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Showing posts from May, 2019

Rock Pipit in Dorset: what your tweets tell us ...

Rock Pipit in Dorset: what your tweets tell us ...

The rock pipit is aptly named; it is a member of the pipit family and is found only around rocky shores. Given Dorset has rocky shores almost continuously from from Ballard Down north of Swanage in the east to Lyme Regis west it is not surprising that the rock pipit can be frequently seen here. Due to its specific habitat preference restricting its distribution it is not a species you will encounter readily unless you go to the right locations and in those places it can be quite easily found although it does not occur in big numbers anywhere. Superficially it looks quite similar to many of the other pipit species so it is this affinity to rocky shore lines that help set it apart and identifiable. The rock pipit is a resident British species and does not migrate and they usually stay in the same location all year round. The weekly reports chart from your tweets seems to tell a slightly different story however. There are reports every wee…

Grey wagtail in Dorset: what your tweets tell us ...

Grey wagtail in Dorset: what your tweets tell us ...

It is sad that I have to start most bird species reviews by saying that it is not as common as it once was but that is just the way things are as bird populations in general continue to decline despite best efforts of conservation organisations to stop the rot. The grey wagtail is yet another species that falls into the category of 'declining' having not so long ago been a familiar sight along the Dorset rivers and streams but are now seldom seen. Being an insect feeder the grey wagtail is associated with rivers, often by bridges or where there are stony outcrops above the water level, where they can wait and watch ready to fly out and catch any insect they espy. The grey wagtail is a resident breeding species in Dorset and despite being less common there are reports from most weeks of the year outside of gap from week week 22 to week 32, that is from early June to mid-August. I personally think that this reflects the decline …

Yellowhammer in Dorset: what your tweets tell us ...

Yellowhammer in Dorset: what your tweets tell us ...

Fifty years ago the yellowhammer was a fairly common sight around farmland where it nested in hedgerows and fed mainly on the seed dropped during the harvest season. The change to winter wheat in the 1970s and a trend to hedge removal to accommodate larger and improved harvesters meant that both nesting cover and food supply for the yellowhammer, and other farmland birds of course, were lost and the population started to decline. It is estimated that in those fifty years the yellowhammer population has fallen substantially, probably by more than 50%, and this species is now missing from farms and found mainly on areas of scrubby chalk or limestone grassland. A yellowhammer is now something of a chance encounter rather than a species one would expect to see. This is a resident breeding species in Dorset and the weekly reporting chart shows a small number of reports for most weeks of the year. There is possibly a trace of a small gap in…

Sparrowhawk in Dorset: what your tweets tell us ...

Sparrowhawk in Dorset: what your tweets tell us ...

I find it difficult to describe the status of the sparrowhawk in Dorset. It is far from common that is for sure but, that said, they are frequently seen although they can be somewhat elusive due to their hunting technique of flying silently, quickly and low along hedgerows and through gardens. During the middle of the last century, the 1950s and 60s in particular, numbers fell to dangerously low levels and this was linked to the use of DDT on farms affecting their food chain. Since DDT was banned numbers have recovered to a more secure level. There are people I have met who, amazingly I think, blame the decline of garden song birds on the rise of the sparrowhawk ... I despair sometimes! The sparrowhawk is a resident breeding species in Dorset and there are reports for most weeks during the year but strangely reports get a bit patchy from week 19 towards the end of May until week week 29 at the beginning of July; this is obviously durin…

Shelduck in Dorset: what your tweets tell us ...

Shelduck in Dorset: what your tweets tell us ...

Shelduck can be seen around the sheltered coastal waters of Dorset for most of the year. They breed here in small numbers and then are joined by inward bound birds from further north in the autumn to overwinter here. The shelduck has a particular habit of leaving its breeding territory in late summer to gather with many others of its kind to moult; there are established moulting sites and famously many thousands gather on part of the northern coast of Germany. There are some moulting sites on estuaries in Britain but there is not one in Dorset sadly. Overall the British population seems to be increasing and now they can be sometimes found breeding at sites inland. The weekly reporting chart based on tweeted observations shows the expected pattern based on the textbook description of their life cycle with records pretty continuously from week 1 to week 27 at the start of July by which time the young birds are able to travel. There is then …

Curlew Sandpiper in Dorset: what your tweets tell us ...

