北京地区红隼的迁徙路线和活动区域

红隼（Falco tinnunculus）被列为国家二级重点保护野生动物,是能同时适应农村和城市环境的小型猛禽,对维持城市生态系统稳定具有重要意义。2022年4月至7月,为在北京救助的7只红隼佩戴了卫星追踪器,追踪其活动轨迹,依据追踪的动物活动位点数据,采用净平方位移-时间曲线依次对各红隼的迁徙模式进行了判别,深入分析了迁徙红隼的迁徙时间、距离和路线等,并采用核心密度法分别计算了迁徙及留居型红隼95%及50%活动区面积。研究结果表明,在北京地区红隼的迁徙模式为部分迁徙,追踪的7只红隼个体（N01～N07）中,4只为留鸟,1只为迁徙鸟,2只居留类型无法准确判断。N01为迁徙红隼,其度夏地和越冬地分别在内蒙古锡林郭勒盟和河北廊坊,此红隼秋季迁徙速度明显高于春季,其春季迁徙距离551 km,历时25 d,平均迁徙速度为22 km/d,而秋季迁徙距离412km,历时2 d,平均迁徙速度为203 km/d,河北承德滦平县是其春季迁徙的重要中途停歇地。不同红隼个体间95%及50%活动区面积均存在较大差异,迁徙红隼N01 95%、50%活动区面积在度夏区分别为93.10 km²、17.50 km²,在越冬区分别为7.03 km²、0.99 km²;留居型红隼95%、50%活动区面积均值分别为1 165.34 km²、178.71 km²（n=4）,其中最大95%、50%活动区面积分别为4 320.26 km²（N02）、648.22 km²（N02）,最小95%、50%活动区面积分别为2.80 km²（N03）、0.29 km²（N03）。本研究揭示了北京地区红隼的迁徙模式、迁徙路线、重要停歇地及活动区状况,为红隼的针对性保护和管理提供了科学依据。     

The predatory behaviour of common kestrels facing various types of prey

Nine rehabilitated adult common kestrels (Falco tinnunculus) were tested for predatory behaviour. Tests were carried out individually on four different prey: two invertebrates (grasshopper and earthworm) and two vertebrates (lizard and laboratory mouse). The birds were offered prey randomly once daily, not necessarily on subsequent days. The latency to attack was similar. In contrast to predation tests with vertebrates, kestrels preying on invertebrates landed mostly (P<0.01 for earthworm and P<0.05 for grasshopper) a few centimetres from the prey itself, grasping it after a few steps. Earthworms were gripped almost invariably with the beak, but other prey with the toes. The birds struck the prey with their beak at highly variable rates (P<0.001): vertebrates mostly with the beak, while earthworms were never struck. The latency to ingest prey varied greatly (P<0.001) between prey. Captivity had only limited importance; it did not affect the behaviour sequence on any prey, but just induced kestrels in captivity for long time to attack mice with shorter latency and to strike them more with the beak. It is then demonstrated that the common kestrel has a strong behavioural plasticity even within the predatory sequence, which is then not stereotyped, and is able to modify its behaviour patterns in relation to different prey.An erratum to this article can be found at     

Phenotypic, genetic, and environmental causes of variation in yellow skin pigmentation and serum carotenoids in Eurasian kestrel nestlings

In the context of sexual selection and parent-offspring communication, carotenoid-based coloration operates as a dynamic condition-dependent signal, as pigments stored in the skin and in the bill can be reallocated to other tissues in accordance with physiological needs. We studied the proximate factors affecting the carotenoid-dependent coloration of the Eurasian kestrel (Falco tinnunculus). Kestrel nestlings show carotenoid-based coloration at the integument level. Adult males and females share similar characteristics, but to a different extent. By cross-fostering nestlings, we evaluated the importance of the “nest of rearing” and the “nest of origin” to determine variation in skin color and blood carotenoids. The nest of rearing accounted for most of the observed variance in skin color, as well as serum carotenoids, while the nest of origin was not causal to the variability of carotenoids in young kestrels. The study indirectly shows that carotenoid-based color expressed by young kestrels is not affected by pre-laying conditions. Furthermore, we found that carotenoid coloration and blood carotenoid concentration were correlated at phenotypic and environmental levels, while the hereditary component of the carotenoid traits was too low to estimate their correlation at the genetic level.     

Does larder-hoarding affect the condition of chicks in urban kestrels?

