Message - 7th IAL Symposium

The 7 th International Association for Lichenology Symposium 2012
(1A – O6) Submission ID: IAL0207-00001
WINNERS AND LOSERS IN ECOLOGICAL RESTORATION: EFFECTS OF NON-INDIGENOUS
HERBIVORE REMOVAL ON SAXICOLOUS LICHENS
Blanchon D. 1 , Elliott C. 1 , Ennis I. 2 , Hayward G. 1 , Galbraith M. 1 , Aguilar G. 1
1 Natural Sciences, Unitec Institute of Technology, Auckland, New Zealand
2 Research, Terranova Seeds, Auckland, New Zealand
Deer were introduced to New Zealand in the 19 th century and are now found over 70% of the country.
The impacts on native vegetation is well known, but the effects on lichens have not been widely studied. There
is only limited information available on the prevalence of lichens in the diet of deer in New Zealand, but there is
some evidence that significant quantities of fungi and lichens, including species of Pseudocyphellaria and Usnea
are eaten. Removal of introduced herbivores has a dramatic effect on the recovery of native vegetation, but it is
not known how lichens are affected. Motu Kaikoura is a 535 ha island in northern New Zealand. It was purchased
in 2004 with the aim of restoring its biodiversity. The remnant vegetation is dominated by Leptospermum and
Kunzea scrub, a result of degradation by fires, farming and browsing mammals. The effects of fallow deer (Dama
dama) have been severe, removing palatable plant species and preventing regeneration. Surveys of the vegetation
found 259 native plants species remaining, some of them restricted to sites inaccessible to deer. The lichen
flora is diverse with 92 species recorded. Saxicolous lichens are well represented as rocky substrates are common.
The eradication of fallow deer was completed in 2008, creating the opportunity to study the effects of herbivore
removal on lichen diversity and abundance. Six permanent 0.5 x 0.5 m quadrats were set up on horizontal
rock surfaces to monitor any changes to saxicolous lichens over time. The percentage cover of different lichen
species, mosses and grasses were determined in 2008 and each year after. Early results show an increase in
annual grasses within the quadrats and a decrease in percentage cover of foliose lichens, particularly Parmotrema
and Xanthoparmelia species. Fruticose lichens such as Cladia aggregata and Stereocaulon ramulosum
showed smaller decreases in percentage cover. This suggests that grasses are recolonizing after herbivore
removal and that this may be at the expense of some lichen species.
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1A-O