50 Fantastic Devon species!

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1 50 Fantastic Devon species! (weeks 11 15) Week 15 Great Crested Newt Triturus cristatus Photo: A Cornish Great crested newts cover a range over much of northern Europe, however through most of this range they are rare. The UK once had one of the strongest newt populations in Europe. Devon is on the western extent of the UK s newt population with a handful of sites where they are known to successfully breed. This low population and limited distribution is being better understood in the county through survey work by the Devon Reptile and Amphibian Group amongst others. A number of new sites have already been found or old sites reconfirmed. Of the three newt species in the UK, the great crested newt is the largest. They are dark in colour with an orange coloured stomach which had a pattern of dark markings which are unique to the individual, and the females tend to be larger than the males.

Photo: J Bastone Part of the scientific name for this species (Tritrus cristatus) cristatus comes from the Latin for crested, which the males have in the breading season.

2 Photo: J Bastone Part of the scientific name for this species (Tritrus cristatus) cristatus comes from the Latin for crested, which the males have in the breading season. They are one of a few species afforded the highest level of legislative protection, this includes disturbing them, so if found you should always contact an expert. Great crested newts live in a wide range of habitats as long as they have refuge and suitable ponds which have lots of weeds growing in them and no fish as they will eat newt eggs and larva. There are often small populations at different ponds within a proximity to each other, and individual adults will migrate between. Each spring they migrate from the sites they have hibernated in to the ponds where they will breed the same as frogs, but it occurs much more gradually than with frogs and toads. 50% of newt eggs will never hatch due to a chromosome defect. Both fully grown and immature newts are predators, mainly preying on small invertebrates, although occasionally an adult newt will attack larger pray like other smaller species of newt and large dragonflies. Sources: English Nature Great Crested newt conservation handbook, froglife. See also Devon Reptile and Amphibian Group

3 Week 14 Bog Hoverfly Eristalis cryptarum The bog hoverfly is another species holding on in Devon despite it s habitat being eroded. It used to be found over the whole of the southwest as far east as the New Forest. For a while it was believed to be extinct in the UK until it was rediscovered in 1993 on Dartmoor, to this day there are still only a few sites on the moor that it occurs. Like many other hoverflies it has evolved to mimic bees to avoid predation. As its name suggest the hoverfly tends to live in boggy areas, or more specifically valley mires, heathland and moorland. Usually in these areas it is associated with small water channels where there is an abundance of flowering plants for the adults to feed on. Very little is really known about this species as not much research has ever been carried out. It appears to prefer to fly on warm sunny days (although not too hot), and they usually fly low - very rarely flying more than one meter above the ground. There is also some evidence that there are three broods of the hoverfly each year as there seems to be three peeks in numbers every year. Photo: John Walters Males have even been known to chase off bumblebees, which are much bigger and more dangerous, whilst defending their territory. It is not sure what has caused such a dramatic decline in this species but it is believed that it could be related to the decline of traditional management systems such as decreased grazing causing habitats to become overgrown with shrubs, meaning there is more shade in the habitat than is optimal for the hoverflies survival. The bog hoverfly is a UK Biodiversity Action Plan (UK BAP) priority species

Source of information ARKive http://www.arkive.org/bog-hoverfly/eristalis-cryptarum/#text=all Week 13 Warren Crocus Romulea columnae The Warren or Sand Crocus is another case of small but beautiful.

4 Source of information ARKive Week 13 Warren Crocus Romulea columnae The Warren or Sand Crocus is another case of small but beautiful. It was discovered in 1834 at Dawlish Warren ( and until very recently, this plant was found no where else in Britain. It has now been recorded at a small site in Southern Cornwall but the association with Dawlish Warren will always be enshrined in it s name. With its lilac-blue flowers it grows on dry stable dunes amongst short grass. It grows very close to the ground and its tiny flowers appear briefly at the end of March/early April. In total nearly 600 different types of flowering plants have so far been recorded at Dawlish Warren. The high number of different species in such a relatively small area is due in part to the richness of habitat types found within the Reserve. Mobile dune, semi-fixed dune, fixed dune, salt marsh, scrub and freshwater wetland all have special plants which are adapted to the different prevailing conditions. Many of the Warren's special 'fixed dune' plants are very small - a way of coping with joint pressures of poor soil, dry summers, rabbit grazing and heavy trampling by human feet. Although most famous for the Warren Crocus (Romulea columnae), another of Britain's rarest and smallest plants grows at Dawlish Warren too - petalwort looks like a tiny lettuce only 2mm across! 'The Flora of Dawlish Warren' publication is available to purchase from the on site Visitor Centre if you would like to find out more.