Hoarding by urban kestrels and its subsequent exploitation significantly increases the frequency and regularity of feeding during the early stage of the nestling period. Twelve kestrels’ nests situated in various part of the city were chosen to test whether hoarding could affect the chicks’ condition. Four nests (with 22 nestlings) were provided with food — one dead mouse per chick per day (F group) and 8 (43 nestlings) were used as a control group (NF). Nestlings were weighed daily, and the length of their tarsus was also measured when the oldest chick in the nest was 11 days old. 50% of the NF nests experienced a decrease in the number of nestlings but no nestlings were lost in any of the F nests. However, no significant differences were found between the groups either in body mass or tarsus length. A possible reason was the behaviour of the adults which could be interpreted as the regulation of the frequency of prey delivery depending on its presence or absence in the nest.     

Sources of variation for nutritional condition indices of the plasma of migratory lesser kestrels in the breeding grounds

Although published information on reference values for biochemical parameters in birds of prey has increased during the last years, little is known on their sources of variation. We used an insectivorous and small migratory raptor species, the lesser kestrel Falco naumanni, as a model. We looked for sources of variation of nutritional biochemical parameters (i.e. triglycerides, cholesterol, uric acid and urea) of both nestlings and adults. Reference values indicated that, as a rule, lesser kestrel showed more elevated triglycerides, urea and uric acid levels than other raptors. All analyzed factors except gender (i.e. year, colony, sampling time, presence/absence of a geolocator, body mass, laying date and capture date) reached significance for at least one biochemical parameter. In the morning, we found an important postprandial increase in the concentration of all biochemical parameters in nestlings, and uric acid and urea levels in adults. A positive relationship was detected between triglycerides and body mass in nestlings and adults. Although we did not find differences between blood biochemical parameters of the oldest and youngest chick of each brood, we found that cholesterol levels were lower in nestlings from larger broods. Coloration of tarsi (measured as brightness) was related to triglycerides and urea levels of nestlings and adults, respectively. The feeding habits of lesser kestrel probably explain the different levels and patterns of variation of metabolites in comparison to more carnivorous raptors eating mammals or birds.     

Parental care behavior in the monogamous,sexually dimorphic Madagascar paradise flycatcher: sex differences and the effect of brood size

I studied the parental care behavior of the Madagascar paradise flycatcher Terpsiphone mutata in northwestern Madagascar. I especially focused on feeding, brooding and vigilance behaviors. Feeding rate did not differ between males and females, but females spent more time at the nest than males. Females dedicated their time to brooding, while males perched on the nest and were vigilant. Both parents changed the feeding rate in relation to brood size, so the feeding rate per nestling was not different among nests of different brood size. Duration of brooding by females increased with decreasing brood size, suggesting that the Royama effect, the pattern of lower feeding rate per nestling in larger broods, did not apply in this study. Males spent more time on vigilance than females. Anti-predator vigilance by males should be important for nestling survival given the high predation pressure typical of this population. In conclusion, males provide considerable parental care probably to minimize nestling starvation and to avoid nest predation. My results are not consistent with the general pattern of less parental effort by males in monogamous, sexually dimorphic species.     

红隼翼形态和附肢肌肉的反向性二态

反向性别二态性是进化生物学探讨的一个深刻问题,有助于理解物种的适应性和进化过程.猛禽是鸟类中为数不多的反向性别二态性的典型代表,但有关的定量研究并不多见,对体重的比较分析发现其反向性二态的程度与猎物类型有密切关系.表征猛禽飞行与抓捕能力的翼形态和附肢肌肉的性二态研究相对更少.本研究以9只雌性和3只雄性红隼(Falco tinnunculus)为研究对象,测量了6个翼形态参数,解剖分离了胸大肌和胸小肌,以及14块与抓握相关的后肢肌肉,并对各肌肉质量进行称量.对这些参数进行分析,以探讨翼和肌肉的反向性二态.结果发现,雌鸟的翼展、翼面积和翼负载均大于雄鸟,但雄鸟的翼端比雌鸟更尖.虽然这些差异无统计学意义,但在一定程度上也反映了雄鸟的飞行能耗低,利于其高效觅食,可为在巢雌鸟和雏鸟提供充足的食物.肌肉质量与功率输出成正比、决定了总的做功能力.雌性胸大肌质量显著高于雄鸟,14块后肢肌肉中仅有第二趾深及浅屈肌和第二趾收肌呈现了显著的反向性二态.腿肌的结果一方面反映了雌鸟与雄鸟抓握能力近似,另一方面也说明雌鸟第二趾在捕猎过程中具有力量优势,使其能捕猎体型稍大的猎物,比雄鸟有相对更大的猎物体型范围.综合前人的研究以及红隼的结果,推测翼形态和附肢肌肉的反向性二态及其程度与体型的反向性二态程度类似,均与食性存在密切关系.     

