Essex Ecology Services Ltd. (EECOS)
Protected Species Survey Calendar 2016
Essex Ecology Services Ltd
Our ‘Preliminary Ecological Appraisal’ (Phase 1 survey), is the best first port of call; this can be carried out now and will quickly reveal whether or not surveys for reptiles, Great Crested Newts, bats and other legally protected species are required so that these can either be ruled out or scheduled, in good time to avoid any delays to your project.
1) Great Crested Newts
Survey: March – June, With half of the visits needed mid-April to mid-May. EECOS now provides eDNA testing of pond water samples; this is a less intensive and cheaper alternative to conventional trap and torch surveys although there are time constraints. Contact EECOS for further information. During early spring male Great Crested Newts develop crests and begin courtship behaviour within their chosen breeding pond. Males display to females with tail and crest waving and back arching, and can be aggressive to other males; a successful display sees a female passing over and receiving deposited spermatophore, thereafter laying 100s eggs, each carefully wrapped within a folded leaf.
2) Reptiles
Survey: March – June.
This is the optimal survey period although late summer/autumn surveys may be possible. Suitable areas of scrub and grassland are covered in felt survey mats, which need 1-2 weeks to ‘bed in’.
The best time to see Adders is during early spring when they emerge from hibernation dens and males can be seen writhing together in competition for females, during what is described as the ‘dance of the Adders’. During April, males shed their dull winter skin in preparation to mate.
3) Breeding birds
Survey: End of March – early June; 4-6 early morning visits are needed, depending on habitat complexity, to assess species diversity and abundance using territory mapping.
Blackbirds are amongst the earliest species to nest, resulting in a long breeding season from early March to late July, enabling them to have up to four separate broods. Incubation takes two weeks and the normal clutch size is 3-5 eggs.
4) Water Voles
Survey: April – May (optimal time)
; later surveys are usually possible up to September.
Water Voles start breeding during early spring once temperatures increase; young are born between April and September following a short gestation period of three weeks. An adult female can have 3-4 litters a year and young voles are weaned at two weeks.
5) Dormice
Survey: starting April – May
; nest tubes are set out during this time to determine presence or likely absence of Dormice within suitable woodland, scrub and hedgerows, with final results available in November.
Dormice hibernate from October to late April, reducing their breathing and heart rate by 90% and surviving on their fat reserves. They emerge from their nest (at or below ground) when temperatures rise, coinciding with the arrival of Hawthorn, Elder and Dogwood flowers, which represent an early food source.
6) Invertebrates
Survey: April – September,
with a good spread of visits to catch various invertebrate flight and activity periods within favourable habitat e.g. brownfield sites and habitat mosaics.
Many invertebrates that have overwintered as adults become active during March/April, including bugs, spiders, ladybirds, hoverflies and nymphalid butterflies such as Peacock. Oil beetle adults emerge, completing one of the most fascinating lifecycles of any of our insects, their larvae being reliant on a solitary mining bee:
7) Bats
Survey: May – Septembe
r; visits during May and June are required in order to coincide with the start of the maternity roost period. Initial assessments of trees or buildings affected by works can be carried out now and through the year.
Bats have now emerged from hibernation, being hungry and active – although they become torpid during periodic cold/wet weather. This time of year, females begin to form maternity colonies in buildings or trees whilst males roost alone or in small groups.
8) White-clawed Crayfish
Survey: July – October.
Some initial surveys are possible during April.
Female White-clawed Crayfish are still developing their eggs during spring, before the live young hatch and are released during May/June – this being the most sensitive time of year for females, as a defensive tail-flick can release young hatchlings before they are fully developed.
9) Badgers
Survey: All year round.
The ideal time to survey, however, is early spring and late autumn when there is less vegetation to hide the field signs of Badgers, including setts, latrines and prints. Mating takes place during early spring and late summer, during which males are increasingly aggressive; delayed implantation means that blastocysts (very early embryos) implant in late December / early January. This means that most births occur during early February, with litters generally composed of 2-3 young. New born cubs emerge after 8 to 10 weeks, usually in late April or early May.
10) Otters
Survey: All year round.
Periods of high rainfall and flooding impede surveys as Otter spraints and footprints can be washed away during high flows.
Otters start breeding when they are two years old, when they have 1-2 cubs in a litter. There is no breeding season as such as they can breed through the year, although seasonal breeding during spring has been observed. During spring food shortages, Otters supplement their fish-based diet with crayfish, amphibians and – occasionally – mammals and birds.
All of the profit made by EECOS is given to Essex Wildlife Trust
to support its important conservation work.