science in 2010*. It has since been found in 4 other 1 kilometre squares, all in the Hembury Woods/Buckfastleigh/Dart Valley district.

5 Photo: Vicky Gardner Week 12 Ectoedemia heckfordi Currently only found in 4 places in Devon and no where else in the UK or World! Ectoedemia heckfordi (Nepticulidae) is a species of Microlepidoptera that was first found at Hembury Woods in 2004 by local lepidopterist Bob Heckford and described new to science in 2010*. It has since been found in 4 other 1 kilometre squares, all in the Hembury Woods/Buckfastleigh/Dart Valley district. Photo: Dr Erik J Van Nieukerken Currently E. heckfordi is known from nowhere else in the British Isles or indeed the world. This is despite the fact that the emerald green larva makes distinctive mines in leaves of Sessile Oak Quercus petraea and Pedunculate

Oak Quercus robur, a photograph of the mine has been on the British Leafminers website www.leafmines.co.

6 Oak Quercus robur, a photograph of the mine has been on the British Leafminers website since late 2004 and it has been searched for in other areas of Devon as well as elsewhere in Britain by several Microlepidopterists. Photo: Ian Thirlwell The mines are large elongated blotches with frass concentrated in two lines along the edges. The larva occurs from late August to early September. Currently it is the only endemic species of Microlepidoptera known from the British Isles. Although the moth has a wingspan of less than 6 mm, there was a lot of media coverage after publication of its description. Also, every day during 2010 The Natural History Museum, London published on their website a fact file on various organisms, both plant and animal, to celebrate the UN's international Year of Biodiversity and on 2 September 2010 this was the Species of the Day on that website. Week 11 Hedgehog Harvestman (Centetostoma bacciliferum) Devon is the only county where this bizzare looking arachnid is found. It was only discovered in Britain in 1988 when it was found in Plymouth. It is about

7 1.5cm across including the legs and can be found under rocks in a few limestone quarries and adjacent scrub. Little is known about its life history though adults have been found in the spring and autumn. There are approximately 30 species of Harvestman in the UK and they vary considerably. Having eight legs, Harvestmen belong to the same order (Arachnida) as spiders, however they are actually very different. They have only two eyes which are located on the front part of the body, where as spiders have eight eyes. Their body consists of just one element where several sections are fused together, most insects have at least two parts which are jointed. Harvestmen can neither spin threads nor build webs, nor are capable of producing venom. Having said all of that it s an easy mistake to make at first glance. Photo: John Walters The best known harvestmen have very long legs and when threatened are able to loose one or more. The legs continue to twitch after they are detached. This is because there are 'pacemakers' located in the ends of the first long segment (femur) of their legs. These pacemakers send signals via the nerves to the muscles to extend the leg and then the leg relaxes between signals. While some harvestman's legs will twitch for a minute, other kinds have been recorded to twitch for up to an hour. The twitching has been hypothesized as a means to keep the attention of a predator while the harvestman escapes. They can still get along with only 3 legs if the need arises. Even though some harvestmen are carnivores, most will eat almost anything: from freshly caught prey to animals already dead and excretes or plants. Most harvestmen reach their adult stage in autumn and their small bodies on long feet are associated with the hay carts used by farmers in the old days. This

8 association is how they got their name although nowadays you re more likely to spot one in the garden shed. Photo: John Walters

Acorn Ecology Certificate Course Self-Study Tutorial. British Reptile & Amphibian ID ( and a bit about surveying too!)

Acorn Ecology Certificate Course Self-Study Tutorial British Reptile & Amphibian ID ( and a bit about surveying too!) Resources Herpetofauna Workers Manual Great Crested Newt Conservation Handbook FSC