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87-639: Stour Estuary is a 2,523 hectare biological and geological Site of Special Scientific Interest which stretches from Manningtree to Harwich in Essex and Suffolk . It is also an internationally important wetland Ramsar site , a Special Protection Area and a Nature Conservation Review site. It is part of the Suffolk Coast and Heaths Area of Outstanding Natural Beauty , and there are Geological Conservation Review sites in Wrabness , Stutton , and Harwich Part of

174-457: A Hemianax ephippiger native to North Africa, and an unidentified darter species. In Kamchatka , only a few species of dragonfly including the treeline emerald Somatochlora arctica and some aeshnids such as Aeshna subarctica are found, possibly because of the low temperature of the lakes there. The treeline emerald also lives in northern Alaska , within the Arctic Circle , making it

261-631: A reed or other emergent plant, and moults ( ecdysis ). Anchoring itself firmly in a vertical position with its claws, its exoskeleton begins to split at a weak spot behind the head. The adult dragonfly crawls out of its nymph exoskeleton , the exuvia , arching backwards when all but the tip of its abdomen is free, to allow its exoskeleton to harden. Curling back upwards, it completes its emergence, swallowing air, which plumps out its body, and pumping haemolymph into its wings, which causes them to expand to their full extent. Dragonflies in temperate areas can be categorized into two groups: an early group and

348-409: A branchial chamber, located around the fourth and fifth abdominal segments. These internal gills consist originally of six longitudinal folds, each side supported by cross-folds. But this system has been modified in several families. Water is pumped in and out of the abdomen through an opening at the tip. The naiads of some clubtails ( Gomphidae ) that burrow into the sediment, have a snorkel-like tube at

435-580: A continuation of the historical management of the land. Where an owner or occupier is unwilling or unable to carry out management, ultimately the conservation body can require it to be done. Public bodies which own or occupy an SSSI have a duty to manage it properly. Site management statements for SSSI in Scotland are available to download from the NatureScot website using the "Sitelink" facility. The law protecting SSSIs now covers everyone, not just public bodies and

522-627: A group that included one of the largest insects that ever lived, Meganeuropsis permiana from the Early Permian , with a wingspan around 750 mm (30 in). The Protanisoptera , another ancestral group that lacks certain wing-vein characters found in modern Odonata, lived in the Permian . Anisoptera first appeared during the Toarcian age of the Early Jurassic , and the crown group developed in

609-501: A huge, extensible labium , armed with hooks and spines, which is used for catching prey. This labium is folded under the body at rest and struck out at great speed by hydraulic pressure created by the abdominal muscles. Both damselfly and dragonfly nymphs ventilate the rectum, but just some damselfly nymphs have a rectal epithelium that is rich in trachea , relying mostly on three feathery external gills as their major source of respiration. Only dragonfly nymphs have internal gills, called

696-567: A hydraulic function to expand the body between nymphal stages ( instars ) and to expand and stiffen the wings after the adult emerges from the final nymphal stage. The leading edge of each wing has a node where other veins join the marginal vein, and the wing is able to flex at this point. In most large species of dragonflies, the wings of females are shorter and broader than those of males. The legs are rarely used for walking, but are used to catch and hold prey, for perching, and for climbing on plants. Each has two short basal joints, two long joints, and

783-408: A later one. In any one area, individuals of a particular "spring species" emerge within a few days of each other. The springtime darner ( Basiaeschna janata ), for example, is suddenly very common in the spring, but disappears a few weeks later and is not seen again until the following year. By contrast, a "summer species" emerges over a period of weeks or months, later in the year. They may be seen on

870-474: A long way upstream of a wetland SSSI might require consultation. Some developments might be neutral or beneficial, even if they are within the SSSI itself – the critical point is whether they harm the interest features. The owners and occupiers of SSSIs are required (Scotland, England, Wales) to obtain consent from the relevant nature conservation body if they want to carry out, cause or permit to be carried out within

957-522: A noniridescent blue that is produced structurally by scatter from arrays of tiny spheres in the endoplasmic reticulum of epidermal cells underneath the cuticle. The wings of dragonflies are generally clear, apart from the dark veins and pterostigmata. In the chasers (Libellulidae), however, many genera have areas of colour on the wings: for example, groundlings ( Brachythemis ) have brown bands on all four wings, while some scarlets ( Crocothemis ) and dropwings ( Trithemis ) have bright orange patches at

