Lepus Europaeus Research Articles

European Brown Hare Syndrome in Poland: Current Epidemiological Situation.

European brown hare syndrome (EBHS) is one of the main causes of mortality in brown hares (Lepus europaeus) and mountain hares (Lepus timidus) in Europe. Since the mid-1990s, this highly lethal and contagious plague has been widespread in many European countries, contributing to a drastic decline in the number of free-living and farmed hares. A second lagovirus, able to infect some species of hares is rabbit haemorrhagic disease virus 2 (RHDV2; GI.2) recognised in 2010, a new viral emergence of RHDV (GI.1) which is known to be responsible for haemorrhagic disease in rabbits-RHD. The aim of this study was to evaluate the current EBHS epidemiological situation on the basis of the presence of antibodies to European brown hare syndrome virus (EBHSV) and anti-RHDV2 antibodies in sera collected from free-ranging hares in Central and Southeastern Poland in 2020-2021. Additionally, studies on the presence of EBHSV and RHDV2 antigens or their genetic material in the blood and internal organs taken from brown hares between 2014 - 2021 have been carried out. The results of the serological examination showed nearly 88% of tested blood samples were positive for EBHSV antibodies. No EBHSV was identified in the examined hares using virological and molecular tests. The positive results of EBHS serological studies confirmed the circulation and maintenance of EBHSV in free-living brown hares in Poland. However, no serological, virological or molecular evidence was obtained indicating that the brown hares tested had been in contact with RHDV2.

Absence of anti-Besnoitia spp. specific antibodies in European wild lagomorphs from the Iberian Peninsula.

Besnoitia besnoiti is an apicomplexan parasite whose life cycle is not completely understood. It is assumed that this parasite might have an indirect life cycle with a carnivore as a definitive host able to shed oocysts after the ingestion of mature cysts in tissues of an infected intermediate host. Cattle and wild cervids on the Iberian Peninsula can act as intermediate hosts of B. besnoiti, and exposure to the parasite has been demonstrated in equids. In this study, we aimed to assess the presence of members of the genera Besnoitia in wild lagomorphs from the Iberian Peninsula and the potential role of these host species in the life cycle of B. besnoiti, as all the animals were sampled from 19 regions of the Iberian Peninsula where cases of bovine besnoitiosis have been previously detected. Serum samples (Oryctolagus cuniculus: n = 552; Lepus europaeus: n = 122) were first analysed by ELISA and subsequently confirmed by Western blot (WB). Specific antibodies against B. besnoiti were not found in any sampled animal by WB. In addition, lung samples from a subset of wild rabbits (n = 16) were tested by PCR and Besnoitia spp. DNA was not detected. These results suggest that Besnoitia spp. are unlikely to circulate in wild lagomorphs in the Iberian Peninsula. Thus, lagomorphs are not expected to play a key role in the biological cycle of B. besnoiti. Further studies are necessary to assess whether different micromammal species, such as rodents, can serve as natural reservoirs of Besnoitia spp. in other European regions.

Bidirectional hybridisation and introgression between introduced European brown hare, Lepus europaeus and the endemic Irish hare, L. timidus hibernicus

Introduced non-native species can threaten native species through interspecific hybridisation and genetic introgression. We assessed the prevalence of hybridisation and introgression between introduced European brown hare, Lepus europaeus, and the endemic Irish hare, L. timidus hibernicus. Roadkill hares (n = 56) were sequenced for a 379bp section of the mitochondrial DNA D-loop and a 474bp segment of the nuclear transferrin (Tf) gene. A species-specific indel in the transferrin gene was present in L.t. hibernicus and absent in L. europaeus. Excluding three hares from which molecular data could not be recovered, 28 hares (53%) were native L.t. hibernicus, 7 (13%) were non-native L. europaeus and 18 (34%) were hybrids; of which 5 (28%) were first generation (F1) involving bidirectional crosses with mismatched nuclear and mtDNA (3 ♂ europaeus x ♀ hibernicus and 2 ♂ hibernicus x ♀ europaeus). Mixed nuclear transferrin sequences suggested 13 (72%) of hybrids were at least 2nd generation (F2) with 9 (69%) possessing L.t. hibernicus and 4 (31%) L. europaeus mtDNA (the latter indicative of hybrid backcrossing with the non-native). The prevalence of hybridisation at similar mountain-brown hare contact zones throughout Europe is notably lower (4–16%) and typically unidirectional (♂ europaeus x ♀ timidus). A high prevalence of bidirectional hybridisation and introgression (in association with projected climate change) may favour the introduced species over the native. Genetic surveillance and population monitoring are needed to further explore the potential conservation implications of European brown hare in Ireland.

