I thought I got as many as 15 White-fronted Geese, Anser albifrons, feeding in front of the hide, together with about 50 Greylags and a dozen or so Black-bellied Brent Geese, Branta bernicla bernicla. This time I was sure that there were a mix of adult and juvenile birds. Also a sparrowhawk I think, and a grey heron. On the fenceline behind there were about 50 Goldfinches fluttering about. Half a dozen swans and cygnets were scattered around, and a couple of white (farmyard?) geese.
Sunday, 3 November 2013
Saturday, 2 November 2013
Lightning visit to Muswell Manor Beach and the Brent Geese
On the way I thought I picked out a Mediterranean Gull from a dispersed group of Black-headed Gulls on the fields on the Leysdown Road before the planted wood. I stopped to have a peek at the Raptor Mound, and there was a probable female Marsh Harrier over the reed-bad of the Capel Fleet.
On the beach there were numerous Black-headed and Herring Gulls, together with a few Greater Black-backed Gulls. There were also Oystercatchers, Redshank, a couple of Godwits, and a Curlew.
But the birds I had really come to see, the Dark-bellied Brent Geese, Branta bernicla bernicla, from the Russian North Artic were also there, in small groups of half a dozen or more. They are said to breed mainly on the Taymyr Peninsula in the far, far North. They winter in the South East of England (50% of the World population), and France and Holland, and in the spring they gather in the WaddenSee and then migrate further North and East via stopping off sites particularly such as the White Sea and the Kanin peninsula, heading for the Taymyr peninsula, travelling thousands of miles altogether.
The white neck flashes on the necks, and the dark bellies, only a bit less dark than their uppersides, were clear, and the white rears showed well. All of the ones that I saw looked like adults. The number of young, I seem to remember, may perhaps be partly dependent on the number of lemmings, and the resulting predation choices by Artic Foxes. They are certainly quite inconsistent breeders year on year.
The population dropped drastically in the 30s through to the 50s, recovered into the 70s, and stabilised in the 90s, at about a quarter of a million birds.
The Brent Goose population is generally protected in Western Europe under the EU Birds Directive 79/409 and under various national legislation. Hunting is not currently permitted, except in some local regions. As a result of the recovery and further increase of population size, however, proposals have been made in some countries for a regulated harvest of Brent Geese.
The Brent Goose is a success story in modern conservation; as a result of protection on the wintering grounds, together with other factors such as feeding on agricultural land and the recovery of eelgrass beds, they recovered from a very low population level in the 1950s.
On the beach there were numerous Black-headed and Herring Gulls, together with a few Greater Black-backed Gulls. There were also Oystercatchers, Redshank, a couple of Godwits, and a Curlew.
But the birds I had really come to see, the Dark-bellied Brent Geese, Branta bernicla bernicla, from the Russian North Artic were also there, in small groups of half a dozen or more. They are said to breed mainly on the Taymyr Peninsula in the far, far North. They winter in the South East of England (50% of the World population), and France and Holland, and in the spring they gather in the WaddenSee and then migrate further North and East via stopping off sites particularly such as the White Sea and the Kanin peninsula, heading for the Taymyr peninsula, travelling thousands of miles altogether.
The white neck flashes on the necks, and the dark bellies, only a bit less dark than their uppersides, were clear, and the white rears showed well. All of the ones that I saw looked like adults. The number of young, I seem to remember, may perhaps be partly dependent on the number of lemmings, and the resulting predation choices by Artic Foxes. They are certainly quite inconsistent breeders year on year.
The population dropped drastically in the 30s through to the 50s, recovered into the 70s, and stabilised in the 90s, at about a quarter of a million birds.
The Brent Goose population is generally protected in Western Europe under the EU Birds Directive 79/409 and under various national legislation. Hunting is not currently permitted, except in some local regions. As a result of the recovery and further increase of population size, however, proposals have been made in some countries for a regulated harvest of Brent Geese.
