Detection of parasitizing coccidia and determination of host crane species, sex and genotype by faecal DNA analysis

In Japan, the three main crane species are the endangered red-crowned crane (Grus japonensis) inhabiting Hokkaido, the northernmost island of Japan; the vulnerable hooded crane (Grus monacha); and the vulnerable white-naped crane (Grus vipio). Both the hooded and white-naped cranes migrate in winter to Izumi in Kyushu, the southern island of Japan. In this study, we investigated the cranes and their coccidian parasites, through a targeted molecular approach using faecal DNA to develop a noninvasive method for infectious disease research. To determine the origin of noninvasively collected faecal samples, host species were identified by sequencing a region of approximately 470 bp of the mitochondrial 16S ribosomal RNA gene in the faecal DNA. Furthermore, to avoid sample redundancy, individual determination was performed by fragment analysis using microsatellite and sex-linked markers. For microsatellite genotyping, previously reported markers and markers isolated in this study were examined, and seven loci for red-crowned cranes, eight for hooded cranes and six for white-naped cranes displayed polymorphisms. A low error rate was demonstrated by comparing microsatellite data generated from faecal DNA samples with that generated from feather DNA samples, indicating a high reliability. Polymerase chain reaction-based capillary electrophoresis (PCR-CE), employing genetic markers in the second internal transcribed spacer (ITS2) of nuclear ribosomal DNA, was employed to detect crane coccidia. The sensitivity of detection of PCR-CE using faecal DNA was inferior to that with traditional microscopy; however, our results suggest that PCR-CE can depict crane coccidia diversity with higher resolution and it is a useful tool to characterize community composition of coccidia in detail.     

A simple population viability analysis of Tancho (Grus japonensis) in southeastern Hokkaido, Japan

We employed population viability analysis to estimate future population trends and extinction risk of Tancho, the Japanese or red-crowned crane (Grus japonensis). The stage matrix was based on 15 years of data collected by counting the number of wintering cranes and following the survivorship of banded cranes. The accidental death rate was estimated from the number of dead or seriously injured cranes collected in the Kushiro municipal zoo. Consequently, the accidental death rate was found to increase each year at 0.072% per year during the recent 14 years and 0.132% per year during final 6 years. The carrying capacity (K) was estimated from the mean mire area within the territory of a breeding pair and the geographic information system data in southeastern Hokkaido. Accordingly, K was estimated to be 1,659 in this area. Using the stage matrix, accidental death rates and K (and 20%-lower K), the simulation was conducted under three conditions: (1) the increase of accidental death, (2) the limitation of carrying capacity, and (3) the concurrent occurrence of carrying capacity limitation and accidental death increase. As a result, the extinction probability during 100 years was zero, although the accidental death rate increased at the current rate of 0.132% per year. Therefore, by artificial feeding in winter, the Japanese population of Tancho reached the adequate level, which seems sustainable unless some catastrophic factors seriously damage the population. To raise the tolerance to catastrophic factors, we discuss the probability of their distributional expansion to western or northern Hokkaido and even to Honshu.     

鄱阳湖越冬白鹤肠道微生物群落结构及功能预测分析

【目的】分析鄱阳湖越冬白鹤在人工生境中肠道微生物群落组成和代谢功能特征。【方法】利用16S rRNA基因高通量测序技术比较藕田和稻田2种不同人工生境鄱阳湖越冬白鹤肠道微生物群落组成和重建未观察到的状态(phylogenetic investigation of communities by reconstruction of unobserved states, PICRUSt)进行功能预测。【结果】稻田白鹤肠道微生物α多样性(Ace、Chao1、Shannon和Simpson指数)高于藕田白鹤,但未达到显著水平(P>0.05)。基于Binary-Jaccard距离矩阵的β多样性分析发现2种人工生境的白鹤肠道微生物群落结构差异显著(R²=0.312, P<0.05)。不同人工生境鄱阳湖越冬白鹤肠道微生物组成存在差异,藕田白鹤肠道微生物的优势菌属是土孢杆菌属、罗布西亚属和苏黎世杆菌属;稻田白鹤肠道微生物的优势菌属是乳酸杆菌属、里氏杆菌属和球菌属。线性判别分析[line discriminant analysis (LDA) effect size, LEfSe]分析发现乳杆菌科、乳酸杆菌属、苏黎世杆菌属等具有较强发酵代谢碳水化合物能力的微生物在2种人工生境下差异显著。PICRUSt功能预测表明鄱阳湖越冬白鹤肠道微生物与新陈代谢、基因信息处理、环境信息处理和人类疾病等功能相关,在level 1水平上,有5类代谢通路具有显著性差异(P<0.001)。【结论】两种人工生境中鄱阳湖越冬白鹤肠道微生物组成和群落特征差异较大,可能是由于同域觅食鸟类的种类、数量以及食物来源的不同。同时,PICRUSt功能预测揭示了不同人工生境中鄱阳湖越冬白鹤肠道微生物功能基因丰度的显著差异,表明白鹤可以通过调整自身肠道微生物组成来适应不同人工生境食物资源的变化带来的挑战。本研究对不同人工生境下白鹤肠道微生物的组成和功能潜力的研究结果可以为鄱阳湖越冬白鹤肠道微生物的研究提供一定依据,对于白鹤的保护和制定管理策略具有一定的参考价值和现实意义。     

