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3 pages, 179 KiB

Open AccessEditorial

Conservation and Ecology of Raptors: Introduction to the Special Issue

by Dobromir Dobrev, Vladimir Dobrev and Dimitar Demerdzhiev

Diversity 2023, 15(8), 889; https://doi.org/10.3390/d15080889 - 27 Jul 2023

Viewed by 955

Abstract

Raptors are a diverse avian guild distributed worldwide and adapted to different environments [...] Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

Research

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11 pages, 4823 KiB

Open AccessArticle

Is the Northern Goshawk an Efficient Bioindicator of Avian Abundance and Species Richness in Urban Environments?

by Ülo Väli, Jaan Grosberg, Pelle Mellov, Tiiu Tali and Paweł Mirski

Diversity 2023, 15(6), 749; https://doi.org/10.3390/d15060749 - 07 Jun 2023

Cited by 1 | Viewed by 833

Abstract

Monitoring of biodiversity in expanding urban areas is an essential part of wildlife conservation. There is evidence that raptors, such as Northern Goshawks (Accipiter gentilis), are effective bioindicator species in urban areas, however, their relationship with other bird populations is not [...] Read more.

Monitoring of biodiversity in expanding urban areas is an essential part of wildlife conservation. There is evidence that raptors, such as Northern Goshawks (Accipiter gentilis), are effective bioindicator species in urban areas, however, their relationship with other bird populations is not clearly established. We asked whether activity patterns of Goshawks are a reliable indicator of wintering bird abundance and diversity in urban ecosystems. We tracked the movement of eight GPS-tagged Goshawks in the city of Tartu (Estonia) and analysed the numbers and diversity of birds in the same area using direct mapping and occasional data obtained from birdwatchers. The direct mapping approach revealed that the number of birds and avian species richness were higher in Goshawk activity hotspots than at random sites in 2022, however, no such differences were detected in 2023. Analysis of occasional citizen-collected data showed no effect of avian abundance nor species richness on the distribution of Goshawk activity. These results suggested that the movements of Goshawks may indicate the abundance and diversity of its prey, however, this relationship depends on the detection methodology. Hence, raptors are a promising bioindicator in urban environments, but results should be interpreted with caution, particularly when using citizen-collected data. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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12 pages, 755 KiB

Open AccessArticle

The White-Tailed Eagle, the Apex Predator, Adjusts Diet towards Larger Prey in Suboptimal Territories

by Paweł Mirski and Ervin Komar

Diversity 2023, 15(6), 747; https://doi.org/10.3390/d15060747 - 06 Jun 2023

Cited by 3 | Viewed by 1290

Abstract

The White-tailed eagle, an apex predator, is currently recovering its populations across Europe and has already reached high numbers in many countries. This led to the saturation of eagles in optimal habitats and their encroachment on suboptimal ones. We aimed to compare the [...] Read more.

The White-tailed eagle, an apex predator, is currently recovering its populations across Europe and has already reached high numbers in many countries. This led to the saturation of eagles in optimal habitats and their encroachment on suboptimal ones. We aimed to compare the diet of White-tailed eagles in optimal and suboptimal conditions in northeastern Poland to investigate how population development affected prey composition, which is expected to be lacking in suboptimal eagle territories. We have monitored eagle nests with trail cameras to investigate their diet objectively and precisely. In order to compare territories of different quality, we have conducted modeling of habitat suitability using data on nest locations prior to their saturation. Using recorded photos of the prey, we measured their size and estimated their weight to check if the size and biomass of the prey are comparable between optimal and suboptimal territories. We found that eagles in the latter conditions were not limited by prey biomass but turned to alternative prey and brought larger prey. The alternative prey were large birds such as White storks and Common cranes, but also chicks of other avian predators that were robbed from their nests. Most probably, eagles cope with a lack of optimal prey by ranging farther and exploring non-optimal foraging habitats. We conclude that the diet flexibility of White-tailed eagle enables him to still increase its numbers despite already high densities. Our study also shows that this species might possibly impact the White stork population, as seen in the case of the Black stork and some seabird species. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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12 pages, 1032 KiB

Open AccessArticle

Rabbits or Refuse? Landfill Use and Relevance as a Food Source for an Increasing Wintering Population of the Red Kite

by Íñigo Vicente-Hernández, Félix Martínez and Guillermo Blanco

Diversity 2023, 15(6), 704; https://doi.org/10.3390/d15060704 - 25 May 2023

Cited by 1 | Viewed by 982

Abstract

Household waste landfills represent a huge source of trophic resources for opportunistic and versatile wildlife species. Among them, the red kite (Milvus milvus) is one of the most endangered in Europe. Several studies have pointed out the importance of landfills as [...] Read more.

