17 species of bat are found in the UK, some of these are known to roost and feed at several of our sites. Trees are important habitats for bats, with the oldest specimens being particularly valuable roosting sites as they contain many hollows and crevices. The urban landscape also contains man-made habitats such as bridges and out-buildings, which bats often use as roosting sites.
Where a habitat with bat potential is identified, an initial assessment of the area is carried out. Urine stains and droppings are indicative of roosting or feeding bats. Clues such as these can provide detailed information about the animal, what it is using the area for and sometimes enable the species to be identified.
Emergence surveys are carried out at dawn and dusk to identify the presence of roosts. Surveys are ideally carried out at dawn when light availability is greater; in some larger roosts a swarming spectacle as the bats return can be observed. The shape and flight pattern of the bat can be used to help identify the species but the greatest tool is a bat detector and recording equipment.
At Ormesby Water Treatment Works, annual bat surveys are carried based on the methodology outlined by the National Bat Monitoring Programme. The main survey carried out at Ormesby is by boat over a duration of two hours. At set GPS points, the boat remains stationary and a bat detector recording taken for two minutes. Bats observed in between GPS points are also recorded.
Bat Conservation Trust (No date). Bat habitats. See link. Date accessed 4th May 2010].
Bat Conservation Trust (No date). UK Bat Species. See link.Date accessed: 4th May 2010].
The hazel dormouse (Muscardinus avellanarius) is legally protected, having undergone a decline to 50% of its original geographic range in the last century. The summer of 2010 will be the forth year of dormouse monitoring carried out in the woodlands around Hanningfield reservoir by staff at Essex & Suffolk Water and the Essex Wildlife Trust. The first survey was conducted in 2004 by Robin Cotrill from the Essex and Suffolk Dormouse Project and Essex & Suffolk Water staff. Plastic tubes were set up as potential nesting sites to allow dormouse presence to be determined. Several nests were found that year and, to the delight of all involved, a whole family of dormice was seen huddled in one of the nesting tubes.
After finding the rodent species at the reservoir, the Essex Biodiversity Project became involved in the monitoring efforts and set up a permanent transect of dormouse nesting boxes. Since then, staff from Essex & Suffolk Water and the Essex Wildlife Trust have surveyed the transect annually. Some years, the species has proved illusive and no animals have been seen. Yet nests are always found in the nest boxes, indicating that the dormouse continues to reside in the woodlands around the reservoir.
Records of amphibians are often obtained from routine site surveys and reports from local enthusiasts. Many of the lakes, ponds and former operational sludge lagoons on Essex & Suffolk water sites are ideal amphibian habitats. Vast numbers of toads migrate to the lakes at Lound in Suffolk each year to spawn and are helped to cross the road outside the site by a group of volunteers, an effort co-ordinated by Essex & Suffolk Water and The Broads Authority.
Great crested newt surveys are often necessary for our planned capital projects which are within close proximity to a pond. Several methods, often in conjunction, may be employed to conduct a great crested newt survey:
• Bottle-trapping: uses partially submerged plastic bottles to trap newts in the water.
• Egg search: live and dead vegetation is observed for egg presence.
• Torch survey: conducted at night, newts in the water are counted by torchlight.
• Netting: a pond net is used to catch newts.
• Pitfall trapping: pits are dug into the ground to trap migrating newts.
Natural England (2001). Great Crested Newt Mitigation Guidelines. Natural England, Peterborough, pp.75.
Wetland Bird Survey (WeBS)
The UK’s freshwaters are an important habitat for the many waterbirds which migrate from northern Europe and the Arctic in winter each year. The shrinking fragments of wetland within the UK are paramount for the survival of these bird species and measures are being taken to conserve this fragile habitat.
Monthly counts of the waterbirds are conducted as part of the Wetland Bird Survey (WeBS); a nationwide effort to monitor the migrating, non-breeding populations, estimate distribution and identify key sites used by these birds.
