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1.
Animals (Basel) ; 13(12)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37370424

RESUMO

In an ongoing study of the striped hyena (Hyaena hyaena), we observed that in the nine different females, alloparenting by the daughters of a previous litter was not uncommon and occurred on fifteen different occasions, twice with two helpers. Alloparenting persisted from when the cubs are approximately a month old until they reach the age when they go out foraging with their mothers at 10-12 months. Helpers perform most maternal duties, except suckling, even in the mother's presence. Helpers accrued indirect fitness and practiced parenting before reaching sexual maturity. Future studies must study the reproductive biology of the striped hyena in the wild throughout its geographic range to elucidate additional breeding properties that have not yet been identified. The continued persecution of striped hyenas and the lack of information about their breeding rituals and capabilities in the wild mean that this study of their different reproduction strategies, focusing on surrogate mothers, is of great conservation importance. The fact that we have found cooperative breeding in this solitary species suggests that there is much more to uncover of the enigmatic striped hyena in the wild.

2.
Sci Rep ; 13(1): 3982, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894580

RESUMO

The striped hyena (Hyaena hyaena) is considered "Near Threatened" globally and "Vulnerable" in the Middle East. In Israel, the species has experienced extreme population fluctuations owing to poisoning campaigns during the British Mandate (1918-1948) which were also further exacerbated by the Israeli authorities in the mid-twentieth century. We collated data from the archives of the Israel Nature and Parks Authority for the past 47 years to elucidate the temporal and geographic trends of this species. During this period we found a 68% increase in population and the estimated density is at present 2.1 individuals/100km2. This is significantly higher than all previous estimates for Israel. It appears that the major factors contributing to their phenomenal increase in number are the increase in prey availability because of the intensification of human development, preying on Bedouin livestock, the extinction of the leopard (Panthera pardus nimr), and the hunting of wild boars (Sus scorfa) and other agricultural pests in some parts of the country. Reasons should also be sought in increasing people's awareness as well as in advanced technological capabilities that have allowed an improved observation and reporting system. Future studies need to understand the effects of the large concentrations of striped hyenas on the spatial distribution and temporal activity of other sympatric wildlife to ensure the continued persistence of the wildlife guilds in the Israeli nature.


Assuntos
Hyaenidae , Panthera , Animais , Humanos , Israel , Agricultura , Oriente Médio
3.
PLoS One ; 17(7): e0266129, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35802713

RESUMO

The earth's geomagnetic field (GMF) is known to influence the behaviour of a wide range of species, but remains one of the most enigmatic of animal senses. Animals are known to utilize the GMF for a wide range of survival capabilities such as navigation and orienteering, migration, territoriality, homing, etc. Despite a lot of study in this regard on vertebrates, little is known about the effects of GMF on felids. Hence, we analyzed the body alignment of the Indian Leopard during defecation, and walking along the trails in the Jhalana Reserve Forest in India. Using circular statistics, we found that the leopards aligned their bodies on the north-south axis during defecation (mean azimuth -176.4°), while no such preference was found when walking (mean azimuth 52.9°). Thus we prove that leopards are sensitive to the GMF during basic physiological activities and in this context show similar behaviour to other vertebrates studied to date.


Assuntos
Panthera , Animais , Florestas , Fator de Maturação da Glia , Fenômenos Magnéticos , Panthera/fisiologia , Territorialidade
4.
Animals (Basel) ; 12(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35625126

