New methodology to calculate wolf breeding groups

    – The researchers of the work, in which the CSIC has participated, highlight its applicability at the regional level

    – Evaluate the various factors or human activities that affect the reproduction of the species and its expansion

    ID215
    Specimens of wolves in Portugal (Artur Oliveira)

    Determining the number of wolf breeding groups at the regional level and detecting population trends is the objective of a new methodology designed by a team with the participation of scientists from the Higher Council for Scientific Research (CSIC). The new information treatment method determines the number of reproductive groups that exist at a regional scale and the error of the estimate, which had not been possible to quantify until now.

    The results appear in the journal Conservation biology. According to the researchers, the estimation of breeding packs or herds is the basis of many wolf population monitoring systems in the world. However, the detection probability of the pups is “extremely low”, making it difficult to estimate the number of breeding herds.

    “The management and conservation of large carnivores requires the use of standardized, objective and replicable population monitoring systems. However, monitoring these species on large spatial scales, as is the case of the wolf in Spain, is a logistically complex task that requires great effort and, normally, all the estimates are surrounded by great uncertainty", indicates the researcher of the CSIC José Jiménez García, from the Institute for Research in Hunting Resources (mixed center of the CSIC, the University of Castilla-La Mancha, and the Junta de Comunidades de Castilla-La Mancha). The new system -in which the Ministry of Agriculture, Food and the Environment, the University of Oviedo, the company Asesores en Recursos Naturales and Tragsatec have participated- is based on detecting signs of presence in territorial markings and howling listening stations, integrate the data in a hierarchical model to determine the number of breeding groups at the regional scale, and obtain the error of the estimate. The methodology allows homogenizing wolf monitoring between the different autonomous communities and obtaining comparable and replicable estimates at the national level. Likewise, it can be applied to other species of large carnivores or used for those where the young are difficult to detect. "Its applicability at the regional level is important, and how it can be extended to multiannual studies, and using covariates, to study how various factors or human activities affect not only the presence of the species, but also reproduction or its expansion," he adds. Jimenez Garcia.

    Bibliographic reference:

    José Jiménez, Emilio Garcia, Luis Llaneza, Vicente Palacios, Jaime Muñoz, Luis Mariano González, Francisco García Domínguez and José Vicente López-Bao. Multi-method and multi-state Bayesian hierarchical site occupancy models to survey large carnivores: Estimating wolf reproductions at regional scales. Conservation biology. DOI: 10.1111/cobi.12685