Browsing by Subject "Vieraslajit"

Biodiversity loss is one of the pressing challenges of the 21st century, affecting ecosystems and people around the world. One of the biggest drivers of biodiversity loss are invasive alien species (IAS). Prevention of the arrival and spreading is the most efficient management option for IAS, which requires consistent monitoring, to ensure early detection. Effective surveillance of IAS may be challenging to conduct by authorities and professionals alone, and alternative data sources are needed to gather up-to-date data on species distributions. Novel data gathering tools and research approaches can provide easily available digital data for researchers to use. One of these options is citizen science (CS), where citizens are participating in scientific research. CS provides a cost-effective way to gather species observations in wide geographical and temporal scales. Citizen observations of IAS are seen as a valuable data source to support professional monitoring and they have been increasingly utilized in IAS research in recent years. The aim of my thesis was to study what kind of information have citizens produced on IAS in Finland. I studied the spatial and temporal distributions, as well as the taxonomic component of citizen observations of IAS, in the Finnish Biodiversity Info Facility’s open access database. Spatial distribution of the observations was visualized in choropleth maps and the spatial clustering of the data was studied with Moran's I, kernel density estimations and standard deviational ellipses. Additionally, I studied if there were IAS observations from the Finnish Natura 2000-sites as protected areas have been noted to be vulnerable to invasions. These data were also compared to expert observations (research projects, ecological surveys), to see differences between the datasets. Results showed that citizens had observed over 30 IAS in Finland and the majority of observations (52.77%) were made in recent years (2020–2023). Observations came from all regions of Finland, with high concentrations on the southern part of the country and around highly populated municipalities. Comparisons to expert observations suggested that citizens could provide complementary information on species less observed by experts and geographically in the northern part of the country. IAS monitoring in Finland can therefore benefit from citizen observations to fill in gaps in species distributions. The citizen observations did, however, include certain limitations and biases that need to be taken into account in further research. The methods used in this study can be repeated and used to inform decisions on where to implement management actions for IAS.