RESUMO

The diet and breeding success of Eagle Owls (Bubo bubo) have been suggested to vary at different latitudes. However, it is still unclear whether and how these relationships exist at lower latitudes outside of Europe. We therefore studied the diet and breeding success of Eagle Owls during four breeding seasons at 14 nests in the Judea region, Israel. Of a total of 9461 prey items were identified; mammals (N = 6896, 35 species; 72.89%, biomass 62.3%) and birds (N = 2255, 55 species, 23.83%; biomass 36.0%) predominated the prey-base. We found that the gradient of diversity of the mammalian prey decreased from west to east; and avian prey increased from east to west. The index of species diversity, H' for all prey, had no relationship with breeding success. The prey-base of the Eagle Owls helped identify the changes in geographic distributions of several species. Marbled polecat (Vormela peregusna), especially threatened, appear to be relatively abundant, as are brown rats (Ratttus norvegicus) which were previously considered to be restricted to the coastal regions. In addition to Egyptian fruit bats (Rousettus aegyptiacus), the Eagle Owls also preyed on nine different species of insectivorous bats, several of which appear to have enlarged their geographic distribution within Israel. The Eagle Owl's diet emphasizes its generalist foraging habits, but pairs may be species-specific specialists. This adaptation is especially important in a fast-developing and congested country like Israel, because a generalist hunting strategy probably allows the species to subsist in the region.

5.
Animals (Basel) ; 11(12)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34944314

RESUMO

Display, wherein males attempt to maximize fitness by attracting sexually mature females to mate, is known to drive speciation by Sexual Selection. We researched the Red Sea Ghost Crab (Ocypode saratan; RSGC), in which males build display pyramids to attract females. The study was conducted at the beach in Eilat, Israel. At each session, we measured the height (in cm) of all pyramids and the dimensions (height, breadth; in cm) of the burrow entrance. We assumed that the size of the entrance represented the relative size of the carapace width of the occupant. The mean (± SE) entrance volume was 230.8 ± 11.7 cm, and the height of the pyramid was 11.8 ± 0.49 cm (n = 54). The results of our study did not support our hypothesis because we had expected to find a linear correlation between body size and pyramid height, i.e., the larger the male, the larger the pyramid. However, our results show that the largest males in the population either built small pyramids or not at all, and the cut-off of the larger crab's body size appears to be around 350 cm3. We discovered a step-wise function in the data in that crabs with the smallest body size of ca. 250 cm3 constructed the highest pyramids, with a declining tendency between 250-350 cm3 and extremely low pyramids beyond 350 cm3. However, our findings need to be further studied with a stress on the ambiance and elucidate whether the habitats differ in temperature, humidity, prey-base, etc., before concluding as to why the larger males desist from building pyramids. This study underwrites the importance of studying the mating systems of the macro-fauna of the beaches that are fast disappearing owing to anthropogenic development.

6.
Biol Conserv ; 263: 109339, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34580549

RESUMO

Changes in ecosystems resulting from anthropause caused by Covid-19 relate to both abiotic and biotic factors which have both a positive or negative effect on wildlife. The lockdown was manifested by reduced air and water pollution, lower mortality of animals on the roads, an increase in animals' body condition and reproduction success. On the other hand, the closures lead to an increase in the populations of invasive species or poaching. We studied the behavioural reaction of natural, desert-dwelling Nubian ibex (Capra nubiana) on the appearance of a new element in the environment - the facial-masks. We hypothesized that the mask would trigger a response expressed through differences in the vigilance towards a potentially new threat. We applied the flight initiation distance (FID) technique to check the reaction at the approach of a human with a facial-mask and without it. The average FID was 8.8 m and was longer when the observer was wearing a mask (10.7 m) as compared to trials without the mask (6.9 m). Our study indicates that wildlife, even if habituated to human silhouette at a distance, appear to notice unusual accessories when up-close and respond by increased vigilance and what may affect their overall fitness.

