Milvus Migrans Research Articles

Foraging strategies of black kites (Milvus migrans govinda) in urban garbage dumps

Large numbers of black kites (Milvus migrans govinda) forage with house crows (Corvus splendens) at garbage dumps in many Indian cities. Such aggregation of many individuals results in aggressiveness where adoption of a suitable behavioral approach is crucial. We studied foraging behavior of black kites in dumping sites adjoining two major corporation markets of Kolkata, India. Black kites used four different foraging tactics which varied and significantly influenced foraging attempts and their success rates. Kleptoparasitism was significantly higher than autonomous foraging events; interspecific kleptoparasitism was highest in occurrence with a low success rate, while ‘autonomous-ground’ was least adopted but had the highest success rate.

Variable Shifts in the Autumn Migration Phenology of Soaring Birds in Southern Spain

While alteration of the migratory habits of birds is widely regarded as one of the most evident ecological effects of climate change, studies reporting shifts in migration phenology for long-lived, long-distance migrants have been few. Using time series of count data collected in southern Spain during autumn migration, we examined the magnitude and direction of phenological shifts for six common species of soaring birds. Many current methods for investigating phenological change rely on continuous data sets; however, these data may be unavailable for a variety of reasons. We used a cross-correlation analysis, which allowed us to compare recent data on the timing of migration from 1999–2011 to a historic data set collected during 1976–1977. The direction of phenological shifts for autumn migration was species-specific. White Storks Ciconia ciconia and Black Kites Milvus migrans appeared to have delayed passage, Black Storks Ciconia nigra and European Honey Buzzards Pernis apivorus have advanced their migra...

Larval infestation in a common Pariah Kite Milvus migrans (Boddaert).

This paper describes a case of larval infestation in a common Pariah Kite Milvus migrans (Boddaert). Examination on the larvae revealed that the larvae were of the family Sarcophagidae (Diptera).

Genetic Diversity and Antibiotic Resistance Among Coagulase-Negative Staphylococci Recovered from Birds of Prey in Portugal.

Wild animal populations in contact with antimicrobials and antimicrobial resistant bacteria that are daily released into the environment are able to become unintentional hosts of these resistant microorganisms. To clarify this issue, our study evaluated the presence of antibiotic resistance determinants on coagulase-negative staphylococci recovered from birds of prey and studied their genetic relatedness by pulsed-field gel electrophoresis (PFGE). The unusual vga(A) and erm(T) genes, which confer resistance to clindamycin and erythromycin, respectively, were detected in Staphylococcus sciuri or Staphylococcus xylosus strains and the tet(K) gene in Staphylococcus kloosii. The PFGE patterns showed that three S. xylosus (isolated of Strix aluco and Otus scops) and two S. sciuri (recovered from Strix aluco and Milvus migrans) were clonally indistinguishable. These animals could be a source of unusual antimicrobial resistance determinants for highly used antibiotics in veterinary clinical practice.

Biomonitoring of metals and metalloids with raptors from Portugal and Spain: a review

The analysis of metals in different tissues of raptors has been an important tool for assessing metal pollution. Several studies using a range of sentinel raptor species have been carried out in Portugal and Spain since the 1980s to identify the adverse effects in the animals themselves and on their populations, to identify the contamination of the food chain, to determine the levels of environmental contamination and to estimate human health risks. The aim of this work is to provide synthesized information of the studies carried out in Portugal and Spain in the direct biomonitoring of metals and metalloids using raptors, through a systematic search of the published literature. The information is summarized taking into account specific issues, such as monitored raptor species, sampling periods, monitored areas, type of samples, analytical techniques used in the determination of the metals and metalloids, the analysed metals and metalloids, and overall analysis of the concentrations obtained. There is a striking difference between the number of studies performed in Portugal and Spain, and most of them have been carried out in Spain. The eagle owl, black kite, and common buzzard were the species from which the greatest number of individuals have been analysed. Among the most analyzed biological samples, the blood and liver samples were used to measure the concentrations of all studied metals, while bone was mainly collected to evaluate chronic exposure to lead and feathers to evaluate exposure to mercury during feather growth. Atomic absorption spectrometry has been the most frequently performed technique to determine the majority of metals and arsenic. In general, the concentrations of metals detected in raptor samples from Portugal and Spain are low and insufficient to produce toxic side effects. Only lead, in certain cases, can be related with toxic side effects. However, particular attention should be given to mercury due to its high toxicity, its transport from an aquatic environment to the adjacent terrestrial food web, and because the mercury toxicity threshold has yet to be established for raptors. This work confirms the need for further biomonitoring studies of metals with raptors, especially in Portugal; the establishing of national programs to conduct long-term studies; and creating a network between Portugal and Spain to study environmental contamination using raptors.

