During a couple of very cold days in early December 2017 I trotted off to Castle Marshes in North Cove along with our Assistant Warden and my fellow volunteers and pals J and R. Our mission: to look for, and rehome in the dykes, fen raft spiders (FRS) that had been displaced by the dredging of the dykes.
Every year, the dykes need to be dredged to recreate a channel of water. A digger moves along the bank and lifts out the mud, sunken water soldiers (that the FRS lives on), and grass and sedge that has begun to encroach on the water. Without the dredging, the dyke would gradually fill, eventually becoming a continuous part of the surrounding land. The aquatic environment would be lost, along with all its denizens.
If the spiders are left in the debris, they risk being crushed by the digger, which flattens the debris the day after the dredging; they also risk being eaten by herons and other hungry predators. Our efforts would have mitigated that risk, even if only a little. Every spider saved means potentially hundreds to hatch the following year.
The digger starts its work
Picking through the debris
You can see the massive encroachment onto the dyke beyond the clear water, where the digger has stopped.
R was very clever and found 11 FRSs over the two days. I found not a single one, despite the the cold numbness in my fingers and the developing sciatica in my left leg. Neither did J. Harrumph!I managed to find only minute specimens of probably every other arachnid species in the dyke. I have no idea how R managed it -better eyesight and keener to throw herself into the mud than me I expect. We were not helped by the ambient temperature of 5 Celsius, causing all the insects and spiders to be very torpid -not moving around meant they were harder to spot.
Finding a FRS in the weeds and mud. You can see its brown legs poking out a little below the pointing index finger.
One for the pot. But not for cooking -he was put back into the water nearby to live on and, with luck, breed next year.
However I was delighted to find a couple of large and very handsome great diving beetles. Click here for more information on this beautiful insect, Dytiscus marginalis.
Hello! I think I must be having an out-of-water experience. I can see a bright light….
Beautiful green iridescence on his head
A formidable and well-equipped hunter
While we were out on Castle Marshes, a Chinese water deer was startled and ran away from us.
Big round Mickey Mouse ears and a pair of tusks
Bounding away
One of the last things we saw that day was the spectacular rise of a flock of Greylag Geese, disturbed by something or someone, wheeling across the sky and cackling en masse. I’ve tried to discover if there is another collective noun for a number of geese in flight, and can’t find agreement amongst different sources. Here is a selection -take your pick: flock, plump, skein, team, wedge, gaggle.
This video is a little shaky -no time to get my Monopod which was 20 feet away in the mud. Still, I’m pleased with my amateur efforts on a handheld bridge camera.