Another event! Our first Bat Blitz event on Saturday August 15th 2015. Do join us if you can. 

Another great walk coming up on the 8th of August. 

Common Pipistrelle

Common pipistrelle on rock (© Rosie Corner / Bat Conservation Trust)

A widespread species of bat, the common pipistrelle (Pipistrellus pygmaeus) is distributed throughout UK. It is a generalist species and can be found in a wide variety of habitats, including urban and suburban environments such as parks, gardens and around street lamps.

The common pipistrelle is a small, brown bat with triangular ears. It has a dark face, (almost black) with black ears. It has a two toned fur; black rooted and brown outer. Like the Soprano Pipistrelle, the common pipistrelle weight is normally around 3 – 8g (the weight of a two pence coin). Maternity colonies are formed from May and young are born around June/July (1 pup to each female). The neonates (newborns) can weigh 3.3g in 10 days, 4.1 g in 20 days, are independent at 4 weeks and foraging by themselves in 6 weeks. By the end of their first autumn young female bats will have reached sexual maturity.

Calls of the common pipistrelle can be picked up on a heterodyne detector between 45kHz – 70kHz. The calls sounds like a series of clicks and wet slaps and at the peak frequency of 45kHz, the deepest, clearest calls can be heard. In general most calls made by bats are normally above our hearing range. However, young children and adults with exceptionally good hearing can hear the ‘chonk’ sounding social calls made by pipistrelles (around 22kHz), without the aid of a detector.

On a sonogram, the shape of a pipistrelle call is a distinctive ‘hook’ or ‘hockey stick’.A common pipistrelle recorded on an Echo Meter touch
outside All Saints Church, Besthorpe on the 4th July 2015 

Emergence time for a common pipistrelle is around 20 minutes after sunset. It flies and forages about 2 – 10m above ground, ducking and diving and catching its prey on the wing. It eats mainly flies (Diptera) and occasionally midges and mosquitos. Its distinctive jerky, fast and erratic flight is easily recognised.  In fact it is the bat you are most likely to see when out in your garden at dusk.

Common pipistrelles are a synanthropic species (closely associated with humans). Both their summer and winter roosts are located on the outside of buildings under wall claddings, cavity walls, eaves and roof coverings. Occasionally they will also roost in trees and bat boxes. Females are less loyal to their roost compared to other species of bats. They have been known to move their maternity colonies every 12 days. Though populations are stabilising, due to their dependence on our buildings, pipistrelles are still very vulnerable to changes such a building renovations and timber treatments.

Shape, colour and size will help you with moth identification. 

Another walk in Great Ellingham on the 25th of July. If you are interested, please book.

A nocturnal walk along the Wensum Way

Our next walk saw us visiting the lovely All Saints Church in Swanton Morley on Saturday 20^th of June 2015. Built in the 1300s, All Saints is a grade I listed building, located close to the Wensum Way. It has had a long history with bats, with a maternity colony of Natterer’s bats using the building, and has been involved with recent research looking into ways to implement techniques, that will provide a solution for churches affected by large bat colonies, without causing undue harm to the resident bats.

At 21.00, we welcomed 7 people plus 2 volunteers, Laura and Jamie. As the sun began to set, we headed down to the Wensum Way, a Norfolk County Council Trail, aptly called the ‘River Walk’ by the locals. Taking us into a beautiful Norfolk landscape consisting of open pastureland, hedgerows, and fragmented woodland, it looked like promising territory for our walk.

Around 10 minutes into the walk, we heard our first bat, a Noctule. Looking up we saw 2 Noctules flying above our heads (Noctule prefers to fly in straight lines high up above the tree line, over open habitat), followed shortly by a few others. Seeing these many Noctules, indicated to us that their roost was probably nearby. Noctules tend to roost in trees, particularly ones that have old woodpecker holes. We then heard our first pipistrelle, a Soprano Pipistrelle, one of our smallest bats weighing between 4- 7g.

Learning how to use a bat detector © Norfolk Wild Nights, Sonia Reveley

Progressing towards the River Wensum, we looked back towards the church and we were rewarded with a view of the sunset lighting up the sky with flashes of red, yellows, and gold. This view was in stark contrast with the sight we saw when we arrived at the side of the river, a darkening horizon and mist rolling into the fields. It was here that we heard and saw our first Daubenton’s bat, a Myotis species that prefers water habitats and is aptly nicknamed ‘the water bat’. Having satisfied ourselves with listening to Daubenton’s and Soprano Pipistrelles by the riverside, we started our journey back to the church and heard our first Natterer’s, most likely part of the colony exiting from the church. In addition, we also heard some Common Pipistrelles as they flew along the hedgerows.

On arriving back to the church faced with the possibility of getting caught up in the impending rainstorm, we quickly checked the moth trap that we set up earlier. We found a Straw Dot, Small Magpie, Heart and Dart and 2 Dark Arches. Afterwards when packing up the equipment we also found an Elephant Hawkmoth and a Figure of Eighty moth.

Moth trapping © Norfolk Wild Nights, Sonia Reveley

The Small Magpie is a micro moth, part of a group of smaller moths regularly caught in moth traps. This moth is common and widespread and has distinctive black/grey markings and yellow body parts. It flies around in June and July, so now is the best time to find them in your trap. It is found in gardens, woodland, fens, heathland, grassland, and scrub. The larva feeds on nettles and occasionally woundwort.

The Figure of Eighty is a quite a distinctive moth. It has a white ‘80’ mark on its forewing, which gives it its name. It flies around from May to July and is found in woodland, parks, heathland, grassland, and gardens. The larva feeds on aspen and poplars.

Thank you all for coming along. Your support for the project has been much appreciated.