Absence of negative effect of GPS‐tags on survival and breeding success in a long‐lived territorial raptor

Ibis, Journal Year: 2025, Volume and Issue: unknown

Published: March 19, 2025

GPS tracking has enabled significant advances in the study of animal movements such as migration and habitat use. However, devices can affect behaviour tagged individuals, especially for flying animals birds, may ultimately impair their reproduction and/or survival. While numerous studies have investigated potential negative effects GPS‐tags on few simultaneously looked at these survival, with latter sometimes suffering from methodological flaws. This GPS‐tagging breeding success survival a medium‐sized raptor, Bonelli's Eagle Aquila fasciata . Forty‐five adults were equipped backpack‐mounted representing 1.2–3.5% individual body mass. Using recently developed capture–mark–recapture model that accounts differences detectability between types tags (metal ring, coloured ring or GPS), our results showed no GPS‐tagged banded individuals. Overall, we did not observe deleterious would warn against use this species, other medium‐to‐large raptors, given relevant information they might provide conservation.

Language: Английский

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Breeding spatial behavior of an Iberian dimorphic raptor (Circus cyaneus) based on GPS tracking

Journal of Ethology, Journal Year: 2025, Volume and Issue: unknown

Published: April 18, 2025

Language: Английский

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Both movements and breeding performance are affected by individual experience in the Bonelli's eagle Aquila fasciata

Ecology and Evolution, Journal Year: 2024, Volume and Issue: 14(7)

Published: July 1, 2024

Movement is a key behaviour to better understand how individuals respond their environment. behaviours are affected by both extrinsic factors that face, such as weather conditions, and intrinsic factors, sex experience. Because of the energy costs it entails, movement can have direct consequences on an individual's demographic parameters-and ultimately population dynamics. However, relationship between daily parameters breeding performance poorly known, in particular for central place forager territorial species. We investigated here link French Bonelli's eagle (

Language: Английский

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Fifteen days are enough to estimate home-range size in some long-lived resident eagles

Journal of Ornithology, Journal Year: 2022, Volume and Issue: 163(3), P. 849 - 854

Published: April 18, 2022

Language: Английский

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

Diversity, Journal Year: 2022, Volume and Issue: 14(12), P. 1082 - 1082

Published: Dec. 8, 2022

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

Language: Английский

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The clutch size, incubation behavior of Reeves's Pheasant (Syrmaticus reevesii) and their responses to ambient temperature and precipitation

Avian Research, Journal Year: 2024, Volume and Issue: 15, P. 100168 - 100168

Published: Jan. 1, 2024

Weather conditions play a pivotal role in embryo development and parental incubation costs, potentially impacting the clutch size behavior of birds. Understanding these effects is crucial for bird conservation. Reeves's Pheasant (Syrmaticus reevesii) threatened species endemic to China, which characterized by female-only incubation. However, there lack information regarding impact weather on this species. Using satellite tracking, we tracked 27 wild female Pheasants from 2020 2023 Hubei Province, China. We explored their behavior, as well responses ambient temperature precipitation. Clutch averaged 7.75 ± 1.36, had an association with average daily precipitation during egg-laying period, was linked breeding attempts. Throughout females took 0.73 0.46 recesses every 24 h, recess duration 100.80 73.37 min nest attendance 92.98 5.27%. They showed unimodal pattern departures peaked primarily between 13:00 16:00. Furthermore, rarely left nests when high. Recess were influenced interaction mean precipitation, day Additionally, positive correlation duration. These results contribute valuable insights into life-history features endangered

Language: Английский

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Laying date depends on territorial breeders’ age, climatic conditions and previous breeding success: a long-term study (2004–2021) with Bonelli’s eagle in Spain

Journal of Ornithology, Journal Year: 2024, Volume and Issue: 165(3), P. 725 - 735

Published: March 22, 2024

Abstract Adjustment of reproductive timing within the annual cycle is a crucial issue for both offspring and parents’ survival, breeding success. Early laying date closely related to successful outcome better survival. Obtaining long datasets on threatened long-lived species’ performance can contribute their conservation. Using field observations telemetry information, here we analyse how an endangered raptor varies with nest characteristics, individual factors climatic variables during 18-year (2004–2021) study period in eastern Spain. To this end, estimated environmental affect date. Our results showed that average our area took place February 17th. Laying no trend period. Nests placed higher elevations delayed dates. Territories occupied by adults previous experience high brood size earlier Current year was highly correlated Colder territories minimum temperature December were negatively highlight importance experienced birds able adjust reproduction maximise biological fitness. High adult mortality allows sub-adults settle as breeders jeopardises persistence. Therefore, reduction territorial outmost improve conservation status declining species such Bonelli’s eagle ( Aquila fasciata ).

