Mention has been made on these pages of the efforts made in recent times to improve the reserves value to amphibians and reptiles. Back in the spring a number of the recently dug ‘amphibian pools’ had frog spawn in them for the first time. Although some late frosts didn't help the frogs cause, certain pools hosted tadpoles and over time froglets were seen as miniature facsimiles of their parents.
The pools in question are hydrologically separate from other water bodies making fish colonisation more tricky and fish removal relatively easy. Fish can have a dramatic impact on amphibians as many view tadpoles as an easy and nutritious snack and will often go on snacking until there are no more tadpoles remaining to be snacked upon.
One of the many amphibian pools created over the past two winters.
A couple of weeks ago we had a toad wandering beside a pool, Anne has found newts occupying one of the new pools and in the past week both Nick T and I have seen grass snakes on their ‘grass snake’ piles (logs and vegetation) - a promising sign and possible evidence that these targeted habitat alterations are paying dividends. As grass snakes are primarily hunters of amphibians we would expect to see their numbers increase alongside that of their favoured prey and it appears that this is indeed the case, which is one of the more gratifying elements of this job - from planning to realisation.
The presence of vegetation piles besides water offer manifold grass snake benefits. As well as refugia for the snakes, the decomposing vegetation generates heat to incubate their eggs. Over the next few weeks ‘bootlace’ hatchlings will be emerging and slithering-forth into their wider watery world - so it may be that our otherwise unprepossessing piles of rotting reed are worthy of closer inspection henceforth!
A coiled grass snake.
Possibly the greatest allure of wildlife watching is the tangible sense of anticipation for what may lie around every corner - of possible new species to encounter or new behaviours to witness from more familiar characters. The scene below was photographed by regular (almost resident) visitor Dan Dench and probably falls into the latter category as, to my knowledge, a fox taking to birdwatching is an entirely new phenomenon.
Strangely the moorhen seems either unaware or unconcerned by the cunning ones intense predatory gaze - or perhaps a summer spent avoiding the clutches of our marsh harriers have provided a sense of perspective, enabling it to view a mere fox with a world weary shrug of the shoulders?
Many thanks to Dan for the photograph.
We have recently received a couple of enquiries about the why's and wherefores of cattle on the reserves as it can appear incongruous to have hulking great bovines trampling and munching their way through our precious reserves.
The cows on Radipole and Lodmoor through spring, summer and autumn maintain a low diverse and varied sward to the benefit of a wide array of wildlife, from invertebrates to birds and mammals. If unmanaged the grassland will become ‘rank’ which essentially means a few vigorous plants dominate, benefitting relatively few invertebrates and the shorter sward required for ground nesting birds and wintering waders and wildfowl is not provided.
Our fantastic residential volunteer Irene - at one with the herd. She is Spanish and it is fiesta season which may possibly explain why they are cowering beneath the willows!
Mechanical control with tractor mounted equipment can maintain a low sward height but does not promote the tussocks, (micro scale hillocks which act as invertebrate refuges) which cattle produce by preferentially grazing more palatable vegetation types and by poaching the soil with their hooves – which also adds areas of bare soil for certain insects to exploit. Mechanical cutting is more intrusive and made difficult by the ground conditions across much of the site. That said we do mechanically manage hard rush as it is too coarse for even our hardy herd and this is undertaken outside of the nesting season.
Cattle are also charged with the responsibility of grazing pool margins thus maintaining open water where otherwise marginal vegetation would encroach, ensuring feeding opportunities for sight feeding fishers such herons, kingfisher, egrets and bittern. Obviously there exists the possibility of ground nests being trampled but the benefits far outweigh the cons as there would be far fewer nests were it not for the cattle maintaining a rich and varied sward.
Our cattle are owned by Peter Broatch of Eweleaze Farm ( http://www.eweleaze.co.uk/ ) in Osmington and are organic Aberdeen Angus - a famously hardy breed, well able to cope with the rigours of wetland life and not too fussy about the vegetation upon which they are forced to dine.