Effects of Ontogeny, Diel Rhythms, and Environmental Variation on the Adrenocortical Physiology of Semialtricial Black Kites (Milvus migrans)

We examined whether hypothalamic-pituitary-adrenal axis activity in the nestlings of a semialtricial raptor, the black kite (Milvus migrans), varied with advancing age, throughout the day, and in response to a number of socioecological factors presumed to affect allostatic load. Both baseline corticosterone (CORT) titers and maximum CORT levels during 30 min of handling and restraint augmented across all sampled ages, suggesting that nestlings' energetic demands and capacity to respond to perturbations increase progressively throughout development. CORT secretion also peaked in the early morning, reached minimum levels in the central hours of the day, and increased again before dusk, suggesting a possible role of CORT in the regulation of activity-inactivity patterns. Finally, nestlings raised in a year of low marsh inundation, implying lower food availability and heightened allostatic loads, exhibited higher adrenocortical responsiveness to stress than nestlings raised in years of intermediate or high flooding. The nondetectable effect of other socioecological variables, such as territory quality, temperature, or brood order, suggests that parents may be able to buffer their nestlings from adverse environmental conditions or that the effect of such factors may have been obscured by selective mortality operating before sampling. We propose that future studies increase the simultaneous use of complementary techniques (fecal sampling, feather analysis) to reach firmer and more comprehensive conclusions, especially for planning the management and conservation of sensitive species.

Trends of autumn counts at Iberian migration bottlenecks as a tool for monitoring continental populations of soaring birds in Europe

Migration monitoring may allow us to detect population trends over large geographic areas because the pattern of change in migrant counts may be expected to follow the pattern of change in population size. We analysed recent regional European population trends of migratory soaring birds from rates of change in migration counts over the Strait of Gibraltar (Spain) during the years (1999–2013). An additional bottleneck (Organbidexka, France) within the same migratory route and period was also considered. We estimated count trends by fitting a log-generalized linear model to the time series of each species counts. The counts in Organbidexka were used to test the consistency in the observed trends over the Strait of Gibraltar. Migration counts of White and Black Storks, Black Kites, Short-toed and Booted Eagles as well as Egyptian Vultures showed a linear increase over the Strait of Gibraltar throughout the 15-year period. In contrast, Honey Buzzard numbers remained stable. Trends were highly consistent with those recorded in Organbidexka. We suggest that the larger slopes for the trends in Organbidexka when compared with the Strait reflect an increasing tendency in these species to overwinter in southern Europe. A combination of complementary data sets collected at different bottleneck sites within the European–African flyway system may become a fundamental tool for the investigation of migratory patterns and population trends and changes of soaring migrant birds all over Europe.

Nests of Black Kite (Milvus migrans govinda) in Urban Landscape of Kolkata, India

All birds construct nests to lay eggs and/or to raise offspring. Scientific description on the nest materials of Black Kite Milvus migrans govinda is very few and is particularly lacking in urban landscape. Therefore, the present study was carried out on three nests of Black Kites collected from different regions of Kolkata metropolis, India to generate quantitative data on the nest parameters and materials used by the Black Kites to construct nest in this urban metropolis of the country. All these nests of Black Kites were large oval shaped platform nests, which mostly comprised of dry twigs of various plants (1.265 ± 0.094 kg, range 1.147–1.452, n = 3), followed by fair amount of human derived (artificial) objects (0.507 ± 0.049 kg, range 0.42–0.59, n = 3) and clay (0.347 ± 0.038 kg, range 0.29–0.42 kg, n = 3). Dimensions of three nests did not vary significantly (Kruskal–Wallis test: H = 0.195, df = 2, P > 0.05), but the weight of ‘plant materials’, ‘human derived materials’ and ‘clay’ present in all three nests varied significantly (Kruskal–Wallis test: H = 6.88, df = 2, P < 0.05). Present study thus adds to the existing knowledge of nest materials used by Milvus migrans govinda and is the first scientific report on nest materials used by these diurnal raptors in Kolkata metropolis.

