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1.
Curr Zool ; 62(5): 421-430, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29491931

RESUMO

Ecosystem disturbances, such as wildfires, are driving forces that determine ecology and conservation measures. Species respond differentially to wildfires, having diverse post-fire population evolution. This study reports, for first time, the responses of brown hare (Lepus europaeus Pallas, 1778) to wildfires. Hare relative abundance, age ratio, diet quality, body condition, and diseases were studied. Fire influence on vegetation was calculated at a micro-scale level. Hare abundance was lower the first year after wildfires in burned relative to unburned areas. The reverse was found in the second year when hare abundance was higher in burned areas. Hare abundance in burned areas was also higher in the third and fourth years. In the fifth and sixth years after wildfire no significant difference was found in abundance. At a micro-scale level, higher numbers of hare feces were counted in places with greater wildfire influence on vegetation. Age ratio analysis revealed more juveniles in burned areas, but the same number of neonates in burned and unburned areas, indicating lower mortality of juveniles in burned areas. Reduced predation in burned areas provides the most plausible explanation for our findings.

2.
Environ Manage ; 55(1): 19-30, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25344659

RESUMO

Wildlife managers are challenged with the task of deciding whether a management measure is appropriate or not, and furthermore they have to convince others about the merits of their decision. Population decline of some hare species (genus Lepus) has resulted in their Red Listing and conservation measures are being undertaken. Release or restocking is a frequent measure in some countries, and thousands of hares are released annually, mainly for hunting purposes. These hares can be obtained by either intensive or extensive rearing or translocation of the wild animals. Each method entails difficulties and different survival rates in the wild. Survival rates in the wild are low for hares intensively reared in cages but are higher for hares reared extensively in enclosures and wild translocated hares. The benefits of the hare release practice are significantly lower than the action's implementation cost. Hare releases have not increased significantly the wild hare population or the hunting harvest in areas where the practice has been applied. The risk of genetic and evolutionary degradation and pathogen transmission is possible in wild populations. The need for wise management of this practice is evident and the term 'Permitted Transferring Units' should be introduced to denote regions where hares should not be transferred for rearing and release.


Assuntos
Conservação dos Recursos Naturais/métodos , Lebres/fisiologia , Migração Animal , Animais , Animais Selvagens/genética , Animais Selvagens/crescimento & desenvolvimento , Animais Selvagens/fisiologia , Evolução Biológica , Feminino , Lebres/genética , Lebres/crescimento & desenvolvimento , Masculino
3.
PLoS One ; 9(5): e96935, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24806216

RESUMO

West Nile Virus (WNV) is the causative agent of a vector-borne, zoonotic disease with a worldwide distribution. Recent expansion and introduction of WNV into new areas, including southern Europe, has been associated with severe disease in humans and equids, and has increased concerns regarding the need to prevent and control future WNV outbreaks. Since 2010, 524 confirmed human cases of the disease have been reported in Greece with greater than 10% mortality. Infected mosquitoes, wild birds, equids, and chickens have been detected and associated with human disease. The aim of our study was to establish a monitoring system with wild birds and reported human cases data using Geographical Information System (GIS). Potential distribution of WNV was modelled by combining wild bird serological surveillance data with environmental factors (e.g. elevation, slope, land use, vegetation density, temperature, precipitation indices, and population density). Local factors including areas of low altitude and proximity to water were important predictors of appearance of both human and wild bird cases (Odds Ratio = 1,001 95%CI = 0,723-1,386). Using GIS analysis, the identified risk factors were applied across Greece identifying the northern part of Greece (Macedonia, Thrace) western Greece and a number of Greek islands as being at highest risk of future outbreaks. The results of the analysis were evaluated and confirmed using the 161 reported human cases of the 2012 outbreak predicting correctly (Odds = 130/31 = 4,194 95%CI = 2,841-6,189) and more areas were identified for potential dispersion in the following years. Our approach verified that WNV risk can be modelled in a fast cost-effective way indicating high risk areas where prevention measures should be implemented in order to reduce the disease incidence.


Assuntos
Aves/virologia , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Animais Selvagens , Galinhas/virologia , Culicidae/virologia , Feminino , Sistemas de Informação Geográfica , Grécia , Humanos , Densidade Demográfica , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/patogenicidade
4.
Evolution ; 51(4): 1284-1295, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28565477

RESUMO

The effects of hybridization on developmental stability and size of tooth characters were investigated in intersubspecific crosses between random-bred wild strains of the house mouse (Mus musculus domesticus and M. m. musculus). Fluctuating asymmetry (FA) and trait size were compared within and between parental, F1 , backcross, and F2 hybrid groups. The relationship between FA and reproductive fitness within the F1 hybrids was also studied. The results indicated that both FA and character size levels differed significantly between the two subspecies. The F1 hybrids and the recombined groups (backcrosses and F2 hybrids) showed heterosis for both parameters. No significant differences in the FA of fertile and sterile F1 hybrid individuals were found. Comparison of the FA levels obtained in this study with those found in wild populations from the hybrid zone in Denmark showed that the levels of FA were lower in laboratory-bred samples than in the wild populations. This study provides further evidence that, in hybrids, the developmental processes underlying most of the morphological traits we studied benefit from a heterotic effect, despite the genomic incompatibilities between the two European house mice revealed by previous genetical and parasitological studies.

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