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

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.

Acrocephalus ◽  
2018 ◽  
Vol 39 (176-177) ◽  
pp. 39-43
Author(s):  
Franc Janžekovič ◽  
Franc Bračko ◽  
Aleš Tomažič ◽  
Tina Klenovšek ◽  
Nastja Mencinger

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.


The Condor ◽  
2003 ◽  
Vol 105 (2) ◽  
pp. 327-335 ◽  
Author(s):  
William Burnham ◽  
Calvin Sandfort ◽  
James R. Belthoff

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.


2020 ◽  
Author(s):  
Angela Weaving ◽  
Hazel A. Jackson ◽  
Michael K. Nicholls ◽  
Jon Franklin ◽  
Rodrigo Vega

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.


2018 ◽  
Vol 26 (2) ◽  
pp. 254-258
Author(s):  
Alexey Pazhenkov ◽  
Igor Karyakin ◽  
Denis Afanasyev ◽  
Alexandra Krivopalova ◽  
Elena Pazhenkova

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.


2018 ◽  
Vol 26 (2) ◽  
pp. 159-163 ◽  
Author(s):  
Niels Peter Andreasen ◽  
Knud Falk ◽  
Søren Møller

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.


2007 ◽  
Vol 34 (1) ◽  
pp. 54 ◽  
Author(s):  
Victor G. Hurley ◽  
Fiona Hogan ◽  
John G. White ◽  
Raylene Cooke

Adult peregrine falcons (Falco peregrinus macropus) have monotypic plumage and display strong reversed sexual dimorphism, with females significantly larger than males. Reversed sexual dimorphism is measurable among nestlings in the latter stages of their development and can therefore be used to differentiate between sexes. In the early stages of development, however, nestlings cannot be sexed with any degree of certainty because morphological differentiation between the sexes is not well developed. During this study we developed a model for sexing younger nestlings based on genetic analysis and morphometric data collected as part of a long-term banding study of this species. A discriminant function model based on morphological characteristics was developed for determining the sex of nestlings (n = 150) in the field and was shown to be 96.0% accurate. This predictive model was further tested against an independent morphometric dataset taken from a second group of nestlings (n = 131). The model correctly allocated sex to 96.2% of this second group of nestlings. Sex can reliably be determined (98.6% accurate) for nestlings that have a wing length of at least 9 cm using this model. Application of this model, therefore, allows the banding of younger nestlings and, as such, significantly increases the period of time over which banding can occur. Another important implication of this model is that by banding nestlings earlier, they are less likely to jump from the nest, therefore reducing the risk of injury to both the brood and the bander.


2015 ◽  
Vol 129 (2) ◽  
pp. 159 ◽  
Author(s):  
Dick Dekker ◽  
Mark C. Drever

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.


2017 ◽  
Author(s):  
Sumithra Sriram ◽  
Falk Huettmann

Abstract. Peregrine falcons (Falco peregrinus) are among the fastest members of the animal kingdom, and they are probably the most widely distributed raptors in the world; their migrations and habitats range from the tundra, mountains and some deserts to the tropics, coastal zones and urban habitats. Habitat loss, conversion, contamination, pesticides and other anthropogenic pressures are all known factors that have an adverse effect on these species. However, while peregrine falcons were removed from the list of endangered species due to rebounding populations linked with the DDT ban in many nations of the world, no accurate global distribution models have ever been developed for good conservation practice and in an open access data framework. Here we used the best-available open access peregrine falcon data from the Global Biodiversity Information Facility (GBIF.org) to obtain the first publicly available global distribution model for peregrine falcons. For that purpose, we compiled over a hundred high resolution global GIS layers (1 km pixel size) that incorporated various variables such as biological, climatic, and socio-economic predictors allowing to analysis habitat relationships in a holistic fashion and to build a generalizable model. These value-added layers have also been made available by us for the global public, free of charge, for further use and consumption in any modeling effort wanted (https://scholarworks.alaska.edu/handle/11122/7151). We created data extraction explicit in space and time also with an open source python script tool as well as with ArcGIS (via the GUI) on a PC. The obtained data cube (global, 1 km pixel, 104 GIS layers) was "mined" with the Salford Predictive Modeler (SPM) software suite, which offers one of the best platforms for data mining, to build the prediction model for robust inference. We found that peregrine falcons are widely urbanized occurring in coastal areas and also associated with riparian zones. This is the first model ever obtained using 104 predictors on a 1 km scale predicting the potential ecological niche of falcons around the world. While our model might show uncertainty for parts of Siberia, Russia, it has an assessed global accuracy of over 95 % and hence provides the currently best possible public available global prediction model for peregrine falcons, based on all available empirical data. Overlaid with the national parks of the world we found that most peregrine hotspots are actually located outside of protected areas warranting more protection efforts while global change unfolds. Finally, a nationwide assessment of the presence points taken from GBIF allows for insight as to the many signatory nations that are still in violation of the open access data sharing requirement set by the Convention of Biological Diversity (CBD) and the Budapest and Berlin Declaration.


Sign in / Sign up

Export Citation Format

Share Document