Parental condition affects early life-history of a coral reef fish

Parents can exert a range of non-genetic effects on the growth and survival of their offspring. In particular, parents may modify the size or condition of their offspring depending on the amount of energy they have available for reproduction. In this study, the body condition of breeding pairs of the coral reef fish Acanthochromis polyacanthus was experimentally manipulated to test the effects of parental condition on reproductive output and offspring life history traits. Parents in good condition commenced breeding earlier, had higher reproductive output, and their eggs exhibited increased survival during embryogenesis, compared to parents in poorer condition. Increased reproductive output was attained through more reproductive bouts over the breeding season that contained both a greater number and an increased size of eggs. The offspring from parents in good condition were larger at hatching, with larger yolk reserves and increased survival on endogenous reserves. Larger size is expected to provide benefits to offspring through reduced susceptibility to size-selective mortality. The range of offspring characteristics modified by parental condition could result in a greater proportion of offspring from good condition parents recruiting to the population.     

Parental care and infant development in a family group of captive Sichuan golden monkeys (Rhinopithecus roxellanae): First 20 days

A male Sichuan golden monkey (Rhinopithecus roxellanae) was born on July 24, 1986 to an adult pair on loan from the Chinese government. Physical and behavioral development of the infant, as well as the behavior of the parents, were recorded for the first 20 days of the infant's life. (On Day 21 the trio was returned to the Chongqing Zoo in the People's Republic of China.) The infant pelage was dark gray at birth but soon began changing to the orange-gold color typical of the adults. Forty hours of behavioral data were collected using a combination of scan sampling and all occurrences of selected behaviors techniques. The infant pushed against his mother and pulled toward objects in the enclosure beginning at 4 days of age. Time spent in these behaviors increased steadily and on Day 15 the infant broke contact with his mother for the first time. Mother-infant contact appeared to be maintained by both individuals mutually up to the infant's 10th day of the life. The percentage of time that the infant spent actively embracing his mother began to decline after that while the female continued to spend the majority of her time embracing the infant. During the first few days following the birth, the male always initiated and maintained proximity to the female and the infant. This “vigilant” behavior had declined somewhat by the end of the study.     

Are ecological compensation areas attractive hunting sites for common kestrels (Falco tinnunculus) and long-eared owls (Asio otus)?

Common kestrels (Falco tinnunculus) and long-eared owls (Asio otus) in intensively farmed areas in Switzerland decreased markedly as a result of declining vole (Microtus spp.) populations. In order to counteract the loss of biodiversity in intensively farmed areas, the Swiss agri-environment scheme stipulates several types of ecological compensation areas, which together should take up 7% of the farmland. Among them are wild flower and herbaceous strips, which are not mown every year and which in summer support up to 8 times more small mammals than ordinary fields and grassland. This study investigates whether kestrels and long-eared owls preferentially hunt on ecological compensation areas and whether preferred hunting areas are related to the density of small mammals or to the density and height of the vegetation. Both kestrels and long-eared owls mainly hunted on freshly mown low-intensity meadows and artificial grassland, despite low densities of small mammals. Therefore, vegetation structure was more important for the selection of hunting sites than prey abundance. However, both predators preferred to hunt on freshly mown grassland and meadows bordering a wild flower or herbaceous strip. Voles from these strips probably invaded the adjacent freshly mown grassland and became an easy prey for kestrels and owls. In intensively farmed regions, ecological compensation areas, particularly those not mown each year, are an important refuge for small mammals, although in summer the small mammals are not directly accessible to hunting birds. Hence, a mosaic of different habitat types with grassland mown at different times of the year together with undisturbed strips is best suited to provide a year-round supply of accessible food for vole hunters.     

Quantitative differences in sperm cells and organelles of tobacco (Nicotiana tabacum L.) grown under differing environmental conditions

In flowers grown at warm temperatures in environmental chambers and at cooler temperatures in the greenhouse, eight parameters of the sperm-cell organization of Nicotiana tabacum were examined during sperm cell maturation using serial ultrathin sectioning, transmission electron microscopy and quantitative cytology. Despite employing the same seed source, and similar soil and nutrient conditions, the surface area and volume of the cell, the nucleus and the chondriome were larger in flowers grown in growth chambers under warmer controlled conditions, whereas the number of plastids appeared to be the same, or slightly higher, in flowers grown under cooler greenhouse conditions. These results suggest that environmental conditions may influence the quantity of cytoplasmic organelles, including mitochondria and plastids, thus potentially influencing the likelihood of male cytoplasmic inheritance.     

Nest-building and communal care of young byTilapia rendalli dumeril (pisces,cichlidae) in Lake Malawi

Synopsis Tilapia rendalli of Lake Malawi dig large tunnels in their nests and practise communal care of young. Both these traits are considered to be antipredator adaptations.     

