The Great Crested Newt eDNA Testing Season runs between the 15th April and the 30th June each year. This means water samples must be collected between these dates because that is when there is sufficient Great Crested Newt DNA in the water.
Great Crested Newts breed in ponds between February and June, and their activity leaves traces of their DNA (for example shed from their skin, faeces, mucus and eggs). These traces of DNA can persist in the water for several weeks, allowing its presence to be tested in water samples taken from the pond or body of water.
Outside of these months, the newts have finished breeding and will have left the pond until the following year’s breeding season starts. DNA degrades and the rate at which this occurs can be sped up by UV radiation, temperature and microbes that occur in the pond. This means it is likely there wouldn’t be sufficient eDNA remaining in the water to confirm the presence of Great Crested Newts.
If a water sample is taken outside of the season, negative eDNA results cannot be used to support the absence of Great Crested Newts.