黑颈鹤种群动态模型

本研究据已收集到的数据,用非参数统计方法确定了黑颈鹤种群的性比为1:1,避免了大量取样。根据黑颈鹤的特点,我们将其种群分成4个年龄组,并求出了各年龄组的存活率和繁殖率,据此建立了描述黑颈鹤种群动态的数学模型。用模型计算得出在乌蒙山区越冬的黑颈鹤种群的自然增长率为1.85‰;理想的种群结构为幼鹤、亚成鹤、成鹤、老鹤分别占总数的15.5％、21.5％、60.2％、2.8％,最后预测了乌蒙山黑颈鹤种群在1988～2000年越冬期的数量。1989年1月经实地调查该种群总数为310只,而预测值为303只,误差约2％。     

Satellite tracking of the migration of the red-crowned crane Grus japonensis

Autumn migration routes of red-crowned cranes, Grus japonensis, from two continental east Asian sites were documented in detail by satellite tracking. Two routes were identified: a 2200km western route from Russias Khingansky Nature Reserve to coastal Jiangsu Province, China; and a 900km eastern route from Lake Khanka (Russia) to the Korean Peninsula and the Demilitarized Zone. The most important rest-sites were identified as Panjin Marsh (China), coastal mudflats south-east of Tangshan City (China), the Yellow River mouth (China), Tumen River mouth (North Korea/China/Russia), Kumya (North Korea) and Cholwon (Korean DMZ). Movements within the wintering range were also recorded, including complex commuting between sites by individual cranes and patterns of daily movements within sites. These data should prove useful for conservation of the flyway.     

鄱阳湖4种鹤类集群特征与成幼组成的时空变化

2014年10月—2015年4月,采用样点法对鄱阳湖45个样点的白鹤(Grus leucogeranus)、白头鹤(G.monacha)、白枕鹤(G.vipio)和灰鹤(G.grus)的集群大小、集群类型和成幼组成进行调查。结果显示,白鹤的平均集群大小(23.86±10.26)只(集群数N=104),白头鹤(6.42±1.63)只(N=98),白枕鹤(6.09±2.55)只(N=105),灰鹤(5.55±1.26)只(N=246)。仅白头鹤中期集群大小显著小于后期,其余鹤类各时期及灰鹤各地区的集群大小差异不显著。鄱阳湖鹤类的集群大小并不符合警戒行为对集群大小的预测,生境质量差异可能是影响鄱阳湖鹤类集群大小的主要原因之一。4种鹤类均在1—5只个体的小集群中出现频度最高。白鹤在35只个体集群中的个体比例最高,而白头鹤、白枕鹤和灰鹤在1—5只个体集群和35只个体集群均有较高的个体比例。白鹤、白头鹤、白枕鹤和灰鹤均以家庭群为主,其家庭群所占比例分别为(64.29%,总集群数N=98)、(71.91%,N=89)、(70.77%,N=65)和(63.11%,N=206)。鄱阳湖鹤类以家庭群为主表明,保证充足的食物供应可能比花费更多的觅食时间更为重要。白鹤家庭群以2成1幼为主(65.08%),白头鹤(51.56%)、白枕鹤(52.17%)和灰鹤(47.69%)以2成为主。白鹤、白头鹤、白枕鹤和灰鹤群体的幼鸟比例分别为12.27%(个体数N=1695)、14.42%(N=416)、16.59%(N=229)和20.46%(N=655)。2成2幼集群比例极低表明,白鹤家庭同时抚养2个幼鸟成活的难度较其它3种鹤类大。4种鹤类在各时期的幼鸟比例差异不显著。在灰鹤个体数较多的3个地区中,都昌候鸟省级自然保护区(25.25%)和东鄱阳湖国家级湿地公园(25.14%)的幼鸟比例分别显著和极显著地高于鄱阳湖国家级自然保护区(14.24%)。鄱阳湖白鹤的幼鸟比例多年来均处于较低水平,白头鹤的幼鸟比例较2012—2013年冬季明显下降,灰鹤和白枕鹤种群可能处于稳定或增长状态。     

Assessing the above‐ground biomass of a complex tropical rainforest using a canopy crane