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1044-428: A packet of sperm from his primary genital opening on segment 9, near the end of his abdomen, to his secondary genitalia on segments 2–3, near the base of his abdomen. The male then grasps the female by the head with the claspers at the end of his abdomen; the structure of the claspers varies between species, and may help to prevent interspecific mating. The pair flies in tandem with the male in front, typically perching on

1131-407: A proposed activity would not affect the interest or is beneficial to it, then the conservation body will issue a "consent" allowing it to be carried out without further consultation. If it would be harmful, the conservation body may issue consent subject to conditions or refuse the application. If consent in writing is not given the operation must not proceed. Conditions may cover any relevant aspect of

1218-494: A rigid, box-like structure with internal bracing, and provide a robust attachment for the powerful wing muscles inside. The thorax bears two pairs of wings and three pairs of legs. The wings are long, veined, and membranous, narrower at the tip and wider at the base. The hindwings are broader than the forewings and the venation is different at the base. The veins carry haemolymph , which is analogous to blood in vertebrates, and carries out many similar functions, but which also serves

1305-416: A series of nymphal stages from which the adult emerges. Eggs laid inside plant tissues are usually shaped like grains of rice, while other eggs are the size of a pinhead, ellipsoidal, or nearly spherical. A clutch may have as many as 1500 eggs, and they take about a week to hatch into aquatic nymphs or naiads which moult between six and 15 times (depending on species) as they grow. Most of a dragonfly's life

1392-428: A site may contain strata containing vertebrate fossils, insect fossils and plant fossils and it may also be of importance for stratigraphy . Geological sites fall into two types, having different conservation priorities: exposure sites, and deposit sites. Exposure sites are where quarries , disused railway cuttings, cliffs or outcrops give access to extensive geological features, such as particular rock layers. If

1479-425: A standard list for that country. The ORCs/OLDs are not "banned" activities – the list includes activities which would damage the interest, but also many which might be beneficial. For example, " grazing " (a standard item on the list) would require consent, even on a chalk grassland or heathland where grazing is an essential part of management. In England and Wales the list of OLDs is almost the same for each SSSI – and

1566-475: A suitable substrate, but also the male hovering above her or continuing to clasp her and flying in tandem. This behaviour following the transfer of sperm is termed as mate guarding and the guarding male attempts to increase the probability of his sperm fertilising eggs. Sexual selection with sperm competition occurs within the spermatheca of the female and sperm can remain viable for at least 12 days in some species. Females can fertilise their eggs using sperm from

1653-427: A sunlit stretch of shallow water, a special plant species, or the preferred substrate for egg-laying. The territory may be small or large, depending on its quality, the time of day, and the number of competitors, and may be held for a few minutes or several hours. Dragonflies including Tramea lacerata (black saddlebags) may notice landmarks that assist in defining the boundaries of the territory. Landmarks may reduce

1740-583: A territory against others of their own species, some against other species of dragonfly and a few against insects in unrelated groups. A particular perch may give a dragonfly a good view over an insect-rich feeding ground; males of many species such as the Pachydiplax longipennis (blue dasher) jostle other dragonflies to maintain the right to alight there. Defending a breeding territory is common among male dragonflies, especially in species that congregate around ponds. The territory contains desirable features such as

1827-438: A three-jointed foot, armed with a pair of claws. The long leg joints bear rows of spines, and in males, one row of spines on each front leg is modified to form an "eyebrush", for cleaning the surface of the compound eye. The abdomen is long and slender and consists of 10 segments. Three terminal appendages are on segment 10; a pair of superiors (claspers) and an inferior. The second and third segments are enlarged, and in males,

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1914-538: A true clade ]   Libellulidae (skimmers) About 3,012 species of dragonflies were known in 2010; these are classified into 348 genera in 11 families . The distribution of diversity within the biogeographical regions are summarized below (the world numbers are not ordinary totals, as overlaps in species occur). Dragonflies live on every continent except Antarctica. In contrast to the damselflies (Zygoptera), which tend to have restricted distributions, some genera and species are spread across continents. For example,

