Tønnessen, M. (2009). Umwelt transitions: Uexküll and environmental change. Biosemiotics, 2(1), 47–64.Tønnessen, M. (2014). Umwelt trajectories. Semiotica, 198, 159–180.
are cited in
Timo Maran 2015. Emergence of the “Howling Foxes”: A Semiotic Analysis of Initial Interpretations of the Golden Jackal (Canis aureus) in Estonia. Biosemiotics. Published online June 3rd 2015 (DOI 10.1007/s12304-015-9244-1).
There are some semiotic studies that could be used as a point of departure for a semiotic analysis of non-native or invasive species. [...] Morten Tønnessen (2009; 2014) has developed Uexküll’s Umwelt theory towards a research method for analyzing phenomenological and semiotic aspects of changing human-animal relations (e.g. between man and wolf).