Common frog (Rana temporaria) was once very common here but the population crashed around 2010 due to the epidemic of a viral epidemic causing red-leg disease. For some years no frogs were to be found here. Only in 2015 did some frogs start to reappear. By 2017 about half the tadpoles are frog and half toad.
Crayfish have been caught in the pond but there cannot be many of them and we have not yet identified which species they are.
Grass snakes (Natrix natrix) eat mainly frogs and toads which are plentiful here. There are also two piles of harvested grass which will be generating heat as they rot, so are ideal places for the snakes to lay their eggs. Grass snakes also swim well, so the swamp is ideal habitat. But they are elusive and not easy to spot.
Horsehair worm. A parasite with a fascinating life cycle has its own page with some photos.
Moles are common in Pauline's Swamp as evidenced by their many heaps and runs below the soil surface.
Nine-spined stickleback. This fish is less common in Britain than the three-spined, but the sticklebacks in Pauline's Swamp pond are nine-spined (Pungitius pungitius).
Rabbits are not immediately evident, but there are rabbit holes along the western edge and under some of the bramble patches. Rabbits tend to be crepuscular - they come out at dawn and dusk.
Smooth newt.
Toad. Before about 2013 toads were not common in Pauline's Swamp, but when the frogs died off, toads moved into the pond. In 2015 toad spawn was very common and by 2017 both toad and frog tadpoles abound in roughly equal numbers.
Water Vole in 2017 a water vole was spotted by the pond. The water vole is a protected species. The separate page has photos of its impact on the pond, with more details.