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Situated on the north side of the A127 road not far from Basildon, the Noak Bridge Nature Reserve consists of about 20 acres of mixed grassland, scrub and developing woodland, with several ponds of various sizes adding to the wildlife interest. There are a number of distinct habitat types within the confines of the reserve, with the more open grassy rides contrasting with scrubby thickets and secondary woodland. To assist with the landscaping a selection of trees were planted along the embankment on the south side of the reserve and these are generally maturing very well and add extra variety to the fauna and flora present on the site. All of this has the potential to yield a good diversity of invertebrate species, not least of all the moths. The time therefore had arrived to make a start on unravelling the secrets of the nocturnal Lepidoptera of this particular natural haven. First Steps My initial foray to the Noak Bridge Nature Reserve to perform some moth recording was on the evening of the 29th June 2009, a warm and mostly overcast night that proved very productive for the number of moths obtained. Assisting me with my project were Betty Haynes, Chair of the Noak Bridge Nature Reserve Society, and Les Steward who often uses a moth trap for recording on Vange Marshes. In total we had three 125 watt mercury vapour (mv) bulbs, one on a tripod and the others each on a trap, namely the Robinson and Skinner versions which are the most popular types of moth trap currently in use as they retain most of the insects that enter the trap. Around the tripod lamp and each of the traps I placed a quantity of old egg trays to provide an additional place of refuge so that the moths could be examined at leisure, with the tripod lamp belonging to Les serving as a focal point for our evening sojourn. All of the lamps and traps were each sited over a white sheet so we could maximise the number of individual moths seen - many would otherwise be lost in the grass and undergrowth in the immediate vicinity of the traps. It was already dark by the time we started recording, first setting up the tripod lamp once the generator was started and primed for action. Once the bulb had reached its full brightness, I unravelled more cable and set up the two traps along the main east-west ride to either side of the central tripod lamp, thereby making sure that plenty of distance was obtained between all three light sources and thus helping to attract a greater number of insects. With the abundant bramble present it came as no surprise to discover numerous Buff Arches arriving at the lights, with more than two dozen noted altogether. Other species almost equalling this total were the Clouded Silver, Common Emerald, Smoky Wainscot and the Flame. These are all generally common moths, but as with so much of our wildlife in this modern age we have conclusive proof that most species of moth are declining in numbers, some quite alarmingly so in south-east England especially where human pressures leave little room for natural havens. Probably the prettiest insects that night were the Barred Yellows which have larvae that feed on dog-rose, and also the Green Carpets, these creatures being most beautiful when newly-emerged as on this occasion - their larvae feed on various bedstraw species. Another bramble feeder is the unmistakeable Peach Blossom, this moth turning up in small numbers in most wooded habitats in our corner of Essex. Other agreeable species noted were the Swallowtail moth, July Highflyer and the Blood-vein, the last named having a distinctive reddish line across its wings, hence the early entomologists naming of this creature. More localised moths putting in an appearance were the Dotted Fan-foot, Slender Brindle and Southern Wainscot, but even more unusual were two Brown Scallops, these having larvae that utilise buckthorn (Rhamnus spp.) as their pabulum and formerly were known only from the north-west of Essex. However, in recent years they seem to be increasing their range partly, I suspect, because of the planting of buckthorns in some parks and Nature Reserves. This certainly appears to be the case where I live in Rayleigh where the moth occurs in my garden not infrequently during late June. Very close to me is the Woodland Trust property of Wheatley Wood where buckthorns have been extensively planted, possibly bringing the ova and larvae with them from sites outside our own area. The moth itself is very plain and nondescript and could easily escape attention. It therefore appears that one or two species may be benefiting in the early 21st century and bucking the trend of moth species diminishing, or even disappearing completely. Hopefully this will continue to be the case! The evening also yielded a couple of Blacknecks, another scarce Essex moth, the larvae of which feed on tufted vetch, a plant that appears to thrive in the open grassland areas at Noak Bridge. Several of the dainty and diminutive plume moths Platyptilia pallidactyla (no English name) were present at one of the traps, no doubt due to the abundance of yarrow plants on which the moths lay their eggs. In total, we accrued a total of 67 species of the larger or macro moths, with a modest assortment of the generally smaller micros also identified - these are a specialised field in themselves and one which I'm still learning about, albeit rather slowly! Eager Return My follow-up visit was a month later on 31st July, once again mostly cloudy and satisfactory conditions for moth recording. On this occasion we noted 61 types of macro moth, with one in particular making this evening very noteworthy as it confirmed the presence of a breeding colony of a moth thought only to be an infrequent migrant to the south of Essex. The insect in question is the Tree-lichen Beauty, a small and well-camouflaged creature that flies in mid-summer and appears more prevalent in and around damp woodland. One of the traps had been placed along Plotlands Way, the main access track into the reserve from Eastfield Road and very near Willow Pond, the main body of water within the site. Along the path are some mature willow and sallow trees, many with fine accumulations of lichens growing on the bark - this is vital clue to the occurrence of the species on the reserve as the larvae feed only on lichens. It seems the luxuriant growth of these on many of the trees, notably the Salix species, has seen the moth settling down here and hopefully sustaining a healthy colony for many years to come. The Tree-lichen Beauty may have been breeding here for some years, perhaps established by a single female moth that found an ideal location to lay her eggs. It may only be a humble moth that hardly anyone has seen, but at least it proves that some insects are able to take advantage of favourable local conditions and start afresh