European Hares, Lepus europaeus, Represent a Reservoir Host for Thelazia callipaeda in Romania.

Thelaziosis caused by Thelazia callipaeda is an emerging disease in Europe. Only two reports of naturally infected lagomorphs have been published so far. The aim of this study was to evaluate the status of the Romanian populations of European brown hares, Lepus europaeus as reservoir hosts for T. callipaeda. Between November 2019 and November 2021, the eyes of 326 L. europaeus carcasses were examined for the presence of ocular parasites. Nematodes were stored in plastic vials with physiological saline, followed by morphological and molecular identification. QGis 3.20 and EpiInfoTM 7 were used for mapping and statistical analysis. Four (1.23%) hares harbored T. callipaeda infection, with a total of 84 nematodes collected (mean intensity 21 nematodes/host), with 45 males, 39 females (two sexually immature, seven with only eggs, and 30 with eggs and larvae). One specimen from each host was successfully sequenced resulting in a 100% similarity with several other sequences of T. callipaeda haplotype 1. Statistical analysis revealed no significant results. The current study represents a first report of T. callipaeda in the European brown hare in Romania, and the second in Europe, also reiterating the role of lagomorphs as reservoir hosts for this zoonotic ocular nematode.

Eating in an extreme environment: diet of the European hare (Lepus europaeus) on Vesuvius

The European hare (Lepus europaeus) is cosmopolitan species, living in a variety of habitats and showing a diversified diet, that has been described mainly from agricultural meadows and crops, with little information available for extreme environments. Here, we describe, for the first time, the diet of the European hare from Mount Vesuvius, using DNA metabarcoding and high-throughput sequencing on DNA extracted from faecal pellets, a proxy for a population living in a volcanic environment. The DNA from pellets was first genetically assigned to European hare using high-resolution melting analysis. The diet of the hare on Vesuvius is mainly composed of herbaceous species belonging to Fabaceae (86.26% of total diet). The most frequent plant items ingested by the species are Galega officinalis and Lupinus angustifolius (67.10% of total diet), although these are detected only sporadically in the study area. Indeed, the spectrum of available plants also includes other easily accessible wild (i.e. Lolium sp., Bromus sp., Rumex sp.) and cultivated (i.e. Solanum lycopersicum, Cucumis melo, Pisum sativum) plant items, found only in traces in the diet of the hares. Our contribution adds information on the trophic ecology of the European hare, exploring its ability to live in an extreme environment. This could be useful to set a management strategy for conservation of the species, which is ecologically relevant on Vesuvius as prey for birds and mammals, as well as a vegetation modulator via selective grazing by endozoochory. Furthermore, our study represents the latest information on the diet of the hare living in an environment that no longer exists: an extensive fire destroyed about 80% of the woody area after our sampling. The post-fire regrowth is transforming the original environment and consequently the trophic availability for the European hare.

Maize monoculture causes niacin deficiency in free-living European brown hares and impairs local population development

Maize (Zea mays) is the most produced crop worldwide and the second most important bio-energy plant. Huge maize monoculture is considered a threat to biodiversity in agricultural landscapes and may also contribute to the decline of European brown hares (Lepus europaeus, Pallas 1778). Indeed, the intensification of agriculture has been identified as one of the main factors responsible for the decline of brown hare populations. A reason why large maize cultures can be particularly detrimental to animals consuming this plant is its poor nutritional value with respect to niacin. In this study, we investigated the effects of the proportion of area under maize crops on liver concentrations of niacin in free-living hares, on the reproductive output of does (females), and on the development of local populations, at nine study sites in Lower Austria. Hare numbers were estimated from spotlight counts in spring and autumn. Liver samples and uteri were obtained from hares shot in the same areas during regular autumn hunts. Number of offspring born to an individual female during the preceding reproductive period was determined by counting placental scars. Our results show a significant negative effect of the area under maize crops on liver concentrations of niacin of does and on their reproductive output. Further, we found a significant negative effect of the area under maize on the development of a population. Altogether, our findings indicate that high proportions of the area under maize crops contribute to the decline of brown hares by reduced fecundity of does and impaired development of local populations.

