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1
Abstract:
Background 

Accurately assigning hatchlings to the eggs from which they hatched is a prerequisite to understanding how the composition and environment of eggs affect the growth and survival of nestlings. Correctly assigning hatchlings to their eggs can be a challenging endeavor, however, because multiple eggs within the same clutch can hatch at essentially the same time. Egg and hatchling mass are highly correlated in most bird species, and thus assigning eggs to hatchlings using their relative mass (e.g., matching the heaviest hatchling to the heaviest candidate egg) could prove extremely useful.

Methods 

To assess its potential utility, I applied relative mass assignment (RMA) retrospectively to a dataset of 133 Common Grackle (Quiscalus quiscula) nests in which all egg-hatchling dyads were determined unequivocally.

Results 

I found that RMA correctly assigned approximately 90% of hatchlings to their eggs when 2-4 hatchlings were present between checks. The number of nests in which hatchlings could not be assigned to their egg, however, increased monotonically from 13 to 46 to 78% for nests containing 2, 3, and 4 hatchlings, respectively, due to the greater likelihood that the mass of hatchlings or their candidate eggs was identical.

Conclusions 

Although RMA correctly identified the vast majority of egg-hatchling dyads, researchers should use this method with caution, because it will always inflate positive egg-size effects and thus could potentially result in erroneously reporting significant effects.

2
Abstract:

This paper reviews the population trends and threats for the 15 species of cranes, and comments on conservation priorities for the family as a whole. Cranes occur on five continents, with greatest diversity in East Asia (nine species) and Sub-Saharan Africa (six species). Eleven crane species are threatened with extinction according to the IUCN Red List, including one species Critically Endangered, three species Endangered, and seven species Vulnerable. Of the four species of Least Concern, population sizes for the Demoiselle (Anthropoides virgo) and Brolga (Grus rubicunda) are not well known but these species are declining in some areas. The Sandhill (G. canadensis) and Eurasian Cranes (G. grus) are the most abundant cranes and have rapidly increased in part due to their flexible selection of foraging habitats and use of agriculture lands and waste grain as a food source. Status for six species—Grey Crowned (Balearica regulorum), Blue (Anthropoides paradise), Black-necked (G. nigricollis), Red-crowned (G. japonensis), Sandhill, and Siberian (G. leucogeranus)—are summarized in more detail to illustrate the diversity of population shifts and threats within the crane family. A crane threat matrix lists the major threats, rates each threat for each species, and scores each threat for the crane family as a whole. Four of the five greatest threats are to the ecosystems that cranes depend upon, while only one of the top threats (human disturbance) relates to human action directly impacting on cranes. Four major threats are discussed: dams and water diversions, agriculture development, crane trade, and climate change. Conservation efforts should be strongly science-based, reduce direct threats to the birds, safeguard or restore habitat, and strengthen awareness among decision makers and local communities for how to safeguard cranes and wetlands. Especially for the most severely threatened species, significantly stronger efforts will be needed to incorporate our understanding of the needs of cranes and the ecosystems they inhabit into decisions about agriculture, water management, energy development and other human activities.

3
Abstract:

The systematics of the avian superfamily Sylvioidea are reviewed, focusing on studies of relationships among families and within genera, more superficially on taxonomic studies at the species level. For the families Bernieridae and Phylloscopidae, new analyses based on already published sequence data are presented. Our understanding of relationships has been vastly improved in recent years due to a large number of molecular studies. However, the relationships among the different families remain largely obscured, probably mainly as a result of rapid divergence of the different primary lineages (families). Also, species level taxonomy has been much improved in recent years due to a large number of studies applying molecular markers and/or vocalizations and other life-history data. It seems likely that the number of species will continue to increase, as new groups are being studied with modern integrative methods.

4
Abstract:

The field biology of the Grey Francolin (Francolinus pondicerianus) was studied in 2009 in an agro-ecosystem of the Pothwar area, an important range of its distribution in Pakistan. The bird density was estimated as 1.59±0.39 (mean±standard error) birds per ha in crop fields and 0.87±0.14 birds per ha in forest tracks, with some seasonal fluctuations in its habitat. All bird nests were located on the ground in vegetation mainly comprised of Desmostachia bipinnata, Acacia modesta, Imperata cylindrical, Zizipus jujuba and Euphorbia spp. Egg laying was recorded during the spring and summer months, with a mean egg laying span of 6±0.36 days (range 5-7 days) and a mean clutch size of 7±0.36 (range of 6-8 eggs). The mean incubation period was 20.6±0.50 days (range 19-22 days). Out of a total number of 42 eggs recorded, 32 hatched (76.19% success) with a mean hatching rate of 5.33±1.22 eggs per clutch. The fledgling success was estimated as 3.83±0.83 per clutch (63.08%). The species was found to be omnivorous and euryphagus in its feeding habit. There were 10 identifiable food items in the diet of the species, consisting of seven plant species (Pennisetum typhoideum, Sorghum bicolor, S. halepense, Prosopis juliflora, Phaseolus radiates, Carthemus axycantha and Acacia sp.), two insect species (Coptotermes formosanus and Formica rufa) and one grit.

