Helsinki Urban Rat Project is a multidisciplinary research project dedicated to understand the dynamics of urban rats and their effects on the urban life in Helsinki.

During the millennia, humans and rats have adapted to live in urban environments. The sharing of common habitat has not been without its problems. Urban rats can cause structural damage to buildings, eat foodstuffs and carry zoonotic diseases. For these natural aspects of their lives, humans have been afrad of rats and hated rats. In most developed cities, there are continuous operations against rats to try limit their population sizes and get rid of rats in wrong places from human perspective. These are costly and quite often ineffective.

From researchers point of view, rats offer an unique opportunity to do basic science. Rats live in highly controlled and well-known environments, mesocosms of one sort. We have ample amounts of biotic and abiotic spatial data on Helsinki city area, due to open data collected by the city for other purposes. This can be used to analyze how climate, weather, urban structures, urban nature or history affect the rat populations. In turn, the same data can be used to study parasite and disease spread between rats.

Rats elicit strong emotional reactions from humans. Thus they are also an interesting study subject for human-wildlife conflict. Actually, it might one the most important conflicts humans have as it is truly a global conflict which have been going on for millennia. We are also far from solving this conflict and it is surprisingly little studied. Nevertheless, the urbanization leads to more and more people living in cities, with more and more contact with urban rats.

We will use citizen science apporaches to understand rat population dynamics over the whole city of Helsinki and at the same time offer people an opportunity to reflect their relationship with rats. Citizen science is an obvious approach here, as the local residents have usually a solid understanding where the rat hotspots in each neighbourhood are. Urban nature is usually seen in positive light, while rats are seen in negative light. We will explore this conflict and how humans and rats can best cohabit the urban areas.

Urban Rat Ecology

Rats have a reputation of being dirty and disease-ridden animals. While they are substantial reservoir for pathogens and parasites in warmer regions, there is less research done in rats in boreal regions. We don't know which parasite species the rats are carrying and whether they could infect pets or humans, but our parasite surveys will at least give some idea what there is.

We are working on viral, bacterial and helminth parasites trying to first describe the community of rat symbionts and then analyze parasite dynamics in the context of spatial and temporal variation in the host populations.

This study is funded by Maj and Tor Nessling Foundation, City of Helsinki and Emil Aaltonen Foundation. Lassila & Tikanoja Oyj has sponsored a mobile laboratory for our use.

Boundless rat – a multidisciplinary study on rat movement

How many rats there are in Helsinki? How do the population sizes vary between summer and winter? Do rats in Helsinki breed around the year? How much does the coldness of winters impact rat populations? By using three distinct data sets, school student collected track plate data, pest management company generated smart trap data and sightings by trash pick-up personnel, we aim to understand the spatio-temporal dynamics of urban rat populations. These can be then combined to environmental data readily available for the urban area.

Where do the rats go during the wintertime? What kind of social lives do the rats have? Rats are notoriously difficult to monitor and their spatial use in urban areas is subsequently poorly understood. We are exploring ways how rat movement can be detected by live-trapping and marking, using wildlife cameras and by the means of population genetics.

How do rat movement is controlled? Who does decisions on rat killing? Where do the information from the "rat problem" come from? We are doing ethnographies, interviews and questionnaires on the professionals who make the network of rodent control, from the municipal authorities to the pest management professionals.

What do rats look like? What kind of emotions do they inspire? Our artists are looking ways to connect with rats and to show the nature of the urban rats through wildlife cameras, experimental photography and art installations. The lense of the camera separates but also ultimately unites rat and human and intertwines the subject and object of the art.

This study is funded by Kone Foundation.

CitiRats – Citizens with Rats

How do imagine hopeful futures with difficult urban companions? We are exploring non-anthropocentric education by giving the voice to those usually sidestepped in both science and in urban decision-making: young people and unloved species. 

We produce new knowledge and solutions with a three-tier approach, based on collaboration between researchers, young people and experts. Three progressive research stages include methods from natural sciences, human sciences and the arts. This produces new knowledge of rethinking exclusive human agency in society, of imagining multispecies futures, and of how young people best come to learn about sustainable co-living.

This project is funded by Academy of Finland and ran by Pauliina Rautio in the Univeristy of Oulu.

Cohabitation with undesired others in urban spaces – from theory to practice

Why do people feed birds? How do people make sure that the feed goes to nice animals? Urban human citizens often feed birds, as they see it a rewarding way of helping wildlife. Nevertheless, the bird-feeding often attracts urban rats to spaces, which humans have meant for birds. As humans have generally negative disposition towards rats, the bird-feeding have been prohibited in different public and private spaces. This multispecies entanglement is dynamics and in continuous flux: currently, the rat population sizes are increasing, the bird-feeding activity is decreasing and the city of Helsinki is partially removing the bird feeding prohibitions. The relationship between bird feeding and rats is also causing conflicts between humans.

We are exploring the historical context of bird feeding through feeding practices, regulations and guidelines, to understand where that specific human-wildlife conflict has emerged.

This study is funded by HELSUS – Helsinki Institute of Sustainability and HiLIFE – Helsinki Institute of Life Sciences.

Rat as a municipal resident

How do rats shape urban areas? Rats have been synanthropic species for millenia and they have travelled over the whole world with humans. Humans have a complex, yet usually difficult to notice, adaptations to keep rats in check. 

We have done questionnaires for municipal workers on their perceptions on the present and future of the rodent control. This work has been used to surveying who works with rats and how the cooperation between different stakeholders work.

This study is funded by KAKS - Kunnallisalan kehittämissäätiö.