Eurasian Otter Lutra Lutra in Developing Countries: a Resurvey of Albania 22 Years After the Fall of Communism

Eurasian otter Lutra lutra in developing countries: a resurvey of Albania 22 years after the fall of communism A LESSANDRO B ALESTRIERI,SIMONE M ESSINA,FRANCESCA P ELLA C LAUDIO P RIGIONI,NICOLA S AINO and M AURO F ASOLA Abstract In countries with emerging and developing econ- persistent organic pollutants, especially synthetic pesticides omies the need to promote development and the lack of in- (lindane, DDT) and chlorinated biphenyls (Ruiz-Olmo formation on the status of the Near Threatened Eurasian et al., ). otter Lutra lutra have given rise for concern about the con- Although most industrially developed countries have servation status of the species. In Albania information about made progress in controlling pollution and implementing the distribution of this otter dates from .In we re- conservation measures, in transitional or developing econ- surveyed sites previously surveyed in , and a further omies biodiversity governance is hindered by ongoing insti- sites throughout the country. At each site nine habitat tutional change and the need to promote economic variables of potential importance to otters were recorded development, which often result in overexploitation of natu- and analysed. Overall the distribution pattern in did ral resources (CEC, ; Kluvánková-Oravská et al., ). not differ from that recorded in , although a reduction Approximately % of the countries within the Eurasian in marking intensity suggested a possible decline in otter otter’s range have been listed as emerging and developing numbers. Distribution of the otter has been influenced by economies by the International Monetary Fund (IMF, land use and human density, suggesting man-induced habi- ), and the species’ population trend in the eastern part tat changes since the fall of communism may have affected of its range was the basis for its categorization as Near the quality and fragmentation of otter habitats. Threatened on the IUCN Red List in (Ruiz-Olmo et al., ). Keywords Albania, distribution, Eurasian otter, habitat Information about the current status of the species in change, Lutra lutra, monitoring, standard survey, tran- many developing countries is scarce. Although the otter sitional countries population is increasing in Poland (Romanowski, ) This paper contains supplementary material that can be and may not have declined in Hungary during the second found online at http://journals.cambridge.org half of the th century (Heltai et al., ), the species has reportedly declined in Turkey (Kayaöz, ; Özdemir, ), the South Caucasus region (Georgia, Armenia and Azerbaijan; Gorgadze, ), Belarus Introduction (Sidorovich, ), Nepal (Bhandari, ) and Morocco (Delibes et al., ). ollowing a dramatic decline in both range and popu- In Albania the communist era ended in . The tran- lation in the second half of the th century, the F sition from centralized management of land and natural Eurasian otter Lutra lutra is recovering in several resources to a market-oriented economy has caused wide- European countries, including the UK (Crawford, ), spread damage to the environment (Jansen et al., ), Sweden (Roos & Rigét, ), Denmark (Elmeros et al., especially to aquatic ecosystems of the western lowlands, ), France (Janssens et al., ), Spain (Ruiz-Olmo & as a result of increased urbanization, overexploitation of Delibes, ) and Italy (Prigioni et al., ). This recovery woodland and ineffective waste management (Cullaj et al., is probably largely attributable to efforts in the s to ban ; Keukelaar et al., ). Except for a few more recent surveys in the southern part ALESSANDRO BALESTRIERI (Corresponding author) and NICOLA SAINO Department of the country (rivers Seman and Drinos; Bego et al., ; of Biosciences, University of Milan, Via Celoria 26, 20133 Milan, Italy Hysaj et al., ), information about the distribution of E-mail [email protected] the otter in Albania dates back to , when during – SIMONE MESSINA Department of Biology and Biotechnology, Sapienza University, Rome, Italy May Prigioni et al., surveyed sites, mostly in the western lowlands and in the upper catchment of the River Shkumbin FRANCESCA PELLA IUCN, Rruga Abdi Toptani, Torre Drin, Tirana, Albania (Prigioni et al., ). The rationale for the survey method CLAUDIO PRIGIONI and MAURO FASOLA Department of Earth and Environmental ’ Sciences, University of Pavia, Pavia, Italy was based on Erlinge s recommendations; stretches of river up to m long were surveyed for otter spraints Received July . Revision requested September . Accepted October . First published online February . and footprints on both banks (Chanin, ). A minimum Oryx, 2016, 50(2), 368–373 © 2015 Fauna & Flora International