Top Llan - late post

I photographed this wasp up Top Llan a few days ago, I initially thought it might be a common wasp but didn't look quite right so I put it on Irecord. It turns out that my doubts were well founded as it turns out to be a Norwegian Wasp. Paul Tabor has already had a few records down the lower end of the valley but its new for me. [Even later post - I was back up there on the 31 July, so I did a count of wasps feeding on Hogweed knowing now what I'm looking for and came out as thus - 114 Tree Wasp, 28 Norwegian Wasp, 6 Common Wasp.]

Top Llan other stuff

The rain has benefitted other insects beside hoverflies. I recorded 13 species of butterfly including Painted Lady. Bees and Wasps were everywhere and I came across a monster queen Buff-tailed Bumblebee, the biggest I have ever seen it was close to 2" in length. Lots of Plant bugs present too lead by Deraeocoris Ruber. Harlequin Ladybirds have started to arrive also. Tachina grossa (UK's largest fly) out in good numbers as was other tachinid flies. I also came across an orange fly I'm not sure of, so I've put it on Ispot for confirmation if possible. Moths were represented again by numerous Pammene aurana, Grapholita compositella, Silver Y and 6-spot Burnet. I also have 12 new flower blooms for the year.

 Buff-tailed Bumblebee - monster queen

 Harlequin Ladybird - tucked in Hogweed seeds

 Small Copper and Ringlet on Ragwort

 awaiting ID on this one. Will update when confirmed [ID'd on Ispot as "Phaonia subventa" (a muscid fly)- new for valley]

6-spot Burnet

low numbers of hoverflies due to heat - like F**k

Ha!. The moment I moan about low numbers of hoverflies due to the heat. I visit Top Llan (Gilfach (west) and the place is dripping with them, 1/2 dozen on each flowering hogweed plant and there are 200+ plants in bloom. I recorded 35 species with 1000+ flies present. The three species I wrote about in the last blog were all present in high numbers. Episyrphus balteatus a passage migrant largely absent until now was streaming in from a southerly direction and moving along the lanes. Conservative estimate 75 flies. Eristalis pertinax numbered 40 and Syritta pipiens numbered 260 but that was to be expected. Other species seen that were either first for the year or have been scarce this summer were Melanostoma mellinum, Melanostoma scalare, Platycheirus albimanus, Eupeodes latifasciatus, Syrphus ribesii (30+), 6 species of Cheilosia, Eristalis rupium (female), Eristalis tenax, Sericomyia silentis, Volucella pellucens, Platycheirus granditarsus and Helophilus trivittatus. Why so many, well the mist and light rain has brought out the surviving damp/water species and the rain has also seen an explosion of aphids for the species that feed on them at the larva stage so adults were frantically laying eggs.

 aphids on Hogweed were numerous to say the least

 Helophilus trivittatus

 Sphaerophoria scripta

 Eristalis tenax

Platycheirus granditarsus

Heat affecting hoverfly numbers

As I write this, the valley is full of mist and light rain, so seems a bit unusual to make heatwave conclusions right now. But 2018 has been a poor year for hoverflies so far this season and that is due to the unusual heatwave affecting the country. 2017 was typical of the years we have been having lately with wet mild winters and equally wet summers with short intervals of dry warm weather. These conditions worked favourably for hoverflies, allowing the different types of larva feeding to maximize their numbers. 2018 however has reverted back to the weather we used to experience "when we were young", that is extremely cold winters with quite a bit of snow cover. In fact January to May all came in much colder than the average temperatures. June and July on the other hand have been very hot and dry, with drought fears being reported by the national press. Temperatures regularly over 25c have been disastrous for hoverfly larva. The aphid feeders are finding it hard to find food as aphids are the first things to disappear during a drought, The rot-hole larva are just plain dying as all water sources are drying out. This year I have witnessed Myathropa Florea feeding on sap runs and Eristalis nemorum, Xylota segnis and Syrphus torvus all obtaining fluid from exposed mud that is drying out where there should be ponds and streams. Not all hoverflies are affected with Syritta pipiens numbers going through the roof. Below are three graphs of common species, with different larva feeding preferences and how the numbers have been affected so far this year.

Episyrphus balteatus (aphid feeding larva) - is a common European migrant, numbers start arriving in April but pick up greatly in June to August, where the adult lay eggs near large congregations of plant Aphids, then some make it back south, while others try to overwinter. The cold weather from January to May killed off the entire spring brood from the previous summer, so none were recorded until early June. The adults now arriving find that their aphid food source is greatly diminished, so there is no continuation of the life cycle and adult numbers are not inflated by last years brood with numbers crashing. As a migrant this species needs the hot weather to break and the winter to revert back to wet and mild for numbers to recover quickly.