2001-460: A twig or plant stem. The female then curls her abdomen downwards and forwards under her body to pick up the sperm from the male's secondary genitalia, while the male uses his "tail" claspers to grip the female behind the head: this distinctive posture is called the "heart" or "wheel"; the pair may also be described as being "in cop". Egg-laying (ovipositing) involves not only the female darting over floating or waterside vegetation to deposit eggs on

2088-452: Is also conflict between the males and females. Females may sometimes be harassed by males to the extent that it affects their normal activities including foraging and in some dimorphic species females have evolved multiple forms with some forms appearing deceptively like males. In some species females have evolved behavioural responses such as feigning death to escape the attention of males. Similarly, selection of habitat by adult dragonflies

2175-471: Is cosmopolitan, occurring on all continents in the warmer regions. Most Anisoptera species are tropical, with far fewer species in temperate regions. Some dragonflies, including libellulids and aeshnids, live in desert pools, for example in the Mojave Desert , where they are active in shade temperatures between 18 and 45 °C (64 and 113 °F); these insects were able to survive body temperatures above

2262-516: Is governed by published SSSI Selection Guidelines. Within each area, a representative series of the best examples of each significant natural habitat may be notified, and for rarer habitats all examples may be included. Sites of particular significance for various taxonomic groups may be selected (for example birds, dragonflies , butterflies , reptiles, amphibians , etc.)—each of these groups has its own set of selection guidelines. Conservation of biological SSSI/ASSIs usually involves continuation of

2349-420: Is not necessarily absolute—generally it requires the SSSI interest to be considered properly against other factors. Local planning authorities are required to have policies in their development plans which protect SSSIs. They are then required to consult the appropriate conservation body over planning applications which might affect the interest of an SSSI (such a development might not be within or even close to

2436-416: Is not random, and terrestrial habitat patches may be held for up to 3 months. A species tightly linked to its birth site utilises a foraging area that is several orders of magnitude larger than the birth site. Mating in dragonflies is a complex, precisely choreographed process. First, the male has to attract a female to his territory, continually driving off rival males. When he is ready to mate, he transfers

2523-441: Is often pronounced "triple-S I". Sites notified for their biological interest are known as Biological SSSIs (or ASSIs), and those notified for geological or physiographic interest are Geological SSSIs (or ASSIs). Sites may be divided into management units, with some areas including units that are noted for both biological and geological interest. Biological SSSI/ASSIs may be selected for various reasons, which for Great Britain

2610-456: Is spent as a nymph, beneath the water's surface. The nymph extends its hinged labium (a toothed mouthpart similar to a lower mandible, which is sometimes termed as a "mask" as it is normally folded and held before the face) that can extend forward and retract rapidly to capture prey such as mosquito larvae, tadpoles , and small fish. They breathe through gills in their rectum , and can rapidly propel themselves by suddenly expelling water through

2697-554: The Early Jurassic . Dragonflies are represented in human culture on artefacts such as pottery, rock paintings, statues, and Art Nouveau jewellery. They are used in traditional medicine in Japan and China, and caught for food in Indonesia. They are symbols of courage, strength, and happiness in Japan, but seen as sinister in European folklore. Their bright colours and agile flight are admired in

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2784-739: The Eocene Harwich Formation and the succeeding London Clay . Wrabness has the most complete succession of ashes showing the importance of volcanism in southern England in the early Eocene. Stutton has fossils dating to the mid- Pleistocene , including extinct mammals such as straight-tusked elephants , mammoths and giant deer . 51°57′14″N 1°10′26″E  /  51.954°N 1.174°E  / 51.954; 1.174 Site of Special Scientific Interest A site of special scientific interest ( SSSI ) in Great Britain , or an area of special scientific interest ( ASSI ) in

2871-640: The Isle of Man and Northern Ireland , is a conservation designation denoting a protected area in the United Kingdom and Isle of Man . SSSI/ASSIs are the basic building block of site-based nature conservation legislation and most other legal nature/geological conservation designations in the United Kingdom are based upon them, including national nature reserves , Ramsar sites , Special Protection Areas , and Special Areas of Conservation . The acronym "SSSI"

2958-449: The Marine and Coastal Access Act 2010 ). Access to SSSIs is the same as for the rest of the countryside of the relevant country. Most SSSIs/ASSIs are in private ownership and form parts of working farms, forests and estates. In Scotland, people may use their rights of responsible access to visit SSSIs. When designating an SSSI/ASSI, the relevant nature conservation body must formally notify