Orthoptera in the early stages of post-arable rewilding in south-east England

The ideal aim of rewilding is to restore natural processes to create ‘self-willed’ ecosystems involving the creation of large areas of habitat subject to stochastic disturbance, connected by favorable corridors for species to disperse along. Reversion of arable farmland to grassland and scrub habitats on Black Bourn Valley nature reserve in Suffolk (south-east England) through non-intervention allowed succession to occur largely unmanaged. Fields in the early stages of rewilding (4–14 years) are found at Black Bourn Valley, while pond creation has been extensive since 2010, creating water edge habitat and heterogeneity to the re-establishing grassland. Monitoring of Orthoptera revealed statistical evidence that species diversity/richness and field grasshopper Chorthippus brunneus (Thunberg, 1815), meadow grasshopper Pseudochorthippus parallelus (Zetterstedt, 1821), common groundhopper Tetrix undulata (Sowerby, 1806) and slender groundhopper Tetrix subulata (Linnaeus, 1758) were in higher abundance in fields ≥8 years since arable cropping ceased compared to those 4 years post reversion. Fields ≥8 years old were probably favorable due to the presence of microhabitats for basking and egg-laying orthopterans that included ant hills, sparsely vegetated pond edge and open swards with an abundance of fine-leaved grasses (Agrostis and Festuca spp.) and a low abundance of leaf litter. Lagomorph grazing by wild brown hare Lepus europaeus and rabbit Oryctoloagus cuniculus was critical in maintaining exposed soil for Orthoptera in the older fields, while deer paths appeared to create microhabitats that may be utilized by Orthoptera. We postulate that rewilding schemes on arable farmland should use a Rewilding Max approach and avoid the frequent usage of domestic livestock, relying on wild lagomorph and ungulate grazers to maintain an open mosaic habitat structure with only intermittent cattle, horse, or sheep grazing.

Helminth biocoenosis of Lepus europaeus meridiei (Hilzheimer, 1906) from Pianosa island, Italy.

Pianosa is a 10 km2 Italian island in the Tyrrhenian Sea which is part of the Tuscan Archipelago National Park. In this island lives a brown hare population which, according to the literature, belongs to the ancestral taxon Lepus europaeus meridei that offers a unique opportunity to observe how the parasite biocoenosis shapes in condition of isolation, limited space availability and high population density. The aim of this work is to describe the helminth component community of a non-managed, isolated, and dense hare population, evaluating host-parasite relationship and parasite community structure. All 26 analyzed hares (13 males and 13 females) were in good physical conditions, and all of them harboured exclusively the nematode Protostrongylus oryctolagi only. This is the first report of this lungworm species in Italy. The estimated overall abundance was 48.15 worms per examined hare (range 3–258, median 50) and the parasites were unevenly distributed across host population, with few hosts having most parasites (aggregated or overdispersed distribution). No significant relationship was detected between the number of isolated parasites and hare sex and weigh. The effect of the isolation of Pianosa's hare population seems to have acted reducing parasite richness, while the high host density is probably the cause of the high prevalence and abundance of the single helminth species collected.In conclusion, despite the low impact of parasites confirmed also by the overdispersed parasite distribution, the low diversity of the studied parasite community sounds a warning for the management of the hare population and the whole Pianosa's ecosystem.

