Using citizen‐reported data to predict distributions of two non‐native insect species in Sweden

Abstract

Abstract. Information on exotic species' current and potential distribution is vital for decisions on management. Species distribution models can predict where colonizations are likely; however, the collection of species' distribution data over large areas in order to parameterize the models is costly. Therefore, modelling methods that are able to use low-cost information such as citizen-reported data are potentially very useful. In this study, we used the species habitat modelling program Maxent to predict the potential geographical distribution of two non-native insect species in Sweden, the butterfly Araschnia levana and the shield bug Graphosoma lineatum. For this we used citizen-reported presence-only open-access data in combination with climate and land cover data from national databases. Our models showed that presence of A. levana was best predicted by winter temperature and habitats related to open grasslands. For G. lineatum, summer temperature and open green areas, in both urban and rural areas were the best predictors for species presence. These models show that large areas of non-colonized potential habitats exist within Sweden. For A. levana these yet-to-be-colonized habitats are mainly in the south, while for G. lineatum these habitats occur in the south and along the Baltic Sea coast. Comparisons of temporal patterns in species reporting for A. levana and G. lineatum to similar insects with known stable populations revealed large 'willingness to report' effects that could potentially bias range expansion rates. Once corrected for, current distribution expansion rates were estimated as 1.9 km/yr and 1.07 km/yr respectively. The study shows the use of public reports in conservation science as a way of gathering species information over large areas. This increases the data sources available for researchers to predict the distribution of species and have the additional value of the involvement of the public in conservation efforts.

Linee Guida per il monitoraggio dei coleotteri saproxilici protetti in Europa

“…Infatti, la qualità dei dati raccolti dai volontari è risultata comparabile con l'insieme dei dati raccolti in precedenza dagli specialisti. Ancora, Widenfalk et al (2014) dimostrano come i dati della CS rappresentano un valido strumento per gli studi ecologici e faunistici.…”

“…Tuttavia, il progetto MIPP rappresenta un programma di verified citizen science (Gardiner et al 2012), in quanto la validazione scientifica dei dati è assicurata da un gruppo di specialisti che esaminano le fotografie trasmesse dai cittadini. I dati raccolti dai cittadini rappresentano un validissimo strumento per studi di taglio ecologico e faunistico sulla distribuzione di insetti (Widenfalk et al 2014). Ad esempio Zapponi et al (2017) hanno dimostrato come set di dati ottenuti in due soli anni dai cittadini in uno studio svolto Italia, abbia incrementato a livello nazionale le conoscenze distributive di almeno tre specie di insetti in maniera maggiore rispetto a quelle ottenute con i dati raccolti unicamente da esperti.…”

Analyses of occurrence data of protected insect species collected by citizens in Italy

“…Using a subset of the dataset analysed here (2 years, 3 species), the authors demonstrated the high value of this CS initiative, as the quality of occurrence data gathered by volunteers was similar to the data collected exclusively by experts. In addition, Widenfalk et al (2014) emphasised that data collected by citizens represent an extremely valuable instrument for studies on ecology and distribution. It is believed that CS can not only provide collections of valid data, but also represents a positive way to connect people with nature and this can increase the collective knowledge on conservation values and threats for the environment (Devictor et al 2010).…”

“…The CS approach has been applied for insect monitoring in a great number of projects with a wide range of geographical scales, for example: -Urban: butterflies monitoring in the cities of Chicago, New York and Tokyo (Matteson et al 2012, Washitani et al 2013; Invasive Alien Bumblebee in Hokkaido (Kadoya et al 2009). -National: butterfly monitoring in Germany (http://www.science4you.org), Ireland (Donnelly et al 2014) and Malaysia (Wilson et al 2015); anglers monitoring initiative of UK (http://www.riverflies.org); UK Ladybird Survey (UKLS; http:// www.ladybird-survey.org); insect monitoring in South Africa (Lovell et al 2009); Swedish Species Observations System (http://www.artportalen.se).…”

“…Moreover, MIPP is a "verified citizen science" programme (Gardiner et al 2012), as validation of data is ensured by specialists. Data collected by citizens is an extremely valuable instrument for studies on ecology and distribution of insects (Widenfalk et al 2014). For example, Zapponi et al (2017) found that the dataset obtained in two years by citizens resulted in an increase in the distributional ranges of three beetle species, compared with a national inventory provided by experts.…”