Doncaster Lakeside Spiders have a ‘Website’ in the spotlight
Introduction: Although spiders aren’t everyone’s cup of tea, the ones in residence under the road bridge which carries Lakeside Boulevard over the entrance to the Lakeside ‘Marina’ (SE595014), have turned out to be one of Lakeside’s wildlife highlights.
It is a waterside species, not of trees, bushes and water plants but of the built environment, preferring concrete, brickwork and metal structures and is particularly attracted to modern outdoor light fittings. In fact it is perfectly designed for the Lakeside environment.
Our spider has the rather unwieldy scientific name Larinioides sclopetarius but I think we could more appropriately call it the ‘Security light’ spider.
Species description: Related to the orb-web spinning Aranea spiders, it has a similar body shape to the familiar ‘Garden’ or ‘Cross’ Spider A. diadematus. It has a distinctly velvety appearance, and the dark markings of the head, carapace and abdomen are conspicuously highlighted by clear white, characteristically angular, outlining (Jones 1983 & Roberts 1995).
Status, distribution and behaviour: In Britain it is described as very locally distributed throughout England and Wales and generally rather uncommon (Jones 1983 & Roberts 1995). Across Yorkshire, Clifford Smith (1982 & 1985) described it as uncommon, being recorded from only eight 10km squares (SE/14; 42; 50; 61; 63; 64; 65; 71). These are mainly in lowland regions, six being within the Humber Head Levels natural area, three of which are in the Doncaster region. The most significant site apart from Lakeside is the rather splendid 160m long aqueduct carrying the New Junction Canal over the river Went and its adjacent soak drains (SE/6418; 6518) (Howes 1999).
The most noticeable populations at Lakeside are on the series of lighting panels either side of the bridge underpass. Here the very dense and tough webs are set to snare the millions of aquatic insects like mosquitoes, and mayflies which emerge from the water and are immediately attracted to the adjacent lights. The strong air flows, amplified by the funneling effect of the bridge structure will also concentrate an aerial plankton of insects across the toughened webs. Similar insect-festooned webs can be seen on the promenade lighting around the lake and the flood lights of the lofty Lakeside hotels and office blocks. Since such high air velocity is likely to destroy the webs of most other orb-web builders, the particularly tenacious silk of L. larinioides probably accounts for why this species dominates in these situations. It may also indicate a potential industrial application for the silk.
Although active all year round, they are more numerous and more active in mid to late summer. On 6 August 2012 there were approximately 200 adults occupying webs around and above the rows of lights which illuminate the bridge underpass, with dozens of cocoons protecting the eggs of the next generation, tightly attached to the underside of the concrete bridge structure.
How these recently built urban buildings and structures are so rapidly colonised is fascinating. The tiny ‘spiderlings’, freshly emerged from their cocoons, position themselves in a strong air-flow, they then extrude a filament of silk into the wind (like a kite), then let go. The wind disburses these little aeronauts to serendipitously colonise new structures down-wind. This technique of disbursal is called ‘Ballooning’.
Most species of spiders build their own webs and woe betides any other spider that comes near … even courtship has its hazards. These spiders are quite different and if disturbed will move from web to web without attracting aggression from their neighbours. Although colonial spiders do occur, this is extremely rare in the arachnid world.
Though the rather splendidly patterned females can grow to 14mm in length, the extremely scarce males (less than 1% of the population) are quite puny and insignificant … know the feeling!
Reports and images of the fascinating wildlife at Doncaster Lakeside Park is featured in the very attractive website of the Lakeside Wildlife Action Group
http://lakesidewildlifeactiongroup.weebly.com/
References
Jones, D. (1983) Country life guide to spiders of Britain and Northern Europe. Hamlyn, London.
Howes, C.A. (1999) Spiders get new web site: Larinioides sclopetarious (Clerck,
1757) at Sykehouse Aqueduct, S. Yorkshire. Newsletter of the British
Arachnological Society. 85: 6-7.
Roberts, M. J. (1995) Collins field guide, spiders of Britain and Northern Europe.
HarperCollins, London.
Smith, C. J. (1982) An atlas of Yorkshire spiders. Privately published, York.
Smith, C. J. (1985) Additions to an atlas of Yorkshire spiders. Privately circulated.
Howes, C.A. (2014) Doncaster Lakeside spiders have a ‘website’ in the spotlight. The Doncaster Naturalist 2 (4): 159-160.
Colin Howes