Sunday, August 26, 2018

In search of the Cliff comber

I've been wanting to go and have a look for a certain carabid beetle for a couple of years now and a last week I finally got my arse in gear and organised an after work trip with fellow beetler, Bill. Leaving home at 17.45 we arrived at Overstrand in NE Norfolk an hour before dusk (19:30).

The beetle in question was Nebria livida sometimes known as the Cliff Comber, a large and predatory ground beetle and a specialist of soft rock cliffs. Historically known from Norfolk to East Yorkshire it only appears to be hanging on on the soft cliffs either side of Cromer.

After beating a patch of Sea Buckthorn and attracting the attention of a couple of holidaying families who asked us what we were doing, we made our way down to the beach and headed east.

The habitat here is fairly dynamic with parts of the cliff collapsing each year, yielding new patches of bare clay. Other parts are quite well vegetated having had a number of years for plants to establish. There were also numerous fresh water seeps coming out the base of the cliff and it was here we would focus our search. 

Over the next 4 hours we found various beetles including Asaphidion pallipes, Platyderus depressus, Paranchus albipes and several species of Bembidion.....but no livida.

By 23:30 we were tired and still had a long drive home so we decided to call it a day.

We both felt like it needed another go, so last week saw a repeat trip out but this time to East Runton. The cliffs are steeper and there are far less water seeps and this time the weather was looking beautifully ominous.

However, after about 90 minutes of searching we came across a couple of isolated water seeps and lo and behold our quarry was there, hanging out at the top of the beach around these damp patches, waiting for whatever these beetles feed on.

They were absolutely stunning creatures and we counted at least 11 individuals over the next 20 or so minutes. It's good to see this species still hanging on here but the longer term forecast for them is less rosy. How much longer will they hang on.....

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