Going Beyond ‘Non-Human’: Exploring the Diversity of Urban Species through a Nature Observation Marathon
The Nature Observation Marathon (internationally known through the BioBlitz format) is an annual event in Estonia, held at the beginning of June. This year, the marathon took place on June 7–8. During this 24-hour event, specific areas are designated for intensive nature observations, where participants ideally record all the species they encounter. The Tartu living lab (LL) team set up an observation site in the Kvissentali flooded meadow within our LL area. This important riverside greenland area along the Emajõgi river features bushland, meadow patches and wetland areas. It's one of the biodiversity hotspots in our LL region, though parts of it are slated for residential development in the coming years. A hiking trail runs along the riverbank, but it remains quite wild—lacking formal access points or developed paths for visitor comfort.
As part of the marathon, we organized two expert-led excursions—one focused on plants, the other on aquatic invertebrates, attended by 18 local people. These species groups were chosen deliberately, as they are often marginalized in discussions of the city's multispecies affordances. Typically, such studies center on vertebrate animals, while plants and invertebrates—especially those inhabiting areas unsuitable for humans—tend to be overlooked.
For decades, both psychologists and biologists have discussed the phenomenon of plant blindness: the human tendency to perceive plants merely as background, rather than as living beings with their own needs and ways of life. Hence, during the walk we were guided to notice small differences in the morphologies and habitat needs of different plant species. During our plant walk, we identified more than 100 species, including both local flora and introduced and naturalized ones. Participants shared personal experiences and traditional knowledge about various plant uses—for instance, the use of Symphytum officinale (comfrey) to treat joint pain. This plant is also highly valued by pollinators (see picture). As noted by one of our guides and LL member, Kalevi Kull, the area was particularly notable for its diversity of willow trees. This provided a unique opportunity to observe the variation in leaf shapes and growth forms within a single genus, all coexisting in a relatively small area.
Water invertebrates are a group of animals that humans rarely encounter, making them especially worth exploring and highlighting. Understanding their specific needs in a given area helps include even those species that are neither charismatic nor commonly visible in the multispecies picture. Most of the 28 invertebrate species we found were in a ditch running through the area, including several species of water snails, aquatic bugs, Phryganea larvae, and even a fish fry of northern pike. So, a charismatic vertebrate still made its way into our exploration of the often unnoticed aquatic life.
The presence of such invertebrate diversity in a simple ditch points to a common dilemma in considering and providing multispecies affordances: changes that benefit some species can be detrimental to others. Ditches and drainage systems are a major cause of the widespread loss of wetland ecosystems and species in Estonia. While on a micro-level these ditches might create pond-like habitats for species otherwise absent from the area, this comes at the cost of losing extensive wetland habitats that are crucial for a wide range of other species.
Besides the expert-led walks, some specialists conducted independent surveys, identifying for example birds and insects. To highlight the value of species identification events: truly engaging with urban affordances requires moving beyond the broad category of ‘non-humans’ and recognizing the distinct needs of diverse life forms. After all, no other species besides humans operates with a category of ’non-human’ to make sense of their environment.
Riin Magnus
