Aerial “flycatching”: non-predatory birds can catch small birds in flight

Aerial flycatching — the lightning-fast seizure of flying small birds in the beak of larger, not normally predatory birds, only a few cases of which are treated in the literature — is here described and discussed for white storks (Ciconia ciconia) and crows (Corvidae).Communicated by F. Bairlein     

绿鹭的繁殖习性观察

2001年4－9月在合肥市对绿鹭（Butorides striatus)的繁殖习性进行了观察。绿鹭营巢生境主要选择在建筑物附近的高大阔叶树上,常一树一巢,未见与其他鹭类混群营巢。每巢产3－5枚卵,孵卵期21d,育雏期41d,42日龄后幼鸟离巢飞走,出飞存活率62．5％。育雏期雏鸟主要食物为小型鱼类。在4所大学校园及1处公园统计到有效巢56个,推算绿鹭224只。绿鹭在合肥繁殖属首次记录。     

大豆属植物茎的次生木质部结构研究

利用光学显微技术和扫描电镜技术,对大豆属Clycine L.的4种类型植物茎材进行比较解剖学研究.结果表明,4种类型植物的茎材横切面均为散孔材。野生大豆茎材多为单管孔.少见复管孔;半野生大豆具复管孔,少见多细胞的管孔链;半栽培大豆茎材中复管孔和管孔链较多;而栽培大豆的复管孔和管孔链更多且普遍.野生大豆单列射线多,多列射线少半野生大豆有少数多列射线;半栽培大豆多列射线较多;栽培大豆多列射线细胞组成的射线最多.大豆种植物的次生木质部导管的侵填体分布不同,各种结构的演化途径为野生大豆→半野生大豆→半栽培大豆→栽培大豆野生大豆结构较原始,栽培大豆最进化.     

Integrating mark-recapture-recovery and census data to estimate animal abundance and demographic parameters

In studies of wild animals, one frequently encounters both census and mark-recapture-recovery data. We show how a state-space model for census data in combination with the usual multinomial-based models for ring-recovery data provide estimates of productivity not available from either type of data alone. The approach is illustrated on two British bird species. For the lapwing, we calibrate how its recent decline could be due to a decrease in productivity. For the heron, there is no evidence for a decline in productivity, and the combined analysis increases significantly the strength of logistic regressions of survival on winter severity.     

Feeding ecology of the waterbirds in a tropical mangrove in the southeast Gulf of Mexico

ABSTRACT

Species that exploit the same type of environmental resources are defined as a guild, which have similar needs in the use of food or habitat. It was analyzed the diet of five waterbirds’ offsprings species (Neotropic Cormorant (Nannopterum brasilianus), Reddish Egret (Egretta rufescens), Boat-billed Heron (Cochlearius cochlearius), Snowy Egret (Egretta thula) and Great Egret (Ardea alba)), by prey identification and calculated the relative importance, overlap and breadth diet. The general diet of the piscivorous guild consisted of 17 fish species from 13 genera and eight families. The highest overlap was between the Reddish Egret and Boat-billed Heron. Fish species dominated the diets of all studied waterbirds, Poecilia velifera was the most abundant prey species in each of the birds, suggesting that they are abundant in the wetlands system of northern Yucatan. Diet overlap in waterbirds species depends on the use of resources and feeding habitat. Since reproductive success largely depends on the availability of food resources, mainly of resident or estuarine fishes. The information about diet is important for the conservation of waterbirds.