Silver spoon effects of hatching order in an asynchronous hatching bird

The silver spoon hypothesis proposes that individuals which develop under favourable conditions will gain fitness benefits throughout their lifetime. Hatching order may create a considerable size hierarchy within a brood and lead to earlier-hatched nestlings having a competitive advantage over their siblings, which has been illustrated in some studies. However, there have been few explorations into the effect on subsequent generations. Here, using a 15-year-long study, we investigated the long-term fitness consequence of hatching order in the endangered crested ibis, Nipponia nippon, a species with complete hatching asynchrony. In this study, we found strong support for silver spoon effects acting on hatching order. Compared to later-hatched nestlings, first-hatched nestlings begin reproduction at an earlier age, have higher adult survival rates, possess a longer breeding life span and achieve higher lifetime reproductive success. Interestingly, we found carry-over effects of hatching order into the next generation. Nestlings which hatched earlier and became breeders in turn also produced nestlings with larger tarsus and better body condition. Additionally, we found a positive correlation among life-history traits in crested ibis. Individuals which started reproduction at a younger age were shown to possess a longer breeding life span. And the annual brood size increased with an individual’s breeding life span. This suggests that the earlier-hatched nestlings are of better quality and the ‘silver spoon’ effects of hatching order cover all life-history stages and next generation effects

Foraging habitat selection of overwintering Black-necked Cranes in the farming area surrounding the Caohai Wetland, Guizhou Province, China

Abstract Background Understanding how overwintering birds choose foraging habitats is very important for conservation management. The overwintering Black-necked Crane (Grus nigricollis) feeds on crop remains in farmlands; thus, reasonable conservation management of this type of farmland that surrounds wetlands is critical for the overwintering populations of the Black-necked Crane; however, it is not clear how the Black-necked Crane chooses the foraging land in the farmland. Methods A thorough field positioning survey of all foraging sites in farmland areas around the Caohai Wetland and a sampling analysis of habitat selection by the Black-necked Crane were conducted during the winters from 2016‒2017 and 2017‒2018. Results Multiple factors contributed to the selection of foraging habitat in farmlands, i.e., food factors (crop remains and tillage methods) > human disturbance factors (distance to road and settlement) > topography factors (slope aspect), listed according to the strength of influence. Additionally, Black-necked Cranes tend to choose farmland sites where there was no machine tillage, the crop remains were > 500 g/m2, the distance to residences ranged from 100 to 500 m, the distance to roads ranged from 50 to 100 m, and the slopes exhibited western or eastern aspects. As the winters progressed, the volume of the edible crop remains declined, and the influences of the other main factors also changed, i.e., the factors of human disturbance (distance to road and settlement) became less important, while the effect of the food factor (crop remains) was strengthened. Thus, the foraging sites near the road became more important. Conclusion The farming area surrounding the Caohai Wetland is very important for the overwintering Black-necked Crane. Food factors and human disturbance factors are the main factors that influence the choice of feeding ground

Three-dimensional niche partitioning between two colonially nesting ardeid species in central China

Abstract Background Interspecific competition is known to be strongest between those species that are both closely related and sympatric. Egrets are colonially nesting wetland birds that often overlap and can therefore be expected to compete in roosting and nesting habitat as well as in diet. According to the niche partitioning hypothesis, it is to be expected that these similar species would show differentiation in at least one of the main niche dimensions to reduce competition. We tested niche partitioning between the colonially nesting Little Egret (Egretta garzetta) and Cattle Egret (Bubulcus ibis) in temporal, spatial and trophic dimensions. Methods Field study was conducted in three mixed egret colonies in Yangxian County, southwest Shaanxi Province, central China. For each nest colony we recorded its spatial location, the height of nesting trees and of nests, the height of roosting trees and of roosting individuals within the trees. We determined the first egg-laying and first hatching dates of the two species. Craw dissection of storm-killed egret nestlings was used to measure the diet. Six transects were surveyed to study foraging habitat selection. Results We found that hatching time of Little Egrets peaked earlier (by about 1 month) than that of Cattle Egrets. Cattle Egrets nested and roosted higher than Little Egrets. The foraging habitats used by Little Egrets were dominated by river banks (73.49%), followed by paddy fields (13.25%) and reservoirs (10.84%), whereas Cattle Egret foraging sites were characterized by grasslands (44.44%), paddy fields (33.33%) and river banks (22.22%). Little Egrets consumed more fishes (65.66%) and Odonata larvae (13.69%) than Cattle Egrets, while Cattle Egrets were found feeding mainly on Coleoptera (29.69%) and Orthoptera (23.29%). Little Egrets preyed on larger mean biomasses of food items than Cattle Egrets. Conclusions Our results confirm the niche partitioning hypothesis as a mechanism for coexistence among ecologically similar species. In two coexisting egret species, niche partitioning is multidimensional, such that the two coexistent species occupy differing ecological space based on all three temporal, spatial and trophic niche dimensions