Household waste landfills represent a huge source of trophic resources for opportunistic and versatile wildlife species. Among them, the red kite (Milvus milvus) is one of the most endangered in Europe. Several studies have pointed out the importance of landfills as a source of food for this species during the wintering season, but the information on the frequency, seasonal and daily patterns of use, and age of red kites that exploit this food source is still insufficient to understand their actual role in conservation. In this study, we evaluated the patterns of use of household waste by overwintering red kites in southeastern Madrid, central Spain. The results showed the constant presence of relatively low numbers (<30 on average) and a reduced hourly inflow and outflow of red kites throughout the day and during the whole winter period in the studied landfill. A higher proportion of juveniles was found in the landfill than in the overall wintering population. Pellet analysis clearly shows that the diet of red kites is dominated by the wild rabbit (Oryctolagus cuniculus), which is quantitatively very relevant compared to household waste obtained from the landfill. This suggests a relatively low quantitative importance of landfills as foraging grounds for the increasing population of wintering red kites in the study area. Instead, the high regional density of wild rabbits attracts large numbers of red kites that can eventually use landfills as a non-optimal last-resort foraging option, owing to the predictability of household waste, especially for juveniles. The continuous presence of red kites in landfills likely influences an uninformed positive perception about their relevance to the conservation of the wintering population, despite risks there faced, such as collision, electrocution, and intoxication. Future research is needed to assess in depth the influence of wild rabbits in Spain on the habitat use and global population dynamics of red kites. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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18 pages, 1757 KiB

Open AccessArticle

Turnover and Natal Dispersal in the Finnish Golden Eagle (Aquila chrysaetos) Population

by Aure Kylmänen, Ekaterina Karabanina, Tuomo Ollila, Suvi Ponnikas and Laura Kvist

Diversity 2023, 15(4), 567; https://doi.org/10.3390/d15040567 - 18 Apr 2023

Cited by 3 | Viewed by 1818

Abstract

Estimating turnover in a population provides information on population dynamics, such as dispersal and mortality. Dispersal increases genetic diversity and affects the genetic structure. Golden eagles are monogamous, tend to mate for life, and have strong nest site fidelity, which suggests low turnover [...] Read more.

Estimating turnover in a population provides information on population dynamics, such as dispersal and mortality. Dispersal increases genetic diversity and affects the genetic structure. Golden eagles are monogamous, tend to mate for life, and have strong nest site fidelity, which suggests low turnover rates. Here, we first studied genetic diversity and population structure in the Finnish golden eagle population using 11 microsatellite loci and a fragment of a mitochondrial DNA control region. We found no notable changes in genetic diversity during the 15-year study period and did not discover any population structure. Then, we examined the turnover rate using chick genotypes (N = 935) by estimating relatedness between chicks born in the same territory in different years. The results showed a turnover rate of 23%, which correlated with the breeding success of the previous year. Similarly, in the absence of turnover, the pair changed nest sites within a territory after an unsuccessful breeding. In addition, our dataset also revealed natal dispersal of ten individuals. Natal dispersal distance was 110 km on average (median 98 km); however, the distance seemed to vary depending on geographical location, being greater in Northern Finland than in Southern Finland. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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11 pages, 595 KiB

Open AccessArticle

Substantial Variation in Prospecting Behaviour of Young Golden Eagles Aquila chrysaetos Defies Expectations from Potential Predictors

by Alan H. Fielding, David Anderson, Stuart Benn, Robin Reid, Ruth Tingay, Ewan D. Weston and D. Philip Whitfield

Diversity 2023, 15(4), 506; https://doi.org/10.3390/d15040506 - 01 Apr 2023

Cited by 4 | Viewed by 1438

Abstract

Natal dispersal of large raptors is poorly understood, despite being a crucial transitional life-cycle phase affecting gene flow and population dynamics. A research-gap rarely examined concerns how young dispersing raptors strategize movements towards first settlement on a prospective breeding territory. First territory settlement [...] Read more.