7.
Sci Total Environ ; 793: 148672, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34328996

RESUMO

Actions taken against the COVID-19 pandemic have dramatically affected many aspects of human activity, giving us a unique opportunity to study how wildlife responds to the human-induced rapid environmental changes. The wearing of face masks, widely adopted to prevent pathogen transmission, represents a novel element in many parts of the world where wearing a face mask was rare before the COVID-19 outbreak. During September 2020-March 2021, we conducted large-scale multi-species field experiments to evaluate whether face mask-use in public places elicits a behavioural response in birds by comparing their escape and alert responses when approached by a researcher with or without a face mask in four European countries (Czech Republic, Finland, Hungary, and Poland) and Israel. We also tested whether these patterns differed between urban and rural sites. We employed Bayesian generalized linear mixed models (with phylogeny and site as random factors) controlling for a suite of covariates and found no association between the face mask-wear and flight initiation distance, alert distance, and fly-away distance, respectively, neither in urban nor in rural birds. However, we found that all three distances were strongly and consistently associated with habitat type and starting distance, with birds showing earlier escape and alert behaviour and longer distances fled when approached in rural than in urban habitats and from longer initial distances. Our results indicate that wearing face masks did not trigger observable changes in antipredator behaviour across the Western Palearctic birds, and our data did not support the role of habituation in explaining this pattern.


Assuntos
COVID-19 , Máscaras , Animais , Teorema de Bayes , Aves , Humanos , Pandemias , SARS-CoV-2
8.
Animals (Basel) ; 11(6)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198631

RESUMO

As is well-known, endemic island bird species are especially vulnerable to extinction from anthropogenic environmental change and reduced fitness compared with mainland taxa. The Cyprus Scops Owl, Otus cyprius, is a recently recognized island endemic species whose ecology and breeding biology have not been studied. It nests mainly in holes in trees and buildings, so the felling of old trees, modern architectural practices, and the renovation of old houses in villages may reduce nest site availability. Its population trend is also unknown. Therefore, to better determine its ecological requirements and habitat preferences we placed nest boxes in rural areas adjacent to the forest, in the forest, and in the ecotone between them, and used breeding success as our indicator of habitat suitability. We found that breeding parameters like laying date, clutch size, length of the incubation period, hatching day, hatching success, and number of nestlings did not differ between the three habitats. Despite the low level of nest box occupancy rate (5-11%) the endemic Cyprus Scops Owl readily breeds in artificial nests. Therefore, although we are unaware of any current threats to the Cyprus Scops Owl, we recommend that its conservation be prioritized, including studies, monitoring, habitat conservation, and the provision of nest boxes.

9.
Animals (Basel) ; 11(1)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33430010

RESUMO

The Eurasian Black Vulture is a globally threatened raptor that in Southeast Europe only occurs in an isolated population in Greece. We examined the population viability for the species under demographic fluctuations and conservation scenarios. The current population showed no possibility of extinction for the next 100 years. However, simulated scenarios showed that the most important factor affecting the viability of the species was medium and high poisoning, leading to 94.8% and 100% probability of extinction, respectively. Furthermore, high reduction of supplementary feeding highlighted an 18.6% extinction possibility. Also, a high increase of wind farms in the area may result in 17.4% extinction possibility. Additionally, the non-establishment of the feeding station in 1987 in the study area would have resulted in an extinction risk of 7%. The species can be translocated to the Olympus National Park by releasing 80 juveniles over 10 years. The implementation of the conservation scenarios concerning the establishment of a supplementary feeding site network, and the reintroduction of the Eurasian Black Vulture in its historic range, along with the elimination of threats posed by poisoning, low food availability, and wind farms would increase the probability of the species persistence and allow the population to become a source for dispersal across Southeast Europe.

10.
Animals (Basel) ; 10(9)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911836

RESUMO

The suitability of the camera trap-retrap method was explored for identifying territories and studying the spatial distribution of leopards (Panthera pardus fusca) in the Jhalana Reserve Forest, Jaipur, India. Data from two years (November 2017 to November 2019, N = 23,208 trap-hours) were used to provide estimates of minimum home-range size and overlap. We conducted home-range analysis and estimation, using the minimum convex polygon (MCP) method with geographic information system (GIS) tools. We are aware of the limitations and advantages of camera trapping for long-term monitoring. However, the limitations of the research permit allowed only the use of camera traps to estimate the home ranges. A total of 25 leopards were identified (male = 8, female = 17). No territorial exclusivity was observed in either of the sexes. However, for seven females, we observed familial home-range overlaps wherein daughters established home ranges adjacent to or overlapping their natal areas. The median home range, as calculated from the MCP, was 305.9 ha for males and 170.3 ha for females. The median percentage overlap between males was 10.33%, while that between females was 3.97%. We concluded that camera trapping is an effective technique to map the territories of leopards, to document inter- and intraspecific behaviors, and to elucidate how familial relationships affect dispersal.