Complete mitochondrial genome of Eurasian Hobby Falco subbuteo (Falconiformes:Falconidae) and phylogenetic analyses

The Eurasian Hobby Falco subbuteo is a Falco bird belonging to the group Falconiformes, and was listed in Appendices II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora and listed as a Class II protected species on China's List of Wildlife under Special State Protection. In this study, the complete mitogenome of F. subbuteo was determined. The mitochondrial DNA is packaged in a compact 17,678 based pair (bp) circular molecule with A + T content of 54.70%. It contains 37 typical mitochondrial genes, including 13 protein-coding genes, 2 rRNAs and 22 tRNAs, and 2 non-coding regions (D-Loop). We reconstructed a phylogenetic tree based on mitogenome sequences of 13 Falconidae species and one outgroup. Phylogenetic analysis indicated that F. subbuteo was a sister taxon to F. cuvierii with node support 100. The new mitogenome data would provide useful information for application in conservation genetics and further clarify the phylogenetic evolution of this species

CI.allnestSUB

Lifetime breeding performance and breeding life-span of crested ibi

CI.nest_eachyear_SUB

Breeding performance for each years of crested ibi

Complete mitochondrial DNA sequence of yellow-legged buttonquail (Turnix tanki)

The Yellow-legged Buttonquail Turnix tanki is a species of the genus Turnix, which belongs to the order Charadriiformes. It is distributed across almost all of China. The International Union for Conservation of Nature has assessed the bird’s conservation status as ‘Least Concern (LC).’ We sequenced the complete mitogenome of T. tanki and examined its phylogenetic relationship with other charadriiformes species. The mitochondrial DNA is packaged in a compact 17,620 base pair circular molecule with A + T content of 57.90%. It contains 37 typical mitochondrial genes, including 13 protein-coding genes, two rRNAs and 22 tRNAs, and two non-coding regions. We reconstructed a phylogenetic tree based on mitogenome sequences of five Turnicidae species and one outgroup. Phylogenetic analysis indicated that T. tanki is a sister to T. suscitator

CI_survival rate

Adult survival rate of crested ibi

Complete mitochondrial genome of oriental pratincole Glareola maldivarum (Charadriiformes: Glareolidae) and its phylogenetic relationship

Oriental Pratincole Glareola maldivarum is a widely distributed water bird species of the Charadriiformes group across Eurasia. In this study, we reveal the mitochondrial genome sequence of the Oriental Pratincole for the first time. The length of the mitochondrial genome is 18,422 bp and contains 2 ribosomal RNA genes, 13 protein coding genes, 22 transfer RNA genes, and 2 D-loop sequences. We further provide a phylogenetic tree showing relationships among Oriental Pratincole and other Charadriiformes species

Complete mitochondrial genome of Black Drongo Dicrurus macrocercus (Passeriformes: Dicruridae) and phylogenetic analyses

The Black Drongo Dicrurus macrocercus is a bird belonging to the group Passeriformes, distributed almost all over the country in China. The conservation status of this species is Least Concern (LC) in IUCN. In this study, the complete mitogenome of D. macrocercus was determined. The mitochondrial DNA is packaged in a compact 17,056 based pair (bp) circular molecule with A + T content of 57.04%. It contains 37 typical mitochondrial genes, including 13 protein-coding genes, 2 rRNAs and 22 tRNAs, and 1 non-coding regions. We reconstructed a phylogenetic tree based on mitogenome sequences of 15 Dicruridae species and one outgroup. In trees, D. macrocercus was clustered as an independent clade with high support value (100). The new mitogenome data would provide useful information for application in conservation genetics and further clarify the phylogenetic evolution of this species