The presence of protected or notable habitats or species on a proposed development site can be a major constraint to a project. To avoid possible costly delays to the development works programme and alterations to design plans we recommend expert advice from a specialist ecological consultant is sought at the earliest opportunity and ecological surveys carried out early on in the development process. Ideally, as soon as a site is acquired (or before, if possible), then ecological surveys should begin, so that potential ecological issues can be raised at the earliest opportunity and any further Phase-2 ecological surveys can be planned and mitigation and compensation measures designed into the development site layout.
Most ecological surveys are best carried out at certain times of year and some can only be carried out at specific times. The Ecological Surveys Timetable below shows the optimal (and sub-optimal) times to aid in the planning of ecological surveys. However, it should be noted that there can be seasonal variations from year to year, when in some years the statutory agencies will allow surveys to start sooner or finish later in the year depending on for example un-seasonally warm periods.
The Ecological Surveys Timetable is a guide only and expert advice from a specialist ecological consultant should be sought to plan a survey programme in detail.
Ecological Surveys Timetable
Habitat and Botanical Surveys
Ecological Surveys | Optimal Time | Comment |
Phase-1 habitat | April – Sept | Possible to survey Oct – March but sub-optimal |
Extended Phase-1 habitat | April – Sept | Possible to survey Oct – March but sub-optimal |
Ecological walk-over | April – Sept | Possible to survey Oct – March but sub-optimal |
Hedgerow | April – June | Hedgerow ground flora is more evident at this time Possible to survey July – March but sub-optimal |
Botanical (higher p.): Grassland Woodland |
May – July April – June |
Possible to survey (Apr/Aug/Sept) but sub-optimal Woodland ground flora is more evident at this time |
Japanese knotweed | Jan – Dec | The stems persist over the winter |
Protected Species Surveys
Ecological Surveys | Optimal Time | Comment |
Badger |
Nov – April |
Possible to survey May – Oct but sub-optimal |
Bats: Scoping/ roosting Activity/emergence/dawn |
Jan – Dec May – Sept |
Oct – Apr sub-optimal Possible to survey April & Oct but sub-optimal |
Birds: Breeding birds Wintering birds |
March – June Nov – Feb |
Possible to survey in July but sub-optimal Can only be carried out at this time of year |
Great crested newt: Breeding ponds |
Mid – March to mid – June |
Can only be carried out at this time of year |
Hazel dormouse | April – Nov | Can only be carried out at this time of year |
Otter | Jan – Dec | Can be carried out at any time of year |
Reptiles | April, May & Sept | Possible to survey in June, July & Aug but sub-optimal |
Water vole | March – Oct | Possible to survey Nov – Feb but sub-optimal |
White-clawed crayfish | July – Oct | May and June should be avoided as young are released |