Abstract Current estimates of the total biomass in tropical rainforests vary considerably; this is due in large part to the different approaches that are used to calculate biomass. In this study we have used a canopy crane to measure the tree architectures in a 1 ha plot of complex mesophyll vine forest at Cape Tribulation, Australia. Methods were developed to measure and calculate the crown and stem biomass of six major species of tree and palm (Alstonia scholaris (Apocynaceae), Cleistanthus myrianthus (Euphorbiaceae), Endiandra microneura (Lauraceae), Myristica insipida (Myristicaceae), Acmena graveolens (Myrtaceae), Normanbya normanbyi (Arecaceae)) using the unique access provided by the crane. This has allowed the first non‐destructive biomass estimate to be carried out for a forest of this type. Allometric equations which relate tree biomass to the measured variable ‘diameter at breast height’ were developed for the six species, and a general equation was also developed for trees on the plot. The general equation was similar in form to equations developed for tropical rainforests in Brazil and New Guinea. The species equations were applied at the level of families, the generalized equation was applied to the remaining species which allowed the biomass of a total of 680 trees to be calculated. This has provided a current estimate of 270 t ha⁻¹ above‐ground biomass at the Australian Canopy Crane site; a value comparable to lowland rainforests in Panama and French Guiana. Using the same tree database seven alternative allometric equations (literature equations for tropical rainforests) were used to calculate the site biomass, the range was large (252–446 t ha⁻¹) with only three equations providing estimates within 34 t ha⁻¹ (12.5%) of the site value. Our use of multiple species‐specific allometric equations has provided a site estimate only slightly larger (1%) than that obtained using allometric equations developed specifically for tropical wet rainforests. We have demonstrated that it is possible to non‐destructively measure the biomass in a complex forest using an on‐site canopy crane. In conjunction the development of crown maps and a detailed tree architecture database allows changes in forest structure to be followed quantitatively.     

Specialization of rainforest canopy beetles to host trees and microhabitats: not all specialists are leaf‐feeding herbivores

Reliable estimates of host specificity in tropical rainforest beetles are central for an understanding of food web dynamics and biodiversity patterns. However, it is widely assumed that herbivores constitute the majority of host specific species, and that most herbivore species feed on leaves. We tested the generality of this assumption by comparing both plant host‐ and microhabitat‐specificity between beetle communities inhabiting the foliage (flush and mature), flowers, fruit, and suspended dead wood from 23 canopy plant species in a tropical rainforest in north Queensland, Australia. Independent of host tree identity, 76/77 of the most abundant beetle species (N ≥ 12 individuals) were aggregated on a particular microhabitat. Microhabitat specialization (measured by S_m and Lloyd's indices) was very high and did not differ between flower and foliage communities, suggesting that each newly‐sampled microhabitat has a large additive effect on total species richness. In accordance with previous studies, host specificity of foliage‐inhabiting beetles was most pronounced among herbivorous families (Curculionidae, Chrysomelidae). By contrast, host specificity among flower‐visitors was equally high among herbivorous and nonherbivorous families (e.g. Nitidulidae, Staphylinidae, Cleridae). Effective specialization (F_T) measures showed that traditional correction factors used to project total species richness in nonherbivorous groups fail to fully capture diversity in the flower‐visiting beetle fauna. These results demonstrate that host specialization is not concentrated within folivores as previously assumed. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 215–228.     

Species conservation on human-dominated landscapes: the case of crowned crane breeding and distribution outside protected areas in Uganda

Species primarily dependent on habitats outside protected areas have to cope with the direct pressure of human utilization or harassment, and the indirect pressure of habitat modification. In Uganda, wetlands mainly used by cranes occur mostly outside protected areas. The country's wetlands are however under heavy modification, and this and other pressures are thought to have reduced crane populations to 10–30% of the number in the early 1970s. From January 2005 to January 2006, we assessed the status of crane breeding and distribution in the country. Breeding and foraging sites were assessed through a nationwide newspaper survey, and visits to wetlands. We established occurrence of 21 nests during the study period, and crane use of 27 out of 30 districts surveyed. Crane harassment and trapping were common during breeding, as was crop damage by cranes. This is the first attempt to show the distribution of crane breeding outside protected areas throughout the country. In addition to maintaining suitable breeding habitat, survival of cranes in Uganda lies in part in community engagement and punishing crimes related to hunting and destruction of nests.     

Comparison of lepidopteran larval communities among tree species in a temperate deciduous forest, Japan

Abstract.  1. The enormous diversity of phytophagous insects in forest canopies is hypothesised to be supported by the number of herbivorous species per host tree species or host specificity. It is therefore necessary to examine the effect of host plant species on compositional changes in the herbivore communities.
2. The lepidopteran larval communities were examined in the canopies of 10 tree species in a temperate deciduous forest of Japan. The phylogeny and leaf flush phenology of host plant species were taken into account as factors affecting the herbivore community assembly.
3. Examination of seasonal changes in the larval community structures on each tree species showed that larval species richness, abundance, and evenness decreased significantly from spring to summer. Larval species richness and abundance were characterised by family-level phylogenetic differences among tree species, whereas evenness was determined at a higher taxonomic level.
4. Compositional changes in the larval communities among tree species showed a remarkable pattern, with a phylogenetic effect at a high taxonomic level in spring, similar to evenness, but a phenological effect in summer. This suggests that host specificity could support the lepidopteran larval diversity in spring.
5. These results suggest that the differences in host utilisation of the herbivore, which reflects the phylogenetic effect of the host plants, can be important as a factor affecting the diversity of lepidopteran larval communities in temperate forests.