Eristalis pertinax (aquatic type larva) - the larva of this species occur in a wide variety of wet areas, including, streams, silage, manure, wet bogs, damp decaying vegetable matter. The spring brood [from last autumn] hasn't been affected much because the wet habitat had not been overly affected by the cold weather. In fact numbers are higher than normal and looked to have done well in the early part of the year. But as soon as the heatwave kicked in in June numbers plummeted as the larva are dying off in large numbers in the wet places that have dried out quickly because of the drought. In July it should be one of the most numerous of species about, from the graph you can see numbers have plummeted 60%, which is also the number drop for the overall count of the 130 species so far recorded in the valley. Again the weather has to break to see an improvement, as it is multi-brooded this species should be able to recover faster than some other species.

Syritta pipens (aquatic type larva) - this species has seen a dramatic increase in numbers since the drought started and there has to be a reason why. The larva are found in wet decaying organic matter like compost heaps, manure heaps, cow-dung and silage but not in pools or ponds. The reason maybe that as the pools and ponds dry up the silage, compost and manure heaps retain their moisture through the fermentation process within these heaps and are not affected as such by the hot dry weather except to crust on the outside of the heaps, thus the numbers have been less affected. When the larva become adults and fly to feed and breed, their predator numbers are way down and has allowed their numbers to flourish [nature out of balance]. A word of note though, this week I have seen local farmers gathering up their compost and manure heaps and spreading them over their fields to increase grass growth for their cattle and there are few heaps now left. So this species may not be out of the woods yet and a knock-on effect may occur next year unless the weather cools.

Blaencaerau coal reclamation site

20 species of hoverfly were seen today, but it was definitely an Eristalis day, with all seven of the valleys species being seen. The five common species were in good numbers - arbustorum (20), horticola (12), nemorum (35), pertinax (80) and tenax (8). The two rarer species were also seen and posed well for photographs - intricarius (male), rupium (3). Also seen today was first for the year in Helophilus trivittatus.

The only dragonfly seen today was a male Keeled Skimmer. Tree Bumblebees were the best of 6 species of bees seen. Other insects were the norm except for Tachinid flies, where I recorded Tachina grossa, Tachina fera and Eriothrix rufomaculata. 9 species of butterflies were headed by 13 Ringlet, there was also 4 Silver Y migrant moths.

Both pairs of breeding Stonechat have 3 well grown juveniles. The Swifts have taken flight today with 22 juveniles which equates to 8 pairs, the lower end of the normal counts [8-15 pairs]. The adults kept away from the screaming juvenile pack, they'll all be gone for another year in a day or two, but I think there are at least other 3 pairs acting as if their juvs have not fledged yet. [25th July update - another 10 Juvs have fledged, meaning 32 juvs from 12 pairs which is a slightly better than average year].Three House Martin nests have been located and active [+1 from last year], but no flying juvs yet.

 Eristalis intricarius (male)

 Eristalis rupium

 Tachina grossa

Eriothrix rufimaculata

Garnwen

30 species of hoverfly were recorded at Garnwen today with the highlight being 3 Eupeodes lapponicus. This is the 3rd year on the trot that I have recorded this species in the valley here, they are the only records for Wales and looks like this species has a stable colony here. Common Fleabane seems to be the favoured food plant for adult flies. Other highlights included Sphaerophoria philanthus and Eristalis rupium.

An impressive 13 species of butterfly were recorded including Painted Lady, Red Admiral, Brimstone and high numbers of Gatekeeper. Bees had all the usual species with Patchwork and Willoughby's Leaf-cutter bees present. The first Stictoleptura rubra longhorn beetle female of the year was present amongst the males. Tree Wasps are now very numerous as was the Tachinid flies Tachina grossa and Sicus ferrugineous..

 Painted Lady

 Peacock

 Brimstone

 Stictoleptura rubra - female with red thorax

 Stictoleptura rubra - male, much paler with black thorax

Dasysyrphus albostriatus

 Eristalis nemorum - with the male above the female in characteristic hovering flight seen only in this species.

Cheilosia impressa - small black species with yellow base to the wings.

Iceland (part 4/final part) - hoverflies and other stuff

Iceland only has a short list of 21 species of hoverfly, recorded mainly from visiting dipterists. I photographed a number of species around the Island and had the ones I was not familiar with kindly identified by Gerard Pennards of the world database for hoverflies [Syrphidae.com]. Two of the species were new for Iceland and they were Eupeodes rufipunctatus and Platycheirus manicatus. So I managed to get my name into the annuls of Iceland hoverfly recording. Other species seen which have been recorded before and are also common in Great Britain were - Sphaerophoria scripta, Dasysyrphus pinastri, Dasysyrphus tricinctus, Platycheirus albimanus, Neoascia tenur and Syrphus species (ribesii/torvus). The only other animals seen were two separate sightings of Arctic Fox, Iceland's only mammal.