The Brent Goose is a success story in modern conservation; as a result of protection on the wintering grounds, together with other factors such as feeding on agricultural land and the recovery of eelgrass beds, they recovered from a very low population level in the 1950s.
Friday, 1 November 2013
Low Tide at Cliffe
Had a look from the viewpooint South of Radar Pool and there were about 500 Lapwing, 600 teal, 4 Pintail, 20 Mallard, 20 Shoveller, 1 Avocet.
It was very pleasant to see the few Pintail, upending in the middle distance.
There were about 12 Greater Black-backed Gulls in the distance, with 1 Herring Gull with them I think. GBBs are the largest of the Gulls, monotypic, with about 17,000 UK breeding pairs, and about 75,000 birds over-wintering (BTO). There was a considerable expansion in the twentieth century (Fishing industry?), both in the UK and worldwide, but populations in the UK may have fallen back a little since. Pink legs may help to distinguish from the Lesser with its yellow legs. Individuals may live for more than 27 years.
I stopped by Crystal Lake on the way back, under threat of rain, and there were just a pair of Mallard, and a Moorhen.
It was very pleasant to see the few Pintail, upending in the middle distance.
There were about 12 Greater Black-backed Gulls in the distance, with 1 Herring Gull with them I think. GBBs are the largest of the Gulls, monotypic, with about 17,000 UK breeding pairs, and about 75,000 birds over-wintering (BTO). There was a considerable expansion in the twentieth century (Fishing industry?), both in the UK and worldwide, but populations in the UK may have fallen back a little since. Pink legs may help to distinguish from the Lesser with its yellow legs. Individuals may live for more than 27 years.
I stopped by Crystal Lake on the way back, under threat of rain, and there were just a pair of Mallard, and a Moorhen.
B & Q
I was so involved in watching the Black-headed Gull, Choirocephalus ridibundus, flying from the roof of B & Q, that I ignored the lady telling me my bacon butty was ready. The butty was a special treat to cheer me up after my visit to the Doctor, who wants to do further tests on my cough.
Post-script - might well have been acid reflux, so I cut down on the spicy foods, then started to lose serious amounts of weight, and no problems since (Jan 2015)!
Post-script - might well have been acid reflux, so I cut down on the spicy foods, then started to lose serious amounts of weight, and no problems since (Jan 2015)!
Sunday, 20 October 2013
Back at Cliffe with a possible Little Stint, thinking of Golden Plover
Made it to Cliffe about an hour before high tide, just in time to see many of the waders arrive off the Thames.
Great numbers of Avocet, Dunlin, Black-tailed Godwit, Redshank, Little Egret, Great Crested Grebe, Little Grebe, Black-headed Gull, Black-backed Gull, Herring Gull, Shoveller, Teal, Shelduck, Mallard, some Pintail.
One possible Little Stint actively feeding on the drier sand behind a large group of Dunlin.
Woodpigeon, Stock Dove, Woodpigeon, Robin, Blue Tit, Long-tailed Tit. Some warblers seen, possibly an autumn call of a Chiff-chaff.
It was very nice to see the Golden Plover on the edges of the pools. There were a number of the Grey Plover as well, looking tougher as they so often do, with their heavier bills. However the Golden Plover, Pluvialis apricaria, were my main interest today. These may be breeding in Northern Europe or Russia, but they could be from the uplands of the UK as well. The breeding in the UK might be regarded as somewhat on the edge of its range, and also slightly artificial as upland moorland is largely created by historic land management, but there has been quite a lot of research on the breeding ecology of these gorgeous birds. The UK population could be regarded as at the southern edges of its breeding range and particularly subject to potential warming and drying climate change, which could reduce food sources such as cranefly (Tipulid) larvae. In order to preserve this potentially threatened population, 9Pearce-Higgins, 2011) suggested thart efforts could be made to improve habitat, and thus breeding success, and reduce predation on the other hand.
One very interesting and unexpected feature - the males and females split incubation period in an interesting way: the males incubate during the day, while the females incubate at night.
