Video surveillance cameras installed on birds' nests are a cost-effective tool to study many aspects of ecology and behaviour that would otherwise be practically impossible to obtain. However, ...although most studies report neutral effects of cameras on birds, very few studies analyse in detail the potential negative effects of their use, particularly on raptors. Here, using a long-term database of a population of Bonelli's eagle (Aquila fasciata) collected from 2000 to 2022, I show how the inappropriate use of video surveillance cameras could result in negative effects on the reproduction of a threatened species through a before-and-after control-impact study design. Pairs under video surveillance showed lower productivity, lower breeding success and unusual delayed laying dates. The installation of cameras close to the laying date, coinciding with the mating phase of individuals, most of them subadult inexperienced birds; in combination to the reiteration of visits to the nests once the cameras were installed to check the system, particularly during the incubation period and early stages of breeding; and the installation of cameras in a particular area subject to constant human disturbance, might explain these results. Potential management actions to mitigate the effect of the installation of video cameras on birds' behaviour should include the need to plan the intervention dates, testing the systems beforehand under controlled conditions and adequate post-installation monitoring to avoid unnecessary disturbance to animals. Finally, I urge the scientific community to report the potential negative effects observed in their studies, especially if the target species are threatened with extinction.
Cosmetic coloration is not a common phenomenon among bird species. Adult Bearded Vultures Gypaetus barbatus typically show orange coloration in head, chest, belly and tarsus feathers that is the ...result of mud baths in ferruginous substrates. Several non‐mutually exclusive visual signalling hypotheses can be proposed to explain this phenomenon. Coloration could be used to signal: (1) dominance towards conspecifics, with darker birds being dominant (status signalling hypothesis); (2) sex (gender signalling hypothesis) because females are usually more intensely coloured; (3) individual quality for mate choice (quality signalling hypothesis); or (4) different reproductive strategies between individuals (e.g. in polyandrous trios). Here we report results from systematic monitoring of breeding Bearded Vultures in the pre‐laying period in the central and western Pyrenees (Spain and France) between 2016 and 2020, including 162 individuals from 70 reproductive units (48 pairs and 22 trios). We classified individuals as being white, pale, medium or dark, and analysed the relationship with sex, mating system (pair or trios) and average productivity across years. Our results showed that the most common form was medium (67%), then pale (22%), dark (9%) and white (2%) morphs. Overall, females were darker than males, but with a large overlap in coloration. In trios, dominant males were darker than subordinate males, although differences were not statistically significant. The mating system (pair or trio) did not influence female coloration. A multimodel comparison showed that the number of years of territory occupation, mating system and their combination (but not coloration) were the best predictors of average productivity. Our results do not support the gender signalling hypothesis. The reproductive strategy signalling hypothesis might be supported because beta males were, on average, paler than males in pairs, but this topic requires further investigations because our results were inconclusive. Finally, that females (thought to be dominant because of their slightly larger size) were on average darker than males agrees with the status signalling hypothesis, although an experimental approach would be needed to formally test this hypothesis.
Framework: Financial Technology (FinTech) is an industry composed of diversified firms that combine financial services with innovative technologies. The research question and main goal are attempting ...to answer whether they are more similar to traditional banks or trendy technological firms deploying their innovativeness to favor financial inclusion and sustainability. Justification: Evaluators may wonder if FinTechs follow the typical evaluation patterns of bank/financial intermediaries or those of technological firms. Preliminary empirical evidence shows that the latter interpretation is the one consistent with the stock-market mood. Objective: This study goes beyond the extant literature, analyzing the differences between FinTechs and traditional banks in market valuation, and showing the potential for digital interaction and cross-pollination of complementary business models. Methodology: The differences will be empirically analyzed with the stock market valuation and the multipliers associated with these firms. Results: The main contribution of this paper is that the appraisal approaches of FinTechs follow those of technological startups, having a revenue model much more scalable than that of a typical bank. FinTechs may so provide a solution for sustainable finance with microfinance and crowdfunding among others. FinTechs and traditional banks may eventually converge towards a common market exploiting co-opetition strategies.
Abstract In eastern Spain, Bonelli's eagle ( Aquila fasciata ) abundance has declined almost 50% in the last 25 years and, consequently, the species is listed as regionally endangered. Therefore, the ...aim of this study is to report the mortality causes of territorial breeding Bonelli's eagles, including the spatial and temporal patterns, and to assess the effects on population dynamics. From 2015–2023, we tracked 60 Bonelli's eagles via global positioning system‐global system for mobile communications (GPS‐GSM) telemetry; 33 of the eagles died (median survival time = 1,519 days). Survival did not differ in relation to sex, age at capture (subadult vs. adult birds), breeding site (coastland vs. inland territories), or transmitter's model. One‐year probability of survival (95% CI) was 0.716 (0.607–0.845); 2‐year survival was 0.640 (0.524–0.781); and 3‐year survival was 0.581 (0.464–0.729). Anthropogenic mortality (66.7% of cases) prevailed over natural (27.3%) and unknown causes (6.0%). Causes of mortality were intra‐ and interspecific predation (24.2% of cases), electrocution (18.2%), poisoning (15.1%), collision with power lines (9.1%), shooting (9.1%), drowning (9.1%), collision with other man‐made infrastructure (6.1%), and disease (3.0%). Deaths were most frequent during the early breeding season. Only 2 (6.1%) of 33 deaths recorded occurred within a protected area. Natural causes of mortality were more frequent away from the Mediterranean coast. In contrast, anthropogenic deaths were more frequent near the Mediterranean coast, where human population density is high. We estimated that probability of extirpation of the species in our study area is 17.8% in the next 50 years and 99.2% in 100 years. Nonetheless, a small reduction in adult mortality by ≥15% could prevent extirpation in the next 50 years. Therefore, actions to reduce adult mortality are urgently needed to preserve the Bonelli's eagle in eastern Spain.