doi:10.1017/S0030605314000921 Downloaded from https://www.cambridge.org/core. IP address: 170.106.202.8, on 28 Sep 2021 at 05:15:18, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0030605314000921 Eurasian otter in developing countries 369 coastal lagoons (Butrinti, Narta, Ceke, Merxhani, Patok, Viluni; Peja et al., ). Mean transect length was m (range – m). The most thoroughly surveyed catchments were those of the rivers Shkumbin (n = ), Vjosa (n = ), Mat (n = ) and Ishëm-Erzen (n = ); relative to their total length, few sites were located in the catchments of the rivers where otter occurrence had been confirmed recently. All sites were georeferenced using a global posi- tioning system. To avoid bias as a result of variation in ex- perience with sampling, all surveys were carried out by the same trained staff. Sprainting sites were identified as places with spraints separated by at least m from other spraints (Kruuk et al., ). Following Prigioni et al. () an index of otter marking intensity was calculated as the number of sprainting sites or spraints per m. We assumed marking intensity represented a broad index of relative abundance (Mason & Macdonald, ). The percentage of sites where otters were present in was compared to that found in (χ test), with respect to both the total number of sites (n = ) and the number of sites surveyed in both years (n = ). For the latter sample the distribution of sites with presence and absence was compared using a × summary table of coincidences and discrepancies. For each site on a watercourse five habitat variables of potential importance to otters (Prenda et al., ; Remonti et al., ) were recorded visually in the field (Supplementary Table S). Watercourse width and depth FIG. 1 Sites surveyed for the Eurasian otter Lutra lutra in were estimated at intervals of c. m and the mean values Albania in . Filled and unfilled circles indicate otter presence for each site were assigned to one of four classes (# ., .– and absence, respectively. ., .–. or . m, and # ., .–., .–. or . m, respectively). Water speed was categorized as stag- nant, slow or moderate–high. The dominant land use within distance of m was surveyed per site and the otter a m wide belt on both river banks was estimated and ca- was presumed absent if no sign was detected along the tran- tegorized as bare soil, crops, pasture/shrubs or woods. sect. To update information on the distribution of the Water pollution was categorized as absent (transparent Eurasian otter in Albania and to assess the impact of water in $ % of watercourse depth, without any sign of ’ political and economic changes on the species conservation pollution), low (less transparent water, solid waste on the by comparing current and past range, we resurveyed the banks), medium–high (clear signs of pollution, such as major watercourses and coastal lagoons of Albania in bad smell, turbidity, foam). Mean altitude was recorded summer . for each site (# , –, –, . m). To assess the influence of human disturbance on otter occurrence, Methods using GE-Path v. (Sgrillo, Ilhéus, Brazil), we assessed the overall percentage cover of agricultural and urban Following the same protocol used by Prigioni et al. (), areas in a km area centred on each site, by superimposing during June– July we resurveyed the sites sur- a × m grid on satellite images provided by Google veyed in , and an additional sites, thus surveying all Earth (Google, Mountain View, USA). Results were categor- the major river catchments of Albania (Fig. ). We used a ized as # , .–, .– or . %. : , road map to select sites, which were chosen for Otter presence/absence was then modelled against the ease of access, mainly at road bridges, to maximize the prob- predictor variables by backward stepwise logistic regression, ability of finding signs quickly (Chanin, ). Sites were using Wald’s test to examine the statistical significance of separated by at least km. Twenty-nine sites were on each coefficient in the model. To avoid collinearity, which main rivers, on tributaries, seven on canals, five on can inflate the standard errors of the estimates of model lakes (Shkodrës, Ohrit, Vaut të Dejës, Fierzes) and six on coefficients and produce unreliable results (Hosmer & Oryx, 2016, 50(2), 368–373 © 2015 Fauna & Flora International doi:10.1017/S0030605314000921 Downloaded from https://www.cambridge.org/core. IP address: 170.106.202.8, on 28 Sep 2021 at 05:15:18, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0030605314000921 370 A. Balestrieri et al. Lemeshow, ), the correlation between the predictors TABLE 1 Otter Lutra lutra mean marking intensity along seven was measured by Spearman’s coefficient. Model variables major rivers in Albania

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