3045-517: The Middle Jurassic . They retain some traits of their distant predecessors, and are in a group known as the Palaeoptera , meaning 'ancient-winged'. Like the gigantic griffinflies, dragonflies lack the ability to fold their wings up against their bodies in the way modern insects do, although some evolved their own different way to do so. The forerunners of modern Odonata are included in a clade called

3132-927: The National Parks and Access to the Countryside Act 1949 , but the current legal framework for SSSIs is provided in England and Wales by the Wildlife and Countryside Act 1981 , amended in 1985 and further substantially amended in 2000 (by the Countryside and Rights of Way Act 2000 ), in Scotland by the Nature Conservation (Scotland) Act 2004 and in Northern Ireland by the Nature Conservation and Amenity Lands (Northern Ireland) Order 1985 . SSSIs are also covered under

3219-561: The Water Resources Act 1991 and related legislation. An SSSI may be made on any area of land which is considered to be of special interest by virtue of its fauna , flora , geological or physiographical / geomorphological features. SSSI notification can cover any "land" within the area of the relevant nature conservation body, including dry land, land covered by fresh water . The extent to which an SSSI/ASSI may extend seawards differs between countries. In Scotland an SSSI may include

3306-544: The Gomphidae (clubtails) live in running water, and the Libellulidae (skimmers) live in still water. Some species live in temporary water pools and are capable of tolerating changes in water level, desiccation, and the resulting variations in temperature, but some genera such as Sympetrum (darters) have eggs and nymphs that can resist drought and are stimulated to grow rapidly in warm, shallow pools, also often benefiting from

3393-560: The ORC lists for each SSSI and removed those activities that were unlikely to happen and if they were to would be unlikely to damage the protected natural features, and other activities adequately regulated by other statutory regimes. The intention of this was to remove the need for owners and occupiers to obtain SSSI consent as well as licences/ permits from other authorities (who must consult NatureScot prior to determining such applications). Purely geological SSSIs often have much shorter OLD lists. If

3480-1023: The Panodonata, which include the basal Zygoptera (damselflies) and the Anisoptera (true dragonflies). Today, some 3,000 species are extant around the world. The relationships of anisopteran families are not fully resolved as of 2021, but all the families are monophyletic except the Corduliidae , and the Austropetaliidae are sister to the Aeshnoidea :   Austropetaliidae   Aeshnoidea (hawkers)   Petaluridae (petaltails)   Gomphidae (clubtails)   Neopetaliidae   Cordulegastridae (goldenrings)   Chlorogomphidae   Synthemistidae (tigertails)   many Synthemistidae genera, incertae sedis   Macromiidae (cruisers)  " Corduliidae " (emeralds) [ not

3567-581: The SSSI Register, hosted by The Registers of Scotland . Further information about SSSIs in Scotland is available on the NatureScot website. The decision to notify an SSSI is made by the relevant nature conservation body (the appropriate conservation body ) for that part of the United Kingdom: Northern Ireland Environment Agency , Natural England , NatureScot or Natural Resources Wales . SSSIs were originally set up by

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3654-414: The SSSI any of the activities listed in the notification. Formerly these activities were called 'potentially damaging operations' or PDOs. Under the current legal arrangements they are called 'operations requiring consent' or ORCs (Scotland), or 'operations likely to damage the SSSI interest' or OLDs (England & Wales). The list of ORCs/OLDs for each SSSI is unique to that site – though all are derived from

3741-402: The SSSI itself). The effect of this is to prevent development which harms the interest – except where the value of that interest is over-ridden by some more important factor, for example a requirement for a major road or port or oil pipe. The requirement for consultation covers any development which might affect the interest, not just developments within the SSSI itself – for example, a development

3828-497: The absence of predators there. Vegetation and its characteristics including submerged, floating, emergent, or waterside are also important. Adults may require emergent or waterside plants to use as perches; others may need specific submerged or floating plants on which to lay eggs. Requirements may be highly specific, as in Aeshna viridis (green hawker), which lives in swamps with the water-soldier, Stratiotes aloides . The chemistry of