Predicting habitat suitability for Ixodesricinus and Ixodespersulcatus ticks in Finland

BackgroundTicks are responsible for transmitting several notable pathogens worldwide. Finland lies in a zone where two human-biting tick species co-occur: Ixodesricinus and Ixodespersulcatus. Tick densities have increased in boreal regions worldwide during past decades, and tick-borne pathogens have been identified as one of the major threats to public health in the face of climate change.MethodsWe used species distribution modelling techniques to predict the distributions of I.ricinus and I.persulcatus, using aggregated historical data from 2014 to 2020 and new tick occurrence data from 2021. By aiming to fill the gaps in tick occurrence data, we created a new sampling strategy across Finland. We also screened for tick-borne encephalitis virus (TBEV) and Borrelia from the newly collected ticks. Climate, land use and vegetation data, and population densities of the tick hosts were used in various combinations on four data sets to estimate tick species’ distributions across mainland Finland with a 1-km resolution.ResultsIn the 2021 survey, 89 new locations were sampled of which 25 new presences and 63 absences were found for I.ricinus and one new presence and 88 absences for I.persulcatus. A total of 502 ticks were collected and analysed; no ticks were positive for TBEV, while 56 (47%) of the 120 pools, including adult, nymph, and larva pools, were positive for Borrelia (minimum infection rate 11.2%, respectively). Our prediction results demonstrate that two combined predictor data sets based on ensemble mean models yielded the highest predictive accuracy for both I.ricinus (AUC = 0.91, 0.94) and I.persulcatus (AUC = 0.93, 0.96). The suitable habitats for I.ricinus were determined by higher relative humidity, air temperature, precipitation sum, and middle-infrared reflectance levels and higher densities of white-tailed deer, European hare, and red fox. For I.persulcatus, locations with greater precipitation and air temperature and higher white-tailed deer, roe deer, and mountain hare densities were associated with higher occurrence probabilities. Suitable habitats for I.ricinus ranged from southern Finland up to Central Ostrobothnia and North Karelia, excluding areas in Ostrobothnia and Pirkanmaa. For I.persulcatus, suitable areas were located along the western coast from Ostrobothnia to southern Lapland, in North Karelia, North Savo, Kainuu, and areas in Pirkanmaa and Päijät-Häme.ConclusionsThis is the first study conducted in Finland that estimates potential tick species distributions using environmental and host data. Our results can be utilized in vector control strategies, as supporting material in recommendations issued by public health authorities, and as predictor data for modelling the risk for tick-borne diseases.

Personality drives activity and space use in a mammalian herbivore

BackgroundAnimal personality has emerged as a key concept in behavioral ecology. While many studies have demonstrated the influence of personality traits on behavioral patterns, its quantification, especially in wild animal populations, remains a challenge. Only a few studies have established a link between personality and recurring movements within home ranges, although these small-scale movements are of key importance for identifying ecological interactions and forming individual niches. In this regard, differences in space use among individuals might reflect different exploration styles between behavioral types along the shy-bold continuum.MethodsWe assessed among-individual differences in behavior in the European hare (Lepus europaeus), a characteristic mammalian herbivore in agricultural landscapes using a standardized box emergence test for captive and wild hares. We determined an individuals’ degree of boldness by measuring the latencies of behavioral responses in repeated emergence tests in captivity. During capture events of wild hares, we conducted a single emergence test and recorded behavioral responses proven to be stable over time in captive hares. Applying repeated novel environment tests in a near-natural enclosure, we further quantified aspects of exploration and activity in captive hares. Finally, we investigated whether and how this among-individual behavioral variation is related to general activity and space use in a wild hare population. Wild and captive hares were treated similarly and GPS-collared with internal accelerometers prior to release to the wild or the outdoor enclosure, respectively. General activity was quantified as overall dynamic body acceleration (ODBA) obtained from accelerometers. Finally, we tested whether boldness explained variation in (i) ODBA in both settings and (ii) variation in home ranges and core areas across different time scales of GPS-collared hares in a wild population.ResultsWe found three behavioral responses to be consistent over time in captive hares. ODBA was positively related to boldness (i.e., short latencies to make first contact with the new environment) in both captive and wild hares. Space use in wild hares also varied with boldness, with shy individuals having smaller core areas and larger home ranges than bold conspecifics (yet in some of the parameter space, this association was just marginally significant).ConclusionsAgainst our prediction, shy individuals occupied relatively large home ranges but with small core areas. We suggest that this space use pattern is due to them avoiding risky, and energy-demanding competition for valuable resources. Carefully validated, activity measurements (ODBA) from accelerometers provide a valuable tool to quantify aspects of animal personality along the shy-bold continuum remotely. Without directly observing—and possibly disturbing—focal individuals, this approach allows measuring variability in animal personality, especially in species that are difficult to assess with experiments. Considering that accelerometers are often already built into GPS units, we recommend activating them at least during the initial days of tracking to estimate individual variation in general activity and, if possible, match them with a simple novelty experiment. Furthermore, information on individual behavioral types will help to facilitate mechanistic understanding of processes that drive spatial and ecological dynamics in heterogeneous landscapes.