Curlew Sandpiper in Dorset: what your tweets tell us ...

The curlew sandpiper is an occasional autumn and spring visitor to Dorset, not uncommon but not a species you see everytime you go out with your binoculars! An Arctic breeding species, like so many waders, it has to migrate south when the severe weather sets in and the curlew sandpiper goes long distances to coastal regions of east and west Africa. There are, apparently, three routes they follow and one of those routes brings about a thousand of them to the North Sea coast of Britain so it is just a small number that end up as far west as Dorset. The number seen in Dorset seems to vary each year and I suspect that depends on weather conditions affecting the route they are trying to follow. The tweeted reports of curlew sandpiper show small numbers present from week 29 in July onwards into the autumn but reports certainly seem to pick up from week 36 in early September until week week 43 in late October an this peak undoubtedly tie…

Great Crested Grebe in Dorset: what your tweets tell us ...

Great Crested Grebe in Dorset: what your tweets tell us ...

The great crested grebe, like others in the group, are equally at home on fresh water and on the sea. They breed on freshwater lakes and occasionally on slow moving rivers and then, when the family is old enough in late summer, they relocate to sheltered harbours and bays. A small number breed on lakes and rivers in Dorset but in winter the numbers are swollen by birds from further north both in Britain and northern Europe. I am not sure we actually know where our few breeding pairs and their families go; maybe it's further south into mainland southern Europe and that all of our winter sightings are of birds from the north? In winter it is not unusual to see groups of six or more together although they are often spread out rather than being in a cluster. The weekly sightings from Twitter reports makes for interesting viewing. From week 14 in early April there are just one or two reports each week through until week 28 in mi…

Small Heath in Dorset: what your tweets tell us ...

Small Heath in Dorset: what your tweets tell us ...

The small heath is certainly a small species and that can help identify it from other browns. The underside of the wing is quite similar to the meadow brown and the gatekeeper so in this case size matters if it is at rest with its wings closed. The small heath has several overlapping broods each summer so the can be seen almost consistently from May right through until October in mainly grassy areas on downs, cliffs and heath. The small heath is probably the most common grassland species over the course of a summer but it may be outnumbered by Meadow Brown in mid-summer. Here in Dorset they start to emerge in week 18 which is around the second week in May. There is one report from week 16 in late April for 2017. There are then reports in most weeks through until week 43 at the end of October but there is a break three week break between broods from week 30 to 32 in July. The number of reports is greater in late summer than earlier in t…

Ringlet in Dorset: what your tweets tell us ...

Ringlet in Dorset: what your tweets tell us ...

It is just my perception, with no data to support it, that the ringlet may be being seen more frequently now than it was, say, thirty years ago. That said the Nature of Dorset database only has twenty records for 2017 and 2018 combined so it is one of the least reported of the more accessible butterflies; by that I mean that some species are hard to find because of their preferred habitat and so have few records. The ringlet is seen mainly in near lush vegetation in damp, shady areas in woodlands, along hedgerows and riverbanks. Being mainly dark brown with just a series of light brown rings on its underwings it cannot really be confused with any other species if seen at rest.  The reports we have for Dorset from tweeted sightings show emergence of the single brood in week 25 and ends in week 28; just a four week flight period around the latter part of June and in to early July. The textbooks agree on mid-June for first sightings but consi…

Meadow Brown in Dorset: what your tweets tell us ...

Meadow Brown in Dorset: what your tweets tell us ...

I do not have access to any figures from surveys but I suspect that the meadow brown is the most numerous and possibly most widespread butterfly in Dorset. They lay their eggs on various species of frequently found grasses and so where you find those grasses you will possibly find meadow browns and that is just about everywhere! It is very common on limestone and chalk grassland and we have quite a lot of that in Dorset but the meadow brown can also be found along woodland rides, on coastal dunes, by hedgerows and on road verges (unless they are the ones cut every other week by the Council) and areas of 'wasteland'. They are not that common in gardens though thanks to our lawn mowers and our desire to keep our grass cut short, assuming there is grass in the first place given the current trend to decking and paving. The database reports show the meadow brown taking flight in week 21 in late May but June produces the most report…

Gatekeeper in Dorset: what your tweets tell us ...

