Saltholme moth report, 2022
2022 was a busy year for recording moths. The light trap was out more than any other year, a total of 27 times and we also paid a little more attention to non-adults, spending a bit more time in the field searching for larvae, mines and pupae. Such records have been a little neglected at Saltholme in the past, but can be important as they prove breeding which in some ways is of more significance than an adult recorded ‘to light’ and could influence management. Of course, they also provide the opportunity to add species records to the reserve ‘list’.
Highlights this year have included almost 40 new species recorded for the reserve, two firsts for the county, both the most northerly UK records (as far as we can tell), also two locally significant larval finds, The Wormwood (Cucillia absinthii) and Gynnidomorpha alismana, as well as numerous others, including some rather large numbers on our tern and gull breeding islands.
The year started in January with collecting a couple of pupae from under the loose bark that can be found low down on mature Sycamore trees. It was the first time we’d collected pupae and we hoped by putting them in a tub and keeping them safe, adults would emerge later in the year (they did).
January also saw our first caterpillar of the year. We were reducing the height of some hawthorn scrub near to our wet grassland to deter nesting corvids, the brash was used to create habitat piles. Investigation of some of the older habitat piles produced a larva of the beautifully marked, but tiny, day-flying micromoth Esperia sulphurella. The caterpillars feed on dead wood and are a good example of the value of leaving cut scrub in situ when we carry out tasks like this. Of course, numerous other invertebrates also benefit from these piles.
Esperia sulphurella larva
Esperia sulphurella adult
The light trap went on a couple of times in March and a haul of 66 moths on the 22nd was respectable, including the first record for the site of Small Quaker, numbers of which look to have been increasing in the county in the last four years.
April and May saw four new moth species to the reserve. A caterpillar of the Feathered Thorn was found whilst cutting willow. The adult moth flies in Autumn which may be part of the reason it had been unrecorded thus far. We took a couple of photos and re-homed the caterpillar on some willow close by to allow it to continue feeding. The second new record came from finding the feeding signs of Epinotia abbreviana on Wych Elm. The early instar larva eats through a leaf bud, which, when it unfurls reveals a fabulous smiley face type pattern. Later in the year we also had our first adult to light.
Epinotia abbreviana feeding signs on Wych Elm
Next was another day-flyer, Small Yellow Underwing, Panemeria tenebrata, seen in the discovery zone. It’s a pretty little moth. It likes flower rich grassland and its caterpillars feed on the seeds of common mouse ear.
Small Yellow Underwing on Daisy
A very low total of 28 moths were caught in May over two nights. Several caterpillars were seen though, including of Garden Tiger, Ghost Moth and Gold Spot but one of the highlights was certainly the very smart Helcystogramma rufescens spotted and photographed near to Paddy’s pool hide. The species overwinters as a larva and feeds on grasses such as false brome. Adults turn up from mid-June (and are not nearly as smart) - the caterpillars have never been recorded on site before.
Larva of Helcystogramma rufescens
Another excellent find came in early June - a larval web on an apple tree near to the visitor centre. It was the that of the Apple Ermine moth, a smart black and white micromoth that feeds communally on the leaves of apple. The moth is not usually identifiable as an adult without dissection and so to find the webs on site was a great way to prove their presence on the site. Later, cocoons were seen and we also managed to snap a recently emerged adult.
Apple ermine
Another site first record came in the form of a rather fancy ‘longhorn’ moth, ‘Nemophora degeerella’ spotted near to the Phil Stead hide. The males of the longhorn moths have, as their name suggests, very long antennae, with N.degeerella’s being almost four times the length of the wing. It is quite a common moth, being found in woodland and old hedgerows, often favouring damp conditions, but is still a delight to see.
Trapping through June saw the number of species and moths pick up a bit. We got the first hawkmoths of the year with three each of Elephant and Small Elephant Hawkmoth on the 16th and the first Poplar Hawkmoth on the 24th. We also had a record count of The Flame on the 24th, with an impressive 68 coming to light.
Small Elephant Hawkmoth
In June we had our first record of Beautiful Hook-tip for a couple of years. First recorded in 2018 in the county at Saltholme, the moth seems to have been undergoing a northward expansion in range in recent years. We also got records of Obscure Wainscot and Southern Wainscot, both reedbed species that have also been moving northwards recently, and Saltholme, over the last ten or so years has become an important stronghold for them.
