The Italian Action Plan for the Endangered Eurasian Otter Lutra Lutra
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Hystrix It. J. Mamm. (n.s.) 21(1) (2010): 19-33 THE ITALIAN ACTION PLAN FOR THE ENDANGERED EURASIAN OTTER LUTRA LUTRA 1* 2 3 4 ANNA LOY , LUIGI BOITANI , LAURA BONESI , ANTONIO CANU , 5 5 6 ANTONIO DI CROCE , PIER LUIGI FIORENTINO , PIERO GENOVESI , 7 6 8 LIVIA MATTEI , MANUELA PANZACCHI , CLAUDIO PRIGIONI , 6 9 ETTORE RANDI , GABRIELLA REGGIANI 1Dipartimento di Scienze e Tecnologie per l’Ambiente e il Territorio, Università del Molise, Contrada Fonte Lappone, 86090 Pesche, Italy *Corresponding author, E-mail: [email protected] 2Dipartimento di Biologia Animale e dell’Uomo, ‘Sapienza’ Università di Roma, Viale Università 32, 00158 Roma 3Riverside Place 73, Cambridge CB5 8JF, UK 4 WWF/ WWF Oasi, Via Allegri 1, Roma, Italy 5Ministero dell’Ambiente e della Tutela del Territorio e del Mare, Via Cristoforo Colombo 44, 00147 Roma, Italy 6 Istituto Superiore per la Protezione e la Ricerca Ambientale, Via Cà Fornacetta 9, 40064 Ozzano Emilia (BO), Italy 7Corpo Forestale dello Stato, Via della Polveriera 43, 63040 Ascoli Piceno (AP), Italy 8 Dipartimento di Biologia Animale, Università di Pavia, Via Taramelli 24, Pavia, Italy 9 Istituto di Ecologia Applicata, Viale dell’Università 32, 00186 Roma, Italy Received 23 March 2010; accepted 20 June 2010 ABSTRACT - Although recent evidence of the species recovery has been reported for many European countries, in Italy the Eurasian otter Lutra lutra is still considered endan- gered. Otter populations are confined to few river basins in the southern part of the peninsu- la and these are both geographically and genetically isolated from other European popula- tions. This critical situation led the Italian Ministry of Environment to promote the produc- tion of an Action Plan for the otter in Italy, whose methods, aims and actions are briefly summarized. Key words: Eurasian otter, Lutra lutra, conservation, management, Italy RIASSUNTO - Nonostante i segnali di recupero segnalati in molti paesi europei, la lontra Lutra lutra è ancora una delle specie più minacciate della fauna italiana, in virtù delle pic- cole dimensionino della popolazione e del suo isolamento , sia geografico, sia genetico, dal resto delle popolazioni europee. Sulla base di queste considerazioni il Ministero dell’Ambiente e della Tutela del territorio e del Mare ha recentemente promosso la realiz- zazione di un Piano d’Azione Nazionale per la Conservazione della Lontra, i cui contenuti, obiettivi, e azioni sono riassunti in questo lavoro. Parole chiave: Lontra euroasiatica, Lutra lutra, piano d’azione, Italia 19 Loy et al. INTRODUCTION ropean populations (Prigioni et al., 2006a, 2007; Randi et al., 2003; Mucci In the last four decades of the 20th cen- et al. 2010). Moreover the population is tury, the Eurasian otter Lutra lutra un- divided in two isolated sub- derwent a large, significant decline populations: the larger occurring in throughout much of Europe. Several Campania, Basilicata, Calabria and factors have been suggested to explain Puglia regions, while the smaller, only this decline, including a reduction of recently discovered nucleus, occurs in food supply, pollutants, human perse- four river catchments of Molise and cution and the destruction of riparian Abruzzo regions (Loy et al., 2004; Fu- vegetation. These factors played differ- sillo et al., 2004; Marcelli, 2006). ent roles in each European country, Recent expansion of the otter popula- making it difficult to generalize con- tions in Slovenia (Honigsfledt, pers. servation strategies at a continental lev- com.) and Austria (Kranz, pers. com.) el. Accordingly, the action plan for ot- let hypothesize the near colonization of ter species produced by the IUCN-Otter the River Isonzo catchment (NE Italy). Specialist Group (Foster-Turley et al. Compared to other populations in Eu- 1990) gives specific indications for the rope, that in e Italy is recovering rather implementation of national action slowly, with signs of the species ex- plans. The decrease in the concentra- panding its range having only recently tion of harmful pollutants in the envi- become evident (De Castro and Loy, ronment due to more stringent regula- 2007; Prigioni et al., 2007). tions and the enactment of legal protec- This critical situation led the Italian tion have allowed otter populations to Ministry of Environment to promote gradually recover since the 1980s in the production of an Action Plan (AP several European countries (Fig. 1). hereafter) for the otter in Italy (Panzac- This positive trend led to downgrade chi et al., 2010). The efficacy of this the species from “Vulnerable” (Reuther tool depending on both its adherence to and Hilton-Taylor, 2004) to “Near the local situation and capacity to in- Threatened”, at both global and Euro- volve stakeholders (Council of Europe, pean scale (IUCN, 2004, 2007). De- 1998). To achieve this, the Italian Min- spite this positive trend the species is istry of Environment