Gatekeeper in Dorset: what your tweets tell us ...

I always new this delightful little butterfly as the hedge brown; it is a member of the 'brown' family and is often found along hedgerows, especially hedges with brambles present. With name standardisation it is now known as the gatekeeper and I think that is a much more interesting name than the rather dull hedge brown. The gatekeeper is found in a wide range of habitat, not just hedgerows. You will find it along sunny woodland rides, in parks and gardens, on sea cliffs, scrubby grasslands and even heath. Whist they adore bramble they are happy on almost any nectar bearing flower including thistles and ragwort and in our garden they have a particular passion for marjoram. The reports we have in the Nature of Dorset database show the gatekeeper emerging in week 26, reports peak in week 27 and then continue every week until week 32 and then that is it for another year. This means they can be seen in Dorset from late June until la…

Grayling in Dorset: what your tweets tell us ...

Grayling in Dorset: what your tweets tell us ...

The grayling is considered to be a mainly coastal species favouring a variety of open habitat types from heath to limestone grassland. It does not seem to be a woodland species as it likes to sunbathe on dry, bare soil or rock and as such it can also be found in disused quarries and we have few of those here on the Dorset coast. It rarely rests with its wings open and when the wings are closed it can be incredibly well camouflaged and hard to spot; the first you see of it is when it suddenly taking flight as you pass close by its resting place. It also has the amazing ability to tilt to one side to reduce its shadow on the ground!  The Textbooks indicate that the grayling flies in July and August. Here in Dorset it seems to emerge in week 25 towards the end on June and then there are reports every week through until week 35 which is the first week in September. The most reports come in week 29 and July certainly seems the prime month for …

Marbled White in Dorset: what your tweets tell us ...

Marbled White in Dorset: what your tweets tell us ...

The marbled white is a brown; that is to say that it is a member of the family Nymphalidae to which many of our brown coloured butterflies belong. To look at, of course, it bears little resemblance colourwise to its cousins being very definitely an attractive patchwork of black and white. This pattern marks them out from all other British species and they should not be confused with anything else. This is a butterfly of flower rich downland and grassy places and thrives in dry, hot conditions. They seem to have a particular liking for purple/mauve flowers and adore knapweeds and thistles and so chalk or limestone grassland is particularly suitable for them but they do also occur in woodlands, along railway lines and even roadsides and hedgerows. Where they do occur their population can often far outnumber other species. The marbled white is single brooded and flies from mid-June to mid-August. Our Dorset records suggest emergence her…

Wall in Dorset: what your tweets tell us ...

Wall in Dorset: what your tweets tell us ...

I always knew this butterfly as the wall brown but now it is just called the wall which is, in my view, a rather odd name! They certainly likes stone walls and can be seen sunning themselves and absorbing heat from the stones on days when it's not so warm. Its first love is an area of bare, sun-baked earth to rest on. The wall has declined considerably in central and southern England in recent years but here in Dorset we are treated to them along the coastal cliffs where conditions obviously still suit them. There are thirty six reports of wall in the Nature of Dorset database, interestingly just nine for 2017 but a big increase in 2018 to 27. That could mean population levels vary each year or it could just be down to reporting variations; this may become clearer over time. The reports come in two batches; from week 15 in the later part of April to week 22 towards the end of May. The second brood then emerge week 28 in mid-July and then …

Speckled Wood in Dorset: what your tweets tell us ...

Speckled Wood in Dorset: what your tweets tell us ...