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.
Adjustment of reproductive timing within the annual cycle is a crucial issue for both offspring and parents’ survival, and breeding success. Early laying date is closely related to successful ...breeding outcome and better survival. Obtaining long datasets on threatened long-lived species’ breeding performance can contribute to their conservation. Using field observations and telemetry information, here we analyse how laying date of an endangered long-lived raptor varies with nest characteristics, individual factors and climatic variables during an 18-year (2004–2021) study period in eastern Spain. To this end, we estimated how environmental and individual variables affect laying date. Our results showed that average laying date in our study area took place on February 17th. Laying date showed no trend during the study period. Nests placed in higher elevations showed delayed laying dates. Territories occupied by adults with previous successful experience and high brood size showed earlier laying dates. Current year laying date was highly correlated with previous year laying date. Colder territories delayed laying date and the minimum temperature of the previous December were negatively correlated to previous laying date. Our results highlight the importance of experienced birds able to adjust timing of reproduction to maximise biological fitness. High adult mortality allows sub-adults to settle as breeders and jeopardises species’ persistence. Therefore, the reduction of mortality of territorial birds is of the outmost importance to improve the conservation status of declining long-lived species such as the Bonelli’s eagle (
Aquila fasciata
).
In this paper, we show how many fixes are enough to define the territory of two long-lived resident raptors marked by GPS transmitters. To this end, we analyzed high-resolution GPS data from 50 ...territorial Bonelli’s eagles (
Aquila fasciata
) and 9 territorial Golden eagles (
Aquila chrysaetos
) equipped with GPS/GSM dataloggers. Our results show that between 2200 and 2800 fixes are enough to define the territory. This is interesting for movement ecology works where long-term GPS data series are not available.
Predation is one of the main causes of adult mortality and breeding failure for ground-nesting birds. Micro-habitat structure around nests plays a critical role in minimizing predation risk. Plovers ...nest in sites with little vegetation cover to maximize the incubating adult visibility, but many studies suggest a trade-off between nest-crypsis and predator detection strategies. However, this trade-off has not been explored in detail because methods used so far do not allow estimating the visibility with regards to critical factors such as slope or plant permeability to vision. Here, we tested the hypothesis that Kentish plovers select exposed sites according to a predator detection strategy, and the hypothesis that more concealed nests survive longer according to a crypsis strategy. To this end, we obtained an accurate estimation of the incubating adult's field of vision through a custom built inverted periscope. Our results showed that plovers selected nest sites with higher visibility than control points randomly selected with regards to humans and dogs, although nests located in sites with higher vegetation cover survived longer. In addition, the flushing distance (i.e., the distance at which incubating adults leave the nest when they detect a potential predator) decreased with vegetation cover. Consequently, the advantages of concealing the nest were limited by the ability to detect predators, thus indirectly supporting the existence of the trade-off between crypsis and predator detection. Finally, human disturbance also constrained nest choice, forcing plovers to move to inland sites that were less suitable because of higher vegetation cover, and modulated flushing behavior, since plovers that were habituated to humans left their nests closer to potential predators. This constraint on the width of suitable breeding habitat is particularly relevant for the conservation of Kentish Plover in sand beaches, especially under the current context of coastal regression and increase of recreational activities.
Man-induced mortality of birds caused by electrocution with poorly-designed pylons and power lines has been reported to be an important mortality factor that could become a major cause of population ...decline of one of the world rarest raptors, the Spanish imperial eagle (Aquila adalberti). Consequently it has resulted in an increasing awareness of this problem amongst land managers and the public at large, as well as increased research into the distribution of electrocution events and likely mitigation measures.
We provide information of how mitigation measures implemented on a regional level under the conservation program of the Spanish imperial eagle have resulted in a positive shift of demographic trends in Spain. A 35 years temporal data set (1974-2009) on mortality of Spanish imperial eagle was recorded, including population censuses, and data on electrocution and non-electrocution of birds. Additional information was obtained from 32 radio-tracked young eagles and specific field surveys. Data were divided into two periods, before and after the approval of a regional regulation of power line design in 1990 which established mandatory rules aimed at minimizing or eliminating the negative impacts of power lines facilities on avian populations. Our results show how population size and the average annual percentage of population change have increased between the two periods, whereas the number of electricuted birds has been reduced in spite of the continuous growing of the wiring network.
Our results demonstrate that solving bird electrocution is an affordable problem if political interest is shown and financial investment is made. The combination of an adequate spatial planning with a sustainable development of human infrastructures will contribute positively to the conservation of the Spanish imperial eagle and may underpin population growth and range expansion, with positive side effects on other endangered species.
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