Williams Homes (Bala) Ltd. needed ecological survey and mitigation support for Trem Y Moelwyn, a development of just over 40 affordable homes in Penrhyndeudraeth, Gwynedd, on a small field bordered by housing, a main road, a mature tree line and a dry stone wall. Initial survey work uncovered a live slow worm population protected under the Wildlife and Countryside Act 1981, alongside Natural Resources Wales (NRW) concerns about bats using the northern tree line, and Japanese knotweed on site, all of which needed resolving before the scheme could go to planning.