In late June, the weekly work party was clearing a path of self-seeded birch and sallow saplings to provide open habitat, with lots of bare ground for species like grayling and dingy skipper, when, quite bizarrely, one of our volunteers found an incredible moth, sat on their bag. The moth in question was the nationally scarce, Six-belted Clearwing, Bembecia ichneumoniformis. It was quite an astonishing find as the species hadn’t been recorded in the county since 1946, and apparently most people consider that record spurious which makes this the most northerly accepted UK record. Added to that, was just how fine a specimen it was, probably recently emerged, the individual was immaculate. We can tell it is a male as it has six stripes, not five as does the female, and, as its scientific name alludes, it is a mimic of wasp species; as its English name suggests, its wings are at least partially clear. A simply marvellous moth.
A belter! Six-belted clearwing on Bird's Foot Trefoil
Pima boisduvaliella, caught in mid-July, was another first for the county, though quite smart, it certainly had a little less wow factor. Until 1999, the species had only been recorded in the south of England, it is found on the coast from Norfolk down to Kent where its foodplant, sea pea grows. It was recorded south of the river, at Teesmouth, in 2011 and 2015 and before that near to Marske in 2006. It is possible that it uses other legumes such as bird’s foot trefoil as a larval foodplant, as sea pea looks to be absent from the Durham and Yorkshire coastlines.
Pima boisduvaliella
Brown-veined Wainscot also came to light in July with two records, and at least two individuals, numbers may be increasing for this reedbed species, it was first recorded in 2020 with a single individual and a single again last year.
Small China-mark and Calamotropha paludella were two more firsts for the site, both with only a single modern record prior to 2022 and both were recorded several times in the season. To light there were six records of 13 individuals of the China-mark and five records of nine individuals of C.paludella.
Two further significant records were of caterpillars of nationally scarce species. In September, two caterpillars of the The Wormwood moth were spotted on Mugwort, near to the Meadow. An adult recorded to light the previous year, had been the first county record, and represented a range expansion northwards, with Saltholme appearing to be, currently at least, the most northerly location where the species has been found, so to find the caterpillars was fantastic as it proved the species has bred on the site. The team had been keen to see these caterpillars, having seen pictures in books, as they are truly amazing and we think they display some of the best camouflage that exists anywhere in the animal kingdom, check out the photo below.
The wormwood caterpillar on Mugwort
Next was the micromoth Gynnidomorpha alismana whose caterpillar inhabits the stems of water plantain, a common plant that can be found in some of our ponds and ditches. The adult has been recorded to light twice, in 2017 and 2020 and it seemed therefore possible that it was breeding on site, so, in November we decided to check inside a couple of the plants. Three stems with small holes in were investigated further and opened up and sure enough one of the stems contained a larva. The larva makes a small hole and uses it to make its way into the stem. Inside, it will eat the pith and will be relatively safe from predation. Once fed, it will spin a cocoon of silk in Autumn and spend the winter there, it will pupate and will not emerge as an adult until the following summer.
Gynnidomorpha alismana larva on a stem of water plantain
Some other site firsts this year included ‘Scallop Shell’, (the 8th county record in the last 100 years), ‘Peach Blossom’, ‘Campion’ and ‘Lychnis’ and some smaller species such as Anania crocealis, (the seventh county record in the last 100 years), Argyresthia goedartella, Eucosma obumbratana and the charismatic Ypsolopha sequella which appears to have an image of a rabbit printed along its back. Vine’s rustic was another interesting species that seems to be spreading northwards, with just six records previously in the county and none at Saltholme, we recorded seven individuals over three dates and it seems possible that it is breeding close by, if not within, the county.
Scallop shell
Ypsolopha sequella
Lastly, it is worth a mention of a large larval find that came as we were clearing vegetation from our breeding cockle shell islands. It’s a job we do every year, once the terns have left. This year we spotted something we don’t usually see. First, there were four caterpillars of the Pale Tussock moth, two of the regular green colour form and two of a darker, black and pink/brown form. Lovely creatures but once we’d got our collective eye in, there were caterpillars everywhere, and of a few different species as well. There were 25 caterpillars of Bright-line Brown Eye, several pug looking caterpillars, which remained unidentified, a Dark Spinach and an astonishing 232 Ruby Tigers. All were placed with suitable food plants away from the islands.
Pale Tussock caterpillar
Lots of rescued Ruby Tiger caterpillars
All in all, 2022 was a great year for moth recording on the reserve and a massive effort from all members of the team contributed to some really great records. In total 290 species were recorded in one form or another, 39 were new for the site and we learned some useful information on breeding status for several species.