Mammal responses to predator scents across multiple study areas

AbstractAntipredator behaviors allow prey to mitigate the impacts of their predators. We investigated antipredator responses of two herbivore species, roe deer and European hare, and one mesopredator, red fox, toward predation risk imposed by lynx and wolf. We collected data (using camera traps) on visitation frequency and vigilance behavior to olfactory predator stimuli during 158 standardized scent trials in five areas across Europe, where lynx and wolves either occurred or had been absent for centuries. After a period without scent, trial sites were either marked with lynx or wolf urine, or butyric acid (unspecific scent used to contrast species‐specific scent responses). We expected the two herbivores to respond aversively (reduced visitation frequency, and increased vigilance) to predator urine, while red foxes (scavengers) might adopt a risk‐sensitive exploration strategy by increasing vigilance near predator urine without reducing visitation frequency. For all species, we expected stronger responses toward the ambush predator lynx than to the pursue predator wolf (cryptic predator hypothesis). If prey responds more strongly to predator stimuli when coexisting with the predator, we expected stronger reactions to predator urine in areas where predators occurred (naïve prey hypothesis). Roe deer significantly avoided lynx urine and butyric acid, but not wolf urine. However, roe deer visitation frequency did not differ between scent treatment with large carnivore urine and butyric acid (suggesting that roe deer generally avoid areas with unfamiliar scent), or between areas where large carnivores were present and absent. Hares did not significantly avoid predator urine. Red foxes were attracted to lynx urine in sympatry, but not in allopatry with large carnivores. They increased vigilance rates in the presence of lynx urine independent of sympatry/allopatry with large carnivores. These findings generally confirm our expectations of predator avoidance by herbivores, and attraction combined with increased vigilance of mesopredators. In all species, lynx urine elicited stronger responses than wolf urine (although not significantly different), which to some extent conforms to the cryptic predator hypothesis. We found no support for the naïve prey hypothesis. However, higher attraction of red foxes to lynx urine in sympatric situations might indicate that positive responses by scavengers are learning based.

Potent Protease Inhibitors of Highly Pathogenic Lagoviruses: Rabbit Hemorrhagic Disease Virus and European Brown Hare Syndrome Virus.

ABSTRACTRabbit hemorrhagic disease (RHD) and European brown hare syndrome (EBHS) are highly contagious diseases caused by lagoviruses in the Caliciviridae family. These infectious diseases are associated with high mortality and a serious threat to domesticated and wild rabbits and hares, including endangered species such as riparian brush rabbits (Sylvilagus bachmani riparius). In the United States (U.S.), only isolated cases of RHD had been reported until Spring 2020. However, RHD caused by GI.2/rabbit hemorrhagic disease virus (RHDV)2/b was unexpectedly reported in April 2020 in New Mexico and has subsequently spread to several U.S. states, infecting wild rabbits and hares and making it highly likely that RHD will become endemic in the U.S. Vaccines are available for RHD; however, there is no specific treatment for this disease. Lagoviruses encode a 3C-like protease (3CLpro), which is essential for virus replication and a promising target for antiviral drug development. We have previously generated focused small-molecule libraries of 3CLpro inhibitors and demonstrated the in vitro potency and in vivo efficacy of some protease inhibitors against viruses encoding 3CLpro, including caliciviruses and coronaviruses. Here, we report the development of the enzyme and cell-based assays for the 3CLpro of GI.1c/RHDV, recombinant GI.3P-GI.2 (RHDV2/b), and GII.1/European brown hare syndrome virus (EBHSV) as well as the identification of potent lagovirus 3CLpro inhibitors, including GC376, a protease inhibitor being developed for feline infectious peritonitis. In addition, structure-activity relationship study and homology modeling of the 3CLpro and inhibitors revealed that lagovirus 3CLpro share similar structural requirements for inhibition with other calicivirus 3CLpro.IMPORTANCE Rabbit hemorrhagic disease (RHD) and European brown hare syndrome (EBHS) are viral diseases that affect lagomorphs with significant economic and ecological impacts. RHD vaccines are available, but specific antiviral treatment for these viral infections would be a valuable addition to the current control measures. Lagoviruses encode 3C-like protease (3CLpro), which is essential for virus replication and an attractive target for antiviral drug discovery. We have screened and identified potent small-molecule inhibitors that block lagovirus 3CLpro in the enzyme- and cell-based assays. Our results suggest that these compounds have the potential for further development as antiviral drugs for lagoviruses.