There are always winners and losers I suppose. Several butterfly species have declined with the demise of coppicing but it is thought this may have actually benefited the speckled wood. The speckled wood is a woodland species first and foremost and is quite happy in shade where most other butterflies prefer not to venture for too long. As a result of this shade tolerance they have done well in overgrown coppices; this has led them to spread out along hedgerows and even into gardens and parks. I was also surprised to learn that they do better in cooler, wetter summers and the recent generally poor years for many butterflies may well have benefited the speckled wood. It is now certainly one of our most common species in Dorset although many people may have never heard of it! The speckled wood can have up to three overlapping broods a year and so can be seen almost continuously from late March to early November. The Nature of Dorset dat…

Marsh Fritillary in Dorset: what your tweets tell us ...

Marsh Fritillary in Dorset: what your tweets tell us ...

The marsh fritillary is yet another butterfly that is absent from much of Britain but that can be found in a number of places in Dorset. It is certainly not common here, nor is it anywhere, but careful habitat management means its seems to be holding its own and not suffering the declines of elsewhere in the country. Marsh fritillary is a bit of an odd name for this butterfly; it has the chequered wing patterns that fritillaries have but it is not found in marshes. It does like damp, flower rich meadows where devil's-bit scabious grows but it also can be found on dry downland slopes that are far from being 'marshy'.  The marsh fritillary is single brooded and the books say it emerges in Mid-May and can be seen until mid-July. The records we have so far in the Nature of Dorset database would indicate a much shorter season starting in week 19 which is mid-May but there are no reports after week 23 in mid-June. The most p…

Silver-washed Fritillary in Dorset: what your tweets tell us ...

Silver-washed Fritillary in Dorset: what your tweets tell us ...

When seen in a woodland setting the silver-washed fritillary is unmistakable as it is a large, bright orange butterfly that cannot really be confused with any other species found in this habitat. This is true in Dorset I believe as the pearl-bordered fritillary is no longer found in Dorset woodlands having faded out here some years ago. The pearl-bordered may have been subject to a sad demise but thankfully the silver-washed is doing alright and is certainly holding its own for the time being at least. It should be born in mind that there is a darker form of silver-washed, the valezina form, which can be encountered and at first sight looks a totally different species!  The thirty eight reports of silver-washed fritillary in the Nature of Dorset database for 2017 and 2018 combined show that the first of these butterflies can be seen in week 25 in mid-June and then they are reported every week for seven weeks until week 31 …

Dark Green Fritillary in Dorset: what your tweets tell us ...

Dark Green Fritillary in Dorset: what your tweets tell us ...

The dark green fritillary is not green, it is orange and brown like many of the other fritillary butterflies. The name is not a total falsehood though as if you look closely at one whilst nectaring with its wings closed you will see the underside of the wing is partially green; whether that is dark green is open to debate! In flight it may seem, at first, difficult to tell the dark green fritillary from the superficially similar silver-washed fritillary. However there two fundamental differences with nothing to do with colouration that will help point you in the right direction. Firstly, the dark green is a butterfly that is rarely seen away from flower-rich chalk or limestone grassland whereas the silver-washed is much more of a woodland species. Secondly, the dark green is a powerful; flyer and flies with a flap. flap. glide, flap, flap, glide ... I do not think I have ever seen that in any other butterfly. Sadly, there are…

Comma in Dorset: what your tweets tell us ...

Comma in Dorset: what your tweets tell us ...

With its rather irregular, almost ragged, wing edges the comma is unique in appearance and familiar to many as they freely venture into shrubby parks and gardens although their main habitat is broadleaf woodland where they can be seen patrolling woodland rides and glades. The males are somewhat territorial and will attack any other male coming within their chosen patch; females however are made very welcome! Like others in the same family they hibernate over winter but will readily emerge on warmer winter days to feed and so may be seen at almost anytime of year apart from a break in June between first and second broods. Nettles form the food plant of the larvae and the second brood adults are very often seen around brambles and enjoy blackberries. Apart from one report in week 8 in February and one in week 43 in October the records in the Nature of Dorset tweets database show emergence of the comma from hibernation in week 11 towards the en…

Peacock in Dorset: what your tweets tell us ...

Peacock in Dorset: what your tweets tell us ...