Temporal and spatial assemblages of invasive birds occupying the urban landscape and its gradient in a southern city of India

Common birds play an important role in regulating the functioning of urban ecosystems. Typically, a few common species have become invasive species threatening biodiversity worldwide. Our understanding of the dynamics of invasive birds in an Indian context is still in its infancy. Hence, we studied the gradual adaptation of invasive birds to novel habitats and their dispersal dynamics in a southern city of India. We tested the prediction that urban matrix are increasingly composed of invasive generalist species. The results illustrate the dominance of invasive species such as Corvus splendens, Acridotheres tristis, Acridotheres livia, and Milvus migrans in the urban environment. The significant abundance of C. splendens exhibited urbanization-induced homogenization. The land-use pattern showed more inclination toward the urban structures than the vegetative attributes. Specialist groups from the frugivore guild were found to decline from the urban environment, which may shed light on the ecological factors that constrain their distribution.

Visual abilities in two raptors with different ecology.

Differences in visual capabilities are known to reflect differences in foraging behaviour even among closely related species. Among birds, the foraging of diurnal raptors is assumed to be guided mainly by vision but their foraging tactics include both scavenging upon immobile prey and the aerial pursuit of highly mobile prey. We studied how visual capabilities differ between two diurnal raptor species of similar size: Harris's hawks, Parabuteo unicinctus, which take mobile prey, and black kites, Milvus migrans, which are primarily carrion eaters. We measured visual acuity, foveal characteristics and visual fields in both species. Visual acuity was determined using a behavioural training technique; foveal characteristics were determined using ultra-high resolution spectral-domain optical coherence tomography (OCT); and visual field parameters were determined using an ophthalmoscopic reflex technique. We found that these two raptors differ in their visual capacities. Harris's hawks have a visual acuity slightly higher than that of black kites. Among the five Harris's hawks tested, individuals with higher estimated visual acuity made more horizontal head movements before making a decision. This may reflect an increase in the use of monocular vision. Harris's hawks have two foveas (one central and one temporal), while black kites have only one central fovea and a temporal area. Black kites have a wider visual field than Harris's hawks. This may facilitate the detection of conspecifics when they are scavenging. These differences in the visual capabilities of these two raptors may reflect differences in the perceptual demands of their foraging behaviours.

Collaborating with Nature: The Pristine Habitats, in Ugep, Yakurr L.G.A., Nigeria

Pristine habitats serve as ecological resource for educational services and the conservation of biodiversity. The need to maintain a balance between nature and development is very important. When pristine habitats face changes due to anthropogenic activities, species erosion sets in and this will eventually lead to extinction. This subtle move in most cases is unnoticed until the effects are established. The pristine habitats in Ugep are faced with this challenge. The Ugep Urban Landuse Master Plan and Ugep Orthophoto map [1] have been used to identify the pristine habitats and further calculate the total landmass to be approximately 855.38 hectares. Ten (10) pristine habitats were identified within the residential blocks along the drainage corridors of Loblo, Isayi, Mma Oden, Kiwei, Ewiden and Oganghwen. The pristine block at Njelokoko-2 has the highest landmass, 201.01 hectares, representing 23.50 percent while Njelokoko-1 has the least landmass, 18.99 (2.22 percent). The spatial turnover of the species composition shows a trend of direct proportion with the landmass size and anthropogenic activities in the pristine habitats. Tree species such as Albizia zygia and Artocarpus communis rarely occurred together with other tree species. Among the bird species, it was observed that Dendropes goerae, Milvus migrans, Pica pica, and Streptopelia senegalensis roost, breed and feed in pristine habitats with emergent trees while Halocyno leucoephala, Halocyno malimbicus, Frasena clnernscens, Streptopelia semitorguata and Crimifer piscator are restricted to narrow corridors of pristine habitats along stream buffers. The nature that the pristine habitat portends and the species observed in such highly urbanized context as Ugep, are very important in conservation planning and meeting the urban challenges.

