Gas bubbles

Another trip to Saltfleetby-Theddlethorpe NNR with Chris and Pete, to pick up the pitfall traps they'd set a fortnight ago, as part of their survey of an area of freshwater marsh. I wandered round the nearby dunes while they were working, and heard more Natterjack Toads calling. When we  met up for lunch, they told me that they'd heard huge numbers calling in the shallow pool next to the area where they'd been working, though hadn't managed to see a single one!

The rest of the day was spent visiting areas of saltmarsh within the whole length of the reserve - nearly eight miles, to enable them to prepare a submission for invertebrate monitoring which would be carried out later in the summer. 

This was really interesting exercise - our favourite areas were at the southern end where there is a mosaic of developing saltmarsh and dunes. Some areas of the saltmarsh were covered with these bubbles, which I think is a result of filamentous algae trapping bubbles of oxygen.

This area was also the best for birds, including passage migrants such as wheatear and whinchat (see extra), while the beach had good numbers of shelduck, ringed plover and dunlin, the latter looking very smart in their breeding plumage.

We arrived home later than expected, but luckily Sarah and Ben had made us a delicious meal of vegetable chilli - we'll miss them when they move into their own house!