The research has shown some rather odd features of this species' breeding ecology. When not incubating their eggs on moorland, the adults can often be found on neighbouring agricultural pasture fields rather than moorland, where they are likely to be feeding (perhaps) or resting for about half their time. This is however less true for the males. The average distance moved to the fields was about 2.7 km in the Sunderland study, with females flying further than males. Individual flocks of birds tended to show fairly strong faithfulness to their individual favourite fields, both within a year, and from year to year. Relatively few of the available fields were used for feeding, with those used tending to be large, old, with some cover of rushes Juncus spp., and grazed by sheep. Leatherjackets were possibly the favoured prey.
Although field size did not seem to determine whether fields were occupied or not, field size was correlated with the numbers of birds in an occupied field. Having wet flushes did seem to increase the popularity of a field being chosen, as did the sward kept short by sheep. The nature of the boundary did not seem to have much of an effect, although this might have been expected to have affected ease of predation. The number of molehills, as a proxy for earthworm numbers, was a good indicator of field attractiveness, (according to Whittingham et al, 2000).
Once the eggs hatch, the behaviour of the adults changes, and then they spend much motre time foraging on moorland.
It was estimated that there were about 2,000 pairs breeding in Caithness, of which about half would have been nesting in the Special Protection Area (declared because of the importance of this area for the total breeding population. The fields used while incubating need to be managed appropriately: Management of areas of pasture to maintain their suitability for feeding golden plovers should, in general, avoid ‘improvement’ in the sense typified by agricultural intensification (Wilson et al., 2005). Specifically, the following practices should be avoided: Draining; Application of pesticides to control tipulid larvae (cranefly larvae = leatherjackets); Ploughing and re-seeding with single palatable grass species; Application of inorganic fertilisers; Removal of grazing; Conversion to silage or hay crop.
Based on the apparent preferences of golden plovers, the following characteristics of fields should be maintained: Field size (although enlargement through removal of fences between fields should not have an adverse effect); Poor drainage (as revealed by at least some coverage of Juncus rushes); Multi-species grass community; Grazing regime to maintain a short sward less than 5 cm
Tipulid larvae abundance is also enhanced by the presence of a taller sward during the adult tipulid emergence period ( July – September); this is thought to be because taller grass prevents airborne laying females being blown away by the wind and hence encourages them to lay their eggs in a small area around their emergence site (McCracken et al., 1995; Bignal et al., 1996). Thus a grazing regime whereby livestock is put on to fields in late winter (to create a short sward) but is removed shortly before the adult tipulid emergence period begins in July (to allow a taller sward to develop and retain laying female tipulids) should create favourable conditions for feeding golden plover. In this context, fields used as ‘lambing parks’, especially where ewes and lambs (or other livestock after lambing has finished) are held until mid-June before being hefted to other areas, are likely to be favoured by golden plovers, assuming other field characteristics are compatible.
Clearly these practices should be targeted at those fields already known to be used by plovers, although, as noted earlier, identification and maintenance of suitable ‘alternative’ fields nearby should also be desirable. The proportions of all fields which are used by golden plover are so small (about 3% overall) that it should be feasible to strike a balance between maintaining sufficient suitable fields whilst still being compatible with any intensification deemed as necessary by farmers, although in some holdings the proportion of ‘plover fields’ may be locally greater. Maintenance of fields which are potentially or known to be suitable for golden plover should also benefit several other wader species which appear to have similar preferences.
The chicks obviously feed closer to the nest, and appear in NorthEast England to like patches of mixed heather and grasses, as well as wet areas. Mixed grazing of appropriate intensity to create the vegetation mosaic, as well as stopping up drains to create the wet areas, might therefore be very helpful in aiding their feeding, possibly primarily in Tipulids (according to Whittingham et al, 2001). In Swedish Lapland the pattern differed somewhat according to (Machin et al, 2001), where the chicks fed largely on Coleoptera but also first on Tipulids on more open areas, then switched (as these ran out (?)) to Bibionids in Willow Scrub a bit later, which might also have helped to protect them from predators.