3915-478: The anus. Some naiads, such as the later stages of Antipodophlebia asthenes , hunt on land. The nymph stage of dragonflies lasts up to five years in large species, and between two months and three years in smaller species. When the naiad is ready to metamorphose into an adult, it stops feeding and makes its way to the surface, generally at night. It remains stationary with its head out of the water, while its respiration system adapts to breathing air, then climbs up

4002-453: The back of the head that grip structures on the front of the first thoracic segment. This arrester system is unique to the Odonata, and is activated when feeding and during tandem flight. The thorax consists of three segments as in all insects. The prothorax is small and flattened dorsally into a shield-like disc, which has two transverse ridges. The mesothorax and metathorax are fused into

4089-623: The blue-eyed darner Rhionaeschna multicolor lives all across North America, and in Central America; emperors Anax live throughout the Americas from as far north as Newfoundland to as far south as Bahia Blanca in Argentina, across Europe to central Asia, North Africa, and the Middle East. The globe skimmer Pantala flavescens is probably the most widespread dragonfly species in the world; it

4176-602: The closely related damselflies , which make up the other odonatan infraorder ( Zygoptera ) and are similar in body plan , though usually lighter in build; however, the wings of most dragonflies are held flat and away from the body, while damselflies hold their wings folded at rest, along or above the abdomen. Dragonflies are agile fliers, while damselflies have a weaker, fluttery flight. Dragonflies make use of motion camouflage when attacking prey or rivals. Dragonflies are predatory insects , both in their aquatic nymphal stage (also known as "naiads") and as adults. In some species,

4263-429: The costs of territory establishment, or might serve as a spatial reference. Some dragonflies signal ownership with striking colours on the face, abdomen, legs, or wings. The Plathemis lydia (common whitetail) dashes towards an intruder holding its white abdomen aloft like a flag. Other dragonflies engage in aerial dogfights or high-speed chases. A female must mate with the territory holder before laying her eggs. There

4350-426: The cuticle that reflect blue light. Greens often combine a structural blue with a yellow pigment. Freshly emerged adults, known as tenerals, are often pale, and obtain their typical colours after a few days. Some have their bodies covered with a pale blue, waxy powderiness called pruinosity; it wears off when scraped during mating, leaving darker areas. Some dragonflies, such as the green darner, Anax junius , have

4437-837: The designating authority is NatureScot ; the role in Wales is performed by Natural Resources Wales (formerly the Countryside Council for Wales ). In the Isle of Man the role is performed by the Department of Environment, Food and Agriculture . Geological SSSI/ASSIs are selected by a different mechanism to biological ones, with a minimalistic system selecting one site for each geological feature in Great Britain. Academic geological specialists have reviewed geological literature, selecting sites within Great Britain of at least national importance for each of

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4524-424: The eggs singly in each puncture they make. Dragonfly nymphs vary in form with species, and are loosely classed into claspers, sprawlers, hiders, and burrowers. The first instar is known as a prolarva, a relatively inactive stage from which it quickly moults into the more active nymphal form. The general body plan is similar to that of an adult, but the nymph lacks wings and reproductive organs. The lower jaw has

4611-491: The end of the abdomen enabling them to draw in clean water while they are buried in mud. Naiads can forcefully expel a jet of water to propel themselves with great rapidity. Many adult dragonflies have brilliant iridescent or metallic colours produced by structural colouration , making them conspicuous in flight. Their overall coloration is often a combination of yellow, red, brown, and black pigments, with structural colours. Blues are typically created by microstructures in

4698-461: The exposure becomes obscured, the feature could in principle be re-exposed elsewhere. Conservation of these sites usually concentrates on maintenance of access for future study. Deposit sites are features which are limited in extent or physically delicate—for example, they include small lenses of sediment , mine tailings , caves and other landforms . If such features become damaged they cannot be recreated, and conservation usually involves protecting

4785-504: The feature from erosion or other damage. Following devolution, legal arrangements for SSSIs (Scotland, England, Wales) and ASSIs (Northern Ireland) differ between the countries of the UK. The Isle of Man ASSI system is a separate entity. NatureScot publishes a summary of the SSSI arrangements for SSSI owners and occupiers (other than public bodies) which can be downloaded from its website. Legal documents for all SSSIs in Scotland are available on