5
Abstract:

The Red-crowned Crane (Grus japonensis) is a globally endangered species. Although this species has received much attention by scientists, conservationists and the general public, the continental population of the Red-crowned Crane continues to face serious threats which affect not only its population dynamics but also its breeding and wintering habitats. Habitat loss and deterioration are the main causes of the decline of its population. With the massive loss of habitats in all parts of its range-breeding, stopover and wintering grounds-the cranes have been forced into crops and farmlands where cranes are more vulnerable to human activities, such as poisoning the cranes and conflicts with farmers. From our review of studies done over 30 years, the eastern flyway subpopulation has been stable or slightly increasing and the western flyway subpopulation of the Red-crowned Crane has sharply declined in recent years. The wintering population for the western flyway has declined from over 1100 to less than 500 birds. Not only is the size of the population reduced to less than 50%, but most recently the decline has occurred with frightening speed, by 50-150 birds per winter. The current wintering range for the west flyway is only about 8% of its extent in the 1980s. Urgent actions for habitat protection, law enforcement and education need to stop the declining trend for this species.

6
7
Abstract:

In undertaking regular surveys on those waterbirds appearing on Fujian coast and on offshore islands, people of Xiamen Bird-watching Society had observed, for five times during 2007 -2009, three marked individuals of the Roseate Tern (Sterna dougallii) on Caiyu Archipelago of Caiyu Archipelago of south Fujian offshore; it is now quite certain that the leg-flags were marked on birds by people of the Australasian Wader Studies Group (AWSG) and at least one of those leg-flagged terns is already over six or seven years old by the time of re-sighting; this record might be useful and helpful for further estimating the life circle as well as the length of generation of those gulls and terns appearing and breeding along the SE Chinese coast, such as the Black-tailed Gull (Larus crassirostris), the Great Crested Tern (Sterna bergii), the Chinese Crested Tern (S. bernsteini), etc.

8
Abstract:

A study of the population status of and threats to the Black-winged Lovebird (Agapornis taranta) was carried out from September 2008 to February 2009 in Entoto Natural Park (ENP) and in Bole Sub-City, Addis Ababa, Ethiopia. A point transect count technique was employed to examine the status of the lovebirds. An average total of 58 birds was recorded of which 46 were counted in Bole Sub-City and 12 in Entoto Natural Park areas. The maximum number recorded during our census was 57 in the dry season and 15 in the wet season in Bole Sub-City and Entoto Natural Park, respectively. The ratio of adult males to adult females in Entoto Natural Park was 1:0.71 and 1:0.60, and 1:0.76 and 1:0.78 in Bole Sub-City during both wet and dry seasons, respectively. The seasonal variation and difference in sex ratios between males and females was not significant (p > 0.05) at either of the study sites. The threat for the Black-winged Lovebird or other birds in Entoto Natural Park is due to the fragmentation of natural habitats, thus decreasing food sources, owing to the domination of eucalyptus (Eucalyptus globulus) trees in the area. Grazing by livestock, intensive farming practices and deforestation by the local community have contributed greatly to the degradation of the land resulting in erosion, thus devastating the habitat of the Natural Park. The vegetation cover of Entoto Natural Park and urban gardens should be managed effectively for the survival of the avian fauna of the area.

9
Abstract:

In this exposé we provide the first review of host use by brood parasitic cuckoos in a multiple-cuckoo system in China, based on our own long-term field data and a compilation of observations obtained from the literature. In total, we found that 11 species of cuckoos utilized altogether 55 host species. These hosts belong to 15 families, in which Sylviidae, Turdidae and Timaliidae account for 22.6%, 20.8% and 17.0% of parasitism records, respectively. The Common Cuckoo (Cuculus canorus) had the widest range of host species, accounting for 45.5% of the total number of parasitized species (25 in 10 families) of all parasitism records and is the most frequent brood parasite in the country. Cuckoo species differed in their egg coloration and the extent of egg polymorphism with most of them, e.g. the Common Cuckoo, the Lesser Cuckoo (C. poliocephalus) and the Plaintive Cuckoo (Cacomantis merulinus) laying well mimetic eggs with respect to their hosts based on human being's visual observations, while others such as the Large Hawk-cuckoo (C. sparverioides), the Himalayan Cuckoo (C. saturatus) and the Asian Emerald Cuckoo (Chrysococcyx maculatus) usually laid non-mimetic eggs. The use of cuckoo hosts and egg color variation in China are compared with those in other parts of their ranges in Asia.

