One, no one, or one hundred thousand: how many wolves are there currently in Italy?

Large carnivores in Italy and other European countries are protected by law to ensure their long-term conservation. Estimates of abundance and demographic trends of their populations are crucial for implementing effective conservation and management strategies. However, it is challenging to obtain basic demographic parameters for elusive species such as the wolf (Canis lupus). Monitoring wolf populations by standard field methods or non-invasive genetic approaches requires huge human efforts and may be exceedingly expensive on a nation-wide scale. Aiming to obtain a first approximate estimate of wolf distribution and abundance in Italy, we developed a systematic review procedure to analyze published data obtained from a variety of sources. We deduced relevant information on wolf presence and numbers from 20 peer-reviewed studies or official reports, and from 241 Standard Data Forms of Natura 2000 sites in Italy, referring to the period 2009–2013. We estimated the species abundance by combining the number of individuals reported in each study area with the values obtained by multiplying the estimated number of packs for the average pack size. Comparing our estimates with those previously reported, we evaluated the qualitative trend of the population for each of the two management units: Alps and Apennines. Results showed the occurrence of approximately 321 wolf packs in Italy, corresponding to 1269–1800 wolves, possibly still underestimated. The Apennine sub-population seems to be almost the double in size (with ca. 1212–1711 wolves in the period 2009–2013) compared to previous estimates (600–800 wolves between 2006 and 2011). The Alpine sub-population, despite its ongoing eastwards expansion, appears rather stable (with 57–89 wolves). Overall, the current wolf population size and trends seem favorable, although the species is still locally threatened by widespread poaching and accidents. These results represent the first estimate of abundance for the whole Italian wolf population in the last 40 years. Such information can be used to implement sound conservation strategies, especially in critical human-dominated landscapes, where conflicts with human activities and increasing rates of hybridization with free-ranging domestic dogs call for updated management plans.