Start Point to Bolt Tail invertebrates

1. About

The unique geology of the coastline at the southern tip of Devon is home to an exceptional range of rare and unique invertebrates, some of which are found nowhere else in Britain.

SpeciesA group of similar organisms that can breed and exchange gen... More which need particular action or attention are listed as Devon Special SpeciesLorem ipsum dolor sit amet consectetur adipiscing. and discussed below.

Other Devon Special Species which are found on this stretch of coast but have a wider distribution are discussed in the north and south Devon coastal invertebrate group. These include lizard weevils, the variable meadow fly and rare moths such as the Devonshire wainscott and beautiful gothic.

Much of this area falls within either Prawle Point and Start Point SSSISite of Special Scientific Interest More or Bolt Head to Bolt Tail SSSI. However, many of the species in this group are not listed on the SSSI citations and may also rely on habitatsThe natural environment in which an animal, plant or other o... More that lie outside the SSSI.

Key pressures and opportunities

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Habitat management

Lack of grazing is causing a loss of sunny, open and bare ground that’s critical for many species in this group. Species are threatened by shading from scrubLand with thick vegetation that includes wildflowers, grasse... More encroachment, particularly by blackthorn and bramble.

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Climate change

Erosion keeps coastal head deposits open. Rising sea levels may accelerate this, with more storms causing larger and more frequent landslips. These conditions could be hard for invertebrates such as spiders and bees to adapt to, as suitable areas become more isolated and populations more likely to fluctuate. 

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Invasive non-native species

In some parts of Britain, invasive members of the South African plant family Aizoaceae have colonised coastal cliffs. The main problem species is hottentot-fig (Carpobrotus edulis), which is well-established at Croyde Bay in north Devon. It’s also been recorded on the south Devon coast and could become a problem.The garden rose Rosa rugosa is spreading on the south Devon coast. This is not yet a significant problem but as for hottentot-fig could rapidly spread and become a significant problem for native wildlife.

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Life on the Edge

Life on the edge is funded by the National Lottery Heritage Fund. The project focuses on the rare invertebrates and plants found along this stretch of coast and provides significant opportunities for nature recovery over the next few years. See Inspiration below.

2. What we need to do and where

Devon Special Species

A six banded nomad sits on a grey rock facing the bottom right corner of the photo. It has orangey-yellow legs, oragey brown antennae, a black and yellow striped abdomen and a fuxxy black body and head. The dark, clear wings lay on top of one another against the abdomen, the large dark eyes are just below the antennae on on the head, and a lighter, yellowey mouthpart is just visible below those.

Six-banded nomad bee and long-horned bee

Nomada sexfasciata and Eucera longicornis

The six-banded nomad bee was once widely distributed across southern Britain but is now Britain’s rarest bee, restricted to a single site along the coast at Prawle Point.

Nomad bees are known as ‘cuckoo bees’ as they lay their eggs in the nests of other bee species. The six-banded nomad bee is dependent on the long-horned bee, which nests in bare soil on the warm, soft, south-facing cliffs and feeds on plants in the pea family such as everlasting pea, kidney vetch and other vetches and clovers. Long-horned bees are still present in this area but are thought to be declining due to loss of suitable habitatThe natural environment in which an animal, plant or other o... More. They’re listed as a Focus Species as they’re critical for the six-banded nomad bee.

Devon red-legged robberfly

Neomochtherus pallipes

The first British record of this robberfly was in 1990 at Woodcombe, near Prawle Point when several were seen on a footpath. It hasn’t been seen since but there’s a strong possibility that it survives somewhere along the coastal strip between Prawle Point and Start Point. It is hard to find due to the inaccessibility of much of the coastal slope and due to its short flight period. In 2012 a single male was recorded in Berkshire. In 2016 it was found on a hillside in Shropshire but hasn’t been seen again since 2020. It hasn’t been found anywhere else in England and is considered critically endangered.

The robberfly lives on a mosaic landscape of small fields, soft cliffs, rank grassland, scrub and rocky knolls. It needs sandy soils and warm, open, south-facing slopes where it can bask on rocks in the sun. Its habitat is threatened by bramble and blackthorn, which due to a lack of grazing have increased considerably at Woodcombe and at many other similar coastal sites. Management for the Devon red-legged robberfly is also likely to benefit the hornet robberfly (Asilus crabroniformis) a national conservation priority.

[RW1]S41 species

Against a grey fuzzy background, the moon spider is in the centre of the photo facing to the right. It has eight shiny, red-brown legs, a furry black abdomen with two broken stripes towards the rear, and the body is a shiny, hairy very dark brown-black. The head is not clearly visible but appears to match the main body.

Moon spider and other cliff spiders

Nine species of rare spider live on the warm, sunny, sparsely-vegetated sediments between Bolt Head and Froward Point. Like all spiders, they’re predatory, feeding entirely on other invertebrates, including ants. All the sites for this assemblageA group of different species that are found together in one ... More fall within either Prawle Point and Start Point SSSI or Bolt Head to Bolt Tail SSSI. No other county has records of all nine species in this assemblage. 