Eupeodes rufipunctatus - new for Iceland (Lake Myvatn)

 Platycheirus manicatus - new for Iceland (Lake Myvatn)

Arctic Fox - (Latrabjarg, Westfjords)

Gilfach (west), Maesteg [Top Llan]

It's not since 2nd June (35) have I had 30+ species of hoverfly (31) in a day. So today's numbers around the lanes next to the forestry was indeed welcome. New for the year or not seen for a while were Didea fasciata, Dasysyrphus albostriatus, Epistrophe grossulariae, Leucozona glaucia and Lejogaster metallina.

Ten species of butterfly were headed by Comma, Small Copper and ever increasing numbers of Ringlet (60). The Longhorn beetle Leptura maculata was recorded, and a Sulphur Beetle was on Hogweed. I've checked my records and I think it is new for the valley, I've only ever seen them down at the coast at Kenfig NR, inland records are very few and far between. Silver Y and Pammene aurana moths were feeding on Hogweed as were large numbers of Orange-legged Furrow Bee, Tree Bumblebee and a few Field Cuckoobee. New blooms for the year were Upright Hedge Parsley and Lesser Burdock.

 Epistrophe grossulariae

 Dasysyrphus albostriatus

 Leucozona glaucia

 Chrysogaster - I've taken this fly as a specimen and it keys out to Chrysogaster cremiteriorum which would be new for the valley. So will have to wait for the answer at the end of the year when I send the specimens to the Hoverfly Recording Scheme for identification. Although from the picture you can see the wings are clear and have yellow base to them and the sides of the thorax are dusted grey, this separates them from the other two Chrysogaster.

 Sulphur Beetle - new for the valley and usually coastal in Glamorgan

 Comma

Tir-iarll Park, Cwmfelin

With temperatures dropping to 20c and a fair amount of cloud cover, the direct heat of our two week sunny spell has dissipated. This meant that hoverflies are starting to show themselves again. I recorded 18 species today, the highlights being the first of the year of Leucozona laternaria and Cheilosia vernalis as well as good numbers of Cheilosia illustrata, Chrysogaster solstitialis and Syritta pipiens. The Hogweed is now in full bloom, so if temperatures stay the same hoverfly numbers should increase greatly.

Red Admiral and 2 Small tortoiseshell were the pick of the 6 species of butterfly seen, the first of these for quite some time. Pammene aurana, Carcina quercana micro moths were the first for the year as was the Green Froghopper, both on Hogweed. The micro moth "Horse Chestnut Leaf-miner" was also present and now seems to be affecting every tree in the valley.

 Cheilosia illustrata

 Cheilosia vernalis - once you realise that this small Cheilosia is not a Chrysogaster, it is easy to pick out amongst other species.

 Leucozona laternaria

 Myathropa florea

 Syrphus ribesii - the female ribesii is the only Syrphus that can be safely identified with confidence from a photograph, due to its all yellow/orange hind femur. All others have to be checked in hand under 20x magnification.

 Carcina quercana

mine of the Horse Chestnut Leaf-miner. Now infesting all the trees in the valley.

Dragonfly ponds, My. Bach

A few years ago the company that was landscaping the old Coegnant colliery area put in some Dragonfly ponds half way up My. Bach. As the weather is too hot for anything but dragonflies and butterflies, I thought I'd take a stroll up there today. There are three small pools and the dragonflies have taken well to them. Just up from the ponds is a small mountain stream that also held a number of dragonflies. They are set at 242mts above sea level.

 Pool 1 [most southerly] - held 1 Emperor, 3 Keeled Skimmer, 1 Southern Hawker, 4 Common Blue Damselfly.

 Pool 2 [middle one] - held 1 Emperor, 3 Keeled Skimmer, 2 Southern Hawker, 2 Common Blue Damselfly.

 Pool 3 [most northerly] - held 1 Emperor, 5 Keeled Skimmer, Southern Hawker, 2 Scarce Blue-tailed Damselfly, 2 Common Blue Damselfly.

 Small mountain stream [just above ponds] - held 1 Emperor, 6 Keeled Skimmer, 2 Common Hawker, 2 Southern Hawker, 10 Common Blue Damselfly, 3 Large Red Damselfly.

female Emperor egg depositing in the mountain stream.


Also of note were the large amount of butterflies in the area, the best being 2 Dark Green Fritillary around the stream as well as two more on the side of "Tyson's Road" on the way up. The latter site was a well known area for Dark Green Fritillary before landscaping with 20+ individuals present. It was thought the site was lost, but they now seem to be making a comeback. Other butterflies in the area included 4 Green-veined White, 4 Small White, 5 Large White, 50 Small Skipper, 20 Large Skipper, 1 Common Blue, 4 Speckled Wood, 1 Gatekeeper, 60 Meadow Brown, 20 Ringlet and 1 Small Heath.

Most of the ponds also had a healthy population of Common Frog, but didn't record any newt species  though. New blooms for the year included Marsh Woundwort, Eyebright, Himalayan Balsam, Agrimony, Charlock, Meadowsweet, Greater Plantain and Green Figwort.