Direct and Indirect Estimates of Peregrine Falcon Population Size in Northern Eurasia

The Auk ◽  
2000 ◽  
Vol 117 (2) ◽  
pp. 455-464 ◽  
Author(s):  
J. L. Quinn ◽  
Y. Kokorev
Keyword(s):  
Population Size ◽  
Northern Eurasia ◽  
Published Data ◽  
Peregrine Falcon ◽  
Species Overlap ◽  
Peregrine Falcons ◽  
Nesting Association ◽  
The Common ◽  
Territory Density ◽  
Post Hoc

Abstract We used two different methods to estimate the density of nesting Peregrine Falcons (Falco peregrinus) across different parts of northern Eurasia. In the “territory-density” method, we extrapolated our density estimate of 406 km2 per territory (95% CI = 295 to 650 km2 per territory) in a high-density area, the Pyasina basin on the Taymyr Peninsula, to other similar areas across the range defined by published estimates. To estimate numbers in low-density areas, we used published data that suggested that Peregrine Falcon territories occur every 1,000 km2. Based on the nesting association between Peregrine Falcons and Red-breasted Geese (Branta ruficollis), we used a second, post hoc method to provide a comparative estimate where the ranges of the two species overlap. This model was based primarily on the population ecology of the Red-breasted Goose and included parameters such as the proportion of the goose population nesting with peregrines, the proportion of peregrine pairs associated with geese, goose population size, and three other variables. Some of these variables were already known, whereas others had been estimated as part of another study. The territory-density and nesting-association methods led to estimates of 1,586 (95% CI = 991 to 2,179) and 2,417 (95% CI = 1,306 to 3,528) falcon territories, respectively, across the common range of Peregrine Falcons and Red-breasted Geese; the first method suggested a population of 3,652 falcon territories (95% CI = 2,282 to 5,018) across the entire range F. p. calidus. Although both approaches entailed several major assumptions, together they provide the only quantitative estimate of this remote population of Peregrine Falcons.

Update on the Boundaries of the Curly Birch Range

2020 ◽  
pp. 9-21
Author(s):  
L.V. Vetchinnikova ◽  
◽  
A.F. Titov ◽  
◽  
Keyword(s):  
Population Size ◽  
Natural Populations ◽  
Forest Tree ◽  
Published Data ◽  
Population Approach ◽  
Key Factors ◽  
History Of ◽  
Individual Trees ◽  
Karelian Birch

The article reports on the application of the best known principles for mapping natural populations of curly (Karelian) birch Betula pendula Roth var. carelica (Mercklin) Hämet-Ahti – one of the most appealing representatives of the forest tree flora. Relying on the synthesis and analysis of the published data amassed over nearly 100 years and the data from own full-scale studies done in the past few decades almost throughout the area where curly birch has grown naturally, it is concluded that its range outlined in the middle of the 20th century and since then hardly revised is outdated. The key factors and reasons necessitating its revision are specified. Herewith it is suggested that the range is delineated using the population approach, and the key element will be the critical population size below which the population is no longer viable in the long term. This approach implies that the boundaries of the taxon range depend on the boundaries of local populations (rather than the locations of individual trees or small clumps of trees), the size of which should not be lower than the critical value, which is supposed to be around 100–500 trees for curly birch. A schematic map of the curly birch range delineated using this approach is provided. We specially address the problem of determining the minimum population size to secure genetic diversity maintenance. The advantages of the population approach to delineating the distribution range of curly birch with regard to its biological features are highlighted. The authors argue that it enables a more accurate delineation of the range; shows the natural evolutionary history of the taxon (although it is not yet officially recognized as a species) and its range; can be relatively easily updated (e.g. depending on the scope of reintroduction); should be taken into account when working on the strategy of conservation and other actions designed to maintain and regenerate this unique representative of the forest tree flora.

scholarly journals Unbiased estimation of linkage disequilibrium from unphased data

2019 ◽  
Author(s):  
Aaron P. Ragsdale ◽  
Simon Gravel
Keyword(s):  
Linkage Disequilibrium ◽  
Population Size ◽  
Evolutionary History ◽  
Unbiased Estimation ◽  
Sequencing Data ◽  
Unbiased Estimators ◽  
Population Size Estimates ◽  
Wide Range ◽  
The Common ◽  
Size Estimates

AbstractLinkage disequilibrium is used to infer evolutionary history and to identify regions under selection or associated with a given trait. In each case, we require accurate estimates of linkage disequilibrium from sequencing data. Unphased data presents a challenge because the co-occurrence of alleles at different loci is ambiguous. Commonly used estimators for the common statistics r2 and D2 exhibit large and variable upward biases that complicate interpretation and comparison across cohorts. Here, we show how to find unbiased estimators for a wide range of two-locus statistics, including D2, for both single and multiple randomly mating populations. These provide accurate estimates over three orders of magnitude in LD. We also use these estimators to construct an estimator for r2 that is less biased than commonly used estimators, but nevertheless argue for using rather than r2 for population size estimates.

