Radar observations of the stoop of the Peregrine Falcon Falco peregrinus and the Goshawk Accipiter gentilis

Measurements in 10-s intervals by a tracking radar showed average speeds of about 25 ms^-1 for a Peregrine Falcon Falco peregrinus and a Goshawk Accipiter gentilis during four stoops lasting 40–110 s, with angles of dive between 13^o and 64^o, and involving height losses between 450 and 1080 m. Maximum speeds during 10-s intervals were between 31 and 39 ms^-1 in the Peregrine Falcon, and close to 30 ms^-1 in the Goshawk. The observed speeds are well below the maximum possible terminal speeds in steep or vertical dives according to theoretical estimation. By adopting a moderate stooping speed, raptors may gain in hunting precision.     

Morphological properties of the last primaries,the tail feathers,and the alulae of Accipiter nisus,Columba livia,Falco peregrinus,and Falco tinnunculus

We investigated the mechanical properties (Young's modulus, bending stiffness, barb separation forces) of the tenth primary of the wings, of the alulae and of the middle tail feathers of Falco peregrinus. For comparison, we also investigated the corresponding feathers in pigeons (Columba livia), kestrels (Falco tinnunculus), and sparrowhawks (Accipiter nisus). In all four species, the Young's moduli of the feathers ranged from 5.9 to 8.4 GPa. The feather shafts of F. peregrinus had the largest cross‐sections and the highest specific bending stiffness. When normalized with respect to body mass, the specific bending stiffness of primary number 10 was highest in F. tinnunculus, while that of the alula was highest in A. nisus. In comparison, the specific bending stiffness, measured at the base of the tail feathers and in dorso‐ventral bending direction, was much higher in F. peregrinus than in the other three species. This seems to correlate with the flight styles of the birds: F. tinnunculus hovers and its primaries might therefore withstand large mechanical forces. A. nisus has often to change its flight directions during hunting and perhaps needs its alulae for this maneuvers, and in F. peregrinus, the base of the tail feathers might need a high stiffness during breaking after diving. J. Morphol. 276:33–46, 2015. © 2014 Wiley Periodicals, Inc.     

Activities and toxicological significance of hepatic microsomal enzymes of the kestrel (Falco tinnunculus) and sparrowhawk (Accipiter nisus)

Activities of hepatic microsomal monooxygenase and epoxide hydrolase in sparrowhawks and kestrels were determined using organochlorine substrates. Monooxygenase activities were low in the kestrel and very low in the sparrowhawk compared to those in the male rat, down to environmentally realistic substrate concentrations. Epoxide hydrolase activities were very low in both species. These activities are discussed in relation to feeding ecology and susceptibility to organochlorine pollutants.     

The breeding status of Peregrine Falcons Falco peregrinus in the UK and Isle of Man in 2002

Capsule Numbers of breeding Peregrines are now higher than ever recorded and the recovery of the species within the UK has continued since 1991.

Aims To estimate the current Peregrine breeding population and its changes over time by recording breeding evidence and nesting range occupancy at known and potential Peregrine eyries.

Methods Attempts were made to check all potentially suitable Peregrine nesting locations for signs of Peregrine occupation. Causes of nest failure were documented where possible. Estimates of occupancy of nesting ranges that could not be visited were based on the proportion of ranges occupied from visited nesting ranges in the same region.

Results In 2002, 1530 Peregrine nesting ranges were estimated to be occupied, comprising 1456 pairs or single birds confirmed as in occupation, and 74 estimated extras (5% of total occupied nesting ranges) that were not visited. Including non‐breeding singletons holding nesting ranges, the UK and Isle of Man figure of ‘Ratcliffe pairs’ was 1437. This showed a 12% increase from 1991 and a 64% increase from the 1930s. However, there were geographical differences in change, with rapid expansion in the south of England tempered by declines in northern Scotland.

Conclusions The primary reasons for the population increase is primarily because of range expansion driven by a plentiful food supply and perhaps an increased tolerance of human disturbance. In areas where the species has declined, various factors (separately or in combination) including reduced food supply and persecution are likely to be involved.     

