Urban bush-crickets: the Short-winged Conehead

 

The Short-winged conehead looks very similar to its Long-winged relative. There are green and brown forms, both with a darker dorsal band. I find that short-winged coneheads tend to have darker, pinkish eyes and a reddish tinge on the brown parts. The main differences with the Long-winged Conehead are the short wings, not reaching the tip of the abdomen in (most) adults, the slightly curved ovipositor of females and differences in the male cerci that are hard or impossible to see in the field. The male songs  and the habitat also differ. 

Nymphs appear in June and can sometimes bask in good numbers.

In July, Short-winged Conehead nymphs can be found at the same time than adults.

Behaviour. Short-winged Coneheads are active during the day, basking at the top of clubrushes or grasses, sometimes on seedheads. They are very well camouflaged in natural vegetation. Males call from perches at peak frequencies about 25 KHz. It is common to find many individuals on a small area, although they tend to keep their distance from each other.

A patch of saltmarsh holding a Short-winged Conehead population at the mouth of the river Hull

Habitat. Marshy areas near coasts, estuaries, wetlands and rivers, on rushes or marram grass or reeds. Many northern populations are coastal.

Fieldcraft.  Male song is not audible to all people, so a bat detector is useful. Binoculars come in handy to scan vegetation from floodbanks near saltmarshes. Remember to check any posts or fences, which make convenient basking spots where the bush-crickets stand up. Nymphs can also be found on flowers.

A female  brown form of the Short-winged Conehead basks on the seedheads of Sea Clubrish, where she's perfectly camouflaged, similar shape and colour as the seedheads. 

A female Short-winged Conehead of the typical colour morph.

A male basking and calling from a patch of Sea Couch.

Male Short-winged conehead on a patch of brambles near saltmarsh.

Rafting eggs? Although there is a rare form of the Short-winged Conehead (below) which could be responsible for long-distance dispersal and colonisation of new sites, the species appears to disperse along the coast, estuaries and other waterbodies. Experiments have shown that the eggs can survive salt water inmersion for up to 3 months, which is not surprising, given that most of the vegetation where they perch in the summer is submerged as the rush stems collapse in the winter and are under the high tide line for much of the time. Winter storms often dislodge clumps of marginal vegetation (which might contain eggs) and if these rafts land high up on the tideline the eggs could hatch the next spring on suitable habitat.

A very poor shot of a long-winged form of the Short-winged Conehead. 

A vegetation raft moving along the river Hull with the tide.

Urban bush-crickets: the Speckled bush-cricket

I photographed my first Speckled Bush-cricket over 10 years ago, but it was an accidental photo of a nymph on a leaf with the insect I was actually focusing on, and I didn't actually see it at the time. Fast forward to September 2022, when I was intent on ticking this enigmatic bush-cricket from my urban insect list. I visited a brownfield site in the city outskirts where a population had been recorded, armed with a bat detector, and I quickly tuned to Speckled Bush-cricket station: 40 KHz, a similar frequency than Pipistrelle bats, the actual call a sharp 'tak' reminiscent of two stones hitting each other, repeated every few seconds. When there are more than one individual you can hear how they respond to each other, with closer, louder 'taks' followed by more distant 'taks'. In fact, in this species males and females stridulate and their calls aid them to move closer together. Now, much as hearing the calls was exciting, my challenge was to actually spot the callers, and this took a lot of patience and triangulation, but I did manage to spot and photograph this calling male.

Male Speckled Bush-cricket, Makro site, September 2022.

An early instar Speckled bush-cricket nymph, Sculcoates, 25th May 2024

Speckled bush-cricket nymphs can be seen from May onwards, they are tiny, but stunning and worth searching for: oversized antennae and head, all green with black specks all over their body, and black-stripes on their legs and antennae. Adults can be found from July to October. They are apterous, the only remaining parts of the wings are those making up the stridulatory apparatus. Males are smaller and more elongated than females, green with a brown dorsal stripe, females are all green and are stocky, with a humped appearance. The lay eggs in the bark or crevices of trees and bushes, near the ground.

Female Speckled Bush-cricket. Note the broad, up-curved ovipositor.

Behaviour. I likened Roesel's to a small toad scrambling on the grass, insetead Speckled Bush-crickets remind me of chameleons: perfectly camouflaged, perched on vegetation, still, and when they move, they do it in slow motion and in a deliberate way. 

A population of Speckled Bush-crickets thrives on neglected gardens and hedges. Brambles are a favourite plant, but they climb high on trees too.

Habitat. Speckled bush-crickets are found in a wide variety of habitats, which the common species across them being brambles: woodland edges, overgrown hedgerows or gardens, parks and brownfield sites.

