either, where species experienced population expansion following the retreat of the extensive glaciation period （0.5 to 0.175 Ma）