1,723,359 research outputs found
Intermittent Gliding in the Hunting Flight of the Kestrel, Falco tinnunculus L.
Full text linkThe hunting flight of the kestrel (Falco tinnunculus) consists of short bouts of flight at wind speed against the wind with the eyes in a fixed position relative to the ground, and of short flights from one such position to the next.
High speed films taken with a camera in a fixed position of a hunting kestrel of known weight and dimensions, allow estimates to be made of the amount of energy required for this behaviour.
A theoretical model shows how a bird could economise by alternating flapping flight with short gliding bouts, without changing the position of the eyes above the ground, by mere displacement of the centre of gravity relative to the head. High speed film data confirm predictions from this model.
Evaluating the demographic history of the Seychelles kestrel (Falco araea): genetic evidence for recovery from a population bottleneck following minimal conservation management.
Full text linkAn important requirement for biologists conserving vulnerable species of wildlife and managing genetic
problems associated with small population size is to evaluate existing evidence regarding what is known
of a species’ recent population history. For endemic island species in particular, current genetic impoverishment
could be due to either a recent population crash or a consequence of an evolutionary history
of sustained isolation and small effective population size. Interpreting any given case can often be further
complicated by incomplete or contradictory evidence from historical field surveys that might suggest a
very different demographic history. Here, we use the case of the Seychelles kestrel (Falco araea), an island
endemic previously listed as critically-endangered but now relatively common, to illustrate how genetic
data from microsatellite genotypes of 100–150-year-old museum specimens reveals a recent and severe
population crash since the 1940s to approximately eight individuals, before the population recovered. We
re-interpret the historical population trajectory of the Seychelles kestrel in the light of the minimal intervention
required for this species to recover. We examine different ecological explanations for the decline
and apparently unassisted recovery of the Seychelles kestrel, review the evidence for similarly unaided
recoveries elsewhere and discuss the implications of unaided population recoveries for future species
conservation programmes. Demographic profiles from historical genetic signatures can provide highly
informative evidence when evaluating past and future recovery efforts for endangered species
The Kestrel software for simulations of morphodynamic Earth-surface flows
No full text<p>Software archive for the Kestrel source code. Kestrel is a code for simulating shallow flows over the Earth's surface, particularly in situations which feature significant exchange of sediment with the underlying topography (morphodynamics). Designed to be a flexible research tool, Kestrel supports simulations over arbitrary surfaces and a variety of different physical parametrisations for drag, erosion and deposition of sediment.</p>
<p>This deposit marks the v1.0.0 release accepted for publication in the Journal of Open Source Software.</p>
Habitat use of the Common kestrel in breeding period until summer in Nakano city, Nagano Prefecture
Full text linkA pair of Common kestrel Falco tinnunculus bred until summer in Nakano City,Nagano Prefecture. Habitat use of a female of the pair and son’s juvenile kestrel was investigated by radio-tracking. We recorded the location and the habitat use by transferring the information onto a 1:3000 map. In a breeding season in August from June, the area of the adult female home-range was 27.4ha and the juvenile male was 17.3ha.Most of the home ranges were characterized by cultivated fields,rice fields, and grasslands.Kestrels actively selected grasslands,and preyed on insects.Most of the time,kestrels performed perching hunting. The grasslands aside of the rice fields managed by grass cutting were used by hunting of kestrels.The results showed that kestrels used human activity in a breeding season until summer in these habitats.Article志賀自然教育研究施設研究業績 55 : 1-4(2018)departmental bulletin pape
Foraging habitat evaluation of Common kestrel in Nakano city, Nagano Prefecture
