Go on a circular nature walk taking in Southern Country Park, Thorley Wash and the Stort Navigation
Nature Notes columnist Jono Forgham covers your fortnightly look at nature around Bishop’s Stortford
Having returned from a most successful bird photography trip to The Gambia, where daytime temperatures topped at 42°C most days, I set out last Monday in considerably more clothes in 6ºC. The forecast hinted that it wouldn’t warm up too much, meaning little chance of a wide array of insect species, so I thought I would concentrate upon recently-arrived migrant bird species. Thorley Wash and Southern Country Park would be an ideal area to search, so I parked in the latter’s car park, along Thorley Lane, at 9.30am and set off.
No sooner had I begun my walk when I bumped into Jane, who was walking her labrador. She is a keen reader of Nature Notes, so it was a pleasure talking with her about local breeding buzzards.
I headed off towards the lake. Chiffchaffs called, magpies, jackdaws, carrion crows and rooks all wandered around the short grass, probing for insects, whilst the jackdaws were also collecting nesting material.
At the lake, a pair of black-headed gulls and the resident vociferous mallards. A female mallard posed well for a snap on the boardwalk as I spotted a distant grey heron winging its way over the lake. The light was dismal, so no chance of a sharp in-flight photo.
By the reedbed I heard my first whitethroat of the year. The first of many. I waited for this bird to appear from the willow, but it headed off into a hedge where it was only heard and not seen.
I moved on to the small pond. Blackcaps in good voice here, another whitethroat and my second first-of-the-year species, a skulking garden warbler. These birds are adept at remaining unseen, only being identified by their melodic song. A Cetti’s warbler exploded into its raucous call from deep in a bramble patch. Another warbler that is often heard and rarely seen.
Cowslips were found in profusion in the dog-free area before I took the footbridge over St James’ Way and headed to the churchyard. Little within the cemetery so I checked on the pond here. Two one-day old moorhen chicks were present with both parent birds feeding them constantly. Very confiding birds, I had to walk further away from them to get a full-frame shot.
A chap was also watching these birds and it turned out that he, too, enjoyed my articles. He told me there was a coffee morning in the St Barnabas Centre and invited me in, which I duly did. Lovely cup of coffee in a very friendly atmosphere and I had a good chat about cameras etc before heading back out again.
I took the concrete path from the engineering barns to Thorley Wash Hall. Overhead, a 737 overtook a flock of herring gulls whilst a buzzard circled. I crossed the road and picked up the footpath opposite, only to find the path over the railway line was still blocked off. This has been the case for several months now and it looks like no improvements have yet been made. This habitat held plenty of wren and whitethroats.
Due to this inconvenient closure, I had to walk to Spellbrook Lane East and pick up the tow path at the lock gates. A greenfinch wheezed its rather uninspiring call from a tree near the presently-closed pub and marsh marigolds were in flower in the Stort backwater by the level crossing.
The wetland area at Wallbury was as full of water as I have ever seen - higher than the path - so water was flowing over the path into the navigation. Great tits and blue tits here before I arrived at the footbridge that took me into the reserve. Another Cetti’s here.
Thorley Wash used to hold several cuckoos in late April/early May a decade ago. Last year, I believe, one was present for a while, but I have not recorded this species on the reserve for many years now. I hoped for one today, but none were heard.
The wonderful cuckoo flower was in bloom in the fenced-off area where later in the year the water buffalo will graze. I headed to a favourite patch of vegetation near the wooden footbridge that usually would take me over the railway. Here, I changed to my macro lens, put down my bag and binoculars and went in hunt of insects.
It was still a tad nippy, so not a huge amount on view, but enough to keep me occupied for over an hour. Unfortunately, in colder conditions insects are much more flighty, so many disappeared before I could focus upon them.
A hoverfly, Heliophius pendulus, posed upon a large comfrey leaf and several Pisaura mirabilis spiders, the nursery orb web spider, scuttled off as I approached. Several of these showed a rarer colouration than the normal, with an orange stripe along the back. This is usually white. Eventually I managed a photo of one.
In the nettles, plenty of ladybird species: seven-spot, harlequin and the smaller kidney spot, all of which performed for the camera.
Two fly species caught my eye. Firstly, one with red eyes and orange upon the abdomen, probably Musca domestica, the house fly. Then an all-black species clinging to a nettle. This was a Bibio species and almost certainly Bibio marci, the St Mark’s fly. St Mark’s Day is April 25 and it is around this time that this fly is on the wing. They are the ones with long dangling legs that fly at face height as you walk through well-vegetated habitats, often associating with hawthorn, which is why fishermen, who like them for fly fishing, call them the hawthorn fly.
The final species I encountered and, again in good numbers, was a metallic green weevil. Impossible to be 100% sure on the identification of these very difficult species but I would hazard a guess it was Phyllobius pomaceus, the green nettle weevil. Only microscopic study will absolutely guarantee the precise ID.
I picked up my belongings and walked around the reserve. Reed buntings chipped their monotonous call from willows as I photographed a patch of forget-me-not. I stopped at the water vole bench for lunch and just enjoyed the almost constant calls of the birds.
There are several splendid carvings on the path here, a woodpecker and dragonfly were photographed. Very skillful work, as are the two benches with water vole and otter carvings upon them.
Back at the bridge and north along the tow path. No signs of any damselflies nor butterflies as a very weak and watery sun meant I was casting a very poor shadow. I arrived at the thin bridge over the river before Twyford Locks and crossed. This is known locally as Rolly Croake as once there was just a large oak trunk across the river.
Over the railway line, where a jay was calling from an oak, and up the footpath to the new housing estate adjacent to Whittington Way. I was soon back at the Southern Country Park car park having covered seven miles and certainly seen plenty to write about.
A wonderful wander and completely different to my seven-mile wanderings in the Gambian bush and forests of the previous week. There, I recorded an incredible 237 species of bird and had the most amazing experience. I was far off the beaten track, renting a room in a small beach complex where electricity was intermittent and the water was frequently not running - usually when you most required a shower! The locals were amazingly friendly and on one walk I was invited to join a farmer and his family for a lunch of rice and smoked fish. Delicious.
I include one photo of a Gambian bird here. The more observant may be able to pick it out. I returned home with over 1,300 bird photos which, four days later, I was still editing.
Returning to Thorley Wash, there is a Dawn Chorus Walk planned for Sunday May 12, meeting at 5am. Details can be found by visiting www.hertswildlife.org.uk, clicking on ‘events’ and scrolling down. By then there should be even more birds present, including sedge warblers and, possibly, cuckoo and grasshopper warbler. Should be a lovely start to the day.