Effects of free-ranging cattle and landscape on bats in high mountain environment
2019
Autori:
Ancillotto, LeonardoFesta, Francesca
De Benedetta, Francesca
Consentino, Francesca
Bajić, Branka
Russo, Danilo
Tip dokumenta:
Konferencijski prilog (Objavljena verzija)
,
©2019 Associazione Teriologica Italiana onlus
Metapodaci
Prikaz svih podataka o dokumentuApstrakt:
Intensive agricultural system and livestock farms have replaced
primary forest, which implies an impoverishment of biological
communities. Where livestock is managed as free ranging at
low or medium grazing intensities, however, this may prove
beneficial to biodiversity because it favours the occurrence of
spatial and trophic resources for wildlife.
Foraging and commuting by insectivorous bats are affected by
both insect availability and habitat / landscape structure, which
in turn may be affected by the presence of cattle. Previous work
showed a positive relationship between the presence of cattle and
their dung and bat activity at low elevation. Therefore, we hypothesized that the same relationship would occur in mountainous
landscape of Central Italy. We set our study at the Abruzzo,
Lazio and Molise National Park.
We surveyed bat activity using Pettersson D1000x bat detectors
for 4 hours since sunset in June-August 2017. The 15 sampling
sites where located between 900 and 1520 m a.s.l. and each site
was sampled three times, each time with a different treatment
according to cattle condition: cattle and dung present; dung,
but not cattle, present; both cattle and dung absent. Landscape
structure at each sampling sites was quantified as the amount
of forest area and the distance to, and length of the nearest
forest edge within “landscapes” of different size, i.e. circles
characterized by a radius of 50, 100 and 300 m around each
sampling site. The analysis was carried out with QGis (LecoS
plugin).
To analyse the response of bat activity and richness to the above described factors, we used generalized linear mixed models (GLMM) at the three spatial scales considered; a Tukey
Post-Hoc test was carried out for factors that proved significant.
Bats responded in a species-specific way to the three treatments
as well as landscape structure. Total bat activity was, at all
landscape scales considered, positively influenced by the amount
of forest cover and proximity to forest edge. This result can
be explained considering that bats exploited the forest both for
foraging and for commuting.
Hypsugo savii activity was affected by the amount of edge habitat, yet this had a significant effect only within 100 m from the
sampling site. Pipistrellus kuhlii and P. pipistrellus increased
activity where forest was more abundant, at the scales of 100
and 300 m, and that of P. kuhlii decreased at higher altitudes
unless the other species present in the area. Out of all species
considered, only P. pipistrellus preferred site where cattle were
present. Cattle herds probably act as landmarks, attracting bats
which may thus exploit the swarms of blood-sucking insects that
often feed on cattle. Our study confirms the important relationship existing between free-ranging livestock and bat foraging
behaviour, at least for opportunistic bat species that feed on small
dipterans and forage in open space or along forest edges.
U:
- IV convegno italiano sui chirotteri; 2019 Oct 17-19; Padova, Italy. Gruppo Italiano Ricerca Chirotteri – Associazione Teriologica Italiana; 2019. p. 37.