in completely new surroundings - even if it means they have to navigate across northern France and the English Channel to get here! The first of the Tree-lichen Beauties was seen at about 22.30 at the Plotlands Way trap - the moth had settled unnoticed on the white ground sheet in front of Betty and myself. At first I could not be positive if this was indeed this rare moth as it was rather worn and not in pristine condition. However, I need not have worried as a trip to the next trap supplied me with a couple more of the moths sitting on the sheet, these being easily identified as they were in virtually mint condition and very pretty. I eagerly walked down to the third trap and, sure enough, another one was waiting to be found next to the trap! During the course of an hour or so I recorded six Tree-lichen Beauties, and I had only ever seen two of these insects in all my previous years of moth recording! The strange thing is that none of these were actually in any of the traps - they had all preferred to alight on the sheet and then just sit tight. I have also perceived this to happen when I found another undiscovered colony of this moth at Cranham Marsh Reserve near Upminster on the 10th August where a similar number were recorded. I'm hopeful that the hibernating larvae of this insect have survived the unrelenting cold and snow of this past winter as they generally experience similar weather in mainland Europe which - until the past few years - was their usual home. All being well, I intend to continue my studies concerning the Tree-lichen Beauty in 2010, and possibly unearth some more colonies of this intriguing insect. Although the 'exotic' new arrival was definitely the highlight of the evening, we had several other interesting species to divert our attention. The handsome and appropriately named Chocolate Tip was one of the first moths of the night to be recorded, but shortly afterwards I could add the likes of Broad-bordered Yellow Underwing, Clouded Border, Drinker moth, Pale Prominent, Purple Bar and Ruby Tiger to the list. These are not uncommon moths in our area, but of more eminence were the Webb's Wainscot, Olive and the Red Underwing, the last mentioned being a particular beauty and also very inquisitive as it settled several times thus allowing wonderful views of its red and black hind wings. One other moth of special note was the Dark Umber, a dark brown and rather plain-looking insect which, like the Brown Scallop seen on my previous session, has larvae that feed on buckthorn shrubs, and it is likely they have also materialised in our part of Essex due to transportation of the plants. August Trips My friend Don Down and I made two more journeys to Noak Bridge in August to see if any other species could be added to the moth fauna of the reserve. On our visit of 8th August we specifically wanted to record the Tree-lichen Beauty again, but we noted only a single individual of this particular rarity - but at least this was a perfect and very brightly marked insect, probably freshly hatched from its pupa that day. We managed a modest total of 51 macro species, including Common Wave, Coxcomb Prominent, Dark Spinach, Magpie moth, Poplar Grey and several Sallow Kittens, the larvae of the last named feeding on the foliage of the plentiful sallow and willow trees. We had a few species that arrive regularly to our shores as migrants, these being the Silver Y, Dark Sword Grass and the tiny but distinctive Diamond-back moth. The ponds provide a habitat for a family of micro moth species whose larvae spend their lives underwater and feed on pond vegetation - the three types known as the Brown, Small and Ringed China Mark moths were all on the wing on this evening. A couple of more unusual insects visiting the lamps were the Small Rufous and two Barred Rivulets, the last mentioned being quite localised in Essex and is generally found in dry grasslands where the larval food plant of red bartsia grows profusely. We managed one final trip to the reserve on 19th August and once again we used three bulbs - one on a tripod and two strategically situated traps as in the previous sessions. We stayed for about two and a half hours after beginning proceedings at 22.00 - the moths were rather sparser than we had experienced before, with a haul of 46 macro species attracted to the lamps. Some of the more numerous were the Brimstone moth, Cloaked minor, Common Carpet, Copper Underwing, Flounced Rustic, Lesser Broad-bordered Yellow Underwing, Light emerald, Willow Beauty and the bizarrely named Setaceous Hebrew Character, all normally common moths in similar habitats across much of central and southern England. Other attractive moths gracing the evening were the Maiden's Blush, Small Blood-vein and a Swallow Prominent, along with the tiny and easily overlooked Chinese Character, a fascinating creature that avoids predators by mimicking a bird dropping! Some more worthy finds included the Old Lady moth, a large but sombre creature that fluttered bat-like around the tripod lamp several times before heading off into the night. Two of the migrant moths known as the White-point were seen, but no other overseas visitors could be jotted down on this particular evening. In my experience, the Six-striped Rustic generally only appears as an occasional guest at the lamp, but here we had a total of at least five insects so the habitat is obviously very accommodating for it! Probably the most colourful moth of the night was the Orange Sallow, its bright wings standing out easily amongst its rather more drab and abundant cousins. Unfortunately I could not return for another visit in October due to holiday commitments, but no doubt many of the usual autumn species would be present on the reserve, particularly as there is plenty of sallow hereabouts. Many of the captivating and strikingly-coloured moths of this time of year have larvae that utilise Salix species at some stage of their life cycle, some just feeding on the catkins until they fall to the ground and then gorging themselves on the likes of dandelion and knotgrass. Although the reserve is quite small, it packs a lot into the confines of its boundaries. Much of the wildlife is well documented, but the moth population is now starting to reveal itself and hopefully the list of species recorded will continue to increase with further visits intended for the coming year. Anyone who would like to join me on site to discover more about these 'beauties of the night' are most welcome to come along. I have no definite dates fixed as yet as it generally depends on favourable weather conditions - and everyone has a hard time trying to predict them accurately, whatever the time of year! - Graham Bailey montanabillgs@hotmail.com (first published in a 2009 newsletter of the Basildon Natural History Society) see also The Lure of the Clearwing by Graham bailey |