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1.
Sci Rep ; 13(1): 13727, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37608038

RESUMO

Integrating data across studies with traditional microsatellite genetic markers requires careful calibration and represents an obstacle for investigation of wide-ranging species where populations require transboundary management. We used the "yardstick" method to compare results published across Europe since 2002 and new wolf (Canis lupus) genetic profiles from the Carpathian Mountains in Central Europe and the Dinaric Mountains in Southeastern Europe, with the latter as our reference population. We compared each population with Dinaric wolves, considering only shared markers (range 4-17). For each population, we calculated standard genetic diversity indices plus calibrated heterozygosity (Hec) and allelic richness (Ac). Hec and Ac in Dinaric (0.704 and 9.394) and Carpathian wolves (0.695 and 7.023) were comparable to those observed in other large and mid-sized European populations, but smaller than those of northeastern Europe. Major discrepancies in marker choices among some studies made comparisons more difficult. However, the yardstick method, including the new measures of Hec and Ac, provided a direct comparison of genetic diversity values among wolf populations and an intuitive interpretation of the results. The yardstick method thus permitted the integration of diverse sources of publicly available microsatellite data for spatiotemporal genetic monitoring of evolutionary potential.


Assuntos
Lobos , Animais , Lobos/genética , Alelos , Evolução Biológica , Europa (Continente) , Variação Genética
2.
Ecol Evol ; 12(5): e8921, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35600678

RESUMO

The recovery of terrestrial carnivores in Europe is a conservation success story. Initiatives focused on restoring top predators require information on how resident species may interact with the re-introduced species as their interactions have the potential to alter food webs, yet such data are scarce for Europe.In this study, we assessed patterns of occupancy and interactions between three carnivore species in the Romanian Carpathians. Romania houses one of the few intact carnivore guilds in Europe, making it an ideal system to assess intraguild interactions and serve as a guide for reintroductions elsewhere.We used camera trap data from two seasons in Transylvanian forests to assess occupancy and co-occurrence of carnivores using multispecies occupancy models.Mean occupancy in the study area was highest for lynx (Ψwinter = 0.76 95% CI: 0.42-0.92; Ψautumn = 0.71 CI: 0.38-0.84) and wolf (Ψwinter = 0.60 CI: 0.34-0.78; Ψautumn = 0.81 CI: 0.25-0.95) and lowest for wildcat (Ψwinter = 0.40 CI: 0.19-0.63; Ψautumn = 0.52 CI: 0.17-0.78)We found that marginal occupancy predictors for carnivores varied between seasons. We also found differences in predictors of co-occurrence between seasons for both lynx-wolf and wildcat-wolf co-occurrence. For both seasons, we found that conditional occupancy probabilities of all three species were higher when another species was present.Our results indicate that while there are seasonal differences in predictors of occupancy and co-occurrence of the three species, co-occurrence in our study area is high.Terrestrial carnivore recovery efforts are ongoing worldwide. Insights into interspecific relations between carnivore species are critical when considering the depauperate communities they are introduced in. Our work showcases that apex carnivore coexistence is possible, but dependent on protection afforded to forest habitats and their prey base.

3.
PeerJ ; 9: e11678, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34316392

RESUMO

Urbanization impacts biodiversity both directly through physical expansion over land, and indirectly due to land use conversion and human behaviors associated with urban areas. We assessed the response of a common spadefoot toad population (Pelobates fuscus) to habitat loss and fragmentation resulting from urban development by studying changes in size, body condition and age parameters. We compared samples collected in the early 2000s (sample A) and later on during 2012-2014 (sample B). The terrestrial habitats in the study area were severely reduced and fragmented due to the expansion of the human settlement. We found no significant differences in the age parameters between the two sampling periods; the median lifespan shortened from 3.5 (sample A) to 3.0 years (sample B), while the other age parameters were similar in both samples. In contrast, snout-vent length, body mass and body condition experienced a significant decrease over time. Our results suggest that changes in body size and body condition, rather than age parameters, better reflect the response of the common spadefoot toad population to declining habitat quality. Therefore, body measurements can provide reliable estimates of the impact of habitat degradation in amphibian populations.

4.
Zookeys ; (792): 133-158, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30402034

RESUMO

Based on species occurrence records of museum collections, published literature, and unpublished records shared by mammalian experts, we compiled a distribution database for 59 terrestrial mammals populating the extensively protected Dobrogea Region of Romania. The spatial patterns of mammal distribution and diversity was evaluated and systematic conservation planning applied to identify priority areas for their conservation. The spatial analyses revealed that intensive sampling was not directly correlated to mammal diversity but rather to accessibility for inventory. The spatial prioritisation analysis indicated a relatively aggregated pattern of areas with a high or low conservation value with virtually no connecting corridors between them. The significant overlap between Natura 2000 sites and national protected areas induced an over-optimistic vision of the effectiveness and representativeness of existing Natura 2000 network for species found in Annexes II and IV of the Habitats Directive. These results represent a key step in identifying core areas for the protection of mammal diversity and dispersal corridors for improved connectivity, and to guide future conservation efforts in increasing the effectiveness of the existing protected areas in the context of environmental changes.

5.
Ecol Evol ; 7(18): 7134-7144, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28944005

RESUMO

Accurate population size estimates are important information for sustainable wildlife management. The Romanian Carpathians harbor the largest brown bear (Ursus arctos) population in Europe, yet current management relies on estimates of density that lack statistical oversight and ignore uncertainty deriving from track surveys. In this study, we investigate an alternative approach to estimate brown bear density using sign surveys along transects within a novel integration of occupancy models and home range methods. We performed repeated surveys along 2-km segments of forest roads during three distinct seasons: spring 2011, fall-winter 2011, and spring 2012, within three game management units and a Natura 2000 site. We estimated bears abundances along transects using the number of unique tracks observed per survey occasion via N-mixture hierarchical models, which account for imperfect detection. To obtain brown bear densities, we combined these abundances with the effective sampling area of the transects, that is, estimated as a function of the median (± bootstrapped SE) of the core home range (5.58 ± 1.08 km2) based on telemetry data from 17 bears tracked for 1-month periods overlapping our surveys windows. Our analyses yielded average brown bear densities (and 95% confidence intervals) for the three seasons of: 11.5 (7.8-15.3), 11.3 (7.4-15.2), and 12.4 (8.6-16.3) individuals/100 km2. Across game management units, mean densities ranged between 7.5 and 14.8 individuals/100 km2. Our method incorporates multiple sources of uncertainty (e.g., effective sampling area, imperfect detection) to estimate brown bear density, but the inference fundamentally relies on unmarked individuals only. While useful as a temporary approach to monitor brown bears, we urge implementing DNA capture-recapture methods regionally to inform brown bear management and recommend increasing resources for GPS collars to improve estimates of effective sampling area.

6.
Zookeys ; (341): 49-76, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24146598

RESUMO

The reptile fauna of Romania comprises 23 species, out of which 12 species reach here the limit of their geographic range. We compiled and updated a national database of the reptile species occurrences from a variety of sources including our own field surveys, personal communication from specialists, museum collections and the scientific literature. The occurrence records were georeferenced and stored in a geodatabase for additional analysis of their spatial patterns. The spatial analysis revealed a biased sampling effort concentrated in various protected areas, and deficient in the vast agricultural areas of the southern part of Romania. The patterns of species richness showed a higher number of species in the warmer and drier regions, and a relatively low number of species in the rest of the country. Our database provides a starting point for further analyses, and represents a reliable tool for drafting conservation plans.

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