The breeding population of Peregrine Falcon Falco peregrinus in the United Kingdom,Isle of Man and Channel Islands in 2014

Capsule: Overall numbers of Peregrines are higher than previously recorded, due primarily to the growth of lowland populations, despite declines in many upland areas.

Aims: To estimate the breeding population of Peregrines, and changes in this population over time, as well as to relate variation in trends and observed breeding success to variation in region, breeding site type and other ecological influences.

Methods: Two types of survey methods were used. Site-based visits focussed on locations where Peregrines were known to have bred previously, while area-based searches aimed to find all Peregrines breeding in randomly chosen 5?km?×?5?km squares. Findings from each method were used to estimate population size in different parts of the survey area. Breeding outcome and site type were assessed for most of the pairs found during either survey.

Results: In 2014, the breeding population of Peregrines in the UK, Isle of Man and Channel Islands was estimated at 1769 pairs. This is 22% larger than the population estimate from the previous survey in 2002. Most of this increase is accounted for by increases in lowland England. Populations in some upland areas have declined.

Conclusions: The gap between the fortunes of lowland and upland Peregrines has continued to grow, along with the overall UK population. Likely reasons for the continued success of Peregrines in the lowlands include increasing uptake of breeding sites on human structures, abundant availability of prey in many lowland situations and, in many areas, a relative lack of conflict with humans. Factors likely to be limiting upland Peregrine populations vary between different regions, and include ongoing illegal killing and deliberate disturbance, and food supply.     

河南董寨赤腹鹰孵卵节律与巢防卫行为

2016和2017年的5月至8月,在河南省董寨国家级自然保护区利用红外相机监控和野外直接观察赤腹鹰(Accipiter soloensis),对其孵卵节律和巢防卫行为进行了研究。为了更好地获得巢防卫数据,我们以人作为入侵者攀爬巢树,观察人停留在巢树上10 min内不同赤腹鹰个体的巢防卫行为。共发现赤腹鹰繁殖巢52个,累计拍摄红外照片661 306张,将15个繁殖巢内的30只个体的巢防卫行为分成了4个等级。研究表明:1)雄鸟的巢防卫等级与雄鸟的日孵卵次数(r=0.751,n=15,P0.01)、雄鸟日孵卵时间(r=0.803,n=15,P0.01)、每日雌雄孵卵总时间(r=0.527,n=15,P0.05)均呈显著正相关,雌鸟的巢防卫等级与雄鸟的日孵卵次数(r=0.717,n=15,P0.01)、雄鸟的日孵卵时间(r=0.619,n=15,P0.05)呈显著正相关(Sperman rank correlation);2)雌鸟巢防卫强度与雄鸟巢防卫强度呈显著正相关(r=0.743,n=15,P0.01);3)亲鸟的平均离巢时间与雄鸟的日孵卵次数(r=﹣0.680,df=11,P0.05)、雄鸟的日孵卵时间(r=﹣0.640,df=11,P0.05)、雌鸟的孵卵次数(r=﹣0.558,df=11,P0.05)、每日雌雄孵卵总时间(r=﹣0.772,df=11,P0.01)均呈负相关。可见,赤腹鹰的巢防卫强度和孵卵投入密切相关,并且配偶间的巢防卫行为存在相似性,可能与配偶选择和学习行为有关。     

Spatio-temporal variation in post-recovery dynamics in a large Peregrine Falcon (Falco peregrinus) population in the Jura mountains 2000–2020†

