Locomotor activity of two sympatric slugs: implications for the invasion success of terrestrial invertebrates

Abstract

Abstract. A central focus of invasion biology is to identify the traits that predict which introduced species will become invasive. Behavioral traits related to locomotor activity most likely play a pivotal role in determining a species' invasion success but have rarely been studied, particularly in terrestrial invertebrates. Here, we experimentally investigated the small-scale locomotor activity of two slug species with divergent invasion success in Europe, the highly invasive slug, Arion lusitanicus, and the closely related, non-invasive and native slug, Arion rufus. To do so, we used a multi-state capture-mark-recapture approach, and hypothesized that the invasive slug has a higher moving rate (keeps on moving) and leaving rate (leaves more frequently known places). A total of 221 invasive and 241 non-invasive slugs were individually marked using magnetic transponders and released in three study sites differing in habitat type. The slugs were recaptured using shelter traps, and moving and leaving rates were estimated. Both rates were significantly higher for the invasive slug, demonstrating a higher locomotor activity which might partly explain its invasion success. Our results provide evidence for the recently suggested idea that locomotor activity might be an important trait underlying animal invasions using for the first time terrestrial invertebrates.

Introgressive replacement of natives by invading Arion pest slugs

“…Invasive species are often considered competitively dominant: they might use food resources more rapidly and/or efficiently than native species 52 , exhibit rapid adaptation and spread 53 , faster growth rates 54 and higher reproductive output 55 . Indeed, A. vulgaris seems to be able to use food resources more efficiently than native species 56 , 57 , and shows a more pronounced exploratory behaviour in novel environments 58 , 59 . Further, A. vulgaris seems to be able to cope with land use change and agricultural intensification better than the native species 60 .…”

Intraspecific Variation among Social Insect Colonies: Persistent Regional and Colony-Level Differences in Fire Ant Foraging Behavior

“…It would be extremely interesting to test fire ant colony behavior patterns along an invasion gradient. Recent studies have hypothesized that behavioral syndromes, particularly those geared toward higher activity and aggression, may contribute to invasive success [ 76 – 79 ]. Comparisons across native and invasive range may help to clarify the role of evolution and changing environment in the success of invasions and the evolution of collective behavior.…”

The role of invertebrates in seedling establishment in a heterocarpic plant, Atriplex sagittata

“…Like other slugs (Fenner et al, ), A. vulgaris is an efficient seedling herbivore (Honek et al, ) and might change the composition and decrease the diversity of herb communities (Fabian et al, ). This species exhibits superior mobility (Honek & Martinkova, ; Knop et al, ) and is well adapted to warm and dry microclimates (Knop & Reusser, ); consequently, it survives well on farmland (Ryser et al, ). The presence of populations of this slug on degraded areas (construction sites, roadside margins) that are typical A. sagittata habitats is supplied by emigrants from near grassy sites (Honek & Martinkova, ) and might be favoured due to an impoverishment of the soil fauna (Zaller et al, ).…”