The survey, launched in 1993, is a partnership between the British Trust for Ornithology (BTO), the Royal Society for the Protection of Birds (RSPB) and the Joint Nature Conservation Committee (JNCC), with the data being used to aid the conservation of the waterbird populations and the wetland habitats upon which they depend.
The reservoirs owned by Essex & Suffolk Water provide a fantastic man-made wetland habitat for waterbirds and have been designated Sites of Special Scientific Interest for this very reason. Volunteers have carried out WeBS counts on both sites since for over 50 years.
RSPB (2010). New report reveals the ups and downs of Britain’s waterbirds. See link. Date accessed: 13th April 2010]
The Wetland Bird Survey (No date). WeBS – the wetland bird survey. See link.Date accessed: 13th April 2010].
The Wetland Bird Survey (No date). The history and the future of the wetland bird survey (WeBS). See link. Date accessed: 13th April 2010].
Breeding Bird Surveys, Ringing and Constant Effort Sites (CES). BTO website – no of ringers nationally.
Butterflies, moths and dragonflies
ocated on the site of Hanningfield Water Treatment Works in Essex, North Dam Meadows attracts an array of butterfly, moth, dragonfly and damselfly species. Local experts have been carrying out surveys each year since 2003, between April and September.
Since recording began, six species of damselfly, nine species of dragonfly, 23 species of moth and 24 species of butterfly have been seen on North Dam Meadows. Most of the moths observed are common throughout the UK, with the exception of the small magpie, the drinker, the small blood vein, the blood vein and the burnet companion, whose distributions are restricted to the south of Britain.
The dusky sallow has also been identified on the transect walks; a species which is found only in the south east of England and East Anglia. Amongst the migrant species are the silver y and the hummingbird hawk-moth, with the latter migrating from Africa in the summer months.
Butterfly Conservation (No date). Hummingbird hawk-moth. See link to Butterfly Conservation. Date accessed: 14th April 2010].
Ecological surveys are carried out every ten years on all key sites owned by us to determine the broad habitats present. Repeat surveys create a long-term botanical record for a site and allow the success of habitat management strategies to be evaluated. Where a habitat of particular conservation interest is noted, a second more specialist survey of that habitat is performed.
Habitats in severe decline or degradation are recognised nationally, having Biodiversity Action Plans which set UK conservation targets.
Our botanical surveys enable Biodiversity Action Plan habitats on our sites to be identified and action taken to ensure the existence of these areas for the future. Both the broad habitats and the Biodiversity Action Plan habitats are mapped on our GIS programme.
At Layer Pits in Layer de la Haye, several species of lichen were noted in a survey carried out in 2001 and remain at the site today. These species are indicative of a lowland heathland habitat. Of the expanse of lowland heathland that existed in the UK in the 1800s, only one sixth remains today. This habitat has therefore been identified as a priority habitat and is covered by a Habitat Action Plan. Other Biodiversity Action Plan habitats, such as acid grassland with green-winged orchids and ancient woodland, can also be found on our sites.
UK Biodiversity Action Plan (2007). Habitat action plan lowland heathland. Available from: http://www.ukbap.org.uk/ukplans.aspx?ID=15#1 [Date accessed: 14th April 2010].
Six reptile species are found in Britain, the most famous of the snakes being the adder (Vipera berus) which is renowned for its poisonous bite. The grass snake (Natrix natrix) and the smooth snake (Coronella austriaca), also found in Britain, are harmless. Britain is also home to two species of lizard, the sand lizard (Lacerta agilis) and the viviparous lizard (Lacerta vivipara). Often mistaken for a snake, the slow worm (Anguis fragilis) is in fact a legless lizard and is a commonly seen reptile.
Reptile surveys are incorporated into the protected species surveys carried out on our sites. Being cold-blooded or ecothermic, reptiles must bask in the morning sun to raise their body temperature, frequenting rocks and other natural or man-made surfaces. Reptile population size on our sites is estimated through the creation of artificial basking sites. 50cm2 basking mats are made from roofing felt and readily attract reptiles.