invaPICS – Assessing the phenological niche of invasive species using citizen science photo observations

• Applicant: Dr. Yves Philippe Klinger
• Subject Area: Ecology and Biodiversity of Plants and Ecosystems
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 560207181

Invasive species (IAS) are among the most important causes of global biodiversity loss. A crucial but understudied aspect of invasion ecology is the role of phenology in plant invasions. In the past, it has proven difficult to conduct empirical phenological studies at large geographic scales because of the need for regular simultaneous observations over several years. Photo-observations by citizen scientists have great potential to advance phenological research and can help fill spatial, temporal and taxonomic gaps in existing phenological data. The increase in publicly available photo observations and advances in computer vision via deep learning enable rapid phenological classification of large datasets. The resulting phenological observations can be used to investigate the role of phenology and its influencing factors in plant invasions. This project aims to improve the fundamental understanding of the role of phenology in plant invasion by using publicly available photo observations and state-of-the-art classification/modeling techniques. First, a workflow for the phenological classification of Citizen Science photo observations using DL is created and different model infrastructures are compared for their performance in classifying a large number of species with regard to their phenology (WP1). In the second step, invasive species are selected on the basis of previously defined characteristics and classified according to their phenology using the model developed in WP1. Based on the classified observations, we model the spatio-temporal patterns of phenological events and investigate which environmental factors drive the phenological development of the study species. Based on this, we analyze the differences between the native and invasive distribution areas with respect to the ecological niche of the study species (WP2). In the final step, the relative phenological niche of invasive species is investigated. By this, we use vegetation databases to identify species that occur in the native and invaded ranges together with the invasive species. For these species, phenological classification is carried out using the model from WP1 in order to compare the timing of key phenological events of the studied IAS to co-occurring species in both ranges. In addition, other relevant functional traits will be used to assess the phenological niche of the species studied (WP3). The knowledge gained in the project can add considerable value to the research fields of phenology and biological invasions and lead to a better understanding of plant invasions.

• DFG Programme: Research Grants
• International Connection: Italy, Sweden
• Cooperation Partners: Professor Dr. Rolf Lutz Eckstein; Dr. Vanessa Lozano
• Co-Investigators: Professor Dr. Till Kleinebecker; Dr. Erik Welk