Climate Change and Shifts in the Distribution of Moth Species in Finland, with a Focus on the Province of Kainuu

Abstract

Distributions and abundances of insect species depend on a variety of factors, but whether we focus on food plants and availability, environmental niches and shelters, predators or parasites, by far the most important limiting factor is climate. Shifts in insect community structure have successfully been correlated with glacial and inter-glacial periods (Coope 1995; Ashworth 1997; Morgan 1997), but have also attracted the attention of researchers concerned with current climate trends. Parmesan (2001) and Forester et al. (2010) examined examples from North America and Europe and emphasized that predictions of responses to a warmer climate must incorporate observations on habitat loss or alteration, land management and dispersal abilities of the species in question. For the United Kingdom, Hill et al. (2001) have summarized data on changes in the distribution of specifically three butterfly species (Pararge aegeria, Aphantopus hyperantus, and Pyronia tithonus). These authors report that the three species have been shifting northward since the 1940s and they present maps of simulated butterfly distributions for the period 2070-2099, based on the changes seen since the 1940s. According to that scenario Iceland will see some colonies of these three species in less than a hundred years. Monitoring specifically moth distributions has been less popular (Chen et al. 2009; Park et al. 2009), and especially microlepidopteran species have not received the attention they deserve, so that few detailed observations on their distribution pattrerns, covering longer periods, exist. Soderman (1994) reports that a programme to monitor moth abundance and species composition has been developed and run as a Nordic project since the middle of the 1990 s. At the moment the following countries are involved in this Moth Monitoring Scheme (MMS): Denmark, Finland, Iceland, Sweden, (at regional level), Estonia, Latvia, Lithuania and Russia (restricted to Karelia, the St.Petersburg region, and the Pskov region). The methods recommended and explained further below are meant to be used by all