Closer to Carrying Capacity: Analysis of the Internal Demographic Structure Associated with the Management and Density Dependence of a Controlled Wolf Population in Latvia

Abstract

Large carnivores are essential components of natural ecosystems. In populated areas, their conservation depends on preserving a favorable status in coexistence with humans, which may require the elimination of excess carnivores to minimize public concerns. As the Baltic region currently hosts a thriving wolf population, locally sustainable management of wolves is important for preserving biodiversity at a European scale. In this paper, we provide a dynamic assessment of the Latvian wolf subpopulation from 1998 until 2020. This study is based on age composition and fecundity data from teeth, uteri, and ovaria inspections obtained from samples of legally culled or accidentally killed individuals. The abundance estimates indicated population growth that exceeded the previously predicted carrying capacity. The proportion of juveniles among the culled individuals increased in recent years, but the mean age of culled adults exhibited a stable trend. In presumably nonselective hunting, the juveniles and individuals older than 3 years had greater culling mortality estimates in comparison with other age classes, and the culling rates for adult females of particular age classes were higher than for males of the same age. While creating significant hunting pressure, wolf management in Latvia may have contributed to the population growth by affecting its demographic processes.

Does Wolf Management in Latvia Decrease Livestock Depredation? – An Analysis of Available Data

“…No correlation was found between sheep depredation and estimated numbers of most prey species. Although the numbers of roe deer and wild boar in Latvia have fluctuated [15,25,44], there is no reason to assume significant shortage at any point. However, cumulative number of affected sheep was related to estimated numbers of red deer, and according to estimated coefficients more affected sheep were expected at higher red deer densities.…”

“…The study area, wolf management and routine sampling of culled individuals in Latvia is described in more detail by Šuba et al [25]. Wolves are distributed throughout the whole country.…”

“…The quota has been increased since its introduction and for the last decade it has been around 270-300 wolves per hunting season. In Latvia, the hunting pressure is considered to be rather high and harvest mortality was estimated to be around 37% in last two decades [25]. Main prey species for wolves are roe deer (Capreolus capreolus) and wild boar (Sus scrofa) and to a lesser extent red deer (Cervus elaphus) and Eurasian beaver (Castor fiber) [15,26].…”

“…The calculated number of sheep per km² was referred to all the forestry units within the array. Data on wolf age structure from 2004 until 2021 were obtained by the authors from examined legally culled individuals and otherwise found carcasses (see Šuba et al [25] for more details). Teeth samples for age assessment were prepared according to methods described by Klevezal [31].…”

Genetic Monitoring of Grey Wolves in Latvia Shows Adverse Reproductive and Social Consequences of Hunting

“…In 2000, the development of the first wolf species conservation plan was started in Latvia [ 28 ], and since 2004, an annual quota has been set and a wolf hunting season has been established. After the introduction of restrictions, the number of wolves in the population gradually increased [ 29 , 30 ]. The goal of the protection and management of the species in Latvia, according to the current conservation plan, is to preserve the favourable conservation status of the grey wolf population for an unlimited period of time and to promote the maintenance of this status [ 29 ].…”