After spectacular population crashes in the 1960 and 1970s, Peregrine Falcon Falco peregrinus populations recovered worldwide, and in the 2000s many study populations were back to normal. However, post-recovery trends have been documented less well. We combined three long-term population studies covering the entire Jura mountain range (16 304 km²) to examine spatio-temporal variation in population dynamics during 2000–2020 in 420 known nesting sites in five regions: Ain, Jura and Doubs in France, and Jura Sud and Jura Nord in Switzerland. Every year about 60% of all sites were surveyed at least once, and this proportion increased over time. We used Bayesian occupancy modelling to investigate site persistence and colonization probabilities and correct status and trend estimates for bias due to non-random site coverage. Based on the average of two models correcting for preferential sampling, we estimated that population size peaked in 2002 (Jura), 2005 (Doubs), 2007 (Ain, Jura Nord) and in 2007 for the Jura as a whole. Thereafter, the population declined significantly in four regions and in the Jura as a whole, with the strongest decline found in the Jura Nord ( –38%, 95% credible interval –34%/–41%) during 2007–2020. Thus, we found considerable spatial heterogeneity in post-recovery trends and widespread post-recovery declines. Reasons for the latter may include Eagle Owl Bubo bubo predation, illegal persecution and human disturbance. Our results illustrate how quickly positive population trends may be reversed, such that continuous long-term monitoring even for species seemingly ‘out of danger’ remains invaluable. Our study also emphasizes the importance of correcting for both coverage bias in general and preferential sampling in particular when assessing population trends in studies where not every territory can be surveyed in all years.     

Black-and-white plumage in male pied flycatchers (Ficedula hypoleuca) reduces the risk of predation from sparrowhawks (Accipiter nisus) during the breeding season

Bright colors in birds might signal that they are undesirableas prey (aposematic), an idea that has been difficult to test.When stuffed pied flycatchers Ficedula hypoleuca are exposedto migrating sparrowhawks Accipiter nisus in spring or in autumn,the hawks attack cryptic females more often than bright males.To achieve better statistical control and to assess whethermale plumage also reduces predation risk in the breeding seasonand in the nesting habitat of the pied flycatcher, I placedpairs of male and female flycatcher mounts in similar positionsnear 22 nests of sparrowhawks. The hawks attacked mainly femalemounts, verifying that the preference is real. The sparrowhawkscaught at least 19 live pied flycatchers; 12 young, 5 adultmales, 1 adult female, and 1 female or young. Hawks that caughtan adult male seemed to prefer attacking female mounts. I discussthree interpretations of these results, suggesting that black-and-whitemale flycatchers may benefit from being a novel and aberrantprey, at least early in the breeding season.     

Site fidelity and home range variation during the breeding season of peregrine falcons (Falco peregrinus) in Yamal,Russia

Many different ecological factors affecting the size, use, and spatial configuration of home ranges have been investigated, yet the chronology of the breeding cycle has been relatively under studied. Here, we studied peregrine falcons (Falco peregrinus) to describe variation in home range within and between breeding seasons in the Yamal peninsula, a region of the Russian Arctic with a high breeding density of peregrines. We used satellite telemetry to investigate variation in home range at different stages of the breeding cycle during three breeding seasons (2009–2011). We fitted Argos satellite transmitters to 10 breeding peregrines (nine females and one male) and two male fledglings. All breeding females showed fidelity to the region of the southwestern Yamal peninsula, but they were not necessarily faithful to their specific breeding ranges with 33 % dispersing to new ranges up to 40 km away. The population of peregrines in our study area was relatively synchronous in their breeding chronology, with clutches initiated in close synchrony in early June despite the birds arriving on their breeding ranges ca. 3 weeks earlier. The average home range size for breeding females was 98 km² (95 % Maximum Convex Polygon). Over the breeding season, the home range area utilized by females increased in the late nestling period and again after the chicks fledged. Expansion of the home range coincided with changes in behavior associated with parental care, resulting in greater activity and more time spent away from the nest area when the female began hunting to provision nestlings and fledglings.     

Changes in protein expression profiles in bivalve molluscs (Chamaelea gallina) exposed to four model environmental pollutants

Proteomics has been used in the clam Chamaelea gallina as a preliminary screening of changes in protein expression caused by pollutants, potentially useful as new biomarkers. Clams were exposed in water for seven days to four model contaminants, Aroclor 1254, copper(II), tributyltin (TBT), and arsenic(III), and cytosolic fractions were initially analyzed by two-dimensional (2-D) electrophoresis in 7 cm IPG strips (pH 4-7). On average, about 1000 spots were resolved and altered expression was qualitatively detected in 9-26 spots per treatment. Aroclor 1254, Cu(II) and As(III) had a mainly upregulating effect, in contrast to TBT. Altered protein expression was confirmed in 18 cm gels (at narrow pH ranges). The 15 spots more drastically altered were excised and analyzed by mass spectrometry (MS), and four proteins were identified. Aroclor 1254 and Cu(II) upregulated putative isoforms of tropomyosin and light chain of myosin. Actin was downregulated by Aroclor and Cu(II) but upregulated by TBT and As(III), while the opposite behavior was shown by a truncated actin form, homologous to the Drosophila act87E gene product. The exclusive identification of cytoskeletal proteins could reflect their relative abundance, their prevalence in databases in molluscs, or their role as major targets of pollutant-related oxidative stress.     