The rarest species is the moon spider (Callilepis nocturna), which is the Focus Species for this group. The jumping spider (Euophrys herbigrada) occurs more widely on the south coast between Cornwall and East Sussex. The ground spider (Micaria albovittata) has a similar range, and also occurs on some heaths a short distance inland. Other threatened spiders which occur here are also found in stony and sparsely-vegetated maritime grasslands. These are Acartauchenius scurrilis, Agroeca cuprea, Cozyptila blackwalli, Gnaphosa lugubris, Lasaeola prona, Phlegra fasciata and Zelotes longipes. 

Moon spider

Callilepsis nocturna

This is the rarest spider in this group and in Britain is only found around Prawle Point and at single sites in Pembrokeshire and the Isle of Wight. Unlike other ground spiders, which are nocturnal, on sunny days the moon spider can be seen running over bare ground.

Rather than spinning webs to catch its prey, the moon spider builds retreats, which (like those of E. herbigrada and M. albovittata) it lines with silk. It builds them on bare ground, under rocks and in burrows that have been abandoned by solitary bees. It’s been seen capturing ants and carrying them back to its retreat.

The large, rotund, black oil beetle, appears to be sitting almost upright against a backdrop of short green grass. The beetle's large, long, round abdomen has faint segments along the whole length and comparatively tiny wing cases at the top where it joins the body. The body is roughly a tenth the size of the abdomen with the head being roughly the same size, apart from the large mouthparts. Both the legs and antennae have multiple obvious segments. Every part of the beetle is black.

Oil beetles

Oil beetles are named for the bitter, oil-like fluid they produce from their knee joints to deter predators. All British oil beetles are parasites of solitary mining bees. Female oil beetles lay eggs in batches of up to 1,000, in burrows they dig into sparsely-vegetated soil. The eggs hatch into larvae known as triungulins, which climb into flowerheads and hitch a ride on the backs of solitary bees. Once in the bee’s nest, the larvae feed on the bee’s eggs and stores of pollen and nectar.

Oil beetles are largely found on flower-rich coastal grasslands where their host mining bees are found.

Mediterranean oil beetle

Meloe mediterraneus

This rare species is only found in Devon and Sussex. The main Devon population is in the Prawle Point and Start Point SSSI, but has also recently been found on the East Devon Pebblebed Heaths SSSI and Bolt Head to Bolt Tail SSSI. They’re active on mild nights between September and April and have been seen feeding on leaves of soft grasses and buttercups.

Short-necked oil beetle

Meloe brevicollis

In Devon, the short-necked oil beetle is mainly found in the Bolt Head to Bolt Tail SSSI. It’s also found in the outer Hebrides, Wiltshire and Pembrokeshire. Adults can be seen in the day from March to June, often feeding on the leaves of hawkbits and other yellow dandelion-like species.

Actions

Manage and restore (through light grazing and scrub control) a mosaic of connected habitats with flower-rich grasslands, bare ground, scattered scrub and trees, wet seepages, eroding cliffs, shingle and critical foodplants.

Prevent scrub encroaching on open habitats which support rare species such as the spiders.   
Monitor and control invasive species such as hottentot-fig and rugosa rose.
Minimise the use of, and target applications of, pesticides and avermectins to reduce impacts on invertebrates.
Monitor and research the Devon Species of Conservation concern along this coast to inform conservation action.

Other relevant actions

See the wildlife-rich grassland page for more details and actions on grasslands and the coast page for other relevant actions and coastal species.

Where to focus action

High Opportunity Areas: Start Point to Bolt Tail Coastal Wildbelt. See Mapping.

3. Inspiration

Case studies

Life on the Edge

Life On the Edge is funded by the National Lottery Heritage Fund. The project works with the National Trust, farmers, communities and wildlife experts to reverse the decline of rare species, including those listed above. It focuses on five hotspots: Wembury, the Erme, Bolt Head to Bolt Tail, Prawle Point to Start Point, and Brownstone to Berry Head.

Life on the Edge an introduction

Where to visit

Always follow the Countryside Code and keep to footpaths and sites that are managed for public access. 

A few good places to see Start Point to Bolt Tail invertebrates are listed below. For more details on these and other places to visit see the Explore Devon website.   

Bolberry Down

Bolberry Down is managed by the National Trust. It has a cliff top car park and a section of the coast path that’s accessible by wheelchair. It’s the easiest to access section of Bolt Tail to Start Point and has stunning views and a café.

Prawle Point

With crumbling cliffs and wildflower-rich cliff tops, the gorgeous landscape at Prawle Point is a great place for bug watching.

4. Find out more

The south Devon coast is identified as an Important Invertebrate Area by Buglife.

Buglife has information about the Devon red-legged robberfly on its website.

South Devon National Landscape | South Devon National Landscape

Information on the Heritage Lottery funded project focused on this stretch of coast Life on the Edge – Buglife projects

The Open University Geological Society has information about the unique geology along this stretch of coast The Start Complex around Prawle Point in South Devon

The Spider and Harvestman Recording Scheme website has information on all spiders.

The Bees, Wasps & Ants Recording Society website has information on all bees, ants and wasps.

The British Arachnological Society website has facts on all spiders and other arachnids.

Start Point to Bolt Tail invertebrates group

1. About