Assessing the threatened status of Testudo hermanni boettgeri Mojsisovics, 1889 (Reptilia: Testudines: Testudinidae) population from Romania

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Assessing the threatened status of Testudo hermanni boettgeri Mojsisovics, 1889 (Reptilia: Testudines: Testudinidae) population from Romania
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  North-Western Journal of Zoology Vol. 6, No. 2, 2010, pp.190-202 P-ISSN: 1584-9074, E-ISSN: 1843-5629 Article No.: 061118   ©NwjZ, Oradea, Romania, 2010 North-West J Zool, 6, 2010www.herp-or.uv.ro/nwjz Oradea, Romania   Assessing the threatened status of Testudo hermanni boettgeri Mojsisovics, 1889(Reptilia: Testudines: Testudinidae) population from Romania Lauren ţ iu ROZYLOWICZ* and Mariana DOBRE   University of Bucharest, Centre for Environmental Research and Impact Studies, 1, Nicolae B ă lcescu, 010041, Bucharest, Romania*Corresponding author: L. Rozylowicz, Tel/Fax +40213103872, Email: laurentiu.rozylowicz@g.unibuc.ro Abstract . The Hermann tortoise ( Testudo hermanni boettgeri Mojsisovics, 1889) is present in Romaniaat its range limit. The main range is located in the Southwestern part of the country, in a sub-optimalsub-Mediterranean climate. Testudo hermanni boettgeri is also found in the Southeastern part of thecountry, the population there being insignificant to be included in our study. The range fromSouthwestern part of Romania has a surface of ~4420 sq km, from which only ~672 sq km isfavorable to the tortoise. From the range extension point of view, the Hermann tortoise is asubspecies with a restrictive habitat, and the population is strongly declining—a tendency that mostlikely will continue in the future. This decline is accentuated by the habitat loss. The main threats forthe Hermann tortoise are due to housing and urban area encroachment, tourism and recreationareas, annual and perennial non-timber crops, mining and quarrying, energy production andmining, recreational activities, increase in fire frequency/intensity, droughts, temperature extremes,climate change and severe weather. The threatened status established according to IUCN criteria forthe regional level under uncertainty have led to framing the species in the endangered ENB1ab(i,ii,iii,v) category. Key words:   Testudo hermanni boettgeri , conservation, threats, Romania, IUCN Red List Introduction The tortoises are among those animals whoseIUCN status is being revised. (Cox & Temple2009). Survivors of several geological periods,they seem to restrain their territory due torapid climate change (Gibbons et al. 2000).Threats like land use changes, road infra-structure development and global climatechange (Primack et al. 2008) are making Testu-do hermanni and Testudo greaca vulnerable(Cog ă lniceanu & Venczel 1993, Iftime 2000–2001, Iftime 2005). Testudo hermanni Gmelin,1789 and its subspecific taxons’ nomenclatureis controversial, and there are several nomen-clatural combinations (Fritz & Havaš 2006,Lapparent de Broin et al. 2006). The currentlyaccepted taxonomic framing for the subspeciesfrom Romania is: Order: Testudines; Superfa-mily: Testudinoidea; Family: Testudinidae;Scientific name for the species: Testudo herman-ni ; Species authority: Gmelin, 1789; Scientificname for the subspecies Testudo hermanniboettgeri ; Subpecies authority: Mojsisovics, 1889(Fritz & Havaš 2006). Testudo hermanni boettgeri  beneficiates from different legal protectionstatus such as natural monument according toRomanian Academy, and protected speciesunder both CITES Convention and HabitatDirective (2006/105/EC 2006, Rozylowicz2008, UNEP-WCMC 2010).The populations of both species are foundin Romania at their range edge (Gasc et al.1997), with T. hermanni boettgeri also beingisolated from the other groups (Cheylan 2001).This separation from the main range appeared  Threatened status of Testudo hermanni boettgeri population from Romania   North-West J Zool, 6, 2010   191relatively recent, the population not being yetgenetically distinct (Fritz et al. 2006). Despitethe fact that there is clear evidence, whichmakes Testudo hermanni a strong candidate fora threatened status (Cheylan 2001), at EU27level the species was classified after IUCN asbeing in a safe category—Near Threatened(Cox & Temple 2009). To set up nationalpriorities in conservation a regional assessmentof the threatened status is required. (IUCN2003, Cog ă lniceanu & Cog ă lniceanu 2010).The goals of our study were 1) to evaluatethe threatened level of the species at thenational level, according to IUCN 3.1 criteriathat are applicable to regional level (IUCN2001, 2003) and 2) to identify the conservationmeasures that are needed in order to reducethe effects of these threats. Methods To assess