Gastrointestinal helminth parasites of the common wallaroo or euro, Osphranter robustus (Gould) (Marsupialia: Macropodidae) from Australia

2020 ◽  
Vol 94 ◽  
Author(s):  
I. Beveridge
Keyword(s):  
Parasite Species ◽  
Parasite Fauna ◽  
Eastern Coast ◽  
Published Data ◽  
Helminth Parasites ◽  
Northern Australia ◽  
Gastrointestinal Helminth ◽  
High Prevalence ◽  
The Common ◽  
Specific Species

Abstract The gastrointestinal helminth parasites of 170 common wallaroos or euros, Osphranter robustus (Gould), collected from all mainland states in which the species occurs as well as the Northern Territory, are presented, including previously published data. A total of 65 species of helminths were encountered, including four species of anoplocephalid cestodes found in the bile ducts and small intestine, and 61 species of strongylid nematodes, all but two of which occurring in the stomach, and with the remainder occurring in the terminal ileum, caecum and colon. Among the mainland subspecies of O. robustus, 52 species of helminths were encountered in O. r. robustus, compared with 30 species in O. r. woodwardi and 35 species in O. r. erubescens. Of the parasite species encountered, only 17 were specific to O. robustus, the remaining being shared with sympatric host species. Host-specific species or species occurring in O. robustus at a high prevalence can be classified as follows: widely distributed; restricted to northern Australia; restricted to the northern wallaroo, O. r. woodwardi; found only in the euro, O. r. erubescens; found essentially along the eastern coast of Australia, primarily in O. r. robustus; and species with highly limited regional distributions. The data currently available suggest that the acquisition of a significant number of parasites is due to co-grazing with other macropodids, while subspeciation in wallaroos as well as climatic variables may have influenced the diversification of the parasite fauna.

Estimates of the size of winter flocks of the Pied Currawong, Strepera graculina (Shaw) from mark -recapture data - a new approach

1968 ◽  
Vol 16 (1) ◽  
pp. 27 ◽  
Author(s):  
JL Readshaw
Keyword(s):  
Population Size ◽  
Emigration And Immigration ◽  
New Method ◽  
Random Numbers ◽  
Sampling Effort ◽  
Mark Recapture ◽  
New Approach ◽  
The Common ◽  
Winter Flocks ◽  
Common Situation

Banding records were used to estimate the size of non-breeding winter flocks of the pied currawong, Strepera graculina, at Albury, N.S.W., during 1964 and 1965. A new method of analysing mark-recapture data is compared with conventional methods, and it is shown that the flocks contained between 500 and 1000 birds in both years. In 1964, the new method provided information on emigration and immigration that was not apparent when the data were treated in the conventional way. The new approach considers the common situation in which a population (flock) is sampled continuously by catching one member (bird) at a time, marking (banding) it, and returning it to the population. For closed populations, the population size was estimated by a method involving cumulative catch and recapture data. Subsequently, this method was successfully tested by simulating the sampling of 20 "populations" of 10,000 random numbers with a computer. The method also provided a simple way of controlling sampling effort based on recapture data to obtain any desired precision in the estimation of population size.

Variation in Peregrine Falcon Eggs

The Auk ◽  
1984 ◽  
Vol 101 (3) ◽  
pp. 578-583 ◽  
Author(s):  
William A. Burnham ◽  
James H. Enderson ◽  
Thomas J. Boardman
Keyword(s):  
Embryonic Development ◽  
Representative Sample ◽  
Shell Thickness ◽  
Egg Size ◽  
Peregrine Falcon ◽  
Eggshell Thickness ◽  
Fresh Weight ◽  
Initial Weight ◽  
Future Studies ◽  
Peregrine Falcons

Abstract Eggs collected from captive and wild Peregrine Falcons (Falco peregrinus) were used to examine variation in eggshell thickness, length, breadth, and initial weight to resolve questions about eggshell data from wild falcons. For captive falcons, shell thickness of first clutches did not change over the years a falcon laid or with embryonic development. Eggshells in third clutches, but not second clutches, were significantly thinner than those from first clutches. Greatest variation in shell thickness existed between eggs within a clutch and did not differ significantly between wild and captive eggs. Entire clutches of wild falcons should be represented in future studies to maximize the chance of obtaining a representative sample in regard to shell thickness. Egg size (L, B, and fresh weight) decreased over the years a captive falcon laid. A significant decrease in size (B and fresh weight) also occurred in second and third clutches laid the same year. Ratcliffe's Index generally appeared to be a reliable indicator of shell thickness in captive-laid eggs.

