Lyons, tigers and bare ground
Posted by Graeme Lyons , Thursday, 2 May 2013 13:58
Many of you will be familiar with the common Green Tiger Beetle Cicindela campestris but it has a much scarcer cousin, the Heath Tiger Beetle Cicindela sylvatica which probably went extinct in Sussex several decades ago. This species is a Biodiversity Action Plan species and is nationally scarce (Na) with the major population centres being the New Forest and Surrey Heaths. The last unconfirmed sighting in Sussex was at Iping in the 1980s, so it was decided that this would be a good place to reintroduce it. Often confusingly called the Wood Tiger Beetle, this species is very much restricted to lowland heathland and is not really a woodland species. Here it is again in all its glory.
And the smaller and more brightly coloured Green Tiger for comparison.
Prior to the reintroduction, the reason the species went extinct on the site needed to be addressed first. This was loss of bare ground and pioneer heathland. We create this at Iping in a number of ways such as burning, scraping and turf-stripping but it is the turf-stripping that seems to produce the best results for the Heath Tigers and a suite of other scarce invertebrates. In 2007, six females were introduced followed by a further 16 in 2009. The species has been recorded annually in small numbers each year since then and would appear to now be established on site. Turf-stripping is carried out annually to ensure that there is always some suitable habitat and the turf is sold on to golf courses whereby new heathland is created there. Everyone is a winner! Here is the small turf-stripped area I saw the Heath Tiger on, immediately adjacent to the original release site.
When I came to write up this work over the winter, it became clear that we hadn't been keeping track of where and when this management had occurred so I went out there on the 1st May to digitally map and 'age' the scrapes. I also wanted to see what else was benefiting from the management. Heath Tiger emerges a little later in the year than Green so I was surprised to see one. I kept hold of it for an hour or so to cool it down and show the volunteers and it kept still enough to allow the above shots. Proof that the Coolpix 4500 consistently produces good macro shots! Not bad for a ten year old camera.
I picked up a few carabids on the turf-stripped areas but it wasn't until this morning that I realised that the Pterostichus I had picked up on one area only put in this winter was in fact the Heath Short-spur Anisodactylus nemorivagus! This generic looking carabid has as many letters after its name as the Heath Tiger Beetle (BAP and Na) and would appear to be only the third Sussex and second West Sussex record! I trapped it in a pitfall trap at Graffham Common in 2009 and Mark Telfer identified it. Peter Hodge also pitfall-trapped it in Ashdown Forest. This means that I am the only person to have seen this beetle alive in Sussex!
Anyway, after mapping and monitoring 55 turf-stripped scrapes, I recorded about 90 Green Tigers to my one Heath Tiger but it is still early in the season so I hope to see more spreading around the site later in the year.
Birds were good too with a singing Redstart in the same place it was recorded last year and a Hobby catching bumblebees on the wing.
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