11.
Ecology ; 100(11): e02846, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31350852
12.
J Environ Manage ; 237: 1-4, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30776769

RESUMO

We studied the effect of tourist activity on the reproductive success of sergeant major damselfish (Abudefduf saxatilis). We snorkeled at two sites - one with a bridge over the reef allowing access to the reef from the seaside (Princess beach) and further south where the number of tourists is low (Taba beach). We identified 36 (65.5%) nests on the Princess reef and 19 (34.5%) on the Taba reefs. Average nest size at Princess was 11.8 cm2 (±2.68 SD) vs 19.6 cm2 (±3.9) at Taba. Further, at Princess although the number of nests was not correlated to the distance from the bridge (R2 = 0.352), average nest size increased with distance from the bridge (R2 = 0.861). At Taba, nests on the continuous reef averaged 21.8 cm2 (±1.8, N = 13) while those on the loose aggregation reefs averaged 14.8 cm2 (±2.02, N = 6). Although reef tourism is increasingly being regarded a major source to generate income for human coastal communities, a better understanding of the consequences of human activities to the reef system can enhance conservation initiatives and facilitate management implementation.


Assuntos
Cruzamento , Meio Ambiente , Humanos
13.
Behav Processes ; 158: 113-116, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30465887

RESUMO

Asymmetries in handedness/footedness has been demonstrated in many vertebrate and invertebrate species, including humans, but its role and origins are still debated. We studied the ratio of footedness in migratory Steppe Buzzards (Buteo vulpinus). We hypothesized that during our raptor banding program we could observe the preferred foot used by the raptor when trying to access the lure in a bal-chatri trap, and that if there was no preference in the population then it would show a 50:50 use of the right or left foot. A total of 367 different Steppe Buzzards were identified and their footedness analyzed. Of these 196 (53.4%) preferentially hit the trap first with the right foot, 148 (40.3%) with the left foot, and 23 (6.3%) appeared to be ambidextrous. In the avian world, predominance is considered to be species specific but mostly right-footed. The migratory Steppe Buzzards also show a predominantly right-sided lateralization. This result could be due to the task/situation that was analyzed; perhaps in a different more tool-like manipulation activity lateralization could be different. We recommend all future researchers that deal in wildlife trapping to also pay attention to this very interesting aspect of wildlife biology.


Assuntos
Pé/fisiologia , Lateralidade Funcional/fisiologia , Falcões/fisiologia , Animais , Feminino , Masculino , Especificidade da Espécie
14.
Sci Rep ; 8(1): 13989, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30228370

RESUMO

Life-history theory predicts that current behaviour affects future reproduction, implying that animals should optimise their escape strategies to reflect fitness costs and benefits of premature escape. Both costs and benefits of escape may change temporally with important consequences for the evolution of escape strategies. Moreover, escape strategies of species may differ according to their positions on slow-fast pace of life gradients. We studied risk-taking in long-distance migratory animals, waders (Charadriiformes), during the annual cycle, i.e., breeding in Europe, stopover in the Middle East and wintering in tropical Africa. Phylogenetically informed comparative analyses revealed that risk-taking (measured as flight initiation distance, FID) changed significantly over the year, being lowest during breeding and peaking at stopover sites. Similarly, relationships between risk-taking and life-history traits changed among stages of the annual cycle. While risk-taking significantly decreased with increasing body mass during breeding, risk-taking-body mass relationship became marginally significant in winter and disappeared during migration. The positive trend of risk-taking along slow-fast pace of life gradient measured as adult survival was only found during breeding. The season-dependent relationships between risk-taking and life history traits suggest that migrating animals respond to fluctuating environments by adopting behavioural plasticity.


