By offering the creatures something shiny to eat, one hopes that the shine will come out the other end and provide answers about how many water voles there are and where they reside.
Rob Parry, head of Initiative for Nature Conservation Cymru (INCC), explains that they have been in contact with veterinarians to ensure that the shine, the edible type used for cakes, is not harmful to water voles.
It's a method we have used before with other species, especially badgers, where we mix with peanuts, which badgers love.
The shine is placed on apple pieces, which do not belong to water voles' natural food, yet they gladly eat them.
Different colors can be used to localize different families. If one succeeds in tracking the animals, one can then make adjustments to the environment, such as removing invasive coniferous trees or fencing off riverbanks to prevent them from grazing.
Water voles have been severely affected when wetlands have been drained and minks released from enclosures saw them as perfect prey.
The water voles had no chance, really, says Rob Parry.
What do you think?