With its distinctive wing colouration and 'eye' markings, as well as being a regular visitor to gardens, the peacock must surely be one of our best known butterflies. It is a resident breeding species in Britain laying eggs on common nettle and its black, spikey caterpillars are a common site munching their way through nettle leaves totally immune to any stinging that we suffer if we touch them. It is not just a garden butterfly of course, it can be encountered almost anywhere there are nectar rich flowers to feed on and that includes woodlands, scrub, heath and grassland. This is a hibernating species and so it can potentially be seen at almost anytime of year with a break around June between broods. The weekly reports chart shows sightings from week 6 in February continuously through until week 18 in late May. Then follows the inter-brood wait with virtually no reports until week 24 in early July. Then follows continuous reports …

Small Tortoiseshell in Dorset: what your tweets tell us ...

Small Tortoiseshell in Dorset: what your tweets tell us ...

The small tortoiseshell is another butterfly species whose fortunes are closely linked to those of its nemesis, in this case a parasitic fly Sturmia bella. In good population years for the butterfly the parasitic fly has ample caterpillars to lay its eggs in to and so the fly prospers at the expense of the butterfly and so numbers of the small tortoiseshell fall meaning less caterpillars for Sturmia bella and so its population level falls allowing more butterflies to emerge and so it goes on. That said, the population of small tortoiseshells seems to have fallen in recent years and it is far less common than it once was; well that is so in our garden anyway and this is a butterfly very much at home in gardens where it is quite comfortable feeding on various cultivated varieties of daisies and other flowers. As a butterfly that hibernates they can be seen at almost anytime of the year as they will emerge on milder days in winter…

Painted Lady in Dorset: what your tweets tell us ...

Painted Lady in Dorset: what your tweets tell us ...

The painted lady is a close relative of the red admiral appearing to have similar wing markings with the main difference being the painted lady is much paler, more orange than red. Closer inspection shows the two species to be quite distinct from each other despite initial thoughts of similarity. Like the red admiral the painted lady is a migrant species here in Britain and people seem much more aware about the migration of the painted lady than they do about the red admiral. The painted lady is much more varied in terms of numbers arriving and times of arrival compared to the red admiral. In some years there are very few painted ladies and in others the numbers can be almost overwhelming! There is also a tendency for the first painted lady influx to arrive later in the year than the red admiral; that said, no two years are the same when it comes to the painted lady. The first arrivals often land in July and then they can be seen rig…

Red Admiral in Dorset: what your tweets tell us ...

Red Admiral in Dorset: what your tweets tell us ...

The red admiral must be one of the most instantly recognisable of British butterflies; it is a familiar sight in gardens, parks and open countryside. It is so familiar that one would think this was a resident species but it is not, it is a migrant arriving in May and June having travelled from north Africa. These early arrivals lay eggs once they arrive and these hatch in to adults later in the summer but numbers are also continually boosted by new arrivals, especially in late summer, and it is from late August through until October that they seem to be most numerous. There is some evidence to suggest that some return back across the channel to mainland Europe as the autumn turns to winter, other succumb to the severe winter conditions and some find sheltered places to hibernate. These hibernating insects will often awake on warmer days in winter and that accounts for why you can actually see them in even January and February. The red …

White Admiral in Dorset: what your tweets tell us ...

White Admiral in Dorset: what your tweets tell us ...

Whilst the white admiral is not a common butterfly it is widespread in Dorset where the right habitat exists. It is a butterfly that likes sunny broadleaf woodland glades and rides and that is not a particularly frequent habitat type in Dorset. Where it does occur it is rarely seen in large numbers as it spends a lot of its time feeding on aphid honeydew in the upper branches of deciduous trees but it can be seen, usually the males, flying at lower levels patrolling their patch. Honeysuckle is the usual food plant chosen for the larvae. The books suggest that the first adults emerge in mid-July and fly until the end of August. Reports here in Dorset show week 24 as the earliest they are seen and that is fairly early in July. There are then reports for every week up to week 29 and that is in mid August. The bulk of the fairly few records we have come from weeks 25 to 27 in the latter half of July and the white admiral seems to have qu…