4872-429: The female behind the head using a pair of claspers on the terminal segment. In females, the genital opening is on the underside of the eighth segment, and is covered by a simple flap (vulvar lamina) or an ovipositor , depending on species and the method of egg-laying. Dragonflies having simple flaps shed the eggs in water, mostly in flight. Dragonflies having ovipositors use them to puncture soft tissues of plants and place

4959-454: The female lays eggs by tapping the surface of the water repeatedly with her abdomen, by shaking the eggs out of her abdomen as she flies along, or by placing the eggs on vegetation. In a few species, the eggs are laid on emergent plants above the water, and development is delayed until these have withered and become immersed. Dragonflies are hemimetabolous insects; they do not have a pupal stage and undergo an incomplete metamorphosis with

5046-515: The frontal hemisphere of the dragonfly. The compound eyes meet at the top of the head (except in the Petaluridae and Gomphidae, as also in the genus Epiophlebia ). Also, they have three simple eyes or ocelli. The mouthparts are adapted for biting with a toothed jaw; the flap-like labrum , at the front of the mouth, can be shot rapidly forward to catch prey . The head has a system for locking it in place that consists of muscles and small hairs on

5133-446: The gills of gravid freshwater mussels. Adults capture insect prey in the air, making use of their acute vision and highly controlled flight. The mating system of dragonflies is complex, and they are among the few insect groups that have a system of indirect sperm transfer along with sperm storage, delayed fertilisation, and sperm competition. Adult males vigorously defend territories near water; these areas provide suitable habitat for

5220-579: The head, thorax, and abdomen, as in all insects. It has a chitinous exoskeleton of hard plates held together with flexible membranes. The head is large with very short antennae . It is dominated by the two compound eyes, which cover most of its surface. The compound eyes are made up of ommatidia , the numbers being greater in the larger species. Aeshna interrupta has 22650 ommatidia of two varying sizes, 4500 being large. The facets facing downward tend to be smaller. Petalura gigantea has 23890 ommatidia of just one size. These facets provide complete vision in

5307-405: The interest), but not illegal trail biking. This loophole was closed by the Countryside and Rights of Way Act 2000 and section 19 of the Nature Conservation (Scotland) Act 2004. Funding for the monitoring of SSSIs in England has been cut from £1.58 million in 2010 to £700,000 in 2018, causing concern that many have not been inspected over the last six years, as required by guidelines. Since

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5394-473: The interested parties and allow a period for them to make representations before confirming the notification. When creating a new SSSI/ASSI the designation has legal effect from the date of notification. The interested parties include central government, local planning authorities , national park authorities, all the owners and occupiers of the land, relevant public bodies such as the utility providers e.g., water companies . In Scotland, NatureScot must also notify

5481-464: The intertidal land down to mean low water spring or to the extent of the local planning authority area, thus only limited areas of estuaries and coastal waters beyond MLWS may be included. In England, Natural England may notify an SSSI over estuarial waters and further adjacent waters in certain circumstances (section 28(1A & 1B) of the Wildlife and Countryside Act 1981 as amended by Part 2 of Annex 13 of

5568-402: The list for an SSSI will only omit activities impossible on the particular SSSI (such as fishing where there is no water), and things requiring planning permission (which are covered by the local planning authority consultation process). In Scotland, and following the implementation of the Nature Conservation (Scotland) Act 2004, Scottish Natural Heritage (the former name for NatureScot) reviewed

5655-592: The male grasps the female at the back of the head, and the female curls her abdomen under her body to pick up sperm from the male's secondary genitalia at the front of his abdomen, forming the "heart" or "wheel" posture. Fossils of very large dragonfly-like insects, sometimes called griffinflies , are found from 325 million years ago (Mya) in Upper Carboniferous rocks; these had wingspans up to about 750 mm (30 in), though they were only distant relatives, not true dragonflies which first appeared during

5742-428: The male may help to pull her out of the water. Egg-laying takes two different forms depending on the species. The female in some families (Aeshnidae, Petaluridae) has a sharp-edged ovipositor with which she slits open a stem or leaf of a plant on or near the water, so she can push her eggs inside. In other families such as clubtails (Gomphidae), cruisers (Macromiidae), emeralds (Corduliidae), and skimmers (Libellulidae),