Natal dispersal of large raptors is poorly understood, despite being a crucial transitional life-cycle phase affecting gene flow and population dynamics. A research-gap rarely examined concerns how young dispersing raptors strategize movements towards first settlement on a prospective breeding territory. First territory settlement is a critical decision for a lifetime and can take several years. With such importance, large raptors should theoretically devote considerable effort to acquire accurate information during prospection. Nevertheless, when discovery of territorial opportunities may be difficult, but easier in vacant territories, we posit two extremes in strategizing prospection behaviours: (1) “Quick, grab it when available with limited reconnaissance,” as opposed to (2) “Slow, waiting game with frequent reconnaissance”. We analysed pre-settlement data from 37 GPS-tagged nestling golden eagles, later recorded as having settled on their first territory. The number of eagles’ unique daily visits to their later settled territories was a measure of prospection intensity. We documented substantial variation in prior visits, between less than 10 to several hundred. Analyses considered several potential predictors. We expected a positive association between number of prospecting visits and natal dispersal duration, since with more time to gather information there should be more visits. We also expected fewer prospecting visits in prior vacant territories. Neither of these expectations were supported. There was a non-significant tendency for more prospection visits by males. Our study provides novel information on a seldom-studied behaviour in a large raptor. It illustrates substantial variation in prospecting behaviour, but expectations of potential drivers behind this variation were not confirmed, urging further study. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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12 pages, 2317 KiB

Open AccessArticle

Are Roadkills Density-Dependent? Case Study of the Barn Owl (Tyto alba)

by Kobi Meyrom, Reuven Yosef and Motti Charter

Diversity 2023, 15(3), 412; https://doi.org/10.3390/d15030412 - 11 Mar 2023

Cited by 3 | Viewed by 1769

Abstract

Even though birds are some of the most common road-killed animals, it remains to be determined whether avian roadkills are related to breeding numbers and breeding success, mainly due to a lack of study areas that monitor breeding populations and roadkills. We studied [...] Read more.

Even though birds are some of the most common road-killed animals, it remains to be determined whether avian roadkills are related to breeding numbers and breeding success, mainly due to a lack of study areas that monitor breeding populations and roadkills. We studied whether barn owl breeding numbers and breeding success are related to roadkills. We monitored yearly barn owl breeding numbers (2174 breeding attempts and 1682 adults ringed) and breeding success (9380 nestlings ringed) and monitored 95 km of roads weekly for roadkills from 2009 to 2017 in the Beit Shean and Emek Yizreel Valleys, Israel. During the study period, we documented 1073 road-killed barn owls, of which 328 were ring recoveries. The highest mortality occurred between July to September, coinciding with the barn owl post-fledging period. The number of breeding pairs and the number of nestlings ringed were positively related to the total number of barn owl roadkill, the proportion of roadkill ring recoveries, and the proportion of ring recovered roadkills in the first year of their life. First-year owls represent the majority of ringed owls, accounting for 64.6%, while adult owls compose 35.4%. Notably, a substantial fraction of adult ring recoveries, encompassing 67.2%, may pertain to floaters since we did not observe these individuals as breeding adults. Even though more females were found as roadkill ring recoveries, the proportion of male/female ring recoveries from roadkills was similar to that of adults ringed at the nest boxes. This study is the first that shows that barn owl roadkills are density-dependent and demonstrate the importance of monitoring breeding and population numbers in roadkill studies. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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13 pages, 1418 KiB

Open AccessArticle

Selection of Nesting Habitat and Insular Niche Separation of Two Sympatric Aquila Species

by Maria Solanou, Eirini Trypidaki, Elisavet Georgopoulou, Konstantinos Damianakis, Afroditi Kardamaki and Stavros M. Xirouchakis

Diversity 2022, 14(12), 1136; https://doi.org/10.3390/d14121136 - 18 Dec 2022

Cited by 2 | Viewed by 1569

Abstract

Aquila chrysaetos and Aquila fasciata are two congeneric eagle species distributed in the Mediterranean region which are supposed to compete for similar breeding and foraging resources. In the present study, bioclimatic, topographic, and human-related habitat parameters were investigated for 64 and 75 nest [...] Read more.