established two still considered as “Endangered” in Ita- teams: the first team (TSB - Technical ly (Boitani L., Genovesi P. and Rondi- and Scientific Board) was charged with nini C., in prep). collecting data and drawing up the During the first half of the 20th century plan; the second, the Institutional the otter was still widespread through- Board (IB) was responsible for promot- out Italy, but its distribution is now ing the participation and involvement confined to the southern part of the pe- of all the territorial authorities within ninsula. The residual population is rela- the current range of the otter (Regional tively small (estimated at about 250 and Provincial administrations, Nation- adult individuals surviving on 50 river al and Regional parks, government en- catchments) and is both geographically vironmental agencies, NGOs). The and genetically isolated from other Eu- teams met periodically to share and 20 Italian Action Plan for otters Figure 1 - Distribution of the otter in Europe (from European Mammal Assessment http://www.iucnredlist.org ) and detail of the otter range in Italy. discuss the different stages of the plan The otter is considered a “flagship spe- development. The plan represents an cies”, at the top of the fresh water food official document of the Italian gov- chain and strictly dependent on riparian ernment. To maximize and optimize vegetation cover (Lunnon and Rey- the efficacy of the plan through a nolds, 1991; Bifolchi and Lodé, 2005), shared strategy of management, all in- consequently the Action Plan was also stitutions signed an official agreement. conceived in the light of the key role of 21 Loy et al. otters in the conservation of aquatic 2006b; Prigioni, 1997; Cannetiello et ecosystems, these being among the al. 2005; Fusillo, 2006) and trout (Sal- most endangered habitats in Europe mo trutta) in mountain streams. Otters (Dudgeon et al., 2006). also prey upon alien species, such as A special effort was devoted to stan- largemouth bass (Micropterus sal- dardize methods, monitoring efforts moides), carp (Cyprinus carpio;), gold- and actions in conformity to the Euro- fish (Carassius auratus), catfish (Icta- pean conservation strategy. This aim lurus melas) and red swamp crayfish was achieved by adapting the recom- (Procambarus clarkii), which some- mendations of the IUCN Otter Special- times may form the bulk of its diet ist Group for Europe (IUCN, 2004) to (Prigioni et al. 2006b; Blanco Garrido the Italian legal, economic, and social et al., 2008; Loy et al., 2009). context. In these terms, we argue that it The behavioural ecology of Italian ot- may represent an effective tool to en- ters has been little investigated. Radi- hance the protection and conservation otelemetric data on wild otters are of the otter in Europe. available for only one male and one female from the Cilento National Park, BIOLOGY AND ECOLOGY OF while six animals (three females and ITALIAN OTTERS three sterilized males) were experimen- tally released from an enclosure in the The Eurasian otter is a solitary and ter- Maiella National Park. These data indi- ritorial semi-aquatic carnivore distri- cate that home range size varies be- buted widely throughout Eurasia, tween 36 - 44 km for males and 30 km where it inhabits streams, rivers, ponds, for females (Mattei et al., 2005a, b, c, lakes and coastal areas. In Italy the d; Fusillo, 2006; Quaglietta, com. species is confined mainly to the me- pers.). A non-invasive genetic sampling dian course of the main rivers and their carried out in the Pollino National Park tributaries, rarely occurring in coastal yielded maximum values of 35 km and areas (Panzacchi et al., 2010). The Eu- 21 km of river stretches (Prigioni et al., rasian otter is an opportunistic feeder 2006c), each including the overlapping and in Mediterranean freshwater bo- ranges of 4-6 different otters. The same dies, its diet varies spatially and seaso- study allowed an assessment of otter nally in relation to fish availability density, which, in the core area of the (Remonti et al., 2008, 2009).Whenever Italian otter population, ranged from fish are scarce otters rely on alternative 0.18 to 2.0 ind/km (Prigioni et al., prey, most frequently amphibians and 2006a). Variation in otter marking in- crustaceans (Ruiz-Olmo et al. 1989; tensity at the periphery of the range Prigioni et al., 2006b; Fusillo, 2006; suggested otter density is probably Smiroldo et al., 2009). As in the rest of lower in these areas (Prigioni et al., Europe, the diet is dominated by cypri- 2006d, Fusillo et al., 2007). nids in lentic waters, mainly barbs The average distance covered in one (Barbus spp.), European chub (Leucis- night by females was 11 km and by cus cephalus), and orange-fin roaches males 15 km (Mattei et al., 2005b).All (Rutilus rubilio) (Prigioni et al., 1991, otters monitored in Italy were largely 22 Italian Action Plan for otters nocturnal (80-100% of total activity for the protection of wildlife (L.N. was at night; Mattei et al., 2005c; Fu- 157/1992, art.