Storm Desmond hit Hauxley Nature Reserve hard. The immediate
problem in mid-December 2015 was the flowing across the main road in into the field
with the little experimental ponds we dug out in 1994. The deluge cut off the
reserve, right in the middle of the new build. The car park was just about
accessible in a 4x4 though a hovercraft was probably the best bet. Here is a
photo, from the Wildlife Trust, looking back along the road with the flood waters spilling over into the
field on the right,home to the little ponds.
At the time we thought the waters would recede. The field by
the entrance has flooded before, even at unlikely times such as the early summer
of 1997 when an intense rain storm hit just when the little experimental ponds
would normally dry up. They didn’t dry for another two years and changed markedly.
The plants and animals that like a bit of drying out were much scarcer and
instead thick blankets of green algae took over. A couple of years later, once
the ponds had dried out again in the summer of 1999o the algae disappeared.
Animals and plants benefit from the disturbance caused by drying, creatures like
pea shrimps (Ostracoda) or rarer algae such as the stoneworts (Chara) re-appeared, maybe from drought
resistant eggs or, in the case of Stoneworts, oospores in the mud, activated by
desiccation.
Storm Desmond seems to have changed the field. Six
months on and it is still almost completely flooded over. Here are two views
from the middle of the field back to the road, across the ponds. Firstly July 2012, a very wet year, but no total flooding. On the right, the same view July
2016.
The water is not falling which begs the question is it being
topped up somehow? More pressing for the wildlife are the impacts. Gone is the
lush, flower strewn high summer wet meadow. Instead spike rush (Eleocharis palustris) is one of the few
obvious survivors and the reeds from the pond to the side of the field have pushed
out two bridge heads, their advance guard visibly snaking out into the flood.
One extreme event has reset the ecology of the whole
pond system.
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