5829-519: The most important features within each geological topic (or block ). Each of these sites is described, with most published in the Geological Conservation Review series, and so becomes a GCR site . Almost all GCR sites (but no other sites) are subsequently notified as geological SSSIs, except some that coincide with designated biological SSSI management units. A GCR site may contain features from several different topic blocks, for example

5916-439: The most northerly of all dragonflies. Dragonflies (suborder Anisoptera) are heavy-bodied, strong-flying insects that hold their wings horizontally both in flight and at rest. By contrast, damselflies (suborder Zygoptera) have slender bodies and fly more weakly; most species fold their wings over the abdomen when stationary, and the eyes are well separated on the sides of the head. An adult dragonfly has three distinct segments,

6003-400: The natural and artificial processes which resulted in their development and survival, for example the continued traditional grazing of heathland or chalk grassland . In England, the designating body for SSSIs, Natural England , selects biological SSSIs from within natural areas which are areas with particular landscape and ecological characteristics, or on a county basis. In Scotland,

6090-979: The new Act, often with boundary changes. This complex process took some ten years to complete for the several thousand SSSIs. For the purposes of selecting the original tranche of SSSIs, Natural England's predecessors (the Nature Conservancy, the Nature Conservancy Council and English Nature ) used a system termed "areas of search" (AOSs). In England these were largely based on the 1974–1996 administrative counties (with larger counties divided into two or more areas), whereas in Scotland and Wales they are based around districts. The individual AOSs are between 400 km (150 sq mi) and 4,000 km (1,500 sq mi) in size. There were 59 AOSs in England, 12 in Wales, and 44 in Scotland. Watsonian vice-counties were formerly used for selection over

6177-399: The notification is then confirmed or withdrawn (in whole or part). At the time of the passing of the Wildlife and Countryside Act 1981 , many SSSIs were already in existence, having been notified over the previous decades under the National Parks and Access to the Countryside Act 1949 . Each of these was considered in turn, and either denotified, or renotified —brought under the provisions of

6264-482: The nymphal stage lasts up to five years, and the adult stage may be as long as 10 weeks, but most species have an adult lifespan in the order of five weeks or less, and some survive for only a few days. They are fast, agile fliers capable of highly accurate aerial ambush, sometimes migrating across oceans, and often live near water. They have a uniquely complex mode of reproduction involving indirect insemination, delayed fertilisation, and sperm competition . During mating,

6351-403: The nymphs to develop, and for females to lay their eggs. Swarms of feeding adults aggregate to prey on swarming prey such as emerging flying ants or termites. Dragonflies as a group occupy a considerable variety of habitats, but many species, and some families, have their own specific environmental requirements. Some species prefer flowing waters, while others prefer standing water. For example,

6438-447: The owners and occupiers of SSSIs. Previously, activities by "third parties" were not illegal under the SSSI legislation. This meant that damaging activities such as fly-tipping , intensive bait-digging or trail biking on an SSSI were only prevented if done (or permitted) by the owner or occupier – not if done by trespassers or under public rights. The effect was, for example, to allow control of legal trail biking on SSSIs (where damaging to

6525-468: The poetry of Lord Tennyson and the prose of H. E. Bates . The infraorder Anisoptera comes from Greek ἄνισος anisos "unequal" and πτερόν pteron "wing" because dragonflies' hindwings are broader than their forewings . Dragonflies and their relatives are similar in structure to an ancient group, the Meganisoptera or griffinflies, from the 325  Mya Upper Carboniferous of Europe,

6612-517: The proposed operation and may, for example, limit its timing, location or intensity. The process is slightly different where the owner or occupier is a public body, but the effect is broadly similar. The relevant nature conservation body sends all SSSI owners and occupiers a site-specific 'site management statement' describing the ideal management (there may be grants available to help fund management). Owners and occupiers are encouraged to carry out this management, which in many (but not all) cases will be

6699-557: The referendum to leave the EU in 2016, more than 450 staff have been transferred to the Department for Environment, Food and Rural Affairs (Defra). Neglected areas include Exmoor , the Lake District , the Pennines , and The Wash . The process of designating a site as of Special Scientific Interest is called notification; this is followed by consultation with the site's owners and occupiers, and

