Thursday 8 July 2010

Sign of the times: Summer #6

More comparisons between the British countryside of today and that from 1959-1961 in the paintings of Charles Tunnicliffe in the Ladybird "What to look for..." series of books.



"Deep in the sun-searched growths
the dragonfly
Hangs like a blue thread loosened from
the sky."

Dante Gabriel Rossetti, Silent Noon


(Copyright: Ladybird Books)

Summer Picture 6
Still on the pond for this picture, we are on the pond surface with a lovely waterhen family, comprising a mother bird and a brood of seven chicks. They are swimming through a bed of waterlilies, both native species, the Yellow water-lily (Nuphar lutea) and the White water-lily (Nymphaea alba). The pink flowers of the emergent water plant, amphibious bistort, are on display at the top of the picture, and a large dragonfly, the southern hawker (Aeshna cyanea), is hovering above the lily pads at the bottom of the picture.


I deliberately shunted coverage of the waterhen from an earlier Spring picture until now, as I thought that this picture was so delightful that this is where I wanted to write about this species in more detail. The waterhen (Gallinula chloropus, more commonly known as the moorhen outside of Scotland) is, along with the coot, the other commonly-seen member of the rail family in Britain, on lochs, ponds, lowland rivers, canals, lakes and gravel pits, where it feeds while walking across floating vegetation or on surrounding damp land. There may be 240,000 breeding territories in Britain. The British Trust for Ornithology provided the long-term trend in the waterhen population below:





The BTO says of the waterhen: “While the long-term CBC/BBS [Common Bird Census/ Breeding Bird Survey] trend is of shallow increase, much of the population increase took place before 1974, when WBS [Wetland Bird Survey] monitoring began, and may have been a recovery from heavy mortality during the cold winters of the early 1960s. On both CBC/BBS and WBS/WBBS [Wetland Breeding Bird Survey] evidence, there was decrease during the 1970s and 1980s, but this has been followed by a partial recovery. A decline in the number and quality of farmland ponds, and the spread of American mink Mustela vison, which is an important predator especially along watercourses, have been suggested as possible causes of decline.”

Overall, between 1967 and 2007, the waterhen population in Britain increased by 28%. Maybe the increase in suitable habitats through the creation of gravel pits and the cleaning up of historic water pollution has also contributed to the recovery but I am only speculating. The BTO also reports that, between 1968 and 2007, the laying date for the waterhen is five days earlier on average, a possible effect of a warming climate. To conclude, the waterhen/ moorhen is not currently regarded as being of any conservation concern in Britain or Europe.


The yellow water-lily (Nuphar lutea) grows in slow flowing rivers, as well as canals and lakes with moderate to high levels of nutrients in the water, and is capable of surviving disturbance as it has many leaves growing below the surface, as well as the floating pads, which probably explains why it thrives in canal environments. The New Atlas of the British and Irish Flora indicates that the distribution of this species has been stable since the original 1962 Atlas. The white water-lily (Nymphaea alba) is another native waterlily, but is less tolerant of disturbance as it doesn't have submerged leaves, only floating lily pads. It has been widely introduced in England and so its actual natural distribution isn't clear but at least it hasn't decreased in Scotland since the 1962 Atlas. In his "Flora Britannica", Richard Mabey records that the yellow water-lily has smaller fowers, held above the water on stalks, as seen above, and smells slightly of wine dregs, hence its nicknames of "brandy balls", or "brandy bottle". In the past, both water-lily species suffered from being collected from the wild for collection.

The amphibious bistort (Persicaria amphibia) is another widely distributed native water plant. This plant grows, sometimes in considerable quantity, in lakes, ponds, canals, slow-flowing rivers and ditches, is a lovely element of the British aquatic flora, and is widely distributed in Scotland, although largely absent from Wester Ross, Caithness and Sutherland and the central Highlands. The New Atlas records that there: "has been no appreciable change in the distribution of this species since the 1962 Atlas".


The inclusion in the picture of the beautiful southern hawker dragonfly (Aeshna cyanea) tells me that, like the pond in the previous picture, this pond (who knows, maybe it is meant to be the same pond?) is likely to be in southern Britain, as this is largely where this dragonfly species is found, although it has been found breeding in Scotland before. Its habitat is around ponds and lakes and it is usually seen as an adult from early June to early October (although, as in the previous picture, its larva spends maybe up to a couple of years as a ferocious underwater predator). The British Dragonfly Society has some excellent pictures of this dragonfly here. This web page says that this dragonfly species "hunts well away from water and may be found hawking woodland rides well into the evening".

4 comments:

  1. You're right - very nice photos on the BDS site.

    another interesting one SNB.

    cheers.....Al.

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  2. Thanks very much Al - much appreciated. Been away for a wee while down south (possible blog post to follow) so just trying to catch up with nature's relentless timetable!

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  3. These illustrations take me right back to childhood. Super blog.

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  4. Thanks a lot Rosie - that's very kind. Why not stick around - I'm taking this series right through Summer, into the Autumn and Winter books too! The pictures in these books were very important to me as a child too, as you can probably tell!

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