It is now about nine months since the ghost and restored ponds were dug, and evidence that the seedbanks of these ponds remain viable, and help re-populate the ponds, is coming in thick and fast.
The first signs that the plants growing in the ponds were indeed coming from their historic seedbanks, came back in November 2013. Fine leaved pondweed germinations were found in the covered microcosms containing sediment from The swimming pool (a restored pond), and Original ghost. These were the exciting first indications that the seedbank of both types of pond remained viable. However, although the microcosms are covered with a very fine mesh (which should stop any seeds from entering by dispersal), it is impossible to seal them off from the environment completely. Although it looked very likely that these early germinations had indeed come from the seedbank, it was still possible that they could be from seeds which somehow found their way under the mesh, or into the microcosms during surveying.
November 2013 – some of the first fine leaved pondweed germinations in the covered microcosms. Unfortunately I didn’t have a waterproof camera at this point, so you will have to look very closely through the reflections, but they are there! This picture is of one of the microcosms containing sediment from the restored Swimming pool, but similar germinations also occurred in sediments from Original ghost.
In the following months, germinations in the microcosms have became more abundant. There are now germinations in at least one covered microcosm for each pond, with species including chara sp, Potamogeton natans, Potamogeton tricoides, Potamogeton crispus and Potamogeton birchtoldii. What was most exciting was when the germinations in the ponds and microcosms were also matched by germinations in the same sediments kept sealed and inside the greenhouse.
The aquaria experiment was set up in March 2014, the sediments from the ponds having been refrigerated until they were needed. Germinations were recorded on the first visit to the aquaria in May 2014, and included as-yet unidentified Potamogeton species, and chara sp.
May 2014 – One of the first germinations occurring in the sealed aquaria, in sediment from Crescent ghost – which was filled in over 150 years ago!
These germinations in the aquaria are truly exciting – they show, under the most controlled conditions possible, that the historic seedbank of both ghost and restored ponds remains viable. In ghost ponds filled in as recently as the 1970s, right through to the Crescent ghost filled in the 1850s, the seedbank is able to regenerate. This has real implications for pond conservation and research; Ghost Ponds have the potential to improve landscape connectivity, biodiversity and genetic diversity through their resurrection.