Nutria and muskrats are the most widespread non-native invasive rodents in Europe. Their presence has a negative impact on both the natural and built environment. Their burrows increase erosion, damage flood defences, alter the ecology of wetlands, displace native species, destroy crops and increase the risk of flooding and disease. To prevent this damage, Belgian, Dutch and German partners have implemented the MICA project under the LIFE programme. The initiative is led by the Dutch Water Authority, but various sectors (e.g. universities, research centres, authorities, chambers) are also involved in the cooperation.
The partners worked together in the Natura 2000 areas of the three countries to detect and eliminate these invasive rodents, developing and deploying new and innovative methods and technologies. These methods are as follows:
- Camera tracking: Installation of smart (artificially intelligent) wildlife cameras. The devices are triggered by waves caused by the animals swimming. Thanks to a built-in algorithm, the camera is able to distinguish between the rodents being monitored and other animals. Image recognition software reduces the number of recordings that need to be reviewed manually. The camera system can be used to confirm the presence of invasive species in the area.
- E-DNA: Since the openings of the burrows of nutria and muskrats are located under water, it is difficult to map the presence of these animals. For this purpose, samples are taken from the water body and DNA testing is performed. The aim of the research is to detect body fluids or skin cells from the animals to be collected, which can be used to pinpoint the animals’ burrows and narrower habitat. The samples are collected using a semi-automatic sampling device attached to a fishing rod or boat, which also records the coordinates of the sampling. After laboratory testing, it is possible to clearly determine where the animals are most likely to be found.
- Smart traps: Once the animals’ immediate habitat has been identified, traps are set. To ensure that only the animals to be captured end up in the cage, the traps are equipped with an image recognition system. This means that the trap door only closes when the animal caught in the trap is actually one of the invasive rodents being sought. When a successful catch is made, the device sends a notification by phone to the person who set the trap.
- DNA testing: DNA is taken from the captured animals to create a genetic map of the population present in the area. This makes it possible to trace the migration routes of the animals and determine the extent of the population.
- Shared database: A shared, international map database is being created for the captured animals, which can be used to verify the effectiveness of invasive species control measures. The collected data can be registered on the platform, which facilitates cooperation between international partners.
The project has resulted in a cross-border management strategy for the control of nutria and muskrats. The technologies developed and used during the intervention serve as good practices for conservationists working in other parts of Europe.