Full text linkCommon kestrel mainly forage voles in grasslands and farmland.Nakano city in Nagano prefecture is characterized by fruit cultivation. From the spring to summer, foraging habitat evaluation of Common kestrels was investigated by radio-tracking in Nakano City.We recorded the locations and the habitat use by transferring the information onto a 1:3000 map.In 2017 and 2018,the home-range size for one juvenile male,one adult male and one immature female was calculated using the 95% and 50% kernel method. The area of the juvenile male home-range was 12.2ha, the adult male was 1982.4ha and the immature female was 17.3ha by 95% kernel method. The area of the juvenile male home-range was 0.9ha,the adult male was 389.1ha and the immature female was 13.4ha by 50% kernel method.Kestrels actively selected rice fields than fruits garden,and preyed on voles and insects.In the spring,when the rice field was not cultivated,kestrels foraged voles by the center part of the rice field. In the summer,the grasslands sides of the rice fields managed by grass cutting were used by foraging of kestrels. We evaluated rice fields as the most important foraging habitat of Common kestrel in Nakano city.Article志賀自然教育研究施設研究業績 56 : 1-6(2019)departmental bulletin pape
Kestrel, Golf Club Road, Ashridge. Archaeological Strip, Map and Sample and Watching Brief (OASIS ID: kdkarcha1-218441)
No full textBetween April and October 2016 KDK Archaeology Ltd undertook a programme of Strip, Map and Sample excavation at Kestrel, Golf Club Road, Little Gaddesden, Hertfordshire in advance of the development of a new detached dwelling. This project was undertaken as the site is within the bounds of Area of Archaeological Significance No. 28. This exercise did not uncover any finds or features of archaeological significance and the area appears to have been truncated through previous modern development
Ecological studies on the American kestrel (Falco sparverius) in east-central Indiana
No full textThe American kestrel (Falco sparverius) population of both Harrison and Washington Townships, Delaware County, east-central Indiana, showed a decline from December, 1985 to March, 1986, stabilization, and then a rise in June and July, 1986. Surveys reflect a larger kestrel population in Harrison than in Washington Township. Sex ratios from December to July indicate a greater number of males than females in both townships. Pasture was the preferred habitat of both male and female birds. No correlation was found between numbers of kestrels sighted and weather conditions. Kestrels occupied two of six nest boxes in the area and fledged a total of ten young. U. S. Fish and Wildlife Service data on 1,617 banded kestrels were analyzed. The independent effect of banding flyway on average distance traveled between banding and recovery was not significant. The independent effect of latitude was significant for the total study population of 1,617 kestrels but was not significant for a subsample of 213 birds which exhibited true migratory movement. Sex had no effect on distance traveled. The interaction of banding flyway and latitude on distance traveled was highly significant.Thesis (D. Ed.
Home range and habitat use by breeding female Common kestrel in Nakano City, Nagano Prefecture
Full text linkMale Common kestrels select a suitable foraging area, rice fields in Nakano city, Nagano Prefecture. Females are responsible for most of the incubation and brooding, and engage in hunting after the mid-nestling stage. Here we studied the home range and the habitat use of the female Kestrel during the breeding season and compared with a male. From the spring to summer, the home range and habitat use of a pair of kestrels in Nakano City were investigated using radio-tracking method. We recorded the locations by the kestrels referring to information from radio-tracking onto a 1 : 3000 map. In 2020, the home range sizes of each individual of the kestrel pair were calculated using the minimum convex polygon method, the 95％ kernel method, and the 50％ kernel method as core areas. Home range of female were consisted of northern part including the core area and southern part. The northern one included a nesting site and rice fields with good foraging value. While the southern one had fruits gardens with lower value. The male had one small core area with a nesting site and a suitable using area, rice fields, which were included one home range. Fruits gardens including the southern home range of female showed low value of utilization, but future research and management suggested that they could become available foraging grounds.Article志賀自然教育研究施設研究業績(58) : 1-7(2021)departmental bulletin pape
Kestrel Stockings
No full textPair of 'Kestrel' stockings, seamfree and ladderproof, 'sunny tan', in original packet. Maker: Kestrel. Date: 1965 - 1969 - from the The Betty Smithers Design Collection at Staffordshire University.
Kestrel Locke's Quick Files
No full textThe Quick Files feature was discontinued and it’s files were migrated into this Project on March 11, 2022. The file URL’s will still resolve properly, and the Quick Files logs are available in the Project’s Recent Activity
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