Correlates of oxidative stress in wild kestrel nestlings (Falco tinnunculus)

The fitness of an organism can be affected by conditions experienced during early development. In light of the impact that oxidative stress can have on the health and ageing of a bird species, this study evaluated factors accounting for the variation in oxidative stress levels in nestlings of the Eurasian kestrel (Falco tinnunculus) by measuring the serum concentration of reactive oxygen metabolites and the serum antioxidant barrier against hypochlorite-induced oxidation. The ratio between these two variables was considered as an index of oxidative stress, with higher values meaning higher oxidative damage. Six-chick broods showed the highest level of oxidative stress, while no effect of sex was found. Age showed an inverse relationship with the oxidants and the levels of oxidative stress, with younger birds having higher levels. Hatching date, body condition, body mass and carotenoid concentration did not show any relationship with oxidants, antioxidants or degree of oxidative stress. These findings suggest that intrabrood sibling competition could play a role in determining oxidative stress, and that in carnivorous birds other antioxidant molecules could be more important than carotenoids to reduce oxidative stress.     

Growth responses of fish to changing environmental conditions in a South Carolina cooling reservoir

Synopsis Significant changes in growth of bluegills,Lepomis macrochirus, largemouth bass,Micropterus salmoides, and black crappies,Pomoxis nigromaculatus, were observed in Keowee Reservoir, South Carolina, during the 10 years (1968–1977) following impoundment. During this period the reservoir filled, water temperatures were increased by heated effluent from a nuclear power plant, and threadfin shad,Dorosoma petenense, were stocked. Growth was apparently regulated by abundance and size of prey eaten by fish; elevated water temperatures had no measurable effect.     

Wheat anther culture: effect of genotype and environmental conditions

Twenty-two cultivars and lines of winter and spring wheat (Triticum aestivum L.) were studied, most for the first time, for their anther culture response. The response was genotype dependent. Plants grown in the field gave higher callus induction frequency than those grown in the greenhouse and the controlled environment chamber. Donor plants grown in a season of low drought stress as compared to a season of severe drought stress resulted in a higher frequency of callus induction. Spherical microcalli were observed in two wheat genotypes in some of only those anthers that were placed with only one loculus in contact with the medium. Wheat lines that were more responsive to anther culture were identified.     

Parental care in captive red-backed vole (Clethrionomys rutilus)

Parental behavior in ten pairs of male and female red-backed voles, Clethrionomus rutilus, was studied under laboratory conditions. Significant sex differences were found in total time spent in the nest, time spent by adults alone in the nest, grooming time, and nest-building activity; in half of the males under study, the level of paternal care was extremely low. These findings indicate different paternal contributions of female and male red-backed voles into the rearing of young, in agreement with the spatial-ethological structure of populations of this species. Parental behavior of C. rutilus is discussed in comparison with that of other species of the subfamily Microtinae.     

Photomorphogenesis inPhycomyces: Dependence on environmental conditions

The production of two kinds of vegetative reproductive structures, microphores and macrophores, byPhycomyces blakesleeanus Bgff. depends on plating density, ventilation, asparagine supply, and illumination. Quantitative determinations of these variables lead us to propose a new experimental system for developmental photobiology: standard plastic Petri plates containing 25 ml minimal medium are inoculated with 10⁵ viable, heat-activated spores and incubated, unpiled and unsealed, at 22° C. After 4 d microphores are counted and macrophores are weighed. Both microphorogenesis and macrophorogenesis are governed by light. Photosensitivity is a developmental phenomenon which occurs 32 to 68 h after inoculation, just before the beginning of vegetative reproduction in the dark controls. The maximum photosensitivity occurs 48 h after inoculation.     

Increased detrimental effects of ectoparasites on their bird hosts during adverse environmental conditions

Parasites are usually assumed to negatively affect fitness components of their hosts, particularly during adverse environmental conditions. We experimentally tested whether the ectoparasitic house martin bug (Oeciacus hirundinis) had larger negative effects on its house martin (Delichon urbica) host during second clutches. Conditions for reproduction decreased during the season, being less favourable for the second clutch than the first clutch. This was demonstrated by smaller clutch sizes, lower breeding success and smaller and lighter nestlings during the second clutch, as compared to the first, in the absence of parasites. Experimental manipulation of the intensity of parasitism resulted in the reproductive success of the host being reduced with increasing numbers of house martin bugs. This effect was much stronger during the second, as compared to the first, clutch. The house martin bug therefore had a greater detrimental effect on the reproduction of its host when conditions for reproduction were poor.