Crescent ghost

Me and Dom standing in the Crescent ghost, before excavation.  This is the oldest ghost pond we have resurrected so far, having been filled in around 1850.  Despite this, evidence of the former pond was still visible; a slight depression containing wetland vegetation (including rushes and sedges), not seen elsewhere in the field.
September 2013 – Me and Dom standing in the Crescent ghost, before excavation.  This is the oldest ghost pond we have resurrected so far, having been filled-in around the 1850’s. Despite its age, there was still evidence that this was once a pond; a slight depression in the field, containing wetland vegetation (including rushes and sedges), not seen elsewhere.
Digging the test pit - As with Original ghost, it was clear from the test pit when the old sediment layer had been reached.  What was different in this ghost was that a layer of sticks had been arranged on top of the old pond sediment (top left corner of photo), presumably to allow a cart to be wheeled into the pond when filling it in.
September 2013 –  Digging the test pit.  As with Original ghost, it was clear from the test pit when the old pond sediment had been reached. What was unusual in Crescent ghost was that a layer of sticks had been arranged on top of the old pond sediment (top left corner of photo), presumably to allow a cart to be wheeled into the pond when filling it in.
Sediment from Crescent ghost - you know you are digging up an old pond when you find this!  Snail shells and pea mussel shells were abundant in the sediment from Crescent and Original ghost, with the occasional pond weed leaf also being preserved.  The leaf in the bottom of this shot is from a willow tree.
September 2013 –  Sediment from Crescent ghost – you know you are digging up an old pond when you find this! Snail shells and pea mussel shells were abundant in the sediment from Crescent and Original ghost, with the occasional pondweed leaf also being preserved. The leaf in the bottom of this shot is from a willow tree.
Taking sediment samples from Crescent pond.
September 2013 –  Taking sediment samples from Crescent pond.
Crescent ghost completed.  The old pond sediment is visible in patches (darkest colour), and will hopefully provide a seed and egg bank from which the pond can re-colonise.
September 2013 –  Crescent ghost completed. The old pond sediment is visible in patches (darkest colour), and will hopefully provide a seed and egg bank from which the pond can re-colonise.
Five weeks on - Crescent pond is filling well, and already contains 6 species of water beetle, a good zooplankton population and a lot of mosquito larvae.  The pond will soon flood into the shallow shelf to the right of the photo, and up to the hedgerow and ditch to the left.  The black 'mini ponds' around the edge of the main pond are part of the experimental set-up, which is covered in another section of the blog.
October 2013 –  (Five weeks on) – Crescent ghost is filling well, and already contains 6 species of water beetle, a good zooplankton population and a lot of mosquito larvae. The pond will soon flood into the shallow shelf to the right of the photo, and up to the hedgerow and ditch to the left. The black ‘mini ponds’ around the edge of the main pond are part of the experimental set-up, which is covered in “components of the ghost ponds project – field, greenhouse and laboratory.”
Week 18 - Crescent ghost is almost full, although it has not quite flooded over the shelf which connects it to the ditch.  As with Original ghost, the water is currently turbid due to heavy rain and sediment run off, but despite this plants are beginning to grow/
January 2014 (week 18) – Crescent ghost is almost full, although it has not quite flooded over the shelf which connects it to the ditch. As with Original ghost, the water is currently turbid due to heavy rain and sediment run off – this will soon clear, allowing plant growth to really kick off.
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February 2014  – Surprisingly, the water level in Crescent ghost seems to have fallen slightly, exposing part of the shallow ledge on the field-side of the pond.  The water in Crescent ghost is much murkier than that in The Swimming pool, which although located in the same field, has a more established buffer strip than Crescent ghost.  Past experience of digging farm ponds has taught us that this murky and turbid phase is common during the pond’s early establishment.  Once plants begin to establish more vigorously in the spring, water quality dramatically improves in most sites.

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March 2014 –  Nick (the landowner), decides to coppice the hedge to the west of Crescent ghost, allowing more light into the pond.  Since this photo was taken, stoneworts (Characeae) have started to appear in the pond, and the previously algal-green water is beginning to clear (although not to the crystal clear quality of the Swimming Pool).  Frog and toad tadpoles are abundant, and smooth newts have been sighted in the hedgerow and ditch running into Crescent ghost.  Surprisingly, a stickleback has been sighted in the pond – whether this was dropped in by a bird, or some how made it in when the river rose (although I don’t think the river made it anywhere near the pond), is a mystery!

crescent-ghost-MayMay 2014 –  Surveying in the rain.  The water in Crescent ghost continues to clear, although the pond remains much greener than the near-by Swimming pool.  Chara germinations are now appearing across the pond.