Assuntos
Migração Animal/fisiologia , Aves/fisiologia , Reprodução , Estações do Ano , Animais , Cruzamento , Características de História de Vida , Assunção de Riscos
15.
Environ Sci Pollut Res Int ; 24(33): 25986-26005, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28942505

RESUMO

This study examines the potential to use instrumental neutron activation analysis (INAA) to explore temporal and geographical variation in exposure to heavy metals and other selected elements in common kestrel Falco tinnunculus using feathers from a natural history collection. The study gathered samples of two breast feathers from each of 16 adult male kestrel specimens from Naturalis Biodiversity Centre, collected in The Netherlands between 1901 and 2001. Feather samples were analysed for more than 50 elements, using INAA at the Reactor Institute Delft. Results (in mg/kg dw) were transformed into ratios of milligram of element per millimetre of feather length. The distribution of the mass fractions and ratios was plotted for each element against time and by geographical area. Observed mass fractions and/or ratios are discussed for selected elements (Hg, Cd, Zn, Pt, Pd, Se, Al, Rb, As, Sb, Cr, V, Cl, Br) known to have, at certain concentrations, adverse effects on raptors. Some samples show mass fractions of certain elements (Cr, Cd, Se, As) above levels known to have adverse effects. We conclude that the analysis of museum feathers using INAA provides reference values for concentrations of selected elements, including those of high societal concern such as Hg and Cd, against which to assess concentrations of these elements in feathers of present-day living raptor populations.


Assuntos
Monitoramento Ambiental , Falconiformes , Plumas/química , Mercúrio/análise , Análise de Ativação de Nêutrons , Animais , Poluentes Ambientais/análise , Masculino , Metais Pesados/análise , Museus , Países Baixos , Estudos Retrospectivos
16.
PeerJ ; 5: e3288, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28584699

RESUMO

The number of species that specialize in pre-dispersal seed predation is relatively small. Examples of specialized pre-dispersal seed predators adapted to feeding on closed cones include vertebrate species like Crossbills, Squirrels, Nutcrackers and Woodpeckers. Seed predation selects against certain phenotypic features of cones and favors another phenotypic features. In this study, we document preferences of the Great Spotted Woodpecker (Dendrocopos major) for specific traits in the cones of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris). We found that the Great Spotted Woodpecker prefers to feed on medium sized Norway spruce cones. The results suggest a disruptive selection that favors the extreme cone lengths in Norway spruce. In Scots pine, the woodpeckers avoided cones with large apophyses. Further, the selectivity for the specific characteristics of the cones is probably related to the configuration of the anvil, a place at which woodpeckers extract seeds from the cones. We think that the Great Spotted Woodpecker preferences in relation to the morphological characteristics of cones are a key to the design of the anvil in order to maximize the use of it as a tool for processing cones of both the Norway spruce and the Scots pine.

17.
Naturwissenschaften ; 104(5-6): 48, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28540595

RESUMO

Fascination with animals and their behaviour is one the most prominent patterns persisting in all human cultures. During the last decades, however, technological development and public access to the Internet have increased the speed and the extent of information sharing at an unprecedented rate, in some cases even challenging the traditional methods used in science. In order to understand the extent of this influence, we focused on the behaviour of shrikes. Shrikes are an enigmatic group of songbirds with a unique behaviour of impaling prey. We employed an extensive Internet search on YouTube (YT), a very popular and increasingly important source of information worldwide, for videos recording shrikes. Our analyses revealed that the number of shrike videos on YT is strongly positively correlated with classical knowledge on shrikes from books and scientific articles. Our results also suggest that in some cases YT may provide an alternative source of information on shrike ecology and behaviour. YT videos may thus provide new insights into the study of certain species or subjects and help identify gaps in ecological studies, especially in poorly studied species.