Predation Capability of Black Kite (&amp;lt;i&amp;gt;Milvus migrans parasitus&amp;lt;/i&amp;gt;) on Locust as a Biological Control Option in Madagascar

In Madagascar, the South and Southwest regions have for decades had locust outbreaks that have devastated crop fields. The locust species dominant in this area are the red locust (Nomadacris septemfasciata) and the Migratory Locust (Locusta migratoria capito). This paper aimed at determining the predation values from the Black Kite (Milvus migrans parasitus), a natural enemy for locusts, as a biological measure for locust outbreak control. Two types of experiments were done that included observed predation and experimental predation. It was observed, in the observed predation, that a higher number of locusts were found in the bird’s stomach during the afternoon session (mean = 66) than during the morning session (mean = 21). The high peak observed during the afternoon session was also associated with the feeding of larvae of the migratory locust. The experimental predation results showed that almost 100 percent of the larval and 97 percent of the fledglings were fed on. The experimental predation results also showed that there was no preference for larvae or fledglings in the cage and that the bird fed on the different combinations equally. This study showed that the Black Kite birds can effectively control locust population in an outbreak when they are easy to predate on. However, there is a need to assess the population of birds in locust infested areas to determine if the bird population is enough to predate on a locust outbreak.

Гнездовые предпочтения чёрного коршуна в лесополосах Алтайского края, Россия

This article describes the data on breeding ecology of the Black Kite breeding in shelter belts in south-eastern part of Altai Region. The length of the shelter belts studied in this work was 50 km. Through the period of this study a 72 nests of this species were revealed. We studied nesting preferences of Black Kites towards different wood species, ontogenetic state of trees, trunk diameter and tree strength using Ivlev-Jacobs electivity index. As a result we establish that the most preferable wood species is poplar ( Populus sp.) (electivity index is 0.5), birch ( Betula sp.) is used proportioned to its abundance (-0.02), and pine ( Pinus silvestris ) and maple ( Acer sp.) are mostly ignored. Kites also prefer middle-aged generative trees (0.74) and avoid old ones (-0,18). Trees with trunk diameter 31–40 cm considered as most preferable (0,23). And trees with trunk diameter 21–30 cm is used proportioned to its abundance (-0,04). Trees with another trunk diameter are mostly ignored or completely avoided. Based on the index of tree strength (ITS) we established that Kites breeding in the shelter belts prefer trees with ITS = 1.6–2.0 (0.31), trees with ITT = 1.1–1.5 and ITT = 2.1–2.5 are used proportioned to its abundance (-0.02 and -0.07, respectively), and trees with ITT above 2.6 or below 1 are ignored.

Ambient temperature, body condition and sibling rivalry explain feather corticosterone levels in developing black kites

Summary In birds, the steroid hormone corticosterone (CORT) is considered a major mediator in a number of physiological mechanisms and behaviours critical for the regulation of an organism's energy balance. However, the question of whether the way in which circulating plasma CORT is incorporated into feathers actually reflects this regulation, and consequently whether feather CORT (CORT‐F) measures allow to make inferences on past levels of energetic demands (also known as the allostatic load), remains unclear. While previous studies have yielded promising results, the technique still wants further study and validation in a wider range of bird species, across life‐history stages and under different ecological situations. Here, we tested whether CORT‐F levels in a sample of 427 nestling black kites (Milvus migrans) reflected interindividual variation in a number of environmental, social and physiological variables known to elevate allostatic load during development. We found that nestlings exposed to low ambient temperatures exhibited high CORT‐F, suggesting that feathers registered the expected rise in circulating CORT levels inducing thermogenesis in response to cold stress. CORT‐F was also negatively related to body condition, supporting the notion that allostasis becomes less affordable as energy stores become depleted. Finally, CORT‐F also reflected brood hierarchy rank, with subordinate chicks exhibiting the highest levels, followed by first‐hatched (dominant) chicks and lastly singleton nestlings. Moreover, CORT‐F levels in nestlings from multiple‐chick broods (but not in singletons) declined with age, mirroring the dynamics of establishment and stabilization of sibling hierarchies in black kites. Altogether, our results underscore the potential of using CORT‐F to infer allostatic load in wild avian populations and their potential power as indicator tools in conservation biology.