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May 2014 – A somewhat murky underwater shot of the Chara germinating in Crescent ghost.  These germinations in the pond correspond with those occurring in the microcosms, and in the sealed aquaria in the greenhouse, strongly suggesting that the Chara is returning from the historic seedbank.  This is significant because Crescent ghost was filled in around 150 years ago – so not only have the Chara oospores (seed like propagules), lain dormant all this time, but they have survived some fairly  inhospitable conditions.  Although Chara oospores in lakes have been shown to germinate after centuries of dormancy, this is the first time (I think), an aquatic propagule has been shown to remain dormant for this long in a pond, and in one which was filed in! It seems that despite the dryer conditions, soil compaction and use of fertilisers etc. on the farm above them, these oospores were still able to survive.  This is very promising for the potential of ghost ponds in restoring species to the landscape.

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June 2014 – The water in Crescent ghost is now almost clear, and aquatic plant growth is accelerating.  Underwater, Chara is spreading across much of the sediment surface, while Potamogeton natans (broad leaved pondweed), is beginning to push it’s first leaves to the surface.  The shallow shelf connecting the pond to the hedge is developing a mixture of water-associated vegetation, including hard and soft rushes, as well as Ranunculus sceleratus (celery leaved buttercup).  This area periodically floods with heavy rain, creating a nice transitional habitat.  Many of the tadpoles have now developed into froglets, which are abundant around both Crescent ghost and the near by Swimming pool.  Disappointingly, the stickleback has remained elusive since May, and I am now beginning to doubt it’s existence!

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June 2014 – What a difference a month can make!  In contrast to the sparse stems of Chara seen in May, by June thick mats of the stuff have started to form in the shallow regions of the pond.  A single Potamogeton natans plant has also appeared.

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July 2014 – Due to the recent dry weather the water level in Crescent ghost, as in most of the other ponds, has fallen by several inches.  Otherwise the pond is looking much the same as it did back in June, containing thick beds of Chara (several different species), and now two P.natans plants.

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July 2014 – An underwater shot of some of the Chara growing in Crescent ghost.

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July 2014 – Chara is not only doing extremely well in Crescent ghost itself, but also in the microcosms containing sediment from the pond.  All of the microcosms containing sediment from Crescent ghost, both covered (as above), and uncovered, have had Chara and Potamogeton germinations occurring in them.

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August 2014 – The aquatic plants in Crescent ghost continue to do well, with several P. natans plants having now appeared.  Thick beds of Chara still dominate the pond (and microcosms), and a new species, Potamogeton crispus, has now appeared in the pond.

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August 2014 – P. crispus growing in Crescent ghost (apologies for the poor quality photo!).

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August 2014 – A close-up of the Chara growing in the four covered microcosms containing sediment from Crescent ghost.

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August 2014 –  While aquatic plant germinations seem to have been doing best in the covered microcosms (perhaps due to lack of disturbance), germinations in the open microcosms containing sediment from Crescent ghost are now taking off – above you can see Chara and Potamogeton natans growing in one of these open microcosms.

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September 2014 –  Crescent ghost at one year old.  While aquatic vegetation has been slower to develop in Crescent ghost than in its neighbour The Swimming pool (as you would probably expect considering the seed bank had been buried for over 150 years), the pond is starting to look very nice.  20 species of water-associated plant are now found in and around Crescent ghost, including 4 aquatic species.  Aquatic plants now cover all of the pond, and the water has cleared considerably over the last few months.  Invertebrate surveys revealed both crescent ghost and The Swimming pool to be teeming with life, including a wide diversity of water beetles.

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September 2014 –  A 30-second sweep through the P. natans growing in Crescent ghost unearthed six great diving beetles (Dytiscus marginalis), as well as numerous other beetles and bugs.

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September 2014 –  A great diving beetle (Dytiscus marginalis) – a common, but still impressive, species.

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November 2014 –  Winter rainfall and reduced aquatic vegetation are contributing to the cloudy appearance of Crescent ghost (and indeed the other ponds).  Despite looking rather lifeless from the surface, underwater plants including the stoneworts (chara), and the broadleaved pondweed, are still showing signs of new growth.  There is also plenty of water beetle activity, with great diving beetles and lesser diving beetles regularly surfacing for air.

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June 2015 –  A second spring for Crescent ghost, and the broad leaved and curly leaved pondweed are spreading across the pond.  High water levels during the winter temporarily connected the pond to the near-by river, resulting in a health stickleback population now residing in the pond. It will be interesting to see how this affects the pond’s ecology in the future.

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June 2015 –  A close up of the patch of broadleaved pondweed growing in the centre of Crescent ghost.  Under the water, the abundant stoneworts (Characeae) are visible.

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