the threatening status of Hermann’s tortoise atthe regional level, we used a spatially explicit approach,which allows incorporating uncertainties in the inputdata (IUCN 2003, Mace et al. 2008). The analysis wasconducted with RAMAS Red List Professional (Akçakaya& Root 2007) by considering the following data: Species’taxonomic classification, Life history, Geographic range,Population information, Habitat preferences, Majorthreats and Conservation measures.Generation length, parameter that determines theperiod for assessing past changes and their estimation forthe future, was calculated using the age of the firstreproduction and adult survival rates (SPWG 2010).Data concerning the distribution recorded threegenerations ago were obtained from Fuhn and & Vancea(1961), occurrence points being located with a 2 kmprecision. For mapping current distribution, we haveused recent studies presenting information aboutHermann’s tortoise occurrence in its Southwestern range(i.e. Covaciu-Marcov et al. 2005, Iftime 2005, Rozylowicz2008, Covaciu-Marcov et al. 2009a).For life history, biometric characteristics, life cycle,clutch parameters, predation, diet, and populationstructure we compiled data from literature (i.e. Cruce & Ş erban 1971, Cruce 1978, Rozylowicz 2008). Bioclimaticcharacteristics of the tortoise range were obtained byextracting the values from the Worldclim 1.4 database(Hijmans et al. 2005) recorded in the 737 points ofoccurrence (Rozylowicz 2008). For habitat preference, weused 2006 Corine Land Cover Map (European Environ-ment Agency 2006). Land use within the area of occu-pancy for the Hermann’s tortoise was extracted using asbackground estimated Area of Occupancy (AOO).The occurrence points used in this study areidentified between 2000 and 2008 and those mentioned inthe recent literature that allowed marking them on themap within an error of maximum 2 km (Rozylowicz2008).The Extent of Occurrence (EOO) for T. hermanniboettgeri was estimated using the convex hull and AOOby counting the number of non-overlapping occupiedcells in a uniform grid, with a grid size of 2 km (a cellarea is ~4 sq km) (IUCN 2001).The density of the tortoise’s population wasestimated for three generations ago, present days andthree generations in the future using available data(Cruce 1978, Rozylowicz 2008), compared with Europeansyntheses data (Cheylan 2001). Estimated size wascalculated by maximum density, average density andminimum density inside of AOO, considering that 25%are mature individuals (Hailey & Willemsen 2000).The major threats and conservation measures for thetortoises were standardized according to IUCN Red ListCriteria (IUCN 2001, 2003), compiling the data fromliterature (e.g. Iftime 2005, Matache et al. 2006, S ă hlean etal. 2008) and our recent observations. Results and discussions1. Specie’s ecology 1.1. DistributionThe Hermann tortoise is a European species,and its range overlaps the Mediterraneanclimate from Spain (Catalonia) to Turkey, withinfiltration through the area with sub-Medi-terranean influence in Romania and Bulgaria(Gasc et al. 1997).The spatial distribution of the Hermanntortoise in SW Romania have been assessed inseveral papers, covering past and presentsituations (Fuhn & Vancea 1961, Iana & Petcu1976, Covaciu-Marcov et al. 2005, Iftime 2005,Covaciu-Marcov et al. 2009a).Outside the Southwestern range, theHermann tortoise was confirmed in Dobrogea(Iftime 2002, Sos et al. 2008), being either a vag-rant specimen brought by people or belongingto populations from Bulgaria. In several papers  L. Rozylowicz & M. Dobre   North-West J Zool, 6, 2010   192have been recorded occurrences from Central(i.e. Ha ţ eg Depression, Jiului Gorge) and East-ern Romania (i.e. Gala ţ i county), rejected byextensive field research – e.g.Covaciu-Marcovet al. (2009b) for Jiului Gorge. The actual range from Romania, withoutpossible vagrant population overlay the South-west part of Romania, in habitats from LocveiMountains, Alm ă  jului Mountains, CernaCorridor, Domogled and Cerna Mountains,Mehedin ţ i Plateau, Co ş u ş tea’s Hills, JianaPlane and B ă l ă ci ţ ei’s Hills (Fig. 1).1.2. Life historyThe Hermann tortoise is a terrestrial tortoise ofmedium size, with an accentuated sexualdimorphism (Rozylowicz & P ă troescu 2004).The average age for the sexual maturity is 8years for males and 9 years for females or forfemales with Straight Carapace Length > 150mm (Cruce & R ă ducan 1975a, Cruce &R ă ducan 1976). The generation length for T.hermanni boettgeri was estimated at 16.9 years.Within the range of the species, the bio-climatic parameters (Table 1) indicate thepresence of a soft sub-Mediterranean climate,with gentle winters and hot summers. Theclimatic data are calculated as an average forthe period 1950–2000. With