Language: Английский

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Breeders’ age, nest-site characteristics and climatic conditions but not density-dependent effects determine Bonelli’s Eagle breeding performance: A long-term study (2002–2021)

Ornithological Applications, Journal Year: 2023, Volume and Issue: 126(1)

Published: Sept. 11, 2023

Abstract The conservation of endangered species is a crucial topic in biology due to the important ecological roles these play their respective ecosystems. Top predators are particularly vulnerable variation environmental conditions. Bonelli’s Eagle (Aquila fasciata) long-lived bird prey that fulfills its role as top predator Mediterranean ecosystems, but overall population has declined Iberian Peninsula recent decades. As with other species, reaches maximum fitness at maturity, highlighting importance assessing how intrinsic and extrinsic factors affect dynamics over time. In this study, we conducted annual surveys subpopulation eastern from 2002 2021. Our results indicate large decline observed number occupied territories, fledged chicks, successful pairs not negative density-dependent effects rather influenced by various demographic factors. These include breeders’ age, nest-site characteristics, climatic conditions, previous breeding costs. We found productivity was higher territories high winter precipitation temperatures, well coastal areas, leading earlier laying dates. Additionally, presence subadult individuals pair decreased performance. Interestingly, variability fledglings each territory driven Prioritizing efforts mitigate adult mortality conserve suitable habitats becomes imperative halt ongoing also enhance productivity, ultimately facilitating restoration levels.

Language: Английский

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Quantifying mating behaviour using accelerometry and machine learning: challenges and opportunities

Animal Behaviour, Journal Year: 2023, Volume and Issue: 207, P. 55 - 76

Published: Nov. 16, 2023

Accelerometry and machine learning are powerful tools for gaining in-depth information about animal behaviour. However, such methods rarely used to quantify behaviours that contribute mating success, as intrasexual competition, courtship copulation. In part, this is probably due the inherent challenges of classifying can be brief infrequent, not necessarily exhibited by all individuals. study, we triaxial accelerometry machine-learning captive male ruffs, Calidris pugnax. The ruff a polymorphic, lekking shorebird with highly skewed success. Mating behaviour in ruffs includes ritualized postures distinguished during observations. Using system case (1) describe possible approaches behaviour; (2) compare classification performance three supervised methods: random forests, hidden Markov models neural networks; (3) highlight potential pitfalls cause overestimation model performance; (4) offer suggestions avoiding these pitfalls. our some from nonmating high precision sensitivity (>75%), but only when trained tested on same individuals within timeframe. Estimates were much poorer future data or different Nevertheless, even individuals, provided reasonably accurate estimate which males invested more time overall. Here, provide an end-to-end workflow accelerometry, including recommendations, considerations code. Although posture-based proved challenging distinguish, show promise displays associated distinctive, dynamic movements.

Language: Английский

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Effect of nest composition, experience and nest quality on nest-building behaviour in the Bonelli’s Eagle

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: March 9, 2022

Abstract In bi-parentally built nests, there is evidence to suggest that nests are extended phenotypic signals accurately indicate the quality of building parent/s. Raptors often use a variety materials build their (natural, such as branches, but also non-natural objects), presumably due insulating properties, suitability advertise occupancy nest, and decrease pathogen parasite loads. However, in raptors where both sexes collaborate nest construction, it unclear whether (taking amount material carried potential predictor) an indicator parental quality, effort expended by could constitute honest signal partners. Between 2011 2016, we monitored 16 Bonelli’s Eagles ( Aquila fasciata ), examined data on sex, type brought breeding experience, timing, nest-building investment prior egg-laying from 32 identifiable during pre-laying period investigate relative contribution gathered. Our results sex not determining factor effort, females did increase response male’s contribution, supply period. contrast, our models showed that: (1) supplied varied significantly throughout (2) was determined individual experience quality. Therefore, study suggests male behaviour cannot be considered signal. The differential hard green early late stages period, fact more experienced individuals contributed larger low discussed contexts signaling conspecifics competitors ectoparasite loads

Language: Английский

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