scholarly journals The Danish Peregrine Falcon population: Reestablishment and eggshell thinning

2018 ◽  
Vol 26 (2) ◽  
pp. 159-163 ◽  
Author(s):  
Niels Peter Andreasen ◽  
Knud Falk ◽  
Søren Møller
Keyword(s):  
Power Plants ◽  
Small Population ◽  
Peregrine Falcon ◽  
Falco Peregrinus ◽  
Nest Boxes ◽  
Historic Time ◽  
Peregrine Falcons ◽  
Eggshell Thinning ◽  
Breeding Attempt

Abstract Denmark being a country with only a few suitable steep nesting cliffs has only harboured a small population of Peregrine Falcons (Falco peregrinus) in historic time. In the previous century, the population gradually declined due to persecution, egg and young collection, and pollution. The last breeding attempt in the 20th century occurred in 1972 in southeastern Denmark. No new breeding attempts were recorded in Denmark until 2001 but since then the population has gradually increased – most rapidly since 2012 – to a peak of 24 territorial pairs in 2018; some of them breeding on man-made structures (nest boxes at bridges and power plants). Here we update the information on the reestablishment of the Peregrine Falcon in Den-mark, including origin and dispersal, reproduction, and eggshell thinning.

scholarly journals Population trends and diversification of breeding habitats of Peregrine Falcon (Falco peregrinus) in the Czech Republic since 1990

2018 ◽  
Vol 26 (2) ◽  
pp. 121-129
Author(s):  
Václav Beran ◽  
Josef Vrána ◽  
David Horal
Keyword(s):  
Czech Republic ◽  
Breeding Habitat ◽  
Peregrine Falcon ◽  
German Population ◽  
Falco Peregrinus ◽  
The Czech Republic ◽  
Nest Boxes ◽  
Industrial Buildings ◽  
The 1960S ◽  
Population Restoration

Abstract The population of the Peregrine Falcon (Falco peregrinus) in the Czech Republic recovered from a nearly total extinction during the 1960s and 1980s (0­3 breeding pairs) and the first successful breeding after this interval was confirmed in 1995. The increase of the population size accelerated after 2000 and it is still growing despite the limited amount of suitable natural breeding opportunities. There were 89 known pairs in 2016, 70 of them were proven to breed with altogether at least 121 reared young. Several breeding attempts on historical buildings in city­centres were recorded up to 2002 (in Prague and Pilsen), but this breeding habitat was abandoned later. More and more pairs are nowadays breeding on industrial buildings. The first breeding on a power plant chimney, 300m above the ground was discovered in 2010. Moreover, 16 breeding pairs were found on industrial buildings in 2016 (mainly tall chimneys or cooling towers and power­plant buildings), all of them breeding in nest boxes. The colonization of industrial buildings started in western part of the Czech Republic and continues eastwards every year. Currently, the easternmost colonized building is in Mladá Boleslav. We have no recent tree­breeding pairs and all eight published historical cases are at least doubtful. Most of the observed Peregrines ringed abroad came from Germany, indicating a strong influence of German population on restoration of the population in the Czech Republic. Within these recoveries, some of Peregrines were released in the tree­breeding population restoration project in Germany and Poland, but all these birds bred on rocks.

Eggshell Thinning in the Peregrine, Falco Peregrinus (Aves: Falconidae), in Australia.

1979 ◽  
Vol 6 (2) ◽  
pp. 217 ◽  
Author(s):  
P Olsen ◽  
J Olsen
Keyword(s):  
Peregrine Falcon ◽  
Falco Peregrinus ◽  
Eggshell Thinning

From measurement of 472 eggs of the peregrine falcon (Falco peregrinus) collected in Australia between 1885 and 1977 inclusive, shells were thinner by 10.4 to 38% after 1947-49 and corresponded with the introduction of DDT into Australia. Victoria seemed to have the greatest mean thinning.