regard to the meanannual temperature, the range is in a subopti-mal potential (Huot-Daumbremont 2002), thetortoise being constrained in critical times toprotect itself by staying in burrows under-ground to reduce its metabolic rate.The Hermann tortoise has an annual lifecycle divided into two parts: the sleep-hiberna-tion period (November–March/April) and theactive period (March/April–November). Du-ring the sleep-hibernation period, there can beinterruptions when the temperatures areextremely high. During the tropical hot sum-mer days, when the tortoises are not movingfor more than 5 consecutively days, the aesti-vation phenomena appears (Cruce & R ă ducan1975b, Cheylan 2001).Mating occurs several times per annum,from spring to autumn, starting in April. Thereis a synchronization of the whole populationduring the same month in spring (Cruce &R ă ducan 1976). The clutch is usually laid onceper annum, starting in the middle of Maythrough the end of July based on the tempe-rature. Rarely, the tortoise lays a second clutchin August or September (Rozylowicz 2008).The tortoise lays the clutch generally ongentle slopes, rarely flat with sunny aspect.When laying the eggs, the tortoise digs a ditchwith a width of 6–7.5 cm, a length of 7–10 cmand a depth of 5–8 cm (Cruce & R ă ducan 1976).The tortoise lays around 5.28±3.02 eggs pertortoise, with the average weight of the laideggs being 19.96±2.82 grams (Rozylowicz2008).The nests are predated upon by smallcarnivores, insectivores, ungulates and rod-ents. Point observations from the area Bahna–Bucov ăţ – Ţ arov ăţ and Mala–E ş elni ţ a areas haveshown that the predation rate-calculated as thenumber of predated nests per number of ob-served mature females was 98% for Bahna–Bucov ăţ – Ţ arov ăţ and 85% for Mala–E ş elni ţ a(Rozylowicz 2008).The tortoise’s main predators are foxes( Vulpes vulpes ), wild boars ( Sus scrofa ), dogs( Canis familiaris ), martens (  Martens ssp . ),badgers (  Meles meles ), and polecats (  Mustela putorius ). In addition to these predators, feraldogs can also affect the mature individuals byinflicting large wounds. In the sleep-hiberna-tion period, the tortoises can be easily wound-ed or killed by predators like the wood mouse   (  Apodemus sylvaticus ),   fat dormouse   ( Glis glis ),garden dormouse   ( Eliomys ssp . )  , and rats   ( Rattus ssp . )   (Cheylan 2001, Rozylowicz 2008).The tortoise’s diet is made almost exclusi-vely from plant species, mushrooms and mos-ses that the habitat if offering in all the seasonswith biological activity. The point observationsmade by (Rozylowicz 2008) in the Iron GatesNatural Park indicated for the tortoise’s diet  Threatened status of Testudo hermanni boettgeri population from Romania   North-West J Zool, 6, 2010   193the following plant taxa: (leaves, flowers,fruits, very rarely roots):  Arenaria ssp ., Carex ssp ., Cardamine ssp ., Carpinus orientalis, Cirsiumvulgare, Cornus mas, Crataegus monogyna,Crataegus pentagyna, Euonymus latifolius,Hieracium ssp ., Lathyrus ssp ., Leguminosae   family  , Medicago ssp ., Oxalis ssp ., Plantago ssp .,Potentilla ssp ., Poaceae family  , Prunus spinosa,Quercus frainetto, Quercus cerris, Rosa ssp .,Rubus ssp ., Stellaria media, Taraxacum officinale,Trifolium ssp ., Veronica ssp.  , Urtica ssp . This listis incomplete; the tortoise’s diet is morediverse and the studies who have been madeso far were very limited.  Figure 1. Testudo hermanni boettgeri distribution in the southwestern part of Romania Table 1. Bioclimatic parameters within the habitat of T h b. (C.I. = Confidence Interval, S.D. = standard deviation).Parameter Mean CI- 95% CI+95% Min Max S.D.Annual Mean Temperature 10.28 10.14 10.42 8.07 11.36 0.68Temperature Annual Range 30.75 30.62 30.89 28.90 32.10 0.66Mean Diurnal Range 9.47 9.41 9.52 8.60 9.83 0.26Max Temperature of Warmest Month 26.71 26.50 26.92 23.40 28.40 1.018Min Temperature of Coldest Month − 4.04 − 4.17 − 3.91 − 5.50 − 2.60 0.62Mean Temperature of Wettest Quarter 18.17 18.01 18.34 15.53 19.50 0.79Mean Temperature of Driest Quarter 1.54 1.41 1.68 − 0.43 2.90 0.66Mean Temperature of Warmest Quarter 19.77 19.61 19.93 17.18 21.06 0.78Mean Temperature of Coldest Quarter 0.06 − 0.04 0.18 − 1.63 1.20 0.56Annual Precipitation 654.94 647.39 662.49 599.00 780.00 36.66Precipitation of Wettest Month 90.75 89.38 92.12 80.00 114.00 6.64Precipitation of Driest Month 40.25 39.84 40.66 37.00 46.00 1.99Precipitation of Wettest Quarter 233.16 229.69 236.62 206.00 291.00 16.81Precipitation of Driest Quarter 122.77 121.63 123.91 115.00 141.00 5.52Precipitation of Warmest Quarter 214.68 211.23 218.14 187.00 273.00 16.76Precipitation of Coldest Quarter 133.30 131.99 134.60 124.00 151.00 6.33
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