Aquila chrysaetos and Aquila fasciata are two congeneric eagle species distributed in the Mediterranean region which are supposed to compete for similar breeding and foraging resources. In the present study, bioclimatic, topographic, and human-related habitat parameters were investigated for 64 and 75 nest sites of Golden and Bonelli’s eagles, respectively. The nests were found during fieldwork undertaken from 1995–2020. Overall, the habitat parameters that best discriminated nest site selection were associated with elevation, temperature, and land use with topographic variables being most powerful for niche separation. Univariate analysis, regression, and species distribution modeling identified a strong association of the species with altitude pinpointing the Golden eagle’s mountainous and continental character and the Bonelli’s eagle being a lowland and coastal species. Golden eagle nests were situated away from human settlements on steep cliffs in higher altitude areas with transitional woodland-shrub vegetation. In contrast Bonelli’s eagle nests were located on low-altitude warmer zones, closer to the coast and human settlements with more natural grasslands in their vicinity. The ecological niche separation of the two species was best described by altitude and temperature, though no clear-cut evidence was detected for their competitive exclusion. Inter-specific nearest neighboring distance was found statistically significant only for the Golden eagle which seems to be less tolerant in its co-existence with the Bonelli’s eagle. Conservation measures for both species should target territories under human pressure, though more research should focus on the species range use and habitat heterogeneity within overlapping territories. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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11 pages, 1138 KiB

Open AccessArticle

Home-Range Size and Space Use of Territorial Bonelli’s Eagles (Aquila fasciata) Tracked by High-Resolution GPS/GSM Telemetry

by Sara Morollón, Vicente Urios and Pascual López-López

Diversity 2022, 14(12), 1082; https://doi.org/10.3390/d14121082 - 08 Dec 2022

Cited by 6 | Viewed by 1878

Abstract

High-resolution GPS/GSM dataloggers provide spatial information of the highest quality, which outperform previous tracking methods, such as Argos telemetry or conventional VHF ground-tracking. As a result, this has improved our knowledge of home-range behavior and spatial ecology of many species, including large raptors. [...] Read more.

High-resolution GPS/GSM dataloggers provide spatial information of the highest quality, which outperform previous tracking methods, such as Argos telemetry or conventional VHF ground-tracking. As a result, this has improved our knowledge of home-range behavior and spatial ecology of many species, including large raptors. In this paper, we use high-resolution GPS/GSM dataloggers to assess the home-range size and the role of sex, season (breeding or non-breeding season), and breeding status (reproductive or non-reproductive individuals) on the space use of Bonelli’s eagle (Aquila fasciata). To this end, 51 territorial individuals (25 females and 26 males) were equipped with GPS/GSM transmitters and were tracked over 7 years (2015–2021) in eastern Spain. Overall, we recorded 4,791,080 fixes that were analyzed through kernel density methods (50%, 75%, and 95% fixed kernels). The average individual home-range size according to the 95%, 75%, and 50% kernels was 54.84 ± 20.78 km², 24.30 ± 10.18 km², and 11.17 ± 4.90 km², respectively. Overall, the home-range size of individuals occupying the same territory was similar, mainly due to the cooperative hunting behavior exhibited by the species. We did not find interannual differences in the home-range size (95% fixed kernel) of the majority of individuals, showing a strong territorial fidelity of the breeding pairs. In general, females’ home-range size was slightly smaller than males’ size due to the decrease in activity in the breeding season as a result of laying, incubation, and chick attendance at nests. No seasonal variation in the 95% kernel was found, but it was found in the 75% and 50% kernels. In regard to the breeding status, higher home-range size was recorded in the non-reproductive individuals. Moreover, we found a low neighbor overlap among the territories (4.18% ± 3.06%), which evidences a high level of intraspecific competition in the Bonelli’s eagle. Finally, this study highlights the advantages of the use of accurate telemetry information to improve our understanding of the spatial ecology of the endangered Bonelli’s eagle, which ultimately will serve to better inform management actions for its conservation. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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15 pages, 2150 KiB

Open AccessArticle

Foraging Patterns of Non-Territorial Eastern Imperial Eagle (Aquila heliaca): A Case of Successful Adaptation

by Dimitar Demerdzhiev, Ivaylo Angelov and Dobromir Dobrev

Diversity 2022, 14(12), 1060; https://doi.org/10.3390/d14121060 - 02 Dec 2022

Cited by 4 | Viewed by 1598

Abstract

The Optimal Foraging Theory predicts that, to maximize fitness, animals adapt their foraging strategy that provides the most benefit for the lowest cost, maximizing the net energy gained. While the diet of many breeding raptor populations is well known, studies on the foraging [...] Read more.