Great numbers of Avocet, Dunlin, Black-tailed Godwit, Redshank, Little Egret, Great Crested Grebe, Little Grebe, Black-headed Gull, Black-backed Gull, Herring Gull, Shoveller, Teal, Shelduck, Mallard, some Pintail.
One possible Little Stint actively feeding on the drier sand behind a large group of Dunlin.
Woodpigeon, Stock Dove, Woodpigeon, Robin, Blue Tit, Long-tailed Tit. Some warblers seen, possibly an autumn call of a Chiff-chaff.
It was very nice to see the Golden Plover on the edges of the pools. There were a number of the Grey Plover as well, looking tougher as they so often do, with their heavier bills. However the Golden Plover, Pluvialis apricaria, were my main interest today. These may be breeding in Northern Europe or Russia, but they could be from the uplands of the UK as well. The breeding in the UK might be regarded as somewhat on the edge of its range, and also slightly artificial as upland moorland is largely created by historic land management, but there has been quite a lot of research on the breeding ecology of these gorgeous birds. The UK population could be regarded as at the southern edges of its breeding range and particularly subject to potential warming and drying climate change, which could reduce food sources such as cranefly (Tipulid) larvae. In order to preserve this potentially threatened population, 9Pearce-Higgins, 2011) suggested thart efforts could be made to improve habitat, and thus breeding success, and reduce predation on the other hand.
One very interesting and unexpected feature - the males and females split incubation period in an interesting way: the males incubate during the day, while the females incubate at night.
The research has shown some rather odd features of this species' breeding ecology. When not incubating their eggs on moorland, the adults can often be found on neighbouring agricultural pasture fields rather than moorland, where they are likely to be feeding (perhaps) or resting for about half their time. This is however less true for the males. The average distance moved to the fields was about 2.7 km in the Sunderland study, with females flying further than males. Individual flocks of birds tended to show fairly strong faithfulness to their individual favourite fields, both within a year, and from year to year. Relatively few of the available fields were used for feeding, with those used tending to be large, old, with some cover of rushes Juncus spp., and grazed by sheep. Leatherjackets were possibly the favoured prey.
Although field size did not seem to determine whether fields were occupied or not, field size was correlated with the numbers of birds in an occupied field. Having wet flushes did seem to increase the popularity of a field being chosen, as did the sward kept short by sheep. The nature of the boundary did not seem to have much of an effect, although this might have been expected to have affected ease of predation. The number of molehills, as a proxy for earthworm numbers, was a good indicator of field attractiveness, (according to Whittingham et al, 2000).
Once the eggs hatch, the behaviour of the adults changes, and then they spend much motre time foraging on moorland.
It was estimated that there were about 2,000 pairs breeding in Caithness, of which about half would have been nesting in the Special Protection Area (declared because of the importance of this area for the total breeding population. The fields used while incubating need to be managed appropriately: Management of areas of pasture to maintain their suitability for feeding golden plovers should, in general, avoid ‘improvement’ in the sense typified by agricultural intensification (Wilson et al., 2005). Specifically, the following practices should be avoided: Draining; Application of pesticides to control tipulid larvae (cranefly larvae = leatherjackets); Ploughing and re-seeding with single palatable grass species; Application of inorganic fertilisers; Removal of grazing; Conversion to silage or hay crop.
Based on the apparent preferences of golden plovers, the following characteristics of fields should be maintained: Field size (although enlargement through removal of fences between fields should not have an adverse effect); Poor drainage (as revealed by at least some coverage of Juncus rushes); Multi-species grass community; Grazing regime to maintain a short sward less than 5 cm
Tipulid larvae abundance is also enhanced by the presence of a taller sward during the adult tipulid emergence period ( July – September); this is thought to be because taller grass prevents airborne laying females being blown away by the wind and hence encourages them to lay their eggs in a small area around their emergence site (McCracken et al., 1995; Bignal et al., 1996). Thus a grazing regime whereby livestock is put on to fields in late winter (to create a short sward) but is removed shortly before the adult tipulid emergence period begins in July (to allow a taller sward to develop and retain laying female tipulids) should create favourable conditions for feeding golden plover. In this context, fields used as ‘lambing parks’, especially where ewes and lambs (or other livestock after lambing has finished) are held until mid-June before being hefted to other areas, are likely to be favoured by golden plovers, assuming other field characteristics are compatible.