scholarly journals Morphological Characteristics of the Sperm of the Peregrine Falcon (Falco peregrinus) during the Reproductive Season

2021 ◽  
Vol 8 (9) ◽  
pp. 169
Author(s):  
Andrea Oliveira ◽  
Felisa Martínez ◽  
Lydia Gil ◽  
Victoria Luño
Keyword(s):  
Optical Microscopy ◽  
Morphological Characteristics ◽  
Reproductive Season ◽  
Peregrine Falcon ◽  
Sperm Cells ◽  
Falco Peregrinus ◽  
Bright Field ◽  
Morphological Abnormalities ◽  
Peregrine Falcons ◽  
Initial Stage

The morphological characteristics of different sperm cells (normal, abnormal, and immature) in the peregrine falcon during the reproductive season were analysed. We also classified the main sperm defects found in semen. Semen samples were collected from mature peregrine falcons via cloacal massage and stained with Diff-Quik stain. The percentages of normal, abnormal, and immature sperm cells were determined by bright-field optical microscopy. The number of normal spermatozoa were greater at the initial stage and subsequently decreased during the middle and later stages of the reproductive season (p < 0.01). In contrast, the percentage of abnormal spermatozoa increased significantly in the middle and end stages of the reproductive season (p < 0.05), whereas the proportion of immature spermatozoa remained stable during the study. Head defects represented the greatest proportion of morphological abnormalities, followed by the defects in the tail and midpiece regions. A small percentage of multiple defects and cytoplasmic droplets were also observed in the falcon spermatozoa. The findings of this study might be important for the development of future conservation protocols for falcon sperm.

scholarly journals Diet of Peregrine Falcons Falco peregrinus in the urban environment of Maribor (NE Slovenia)

Acrocephalus ◽  
2018 ◽  
Vol 39 (176-177) ◽  
pp. 39-43
Author(s):  
Franc Janžekovič ◽  
Franc Bračko ◽  
Aleš Tomažič ◽  
Tina Klenovšek ◽  
Nastja Mencinger
Keyword(s):  
Urban Environment ◽  
Dietary Habits ◽  
Columba Livia ◽  
Sturnus Vulgaris ◽  
Peregrine Falcon ◽  
Body Parts ◽  
Falco Peregrinus ◽  
Feral Pigeons ◽  
Peregrine Falcons ◽  
Nesting Site

Abstract The article presents dietary habits of the Peregrine Falcon in the urban environment of Maribor. The diet was studied with an analysis of prey remnants at the nesting site. In October 2015, prey remnants were collected after the nesting in and around the nest built on top of the grain storage silo. Prey remnants, mostly bones and feathers, were sorted into body parts: skull with the beak, wings, and legs. Wings were the most numerous remnants with 41.7%, followed by legs and skulls with 28.1% each. In total, 96 units of prey were found, belonging to five different species of birds. The number of specimens and biomass was dominated by Feral Pigeons Columba livia domestica with 64.6% in number and 89.5% in prey biomass. The second most frequent prey of falcons were Starlings Sturnus vulgaris.

scholarly journals Peregrine Falcon Eggs: Egg Size, Hatchling Sex, and Clutch Sex Ratios

The Condor ◽  
2003 ◽  
Vol 105 (2) ◽  
pp. 327-335 ◽  
Author(s):  
William Burnham ◽  
Calvin Sandfort ◽  
James R. Belthoff
Keyword(s):  
New Mexico ◽  
Egg Size ◽  
Resource Competition ◽  
Sex Ratios ◽  
Peregrine Falcon ◽  
Falco Peregrinus ◽  
Local Resource Competition ◽  
Local Resource ◽  
Peregrine Falcons ◽  
Falco Peregrinus Anatum