The Optimal Foraging Theory predicts that, to maximize fitness, animals adapt their foraging strategy that provides the most benefit for the lowest cost, maximizing the net energy gained. While the diet of many breeding raptor populations is well known, studies on the foraging patterns of non-territorial birds of prey (floaters) are scarce. In this study, we examined the foraging pattern of non-territorial Eastern Imperial Eagle, scrutinizing different aspects of its feeding ecology and behavior. We built a simple model of the optimal foraging strategy of floater eagles including the success of foraging as a currency as well as environmental factors such as seasons, type of prey, habitat, foraging techniques, and eagle age as a limitation affecting the foraging efficiency of birds. We found that floaters focused their diet exclusively on European Souslik, accounting for almost half (44.2%) of the eagle’s prey. Diet differences between floaters and breeders were due to higher Souslik and carrion consumption and lower Hedgehog predation by floater eagles. The diet diversity of breeding eagles (H = 3.297) was much higher than that of floaters (H = 1.748). Our model suggested that the foraging mode, habitat type, and season best explained the feeding success of non-territorial eagles (_ΔAIC = 0.00, w = 0.42). Of all explanatory factors, “Kleptoparasitism” (β² = −4.35), “Rodents” (β² = −4.52), “Pasture” (β² = 2.96), “Wheat” (β² = 4.41), “In the air” (β² = 4.16), and “Other habitats” (β² = 4.17) had a pronounced effect. The factors “Spring–summer season” (β² = −0.67) and “European Souslik” (β² = −2.76) had a marginal effect in our models. Generally, the mean success rate of attack modes used by non-territorial eagles was 0.54 ± 0.50. Floaters successfully obtained food through: kleptoparasitism (43.10%), carrion feeding (24.14%), and high soar with vertical stoop (14.66%). Several important issues for the conservation of non-territorial Eastern Imperial Eagles arose from our research. The strong relation of floaters with the European Souslik calls for specific conservation measures aimed at the conservation of this type of prey and the restoration and appropriate management of its grassland habitats. The importance of the scavenging behavior of juvenile birds requires increased control of the use of poison baits and subsequent prosecution by state institutions. Protecting the most important temporary areas, improving institutional control against the use of poison baits, and intensifying awareness-raising campaigns among pigeon-fanciers and hunters are also of crucial importance for effective species conservation. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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18 pages, 1958 KiB

Open AccessEditor’s ChoiceArticle

Does Temporal and Spatial Diet Alteration Lead to Successful Adaptation of the Eastern Imperial Eagle, a Top Predator?

by Dimitar Demerdzhiev, Zlatozar Boev, Dobromir Dobrev, Nedko Nedyalkov and Tseno Petrov

Diversity 2022, 14(11), 1000; https://doi.org/10.3390/d14111000 - 19 Nov 2022

Cited by 4 | Viewed by 1409

Abstract

Predator–prey interactions may be linked to different temporal or spatial patterns, including dynamics in prey populations. Therefore, understanding the adaptive capacity and how top predators respond to shifts in prey abundance and availability is crucial for their conservation. In this study, we investigated [...] Read more.

Predator–prey interactions may be linked to different temporal or spatial patterns, including dynamics in prey populations. Therefore, understanding the adaptive capacity and how top predators respond to shifts in prey abundance and availability is crucial for their conservation. In this study, we investigated the diet pattern of the endangered Eastern Imperial Eagle facing long-term and large-scale changes. We studied the abundance variation of its profitable prey, sousliks, and how it reflected on eagle population trajectories in a regional and temporal context. We found a significant diet alteration expressed in large decrease of brown hare (β² = −0.83), poultry (β² = −0.81), gulls (β² = −0.71), and water birds (β² = −0.57), and an obvious increase of northern white-breasted hedgehog (β² = 0.61) and doves (β² = 0.60). Raptors and owls raised their participation (β² = 0.44), but white stork and different reptiles supplied more biomass. Abundance of European souslik decreased through the studied periods (adjusted R² = 0.25, p < 0.001) which accounted for the lower proportion of this prey in the eagle’s diet. Nevertheless, the eagle population successfully adapted and significantly increased (β² = 0.97) in most of the distribution area. The trophic strategy used by this top predator related to opportunistic foraging represents an ecological advantage that allows the species to adapt to different habitats and guarantees its future. The observed prolonged diet alteration could result in a significant negative attitude among different groups such as hunters, pigeon fanciers, and poultry keepers towards eagles. Therefore, enhanced communication with key stakeholders is needed. Conservation efforts should be focused also on the preservation of the species’ main foraging habitats and the restoration of damaged ones so as to maintain the good conditions of both primary food source and subsequent prey. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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11 pages, 1110 KiB