Why Did Brown Hare Lepus europaeus Disappear from Some Areas in Central Poland?

Brown hares originated in the open steppe grasslands of Eurasia and have adapted very successfully to a mixed, arable agriculture environment. In the last decades of the 20th century, a decline in brown hare populations has been observed in many European countries. In this study, we documented a long-term (1965–2018) decline in the hare population in a field and forest mosaic in central Poland (from over 30 ind./100 ha in the mid-1960s to 1–2 ind./100 ha in the past decade). We showed that the recent autumn densities were the same as compared to the preceding spring densities (suggesting a low recruitment rate) and that the recent densities recorded in the fields were no longer higher than in the forests (probably due to a decrease in the habitat quality of arable lands). We also showed that the share of hares in a red fox diet was now very low (0.1% vs. 13% in the past). We compared the recent (2004–2018) population estimates to another area that was located 70 km east (with a similar habitat structure, a community of predators and climate conditions, but with less intense agriculture), where the hare population was increasing. We suggested that the farming practices were the most important factor for the hare population decrease in our study area.

Spatio-temporal monitoring of mercury and other stable metal(loid)s and radionuclides in a Croatian terrestrial ecosystem around a natural gas treatment plant.

The natural gas industry bears a certain contamination risk to human and biota due to, among others, mercury, arsenic, and naturally occurring radioactive material content in gas. We tracked multiple stabile metal(loid)s and radionuclides within the natural gas treatment plant Molve, Croatia, ecosystem during the last decade through a comprehensive monitoring of soil, earthworms, moss, livestock (blood, milk, hair, urine, and feces from cows), and wildlife animals (brain, muscle, liver, and kidney of European hare and pheasant). The level of mercury and other stable metal(loid)s has shown temporal variation, but without an obvious trend. The found spatial differences in soil and earthworms were based on the differing soil characteristics of the sampled locations and exceeded the maximal allowable concentration of arsenic and zinc for agricultural soil. The status of essential copper, selenium, and zinc in cows, hares, and pheasants inclined towards deficiency. The measured stable metal(loid) levels in soil and animal samples were generally in the same range of values reported in earlier decades from the same area or non-polluted areas across Europe. The consumption of local cow and game products (e.g., milk, meat) can be considered safe for human health, although game offal is advised to be avoided as a food item due to the low risk of lead and cadmium's adverse effects. Although the activity concentrations of some radionuclides in moss were higher than reported for pristine areas, transfer from soil to moss was assessed as average (except for lead-210). Radiological risk to human and biota around the gas treatment plant Molve was estimated as negligible.

Outbreak of Cronobacter turicensis in European brown hares (Lepus europaeus).

This is the first report of acute deaths in five European brown hares (Lepus europaeus) attributed to mucoid and necrotizing typhlocolitis caused by genetically different Cronobacter (C.) turicensis strains in northeastern Austria. As this opportunistic pathogen is mainly known for causing disease in immunocompromised humans and neonates, this previously unrecognized potential for a spill over from a wildlife reservoir to humans warrants further attention.