10
Abstract:

We use the term "basal birds" for a relatively small number of primitive fossil birds that fall outside the major clade Ornithothoraces, which includes both modern birds and enantiornithines. Eight genera and twelve valid species have been reported from China in the last 15 years, whereas Archaeopteryx lithographica remains the only basal bird to have been described from non-Chinese specimens (although confuciusornithid material is apparently present in North Korea). Here we briefly review the Chinese basal birds and their anatomy, phylogeny and ecology. Chinese fossils have contributed extensively to scientific understanding of early avian evolution, demonstrating collectively that basal birds were generally relatively large and morphologically and ecologically quite diverse. Although some significant uncertainties remain, particularly with respect to the relative phylogenetic positions of Jeholornis, Sapeornis and Zhongornis, an increasingly clear picture of the first stages of avian evolution is emerging from the Chinese fossil record.

11
Abstract:

Fisher's theory predicts equal sex ratios at the end of parental care if the cost associated with raising offspring of each sex is equal. However, sex ratios have important evolutionary consequences and are often biased for many factors. Reported sex ratios are often biased in raptors, which display various degrees of reversed sexual dimorphism, but there seems no consistent pattern in their offspring sex ratios. In this study, we investigated the offspring sex ratio of the Eurasian Kestrel (Falco tinnunculus) and tested whether the patterns of biased sex ratios were related to laying order, egg mass, hatching order, laying date or clutch size. The brood sex ratio of the Eurasian Kestrel (male) in eggs was 47.0%, not statistically biased from 0.5, but in fledglings it was 40.8%, significantly biased from 0.5 (p=0.029). At population level, both primary and secondary sex ratios did not depart from parity. We found that clutch size and egg mass affected the secondary brood sex ratio, i.e., the larger the clutch size, the larger the number of males and eggs producing sons were heavier than eggs producing daughters. Laying date affected both the primary and secondary sex ratios, and laying earlier is associated with a greater proportion of males.

12
Abstract:

Brood parasitic birds constitute a model system for the study of coevolution. Such parasites are unique by having evolved unusually thick eggshells for their body size. Thick eggshells have been hypothesized to evolve as 1) a means of preventing damage to parasite eggs when the brood parasite lays its egg at a distance from the host clutch (the laying damage hypothesis); 2) a consequence of host puncture ejection (the puncture resistance hypothesis); 3) a means for the brood parasite to allocate calcium to development of a disproportionately large skeleto-muscular system in evicting parasite chicks (the chick vigour hypothesis); or 4) a means of protecting the cuckoo embryo from microorganisms in the nest of the host (the anti-bacterial protection hypothesis). Here we review the literature studying the evolutionary mechanisms promoting thick eggshells in avian brood parasites,and provide proposals for future studies to test their validity. Available data are insufficient to rigorously test exclusive predictions and assumptions of these not necessarily exclusive hypotheses,although the laying damage and the puncture resistance hypotheses seem to currently be the most well supported alternatives. We discuss how quantification of rejection modes (grasp ejection,puncture ejection and desertion) may disclose the validity of the puncture resistance hypothesis,and finally we provide perspectives for future research on testing this specific hypothesis.

13
Abstract:

The primer pair sex1/sex2, which can be widely applied for sex identification in Galliform species, was used to determine the sex of 17 Passeriform species. As CHD-W fragments tended to be preferentially amplified, which may cause unnecessary misidentification in bird species with little difference between CHD-Z and CHD-W, we modified sex1 and sex2, obtaining sex1' and sex-mix respectively. Primer sets were then recombined to conduct sex identification. After testing several Passeriforme birds of known sex, we found that the primer pair sex1'/sex2 was better at limiting the preferential amplification of CHD-W fragments. As they are being frequently used in sex allocation study of Aegithalos concinnus and song learning research of Lonchura striata, we can expect more applications of this primer pair to further studies in Passeriformes.