Examination of the relationship between inbreeding and population size

1985 ◽  
Vol 17 (1) ◽  
pp. 97-106 ◽  
Author(s):  
John H. Relethford
Keyword(s):  
Population Structure ◽  
Linear Regression ◽  
Population Size ◽  
Effective Population Size ◽  
Linear Regression Model ◽  
Historical Change ◽  
Human Populations ◽  
Effective Population ◽  
The Common ◽  
The Relationship

SummaryA method is presented for examining the relationship between effective population size and accumulated random inbreeding in human populations. For a set of populations, the inverse of inbreeding is regressed on effective population size using a linear regression model. This procedure allows testing of several hypotheses regarding the common and unique influences on population structure. Deviations from the expected curve suggest demographic or historical change. This method is applied to surname data from nine Irish isolates. The results show that the method is very useful in assessing differential influences on population structure.

scholarly journals Holocene and Common Era sea level changes in the Makassar Strait, Indonesia

2019 ◽  
Author(s):  
Maren Bender ◽  
Thomas Mann ◽  
Paolo Stocchi ◽  
Dominik Kneer ◽  
Tilo Schöne ◽  
...  
Keyword(s):  
Sea Level ◽  
Published Data ◽  
Glacial Isostatic Adjustment ◽  
Sea Level Changes ◽  
Relative Sea Level ◽  
Isostatic Adjustment ◽  
Thousand Islands ◽  
The Common ◽  
Common Era ◽  
Spermonde Archipelago

Abstract. Indonesia is a country composed of several thousand islands, many of them small, low-lying and densely inhabited. These are, in particular, subject to high risk of inundation due to future relative sea level changes. The Spermonde Archipelago, off the coast of Southwest Sulawesi, consists of more than 100 small islands. This study presents a dataset of 24 sea-level index points from fossil microatolls, surveyed on five islands in the Spermonde Archipelago and compares these new results with published data from the same region and with relative sea level predictions from different Glacial Isostatic Adjustment (GIA) models. The newly surveyed fossil microatolls are located around the islands of Tambakulu, Suranti (both ~ 60 km offshore of Makassar city), Bone Batang and Kodingareng Keke (both located in the center of the Archipelago) and Sanrobengi (located ~ 20 km south-southwest of Makassar). Results from the near- and mid-shelf islands indicate that relative sea level between 4 to 6 ka BP was less than one meter above present sea level. The only exception to this pattern is the heavily populated island of Barrang Lompo, where we record a significant subsidence when compared to the other islands. These new results support the conclusions from a previous dataset and are relevant to constrain late Holocene ice melting scenarios. Samples from the two outer islands (Tambakulu and Suranti) yielded ages spanning the Common Era that represent, to our knowledge, the first reported for the entire Southeast Asian region.

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 The National Survey of Mental Health and Well-Being in Australia: Impact on Policy

2002 ◽  
Vol 47 (9) ◽  
pp. 819-824 ◽  
Author(s):  
Scott Henderson
Keyword(s):  
Mental Health ◽  
Mental Disorders ◽  
National Survey ◽  
Common Mental Disorders ◽  
Well Being ◽  
Point Prevalence ◽  
Published Data ◽  
Years Of Life Lost ◽  
The Common ◽  
Health And Well Being

Objective: To provide a synopsis of the 3-part National Survey of Mental Health and Well-Being in Australia and to examine the yield in terms of policy and other changes in mental and general health services. Method: Published data are examined, and a commentary is provided on service-delivery issues that the data have revealed. Results: One-year prevalence estimates for the common mental disorders, defined according to ICD-10 criteria and assessed using the automated version of the Composite International Diagnostic Interview (CIDI-A), have indicated rates similar to those of other countries (17.7%). Alarmingly high rates were found for alcohol and substance abuse in young persons, especially among young men. The number of years of life lost owing to disability attributable to mental disorders exceeds the number lost owing to cardiovascular disease and cancer. Only 35% of persons with 1 or more of the common mental disorders had sought help in the 12 months prior to interview. The point prevalence for mental health problems was 14% for persons aged 4 to 17 years. The point prevalence for psychotic disorders was 4.7 per 1000. An encouraging finding is that 81% of affected individuals had been to their general practitioner (GP) in the last year. However, only 20% had participated in any rehabilitation program in the past year. Conclusions: The Survey results are based on a national population sample, not on individuals reaching services. They have therefore proved to be of great value in influencing policy at federal and state levels and may have contributed to increased funding for both services and research.

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