Clearly these practices should be targeted at those fields already known to be used by plovers, although, as noted earlier, identification and maintenance of suitable ‘alternative’ fields nearby should also be desirable. The proportions of all fields which are used by golden plover are so small (about 3% overall) that it should be feasible to strike a balance between maintaining sufficient suitable fields whilst still being compatible with any intensification deemed as necessary by farmers, although in some holdings the proportion of ‘plover fields’ may be locally greater. Maintenance of fields which are potentially or known to be suitable for golden plover should also benefit several other wader species which appear to have similar preferences.
The chicks obviously feed closer to the nest, and appear in NorthEast England to like patches of mixed heather and grasses, as well as wet areas. Mixed grazing of appropriate intensity to create the vegetation mosaic, as well as stopping up drains to create the wet areas, might therefore be very helpful in aiding their feeding, possibly primarily in Tipulids (according to Whittingham et al, 2001). In Swedish Lapland the pattern differed somewhat according to (Machin et al, 2001), where the chicks fed largely on Coleoptera but also first on Tipulids on more open areas, then switched (as these ran out (?)) to Bibionids in Willow Scrub a bit later, which might also have helped to protect them from predators.
Sunday, 13 October 2013
A lightning look at Crystal Pool, Cliffe
A very brief look of a minute or two at Crystal Pool, as the rain clouds rolled towards us, revealed a Herring Gull on the old woodwork, and a male Mallard together with a male Pochard, the first one for me this winter! Fantastic!
As we reached the car after our brief outing, the heavens opened. Excellent timing!
As we reached the car after our brief outing, the heavens opened. Excellent timing!
Wednesday, 9 October 2013
Phyllonorycter species at Dene Park
Interesting to think about leafmines at this time of year.
I found some nice blotch mines on the upper surface of Hornbeam leaves at Dene Park this afternoon, which I thought must be mines of a Phyllonorycter species from their "general look". The most likely species should be Phyllonorycter esperella, (Goeze 1783), according to the pictures on the leafminer website. The species has an old synonym, Phyllonorycter quinnata, (Geoffrey, 1785).
Phyllonorycter esperella mines are generally found first in June, then again in September-October, specifically on Hornbeam, Carpinus betulus (L.). The young mines are roundish, on the upperside (generally unusual for a leaf-mine), usually centred over a side vein, silvery with brown speckles, and they then expand to be larger ovals, often substantially contracting the leaf beneath them as they do so. All these characters seem to fit very well the mines that I found today!
The adults emerge, like many other Phyllonorycters, first in May and then again in August as a second brood.
I don't think it could be Phyllonorycter tenerella, as although this species is found on Hornbeam, it is described as being on the underside of the leaf, from the midrib to the edge of the leaf, and quite narrow, generally between only two veins.
http://calderdalemoths.blogspot.co.uk/2008/09/phyllonorycter-tenerella-challange.html
Equally it is very unlikely (but not absolutely impossible) that it should be Phyllonorycter ulmifoliella, which normally feeds on the underside of Birch leaves. There is however one recorded instance of this species feeding on the upperside of Hornbeam leaves, noted in the Entomologists Record of early 2013 following the emergence of an adult from a mine collected in the autumn of 201.?
I also do not think it will be Phyllonorycter messaniella, as that is generally found on Oak, Beech or Sweet Chestnut, and less commonly on Hornbeam. On Beech and Hornbeam this species is found on the lower surface between two adjacent veins, with a sharp fold, so again this does not really fit the majority of mines found. However there was one mine, clearly different, and I thought it was most likely to be this! It started well out from the midrib, and finished well before the leaf margin, and fitted the pictures really quite well.
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