6786-560: The relevant community councils and community group having registered an interest in the land. The notification includes a description of the land and the natural features for which it is notified ("the citation"), a boundary map, and a list of the acts or omissions (activities) that the nature conservation body regulates through the issue of consents. The various laws protect the interest features of SSSIs from development, from other damage, and (since 2000 in England) also from neglect. Protection

6873-761: The site is managed by the Royal Society for the Protection of Birds , and a small area is Wrabness Nature Reserve , a Local Nature Reserve managed by the Essex Wildlife Trust . The estuary is nationally important for thirteen species of wintering wildfowl and three on autumn passage, for coastal saltmarsh, sheltered muddy shores, two scarce marine invertebrates, scarce plants and three geological sites. Birds include redshank , black-tailed godwit and dunlin , and there are nationally important sponges, ascidians and red algae . Harwich has thirty ash layers dating to

6960-411: The spermatheca at any time. Males use their penis and associated genital structures to compress or scrape out sperm from previous matings; this activity takes up much of the time that a copulating pair remains in the heart posture. Flying in tandem has the advantage that less effort is needed by the female for flight and more can be expended on egg-laying, and when the female submerges to deposit eggs,

7047-472: The thermal death point of insects of the same species in cooler places. Dragonflies live from sea level up to the mountains, decreasing in species diversity with altitude. Their altitudinal limit is about 3700 m, represented by a species of Aeshna in the Pamirs . Dragonflies become scarce at higher latitudes. They are not native to Iceland , but individuals are occasionally swept in by strong winds, including

7134-403: The underside of the second segment has a cleft, forming the secondary genitalia consisting of the lamina , hamule, genital lobe, and penis. There are remarkable variations in the presence and the form of the penis and the related structures, the flagellum , cornua, and genital lobes. Sperm is produced at the 9th segment, and is transferred to the secondary genitalia prior to mating. The male holds

7221-561: The water, including its trophic status (degree of enrichment with nutrients) and pH can also affect its use by dragonflies. Most species need moderate conditions, not too eutrophic , not too acidic; a few species such as Sympetrum danae (black darter) and Libellula quadrimaculata (four-spotted chaser) prefer acidic waters such as peat bogs, while others such as Libellula fulva (scarce chaser) need slow-moving, eutrophic waters with reeds or similar waterside plants. Many dragonflies, particularly males, are territorial . Some defend

7308-575: The wetlands to lay their eggs or to find mating partners. Unwanted mating is energetically costly for females because it affects the amount of time that they are able to spend foraging. Dragonflies are powerful and agile fliers, capable of migrating across the sea, moving in any direction, and changing direction suddenly. In flight, the adult dragonfly can propel itself in six directions: upward, downward, forward, backward, to left and to right. They have four different styles of flight. The wings are powered directly , unlike most families of insects, with

7395-778: The whole of Great Britain. Dragonfly A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata . About 3,000 extant species of dragonflies are known. Most are tropical , with fewer species in temperate regions . Loss of wetland habitat threatens dragonfly populations around the world. Adult dragonflies are characterised by a pair of large, multifaceted, compound eyes , two pairs of strong, transparent wings , sometimes with coloured patches, and an elongated body. Many dragonflies have brilliant iridescent or metallic colours produced by structural coloration , making them conspicuous in flight. An adult dragonfly's compound eyes have nearly 24,000 ommatidia each. Dragonflies can be mistaken for

7482-492: The wing bases. Some aeshnids such as the brown hawker ( Aeshna grandis ) have translucent, pale yellow wings. Dragonfly nymphs are usually a well- camouflaged blend of dull brown, green, and grey. Dragonflies and damselflies are predatory both in the aquatic nymphal and adult stages. Nymphs feed on a range of freshwater invertebrates and larger ones can prey on tadpoles and small fish . Naiads of one species, Phanogomphus militaris , may even act as parasites, feeding on

7569-652: The wing for several months, but this may represent a whole series of individuals, with new adults hatching out as earlier ones complete their lifespans. The sex ratio of male to female dragonflies varies both temporally and spatially. Adult dragonflies have a high male-biased ratio at breeding habitats. The male-bias ratio has contributed partially to the females using different habitats to avoid male harassment. As seen in Hine's emerald dragonfly ( Somatochlora hineana ), male populations use wetland habitats, while females use dry meadows and marginal breeding habitats, only migrating to

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