14
Abstract:

The Great Bustard (Otis tarda) world population is estimated to be 44100-57000 individuals in 2010, of which about 57-70% occur in Spain, 15-25% in European Russia, 4-10% in China, Mongolia and south-eastern Russia, 3-4% in Portugal, 3% in Hungary, 1-2% in Turkey, and smaller numbers in ten other countries. The reliability of current censuses and estimates may be described as high for a large fraction of the world population (67-75%), and low for the remaining 25-33% (including Russia, Mongolia, China, Turkey, Ukraine, Iran and Kazakhstan). In spite of continued declines reported for some countries (e.g., Turkey, Iran, China), the present survey suggests that total numbers have not significantly decreased worldwide during the last decade, as opposed to the globally declining trend currently assumed. This is due to a large fraction of the world total living in countries whose overall surveys are apparently stable (e.g., Spain, Portugal), after a noticeable recovery during the last few decades once the hunting ban was established. Only 6-10% of the world total is apparently still decreasing, mostly due to agricultural intensification, other causes of habitat degradation, and locally, also illegal hunting and collision with power lines. A small fraction of the world population (3-4%), is clearly (Germany, Austria) or apparently (Hungary) increasing, due to management and conservation measures. Finally, 19-22% of the world total has an uncertain status, due to inaccurate current or past censuses which prevent establishing reliable population trends. We recommend 1) keeping conservation efforts and the species' protection status worldwide, and 2) carrying out urgently nation-wide surveys in countries with low quality estimates, in order to confirm world numbers and trends.

15
Abstract:

With the knowledge that cuckoos and cowbirds lay their eggs parasitically, and that some hosts eject parasitic eggs, ornithologists began to ponder the question of how host females discriminate between a foreign egg and their own eggs, wondering how hosts "know" which egg to remove. Results of one of the first uncontrolled experiments were inappropriately interpreted to imply ejection was based on discordancy, with hosts simply ejecting the egg in the minority, or the "odd-looking" egg. Controlled experiments eventually revealed that hosts first learn the appearance of own their eggs and discriminate between them and any odd egg in their nest, regardless of which egg type is in the minority. Recent work has shown that discordancy may play a role in discrimination by males mated successively with females that lay polymorphic eggs. We examine the details of the early experiments, in light of recent advances in studies of egg recognition. An ability to recognize eggs also has been extended, implicitly, to include obligate brood parasites, as it underlies several hypotheses in explanation of the behavior of parasites toward their hosts. Egg recognition in parasites, however, has not been experimentally confirmed, nor has a mechanism been identified by which parasites could discriminate between their own eggs and the other eggs in a nest. We review hypotheses (parasite competition, egg removal and multiple parasitism, mafia, farming) that require the ability of obligate brood parasites to discriminate eggs at different levels and the potential mechanisms used by parasites to recognize their own eggs and suggest experiments to test for egg discrimination. An assessment of the egg recognition ability of parasites is germane to our understanding of how parasites counteract defenses of hosts.

16
Abstract:

Given the rapid rise in human population and increasing urbanization,it is important to understand their potential impacts on biodiversity. From March 2007 to August 2007, we conducted bird surveys in 90 strip transects,each 3 km long and 100 m wide,along a gradient of urbanization in Hangzhou,China. This gradient spanned a range of urbanization levels including urban areas,rural-urban continuum areas,farming areas,mixed forest/farming areas and forested areas. We recorded 96 breeding bird species and classified them into nine functional groups based on nesting requirements. The nine functional groups consisted of canopy nesters,shrub nesters,canopy/shrub nesters,natural cavity nesters,building nesters,natural cavity/building nesters,ground nesters,water surface nesters and parasitic nesters. Species and functional diversities were estimated based on the Shannon-Wiener index. Environmental data of each transect as human disturbance,vegetation cover and building index were also measured,and a synthetic urbanization index of each transect was introduced based on these data. We used regression analyses to model the relationship of species abundance,species diversity,functional abundance and functional diversity with this synthetic index. The results show that urbanization significantly reduces species richness,species diversity,functional richness and functional diversity,but the specific patterns differed. The relationship between species abundance/species diversity and urbanization is linear. In contrast,the relationship between functional diversity and urbanization was quadratic. In other words,with increased urbanization,functional diversity declined only slightly at first but then dropped at an accelerating rate. This implies that,although moderate urbanization reduces species diversity of breeding birds,it affects functional diversity of breeding birds only slightly in Hangzhou. The regression analysis of species diversity and functional diversity suggests a quadratic relationship between species diversity and functional diversity,i.e.,a linear relationship between species diversity and functional diversity can only exist at low diversity levels across urbanization gradients and increasing species abundance does not lead to an increase in functional diversity at the highest diversity levels.