Assuntos
Comportamento Animal/fisiologia , Internet , Passeriformes/fisiologia , Pesquisa/tendências , Mídias Sociais/tendências , Animais , Pesquisa/normas , Mídias Sociais/normas , Gravação em Vídeo/estatística & dados numéricos , Gravação em Vídeo/tendências
18.
PeerJ ; 4: e2070, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27441105

RESUMO

The reaction of wildlife to humans is known to differ with surroundings. In urban environments that provide suitable habitats for breeding birds, animals adapt to humans and their response is accordingly altered. This study examined the nest defense behavior of female Eurasian sparrowhawks (Accipiter nisus) during the breeding season in urban and rural areas of Prague. The females showed four different types of reaction to humans that approached the nest and differed significantly between the two study areas. Contrary to expectations, urban nesting females were more aggressive than rural conspecifics. The intensity of response increased as the season progressed, and females defended their broods to a much greater degree than their clutches in both urban and rural habitats, suggesting a differential effort as a function of their relative investment in the breeding attempt conforming with the parental investment hypothesis.

19.
Acta Ethol ; 19: 91-94, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26843781

RESUMO

The hooded crow Corvus cornix is a west Palaearctic, solitary nesting, monogamous corvid. In the breeding season, populations are characterized by a social organization wherein breeding pairs are territorial and non-breeding individuals, called floaters, live in flocks. During a study of the breeding ecology of the hooded crow, conducted in a protected flooded area, we monitored nests with video cameras. We recorded two separate incidents when intruders attacked a female at the nest. We believe that she remained in the nest in order to prevent the strangers cannibalizing the nestlings by mantling over the brood. The spatio-temporal occurrence of these attacks suggests that the observed behaviour is intraspecific sexual aggression wherein non-breeding males mounted an immobilized female.

20.
Zookeys ; (530): 113-27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26692801

RESUMO

The Mediterranean Sea is known as an ecological barrier for numerous migratory birds flying from European breeding grounds to African wintering sites. Birds generally avoid migration over open sea and fly over land. In the Mediterranean Basin, few land bridges or bottlenecks for migratory birds exist. The narrowest are at the western and eastern extremes: the Strait of Gibraltar and Israel. Comparative studies between these locations are extremely rare to date. Therefore, in order to elucidate the differences between the two flyways, we compared data collected simultaneously for two sister leaf warbler species, the Bonelli's Warbler complex, Phylloscopus bonelli and Phylloscopus orientalis, at ringing stations in the western Mediterranean Basin Gibraltar, and the eastern Eilat, Israel. Data on biometrics and passage dates of individuals trapped at Gibraltar and Eilat were used, and it was found that mean arrival date of Western Bonelli's Warblers at Gibraltar was 15 days later than Eastern Bonelli's Warblers at Eilat. Furthermore, Western Bonelli's Warblers had shorter wings than Eastern Bonelli's Warblers. On the other hand, birds in Eilat were in poorer body condition than individuals in Gibraltar. The comparison between geographically distant stop-over sites contributes to furthering our understanding of the development of migration strategies across ecological barriers in sibling species. Our study showed that populations that breed in southwestern Europe migrate through Gibraltar and winter in West Africa are able to accomplish migration in comparatively good body condition. This is in contrast to those that winter in East Africa, migrate through Israel and have to endure the combined challenge of crossing the Sahel, Sahara and Sinai deserts before reaching their breeding grounds across southeast Europe and southwest Asia. Hence, the discrepancies described between the western and the eastern flyway suggest that individuals in the west, in general, migrate shorter distances, have a physiologically less demanding crossing of the North African deserts and appear to stage before their crossing the Strait of Gibraltar, a privilege unavailable to the migrants of the eastern flyway.

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