AbstractEggs (n = 367) collected from wild Peregrine Falcon (Falco peregrinus anatum) nests between 1976 and 1990 in Colorado and New Mexico were artificially incubated and hatched. We retrospectively examined these data for variation in egg length, breadth, and initial mass of hatchlings to resolve questions about relationships among egg size, chick size, and sex; and egg size related to first and second clutches and years. Egg length and breadth were significantly related to chick mass at hatching. Neither egg size nor hatchling mass were related to sex. Egg breadth slightly increased and then decreased over the years eggs were collected, which possibly reflects a re-established and then aging wild falcon population or other environmental variation. We also evaluated clutch sex ratios relative to theory based on sexual size dimorphism and local resource competition. Sex ratios did not significantly differ from 1:1 within first or second clutches separately or when combined. Thus, Peregrine Falcons in this population apparently did not skew clutch sex ratios in accordance with local resource competition or Fisherian theory.Huevos de Halcones Peregrinos: Tamaño, Sexo de los Pichones y Proporción de Sexos en la NidadaResumen. Huevos (n = 367) colectados de nidos silvestres de halcones peregrinos (Falco peregrinus anatum) entre 1976 y 1990 en Colorado y New Mexico fueron incubados artificialmente hasta eclosionar. Examinamos esos datos retrospectivamente en cuanto a la variación en la longitud y ancho del huevo y el peso inicial de los pichones para contestar preguntas sobre las relaciones entre tamaño del huevo, tamaño del pichón y sexo, y entre el tamaño del huevo con relación a primeras y segundas nidadas y años. La longitud y el ancho del huevo estuvieron significativamente relacionados con la masa del pichón al eclosionar. El tamaño del huevo y el peso del pichón no estuvieron relacionados con el sexo. El ancho de los huevos aumentó ligeramente y luego disminuyó a través de los años en que los huevos se colectaron, lo que posiblemente refleja una población silvestre de halcones re-establecida y posteriormente senescente, u otro tipo de variación ambiental. También evaluamos la proporción de sexos en las nidadas con relación a la teoría basada en el dimorfismo sexual de tamaño y la competencia local por recursos. Las proporciones de sexos no difirieron significativamente de 1:1 entre primeras o segundas nidadas separadamente o de forma combinada. Por tanto, los halcones peregrinos en esta población aparentemente no sesgaron la proporción de sexos en sus nidadas de acuerdo a la competencia local por recursos o a la teoría Fisheriana.

ORGANOCHLORINE RESIDUES AND EGGSHELL THINNING IN THE PEREGRINE FALCON FALCO PEREGRINUS MINOR IN ZIMBABWE

Ostrich ◽  
1995 ◽  
Vol 66 (2-3) ◽  
pp. 69-73 ◽  
Author(s):  
R. R. Hartley ◽  
I. Newton ◽  
M. Robertson
Keyword(s):  
Peregrine Falcon ◽  
Falco Peregrinus ◽  
Eggshell Thinning

scholarly journals Conservation genetics of regionally extinct peregrine falcons (Falco peregrinus) and unassisted recovery without genetic bottleneck in southern England

2020 ◽  
Author(s):  
Angela Weaving ◽  
Hazel A. Jackson ◽  
Michael K. Nicholls ◽  
Jon Franklin ◽  
Rodrigo Vega
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Captive Breeding ◽  
Genetic Erosion ◽  
Peregrine Falcon ◽  
Falco Peregrinus ◽  
Southern England ◽  
Population Crash ◽  
Peregrine Falcons ◽  
Genetic Diversity And Structure

