Seasonal variation in the body weight of the invasive slug Arion vulgaris (Gastropoda) in Central Finland
Year: 2026
Type: article
Abstract: The Spanish slug (Arion vulgaris Moquin-Tandon, 1855) has been designated as a nationally harmful invasive species in Finland. This study investigated seasonal variation in the mean fresh body weight of A. vulgaris from spring to autumn at a single location in Central Finland. The mean body weight of Arion vulgaris increased fairly linearly by about 9 grams from late May to late August, reaching a maximum of 22 grams. The variation in body weight was smallest in May–June and largest in July–August; the September weight was similar to that of August. The results support observations from Scandinavia and Central Europe that A. vulgaris mainly overwinters as either eggs or juveniles. A smaller, snapshot sample of the black slug Arion ater (Linnaeus, 1758) in September suggests that the species attains a larger body size than A. vulgaris. Because granular baiting was used to control slugs at both study locations, additional data from unmanaged populations are required to assess the extent to which observed patterns in body weight reflect management effects.
Author: Komonen, Atte
Language: English
Subfield: Insect Science
Domain: Life Sciences
SDG: Life on land
Open Access status: diamond
OpenAlex ID: W7224692745