Open AccessArticle

A Community-Level Approach to Species Conservation: A Case Study of Falco naumanni in Southern Italy

by Alessandro Ferrarini, Giuseppe Giglio, Stefania Caterina Pellegrino and Marco Gustin

Diversity 2022, 14(7), 566; https://doi.org/10.3390/d14070566 - 14 Jul 2022

Cited by 4 | Viewed by 1430

Abstract

The conservation of threatened species is prevalently oriented towards two management strategies, i.e., habitat-level and species-level approaches. The former is focused on improving the conditions of the habitat of a certain species, whereas the latter is aimed at directly strengthening the species of [...] Read more.

The conservation of threatened species is prevalently oriented towards two management strategies, i.e., habitat-level and species-level approaches. The former is focused on improving the conditions of the habitat of a certain species, whereas the latter is aimed at directly strengthening the species of interest. In this work, we adopted a different solution based on a community-level approach. Firstly, we identified the species (predators, competitors, prey) that interact with the species of interest (the lesser kestrel, Falco naumanni) in Southern Italy and mapped all of the ecological interactions among these species. Secondly, we built a simulation framework of the entire ecological network of the lesser kestrel. Thirdly, we simulated different management strategies that could increase the lesser kestrel population stock by targeting the species that interact with it. We found that the lesser kestrel in Southern Italy can be effectively protected by targeting the species interacting with the lesser kestrel, and that natural changes in the abundance of the interacting species could be used to pro-actively predict the dynamics of the lesser kestrel population. Our study demonstrates that a community-level approach to species conservation is highly appropriate on a local scale. Our methodological framework, based on qualitative modeling and what-if scenarios, can be applied in the absence of quantitative estimations of population stocks and interaction strengths. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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10 pages, 958 KiB

Open AccessArticle

Importance of Mesohabitat for Nest-Site Selection in Breeding Eagle Owls (Bubo bubo): A Multi-Scale Model

by Ezra Hadad, Dan Malkinson, Reuven Yosef, Gilad Weil and Motti Charter

Diversity 2022, 14(6), 438; https://doi.org/10.3390/d14060438 - 30 May 2022

Cited by 6 | Viewed by 1848

Abstract

Apex predators make excellent bioindicators of habitat quality and anthropogenic changes. Eagle owls (Bubo bubo) are such apex and keystone predators, who show preferential nest-site selection, usually away from human activities and habitation. However, Israel is a small country with a [...] Read more.

Apex predators make excellent bioindicators of habitat quality and anthropogenic changes. Eagle owls (Bubo bubo) are such apex and keystone predators, who show preferential nest-site selection, usually away from human activities and habitation. However, Israel is a small country with a burgeoning human population. Hence, in order to understand the habitat requirements of eagle owls in central Israel, we conducted a multi-scale model analysis on their existing nest sites between 2006 and 2010. We identified 203 successful breeding attempts at 73 different sites. Our data suggested that the breeding population of the eagle owls was limited by the availability of quality nest locations, i.e., quarries, and caves. The probability of an eagle pair breeding increased with the presence of both quarries and caves, but was not related to mesohabitat properties. In addition, eagle owl breeding densities were positively related to the number of nest localities and to the planted woodlands. Furthermore, we found that eagle owls successfully raised their young regardless of the surrounding mesohabitat and sought the presence of other potential nest sites in the vicinity of the active nest sites, most likely due to the owls’ opportunistic and generalist hunting behavior, which facilitated the consumption of a wide prey base. Appropriate nest sites (quarries and caves) appeared to increase population numbers and, therefore, should be protected Further studies should determine whether increasing artificial nest sites and reclaiming abandoned quarries could increase eagle owl numbers in a sustainable manner. Full article

(This article belongs to the Special Issue Conservation and Ecology of Raptors)

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