AbstractThe peregrine falcon (Falco peregrinus) has been affected by persecution, pollution, trade and habitat degradation, but it is considered a flagship conservation success story because of successful reintroductions. However, in the UK there were never formal reintroduction programmes for peregrine falcons, and it appears that UK populations – and specifically the Sussex peregrines of the English south coast – recently recovered from a population crash unassisted. To study this, we obtained samples from contemporary populations in southern England, Ireland, continental Europe, domestic-bred peregrine falcons, and from England pre-population crash. Using microsatellite and mtDNA control region data, the genetic diversity and structure, signatures of genetic bottlenecks, and potential origin of the Sussex peregrines was investigated. We found low levels of genetic diversity across all peregrine falcon populations, low but significant genetic differentiation among all populations, and a few private alleles, indicating some level of genetic structure in European peregrines. Although we could not pinpoint the origin of the Sussex peregrines, the data suggests that it is not likely to have originated from escaped domestic birds or from adjacent European populations. The results obtained here parallel other studies on peregrines elsewhere showing low genetic diversity but genetic structure. We conclude that not enough time elapsed for genetic erosion to occur due to the population bottleneck, and that at least for the Sussex peregrines there is no need for genetic conservation by wild-take and subsequent captive breeding programmes as long as current protection measures remain in place.

scholarly journals Restoration of the tree-nesting Peregrine Falcon (Falco peregrinus) population in the Volga-Ural Region

2018 ◽  
Vol 26 (2) ◽  
pp. 254-258
Author(s):  
Alexey Pazhenkov ◽  
Igor Karyakin ◽  
Denis Afanasyev ◽  
Alexandra Krivopalova ◽  
Elena Pazhenkova
Keyword(s):  
Behavior Pattern ◽  
Ural Region ◽  
Nesting Behavior ◽  
Peregrine Falcon ◽  
Biological Factors ◽  
Ural Mountains ◽  
Falco Peregrinus ◽  
Peregrine Falcons ◽  
Volga Ural Region

Abstract We have applied the method of a forming tree-nesting behavior pattern in the chicks of the cliff-nesting Peregrine Falcon. In June 2016 and 2017, in the Southern Ural Mountains and Bugulma-Belebey Upland, we discovered four nests of Peregrine Falcons, which were threatened by destruction due to various anthropogenic and biological factors. For preventing the death of the broods, the chicks were transferred from the occupied nesting niches in the rock cliffs to nesting platforms. On nesting platforms they spent from 3 to 12 days where they were fed by adults regularly. All four broods (9 young) flew out successfully and demonstrated typical behavior for the Peregrines of their age. Adults fed fledglings and taught them to hunt.

scholarly journals Kleptoparasitism by Bald Eagles (Haliaeetus leucocephalus) as a factor in reducing Peregrine Falcon (Falco peregrinus) predation on Dunlin (Calidris alpina) wintering in British Columbia

2015 ◽  
Vol 129 (2) ◽  
pp. 159 ◽  
Author(s):  
Dick Dekker ◽  
Mark C. Drever
Keyword(s):  
British Columbia ◽  
River Valley ◽  
Bald Eagle ◽  
Haliaeetus Leucocephalus ◽  
Peregrine Falcon ◽  
Fraser River ◽  
Falco Peregrinus ◽  
Bald Eagles ◽  
Calidris Alpina ◽  
Peregrine Falcons

Kleptoparasitism, or food piracy, is common in a wide range of taxa, particularly among predators, with the larger species forcing smaller species to surrender their catch. The Bald Eagle (Haliaeetus leucocephalus) is known to rob Peregrine Falcons (Falco peregrinus) of just-caught prey. We present time series of kleptoparasitic interactions between eagles and peregrines hunting Dunlin (Calidris alpina) that were wintering at Boundary Bay in the Fraser River valley, British Columbia. In 1108 hours of observation during January, intermittently between 1994 and 2014, we recorded 667 sightings of Peregrine Falcons, including 817 attacks on Dunlin resulting in 120 captures. The population of wintering Bald Eagles in the study area increased from about 200 in 1994 to 1800 in 2014, while the rate of kleptoparasitism at the expense of peregrines increased from 0.05 to 0.20. The increase in the number of Bald Eagles coincided with a decline in January sightings of Peregrine Falcons, which suggests that some falcons may have left the study area because of interference from eagles. The decrease in Peregrine Falcon numbers can be expected to have led to reduced predation risk for Dunlins. Christmas Bird Counts conducted in the Fraser River Valley have underscored the fluctuation in eagle and peregrine numbers reported here.

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