17
Abstract:

The winter diet and morphological structure of the gastrointestinal tract of the Golden Pheasant (Chrysolophus pictus) was investigated in the Qinling Mountains, Shaanxi Province in 2002/2003. Individual food items in crops were identified by species, where possible, using standard taxonomic methods. The Golden Pheasant consumes exclusively vegetarian foods in the winter, of at least 14 plant species, such as crops and other vegetable species. The digestive tract of the Golden Pheasant is composed of an oesophagus, a stomach, a relatively long intestine measuring 3.4×standard body length, two fully-developed caeca and a relatively short colon, typical for herbivorous birds. Pebbles of different sizes (0.5-3 mm in diameter) were very frequent in the gizzard. The average dry weight of the pebbles was 10.4±2.5 g and was positively correlated with the weight of digesta in the gizzard (Pearson r=0.747, p < 0.01, n=37). The mucosa surface pH of the digestive tract of the Golden Pheasant was slightly acidic, but higher in the crop and gizzard.

18
Abstract:

The Sociable Lapwing (Vanellus gregarius) was recently categorized as Critically Endangered by the IUCN due to a strong decline and overall range contraction. Until now the only published Chinese record of the species was a vagrant sighting in 1998. We reviewed reports and historic literature from a German ornithological expedition in 1876, which reported the species to be a breeding bird in Xinjiang, western China in the second half of the 19th century. According to local expertise, the species seems since to have become extinct in Xinjiang, but surveys are suggested to clarify its current status.

19
Abstract:

Poyang Lake is a very important wintering place for cranes in China and East Asia. Two crane surveys were conducted at Poyang Lake during the 2011/2012 winter, the first on 18-19 December 2011 and the second on 18-19 February 2012. The survey covered the entire Poyang Lake basin, as well as two main lakes in Jiujiang (Saicheng Hu and Chi Hu), i.e., a total of 85 sub-lakes were surveyed. Both surveys recorded four species of cranes. The first survey on 18-19 December 2011 recorded 4577 Siberian Cranes (Grus leucogeranus), mostly in Bang Hu, Sha Hu and Dahu Chi, 302 Hooded Cranes (G. monacha), 885 White-naped Cranes (G. vipio) and 8408 Eurasian Cranes (G. grus), for the most part in the center of the lake basin. The second survey on 18-19 February 2012 recorded 3335 Siberian Cranes (mostly in Poyang Lake National Nature Reserve (PLNR) and its surrounding areas), 110 Hooded Cranes (largely in PLNR and its surrounding areas), 283 White-naped Cranes (86% in Bang Hu) and 2205 Eurasian Cranes (particularly in Duchang and Nanjishan NNR). The number of Siberian Cranes enumerated in December was 1000 more than the second count in February 2012. It is not possible to rule out double counting due to the close proximity of the main sites of the Siberian Cranes. During winters from 1998 to 2009, the average of the highest counts each winter was 3091, ranging from 2345 in 1996 to 4004 in 2002. By comparison with counts taken at other times, we therefore estimate a wintering population of Siberian Cranes of~3800-4000 at Poyang Lake. Additional evidence will be needed to raise the world population estimate. Our more recent surveys indicate a continuing decline in the number of White-naped Cranes and an increase in Eurasian Cranes.

20
Abstract:

The phylogeny of Paridae and allies has been studied intensively during past decades. However, the phylogenetic relationship among species tends to become increasingly controversial as different genetic markers emerge. In our study, the partial mitochondrial genes cytochrome b (cyt b) and cytochrome c oxidase subunit Ι (COI) were obtained from 15 species that included 10 tits, 4 long-tailed tits and a Chinese penduline tit. Analyses were conducted on the combined cyt b and COI sequences with maximum likelihood and Bayesian algorithms. Based on strong, congruent support among the different temporal partitions and models of sequence evolution, a highly resolved consensus of the relationships among Parids and their allies has been formed. The monophyly of Paridae and Remizidae is strongly supported. However, the monophyly of Paridae and Aegithalos is rejected. This agrees with previous studies using other molecular markers. Our results suggest the promotion of the subgenus Machlolophus from genus Parus to a separate genus. The phylogeny of Aegithalos is robust in the current study. However, by considering differences of both morphological and molecular characters within species, we conclude that more data are needed to define their phylogeny. Based on the patterns of taxonomic diversity and endemism, we suggest the southwestern mountain ranges of China might be the center of origin of the Aegithalos species. Divergence time estimates for the long-tailed tits range from the late Miocene to the Pleistocene (from 5.5 to 0.1 Mya) using a calibration of 2% divergence per million years. In a comparative sense, we found a congruent genetic differentiation among sympatric distribution taxa.

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