Avtekologija in ogroženost strašničinega mravljiščarja Phengaris teleius (Lepidoptera: Lycaenidae) na Ljubljanskem barju

Močilar, Mitja (author), Verovnik, Rudi (mentor), Jerina, Klemen (comentor)

V naši raziskavi smo preučevali avtekologijo strašničinega mravljiščarja (Phengaris teleius) na zahodnem delu Ljubljanskega barja. Zanimalo nas je trenutno stanje populacije metulja na preučevanem območju, vpliv poplav leta 2010, 2013 in 2017 na razširjenost gostiteljske vrste mravlje ter vplivi rabe sosednjih zemljišč (košnja, višina vegetacije in listnega opada) na prisotnost strašničinega mravljiščarja in gostiteljskih vrst mravelj rodu Myrmica. Z metodo lova in ponovnega ulova MRR in postopkom CLM smo določili skupno velikost populacije strašničinega mravljiščarja, tj. 322 osebkov. To nakazuje na trend ponovnega povečevanja populacije po velikem padcu številčnosti med leti 2008 in 2012. Z določitvijo območja in trajanja vsake od daljših poplav ter s preverjanjem prisotnosti mravelj na 160 lokacijah, smo s splošnim linearnim mešanima modelom GLMM, v katerem sta bili razlagalni spremenljivki trajanje poplave in razdalja do najbližjega refugija, lahko z 79 % verjetnostjo predvideli prisotnost mravelj. Prisotnost mravelj je negativno korelirala s spremenljivkama trajanje poplavljenosti in razdalja do najbližjega refugija. S pomočjo smernih koeficientov smo določili tudi hitrost ponovnega naseljevanja mravelj na malo manj kot 30 metrov na leto. Vpliva rabe sosednjih zemljišč (zaraščanja z olesenelimi in invazivnimi vrstami rastlin, višine vegetacije in listnega opada) na prisotnost mravelj Myrmica in strašničinega mravljiščarja nismo zaznali. Ugotovili pa smo, da prisotnost strašničinega mravljiščarja pozitivno korelira z gostoto strašnice, deležem pokritosti travnika s strašnico ter s prisotnostjo gostiteljske vrste mravelj Myrmica, ter zaznali statistično značilno negativno korelacijo s košnjo v obdobju letanja metuljev. Delež vpliva posameznih dejavnikov smo ugotavljali z regresijskim drevesom in najustreznejšim GLM. Oba kažeta na košnjo kot dejavnik z največjim vplivom, sledi ji prisotnost mravelj, nato gostota strašnice in nazadnje delež pokritosti habitatne krpe s strašnico. Z rezultati naše raziskave smo poglobili razumevanje avtekologije strašničinega mravljiščarja, s čimer lahko nadgradimo že obstoječe smernice varovanja vrste, ki zagotavljajo večjo verjetnost njegovega preživetja v Sloveniji in svetu.

• Language: Slovenian
• Keywords: poplave, upad, mirmekofilija, Slovenija, izginjanje, kolonizacija, prostorska dinamika
• Work type: Doctoral dissertation
• Typology: 2.08 - Doctoral Dissertation
• Organization: BF - Biotechnical Faculty
• Publisher: [M. Močilar]
• Year: 2025
• PID: 20.500.12556/RUL-175968
• UDC: 595.78:504.4(497.451.1 Ljubljansko barje)(043.3)
• COBISS.SI-ID: 257419779
• Publication date in RUL: 15.11.2025

Secondary language

• Language: English
• Title: Autecology and endangerment of scarce large blue Phengaris teleius (Lepidoptera: Lycaenidae) in Ljubljansko barje

Abstract

We studied the autecology of the Scarce large blue (Phengaris teleius) in the western part of the Ljubljansko barje. We were interested in the current state of the butterfly population in the studied area, the impact of the floods in 2010, 2013, and 2017 on the distribution of the host ant species, and the effects of neighbouring land use, mowing, vegetation height, and leaf fall on the presence of the Scarce large blue and the host species of the Myrmica ant genus. Using mark-recapture (MRR) and the chain ladder method (CLM), we estimated the total population size of the Scarce large blue at 322 individuals. This indicates a trend of population recovery after a significant decline between 2008 and 2012. By determining the extent and duration of each of the major floods and checking for ant presence at 160 locations, we built generalized linear mixed model (GLMM) using duration of flooding and the distance to the nearest refuge as predictors, which predicted presence of ant with a 79 % probability. The presence of ants showed a negative correlation with the duration of flooding and the distance to the nearest refuge. Using directional coefficients, we also estimated the rate of ant recolonization to be just under 30 meters per year. We did not detect any influence of neighbouring land use, encroachment by woody and invasive species, or vegetation height and leaf fall on the presence of Myrmica ants and the Scarce large blue. However, we found that the presence of the butterfly positively correlates with the density of the host plant, the proportion of the meadow covered by the host plant, and the presence of the host ant species Myrmica, while there was a statistically significant negative correlation with mowing during the butterfly flight period. We assessed the relative impact of individual factors using regression trees and the most appropriate GLM. Both models identify mowing as the factor with the greatest influence, followed by the presence of ants, then the density of the host plant, and finally the proportion of habitat area covered by the host plant. The results of our research enhance the understanding of the autecology of the Scarce large blue, which can be used to improve existing conservation guidelines that ensure a higher likelihood of its survival in Slovenia and worldwide.

• Keywords: flooding, decline, myrmecophily, Slovenia, eradication, colonization, spatial dinamics