The Brown Hare (Lepus europaeus) as a Biomonitor for the Presence of Lead and Cadmium in Vojvodina, Serbia

Summary Lead (Pb) and cadmium (Cd) are heavy metals considered possible contaminants of water, soil and air (especially when occurring as a consequence of human activities in agriculture or industry), and can be found in the liver or kidneys of animals, thus serving as indicators of pollution. Vojvodina is a northern province of the Republic of Serbia which boasts very intensive agricultural production, especially crop production. The brown hare is well-adapted and abundant in Vojvodina. As a complete herbivore, it has the potential to be a good biomonitor for the presence of lead and cadmium in the chosen biotope. A total of 60 samples of hare livers were collected and analyzed immediately after hunting. The average concentration of lead in all the liver samples analyzed was 851.43 µg/kg of wet tissue. The lead concentrations determined at three different sites in Vojvodina (namely Odžaci in Bačka, Rusko selo in Banat and Kraljevci in Srem) were not statistically significant. However, the average lead concentrations at all the sites were above the permitted level (500 µg/kg of wet tissue). The maximum amount of lead determined was 2,302 µg/kg of wet tissue, i.e. almost five times above the permitted level. The cadmium concentrations in all the samples analyzed ranged from 12.90 to 1183.00 µg/kg of wet tissue. The average cadmium concentrations determined at three different sites were found statistically significant, suggesting a local source of contamination. The average cadmium concentrations at sites I, II and III were 65.57, 205.91 and 413.99 µg/kg of wet tissue, respectively. The average cadmium concentrations determined at the sites considered were below the permitted level, although exceeding the legal limit in some of the samples analyzed.

Gastrointestinal Parasite Community and Phenotypic Plasticity in Native and Introduced Alien Lagomorpha.

Simple SummaryThe introduction of alien species outside their native range represents one of the main threats to biodiversity conservation and it is mainly driven by human activities. In this work, we used the introduction of an alien lagomorph (Sylvilagus floridanus) outside its natural range as a case study to describe and evaluate the long-term effects on the native lagomorph community. In particular, S. floridanus was host to different exotic parasites, which adapted to new biotic and abiotic conditions and, as a consequence, invaded and largely altered the parasite community of native Lagomorpha species. This work represents the first exploratory study on the ecological macro-community formed by native and alien host species and their parasitofauna. Further efforts are needed to fully understand the strategies and factors conditioning the evolution of these specific parasite communities, and more in general the factors influencing the effect and evolution of alien pathogens in a new geographic area.The Convention on Biological Diversity classifies “Invasive Alien Species” as those whose introduction and spread represents a threat for biodiversity. Introduction of alien pathogens, including parasites, is one of the main consequences of the introduction of invasive alien species. The objective of this work was to assess the parasite community composition in native lagomorphs (Lepus europaeus and Lepus timidus varronis) in sympatric and non-sympatric conditions with an alien lagomorph (Sylvilagus floridanus), and to evaluate the phenotypic traits of exotic parasites in such conditions. We firstly describe the characteristics of the parasite community in the different host species (richness, prevalence, abundance and intensity), and, secondly, the phenotypic traits of the observed parasite species in each host. Nine helminths were reported on: eight nematodes (Obeliscoides cuniculi, Trichostrongylus calcaratus, Trichostrongylus retortaeformis, Trichostrongylus affinis, Trichuris leporis, Trichostrongylus colubriformis, Passalurus ambiguus, and Nematodirus sp.) and one unidentified cestode. In addition, exotic parasites showed significantly different phenotypic plasticity after spillover from S. floridanus to L. europaeus, whereas endemic parasite species were not isolated in the alien S. floridanus. Our results highlight that the community of autochthonous and allochthonous Lagomorpha in northwestern Italy represents an extremely interesting system for modelling ecological and evolutionary interactions between parasites and their hosts.

The European Hare (Lepus europaeus) as a Biomonitor of Lead (Pb) and Cadmium (Cd) Occurrence in the Agro Biotope of Vojvodina, Serbia

