Otters and their homes, known as holts, are protected under UK and European law so it is important to know if they may be affected by work on your site. Otters can range over a wide area and may have several holts and smaller resting places. They mostly live near water as their diet is mainly small fish like freshwater eels but can be found in land areas as well.
There is legal precedent (R vs Cornwall County Council) that where a European protected species may be using a site planning permission cannot be granted until all relevant information has been provided to the planning authority. This means that not doing surveys in time can mean delays of a year or more in getting permission.
A survey of your site will identify if otters are using any rivers or streams running through it and if there are any holts on site. It will also come up with recommendations to ensure otters are not harmed during construction or use of any development on site.
If a planned development would directly destroy or damage an otter holt this could prevent work unless the proper procedures are followed – see protected species licencing and mitigation.