A rapid assessment of species-specific bird strike risk at the Kotoka International Airport in Accra, Ghana

The Kotoka International Airport in Accra, the capital city of Ghana, has in recent years been confronted with increased presence of birds posing great challenges to aviation safety due to a high risk of bird strikes. As part of measures to mitigate the negative impacts of increasing numbers of birds, a species-specific bird strike risk index (SSBR) was modelled and calculated for a total of 86 species recorded within and near the airport. Based on the SSBR index, four species were classified as ‘critical risk’ and another four species as ‘high risk’. All six species, namely Corvus albus, Necrosyrtes monachus, Milvus migrans parasitus, Bubulcus ibis, Falco biarmicus and Falco tinnunculus, constituting 7% of the total species assemblage, were considered ‘problem species’. During the intensive, albeit short, study period, we also recorded bird strikes of N. monachus, F. biarmicus and notably M. m. parasitus. We conclude that wildlife management to avert the risk of bird strikes could be successfully achieved by adopting both proactive and reactive measures to reduce the presence of problem species at the aerodrome.

A CFD Study on Leading Edge Wing Surface Modification of a Low Aspect Ratio Flying Wing to Improve Lift Performance

Low Aspect Ratio (LAR, aspect ratio &lt; 2) wings exhibit highly nonlinear lift curves. Controlling such LAR Mini Aerial Vehicles (MAVs) at high Angle of Attacks (AOA) and in cross-wind conditions is difficult due to the nonlinear lift. Also, maneuvering these MAVs at high AOA is highly constrained by elevator throw. However, high AOA is a requisite for MAVs to enable slow flight in constrained spaces. Conventional aircraft use devices called vortex generators (or turbulators) that delay the separation of boundary layer by artificially inducing vortices. A similar phenomenon is observed in golf balls, where the surface dimples mimic the above effect. It is also observed that the local vortices aid in additional lift generation. This paper presents a Computational Fluid Dynamics (CFD) study on the effect of dimples over the aerodynamic performance of a LAR flying wing with aspect ratio 1.45 &amp; SELIG4083 cross section. A Modified Inverse Zimmerman planform wing has been considered similar to the MAV (Black Kite) developed by the National Aerospace Laboratories Bangalore (NAL). The 3D model was generated in SolidWorks™ and CFD analysis was performed in SolidWorksTM Flow Simulation. The baseline smooth surface wing was validated with the aerodynamic data of SELIG4083 airfoil from literature. Following it, several dimpled wing configurations on the leading edge were created and analyzed. It was observed that dimples create local vortices that aid in lift generation, increasing the effective flight envelope. The associated drag due to local vortices should be overcome by generating additional thrust at high AOA.

No effect of satellite tagging on survival, recruitment, longevity, productivity and social dominance of a raptor, and the provisioning and condition of its offspring

Summary The deployment of electronic devices on animals is rapidly expanding and producing leapfrog advances in ecological knowledge. Even though their effects on the ecology and behaviour of the marked subjects are potentially important, &lt;10% of the studies are accompanied by an evaluation of impact, and comprehensive, long‐term assessments have been few. Therefore, there is an urgent need to test for impacts, especially for tags that are heavy and deployed for long time periods, such as satellite transmitters. We marked 110 individuals of a medium‐sized, migratory raptor, the black kite Milvus migrans, with GPS satellite tags, representing about 4% of the body mass and attached as backpacks through a Teflon harness. Tagged individuals were compared to control animals of similar sex, age and breeding status for a large number of behavioural, condition‐related and ecological traits. Despite a sample size two‐ to threefold greater than most previous assessments that reported significant impacts, there was no detectable difference between tagged and control individuals in key vital rates such as survival probability, longevity, recruitment, age of first breeding, reproductive performance and timing of breeding. Tagged and untagged kites showed similar social dominance during fights over food and a similar capability to provision nestlings, which prevented carry‐over effects on the stress levels and condition of their offspring. Synthesis and applications. Radio‐marking studies are growing exponentially in the current ‘movement ecology era’, and impact assessments will be ever more important. In principle, tags of up to 4% mass‐load can be deployed without apparent harm on some avian soaring species, but impacts should be properly evaluated on a case‐by‐case basis. Resilient species for which impacts seem weak could be used as early warning systems for trials of new devices: if impacts are observed, they are likely to be even greater on more vulnerable species. Finally, individual fatalities caused by marking should be taken into serious account, but comprehensively evaluated in the light of broader population‐level impacts. Future initiatives to minimize tagging impacts could include more stringent licensing criteria enforcing attendance at training courses or incorporation of impact evaluations into study designs, increased availability of training courses for tagging, and enhanced sharing of information through blogs, workshops or specialized journal sections.