Changes in the content of glycogen and its metabolites during acute exposure ofAnabas testudineus (Bloch) to furadan

Significant differences were observed in glycogen metabolism ofAnabas testudineus exposed to an acute lethal (1.56 mg/litre) and a sublethal (0.56 mg/litre) concentration of furadan. At sublethal concentration, the muscle glycogen which was utilized during the early periods of exposure, was replenished in the later period of exposure and at 120 h, the muscle glycogen levels were higher than the control. At higher concentration, the liver glycogen levels showed an increase presumably at the expense of fuel reserves of the muscle.     

Changes in the amounts of amino acids associated with nerve endings (synaptosomes) during synaptogenesis

Changes in the amounts of proteins and amino acids in synaptosomes and whole tissue from the olfactory bulb and cerebral cortex of rats were measured during the period 5-25 days postnatal. The amount of neurotransmitter type amino acids (such as GABA, glutamate and aspartate) associated with synaptosomes obtained from 1g of brain tissue increased dramatically with the age of the animals, whereas non-transmitter type amino acids (such as serine and glutamine) showed relatively little change. The results were in harmony with an earlier cessation of synaptogenesis in the olfactory bulb than in the cerebral cortex.     

Identification of proteomic signatures of exposure to marine pollutants in mussels (Mytilus edulis)

Bivalves and especially mussels are very good indicators of marine and estuarine pollution, and so they have been widely used in biomonitoring programs all around the world. However, traditional single parameter biomarkers face the problem of high sensitivity to biotic and abiotic factors. In our study, digestive gland peroxisome-enriched fractions of Mytilus edulis (L., 1758) were analyzed by DIGE and MS. We identified several proteomic signatures associated with the exposure to several marine pollutants (diallyl phthalate, PBDE-47, and bisphenol-A). Animals collected from North Atlantic Sea were exposed to the contaminants independently under controlled laboratory conditions. One hundred and eleven spots showed a significant increase or decrease in protein abundance in the two-dimensional electrophoresis maps from the groups exposed to pollutants. We obtained a unique protein expression signature of exposure to each of those chemical compounds. Moreover a set of proteins composed a proteomic signature in common to the three independent exposures. It is remarkable that the principal component analysis of these spots showed a discernible separation between groups, and so did the hierarchical clustering into four classes. The 14 proteins identified by MS participate in alpha- and beta-oxidation pathways, xenobiotic and amino acid metabolism, cell signaling, oxyradical metabolism, peroxisomal assembly, respiration, and the cytoskeleton. Our results suggest that proteomic signatures could become a valuable tool to monitor the presence of pollutants in field experiments where a mixture of pollutants is often present. Further studies on the identified proteins could provide crucial information to understand possible mechanisms of toxicity of single xenobiotics or mixtures of them in marine ecosystems.     

Cytobiochemical characteristics of the function of pulmonary alveolar macrophages during development of immune reactions after exposure to chemical air pollutants

Based on an analysis of correlations between variation in the amount of alveolar macrophages of rat lungs and activity of enzymes localized in these cells (acid phosphatase, beta-galactosidase, beta-glucosidase, lactate dehydrogenase), the cytobiochemical changes in the function of pulmonary alveolar macrophages have been defined with the use of a model of permanent inhalation exposure to sulfur dioxide. The use of the model enables the dilimitation of the stages of defence-compensatory reactions and their transition to an unfavourable biological effect. The results obtained may serve as a theoretical basis for recommending a wider experimental application of the tests in question during regulation of environmental factors.