Simple SummaryHeavy metals such as lead and cadmium are pollutants and can be found in different biotopes. Hares, due to their natural habitat, numbers, range and choice of food are good bioindicators of the occurrence of heavy metals. Vojvodina, northern province of Republic of Serbia, has intensive agriculture with about 77.8% of agricultural land. In such agricultural biotope, we discovered that out of the two studied heavy metals in the liver of hare’s it seems that the occurrence of lead is more of the importance. In the majority of locations the cadmium concentrations were in the permitted level by Serbian legislative. However, the situation with the occurrence of lead was completely different. Only on the two out of seventeen locations average concentrations were in the permitted level.The aim of this study was to investigate the occurrence of two heavy metals, lead and cadmium, in European hare liver samples, collected in agro biotope of northern Serbian province Vojvodina. Heavy metals such as lead (Pb) and cadmium (Cd) do not have any biological function in the animal body; however, they can be found due to the pollution in the environment. For the purpose of this study, in 196 samples from 17 different locations hare livers were analyzed for the occurrence of lead and cadmium. All samples were taken from hares harvested during the regular hunting season. The average value for lead in all analyzed samples was 884 µg/kg fresh weight (fw), with the range 59–3700 µg/kg fw. Only samples from two locations had the average concentration of lead which was within the permitted limit by the Serbian regulation. The average cadmium level in all samples was 243 µg/kg fw. The range of all samples was from 0 to 1414 µg/kg fw. Our research indicates that out of two investigated heavy metals, the occurrence of lead is more common and at a higher concentration in the agricultural development region of Vojvodina.

Abandonment of Silvopastoral Practices Affects the Use of Habitats by the European Hare (Lepus europaeus)

Silvopasture, a traditional agroforestry practice, combines the presence of trees, shrubs, herbage, and livestock in time and space to provide multiple ecosystem services that contribute to human well-being. However, the abandonment of traditional agroforestry practices across Europe has led to substantial changes in vegetation characteristics, mainly due to woody plant expansion and, as a consequence, changes in wildlife that rely on open habitats. This study examines the effects of a 20-year abandonment of silvopastoral practices (i.e., livestock grazing and fuelwood harvesting) in a typical agroforestry Mediterranean landscape (kermes oak shrubland, natural grassland, and olive groves) on European hare (Lepus europaeus) habitat use. We estimated tree, shrub, and herb cover using a densitometer and hare habitat use using pellet counts within 2004-m2 rectangular plots in 2002, 2011, and 2021. Hare pellet density in olive groves was significantly lower in 2021 compared to 2002, while the opposite trend was found in grassland for the same period. Woody plant cover expanded from 2002 to 2021. We suggest that the woody plant encroachment that followed the abandonment of traditional silvopastoral practices in the area is the main driver behind the reported decline in hare use of the habitat, as it became less open and therefore less favorable for the species. Maintaining a mosaic of open and closed habitats at the landscape level, which was once provided by silvopastures, is vital for the conservation of this species.

Relation of pine crop damage to species-specific density in a multi-ungulate assemblage

Deer management in forest ecosystems requires information on deer densities and impacts to inform culling decisions with a known target density for acceptable damage levels. In multi-ungulate assemblages, managers need knowledge of relative impacts by different species or guilds. In an extensive (195 km2) conifer forest in eastern England, we related Scots pine (Pinus sylvestris) leader damage (% dominant shoots browsed) in 48 restocked stands (1–3 years growth) over multiple years (n = 79 observations) to species-specific annual muntjac (Muntiacus reevesi), roe (Capreolus capreolus), fallow (Dama dama) and “large deer” densities (composite of annual fallow and multi-year mean red deer Cervus elaphus) using generalized mixed effects models. Forest-wide density surface models were calibrated through intensive annual thermal imaging distance transects and local densities around stands resampled within confidence bounds. Models also examined effects of ground vegetation and hare presence (Lepus europaeus). More pine leaders were browsed at higher fallow or large deer densities (22% and 18%, respectively, increased leader damage across inter-quartile range). Leader damage intensity was not influenced by ground vegetation, hares, muntjac (across the range 8.3–41.6 individuals km−2) or roe deer density (1.7–19.4 individuals km−2). To reduce pine crop damage to economically acceptable levels, managers need to reduce fallow deer to a density as low as 0.6 individuals km−2 (CI = 0.06–1.44, which is considered impractical) or reduce combined large deer density to 2.3 (CI = 1.18–3.46) individuals km−2. Reducing muntjac or roe abundance would minimally affect leader damage in this system, but may be important for other tree species. Multi-species deer management requires species-specific understanding of impacts and robust density estimates.