How many of them? Genetic diversity, survival and effective population size of the capercaillie population from the Gorce Mountains

Abstract

Population size and effective population size are important factors affecting probability of extinction of small, isolated population. Hence, from conservation perspective, it is recommended to monitor changes in population size of endangered species. Genetic methods, based on genetic profiling of non-invasive samples of biological material, despite some limitations, were proved to be efficient method in tracking individuals in the field and estimate populations' parameters. We used this strategy to investigate isolated population of the capercaillie (Tetrao urogallus) in the Gorce Mountains. In two study periods (2012–2013 and 2017–2018) almost 400 faeces and feathers were collected. Microsatellite genotyping was performed to identify individuals and estimate genetic diversity. We found that population is stable in terms of size and genetic indices, although allelic richness has significantly increased between 2012–2013 and 2017–2018. In the overall study period (2012–2018) there were 52 individuals identified. However, only 10 birds were found in both study periods. This suggests low survival in the population. Moreover, genetic data indicated low effective population size of the capercaillie in the Gorce Mts. Thus, we suggest that monitoring, either genetic and based on field-surveys, should be implemented in the management and protection of this population.

Genetic diversity of the Carpathian capercaillie in space and time

“…The Brookfiled (1996) method did not indicate the significant frequency (>2%) of null alleles at the examined loci, which is consistent with previous publications based on this panel of microsatellite markers (e.g. Rutkowski et al 2017a;Szczepański et al 2019).…”

“…Capercaillie numbers in this area were very low in the 1970s and 1980s, before demographically stabilizing at the end of the 20th century -the presence of 25 to 30 individuals per year was detected there (Żurek and Armatys 2011;Zawadzka 2014). However, in the second decade of XXI century, using various methods, including genetic ones, 30-40 individuals were identified annually (Rutkowski et al 2017b;Szczepański et al 2019;Zawadzka et al 2019).…”

“…The genotyping analyses were performed using a CEQ 8000 sequencer (BECK-MAN COULTER). To obtain reliable genetic data, several measures were taken to avoid genotyping errors, as described in Szczepański et al (2019).…”

“…Moreover, data indicating a stable or even increasing population trend in the Polish part of the Carpathians may be illusory, as previous estimates were based on a methodology generating significant errors (Zawadzka et al 2019). In addition, genetic research -identification of unique genotypes in non-invasive samples -suggests that at least in some Carpathian refuges, the number of identified individuals is gradually decreasing (Santorek et al 2018(Santorek et al , 2020Szczepański et al 2019). It is therefore generally unknown to what extent genetic changes are taking place in the Polish population of the capercaillie in the Carpathians, especially in terms of gene flow between strongholds.…”

Relationship between semen quality and level of heterozygosity on the model of endangered population of Western capercaillie

“…In order to prevent the further decline in capercaillie population, in 2002 Polish authorities decided to establish two ‘Capercaillie Breeding Centres’ whose main objective is to obtain birds for further restitution or reintroduction, and to intensify their active protection by breeding ex situ in vivo. At the same time, several reintroduction programmes were implemented along with genetic and ecological research concerning wild and reintroduced populations (Kobielski et al, 2013; Merta et al, 2013a, 2013b, 2016; Rutkowski et al, 2005; Rutkowski, Zawadzka, Merta, et al, 2017; Rutkowski, Zawadzka, Suchecka, & Merta, 2017; Strzała et al, 2015; Szczepański et al, 2019).…”