Trade of threatened vultures and other raptors for fetish and bushmeat in West and Central Africa

AbstractDiurnal raptors have declined significantly in western Africa since the 1960s. To evaluate the impact of traditional medicine and bushmeat trade on raptors, we examined carcasses offered at markets at 67 sites (1–80 stands per site) in 12 countries in western Africa during 1990–2013. Black kite Milvus migrans and hooded vulture Necrosyrtes monachus together accounted for 41% of 2,646 carcasses comprising 52 species. Twenty-seven percent of carcasses were of species categorized as Near Threatened, Vulnerable or Endangered on the IUCN Red List. Common species were traded more frequently than rarer species, as were species with frequent scavenging behaviour (vs non-scavenging), generalist or savannah habitat use (vs forest), and an Afrotropical (vs Palearctic) breeding range. Large Afrotropical vultures were recorded in the highest absolute and relative numbers in Nigeria, whereas in Central Africa, palm-nut vultures Gypohierax angolensis were the most abundant vulture species. Estimates based on data extrapolation indicated that within West Africa 73% of carcasses were traded in Nigeria, 21% in Benin and 5% elsewhere. Offtake per annum in West Africa was estimated to be 975–1,462 hooded vultures, 356–534 palm-nut vultures, 188–282 Rüppell's griffons Gyps rueppellii, 154–231 African white-backed vultures Gyps africanus, 143–214 lappet-faced vultures Torgos tracheliotos, and 40–60 crowned eagles Stephanoaetus coronatus. This represents a sizeable proportion of regional populations, suggesting that trade is likely to be contributing significantly to declines. Stronger commitment is needed, especially by governments in Nigeria and Benin, to halt the trade in threatened raptors and prevent their extirpation.

IncA/C Plasmid Carrying bla(NDM-1), bla(CMY-16), and fosA3 in a Salmonella enterica Serovar Corvallis Strain Isolated from a Migratory Wild Bird in Germany.

A Salmonella enterica serovar Corvallis strain was isolated from a wild bird in Germany. This strain carried the IncA/C2 pRH-1238 plasmid. Complete sequencing of the plasmid was performed, identifying the blaNDM-1, blaCMY-16, fosA3, sul1, sul2, strA, strB, aac(6')-Ib, aadA5, aphA6, tetA(A), mphA, floR, dfrA7, and merA genes, which confer clinically relevant resistance to most of the antimicrobial classes, including β-lactams with carbapenems, fosfomycin, aminoglycosides, co-trimoxazole, tetracyclines, and macrolides. The strain likely originated from the Asiatic region and was transferred to Germany through the Milvus migrans migratory route.

Temporal trends in classical and alternative flame retardants in bird eggs from Doñana Natural Space and surrounding areas (south-western Spain) between 1999 and 2013

Several halogenated flame retardants were detected in black kite, white stork and greater flamingo unborn eggs from Doñana Natural Space (Spain) collected in 1999, 2003, 2011 and 2013. The main components of Penta-BDE commercial mixture (BDE-47, -99 and -100) showed a decrease in the studied time interval, concurring with the ban of this mixture in the European Union (EU) in 2006. On the other hand, BDE-209, the main component of Deca-BDE mixture showed a clear trend in black kites but further monitoring is needed since its production ceased at the end of 2013. Besides, even if Dechlorane Plus (DP) was proposed by the EU as an alternative to BDE-209 no time trends were observed. Furthermore, total concentrations of PBDEs (classical FRs) are still higher than concentrations of hexabromocyclododecane (HBCD) and alternative FRs halogenated norbornenes (HNs), which are theoretically substitutes of the already banned PBDEs.