Fieldcraft. Nymphs can be searched for near the ground, on nettles and bramble and other plants. An insect net can be effective on grass near brambles and nettles, but careful inspection of known sites are likely to be rewarding. Adults are much harder to find and a bat detector might help. Scan each bramble leaf, and good luck! I find this the hardest species to find and many of my records are sound recordings of the bat detector, having stared at bramble leaves for a long time. It doesn't help that adults can climb tall trees and shrubs and be found up to 14 m above ground. Using the bat detector I have unexpectedly found new colonies across the city, and it is always exciting to return the following year in spring to find the new nymphs.

There are three species of urban bush-crickets in this patch of brambles: the hardest to find is the Speckled Bush-cricket.

A male Speckled Bush cricket found with the aid of a bat detector on the edge of a local park. Note how their colour mirrors the leaf damage on brambles. Despite usually sitting on the top of leaves, they are very hard to spot.

Stowaways. Despite its flightlessness, the Speckled Bush-cricket has managed to spread from its European native range to islands like the isle of Man, Ireland and even across the Atlantic, with several populations near harbours of the US and Canada, where it most likely arrived as eggs in imported ornamental trees or bushes.

Urban bush-crickets: Long-winged Coneheads

The Long-winged Conehead, together with the Roesel's featuring in the previous post, are the two most common bush-crickets in the UK now, and the most commonly found in urban settings. This wasn't always so, in fact, Long-winged Coneheads are relatively recent arrivals, with the first records in the south English coast in the early 1940s. Aided by those long wings and full flying abilitties, their unfussy habitat requirements, and climate warming, the species moved north swiftly, and currently the northernmost records reach North Yorkshire.

A female nymph. The straight ovipositor makes identification of females nymphs possible.

This is a long, thin bush-cricket, about 15 mm long. Nymphs are usually bright green with a dark back, and adults are more variable in colouration as the top shot illustrates, whilst keeping a darker dorsal stripe lined with yellow. Your eyes will be quickly drawn to the straw-coloured female and her long, straight ovipositor, but look again and you will see the green courting male behind her!

Behaviour. Long-winged Coneheads are in their element on long rough grass, where they are beautifully camouflaged. They are very alert and agile insects, and quickly hide behind a blade of grass if disturbed, or jump onto vegetation and dive down.

A female Long-winged Conehead in typical pose, ovipositor alongside a blade of grass.

After I got too close, she deftly hides behind the grass, only her legs claspling the blade visible.

Males tend to perch high on blades of a tussock of grass and stridulate to attract females. They call mainly during the day in sunny, warm weather, but also in cool weather provided it's sunny. In cool, autumn days, they like to bask on vegetation, often making themselves more exposed on logs or leaves, and lean to expose the side of their body to the sun, with a lowered, extended hindleg. Females lay eggs inside plant stems and most adults will be gone by late October, early November. The next generation will emerge in May or June. Long-winged Coneheads are not particularly social, but it is not uncommon to spot some individuals basking almost next to each other.

Basking female (above) and male Long-winged Coneheads.

Field craft. Whilst slowly walking across grass, watch ahead for movement, and try to spot landing sites. If you carefully crouch nearby, coneheads will soon move onto higher perches and expose themselves. You can also scan suitable basking sites with or without binoculars. Approach slowly and carefully to avoid disturbance. Stridulation is a continuous reel, inaudible for most people as it peaks about 26 KHz. A bat detector is very useful, their call sounding like a helicopter or generator. The presence of stridulating males is a good way to detect a new population in a site with little effort, and then you can use other methods to spot individuals. You can also try to pinpoint a calling male by scanning with the bat detector, but I find this difficult, especially if populations are dense and there are many calling males nearby.

A calling male Long-winged Conehead.

A trick to make them expose themselves is to move your hand slowly around and behind the grass and watch as they respond by moving round away from your fingers, and making themselves visible to you, like so:

This way I can check the shape of the ovipositor, which distinguishes this species from the Short-winged Conehead, without needing to capture the individual.

 A female stops basking and cleans her ovipositor.

Habitat. This is a very generalist species, and I find it in sites where there are not even grasshoppers. Any patch or strip of tall grass, including ungrazed grassland, reedbeds, brownfield sites, river or ditch banks, roadsides or verges and even heaths can hold populations. Rough grass appears to be colonised rapidly once mowing stops.

A plot of land in the city that hasn't been mowed in a couple of years with a population of Long-winged Coneheads.

Long-winged conehead basking.

Urban bush-crickets: Roesel's Bush-cricket

I'm starting a daily series on urban bush-crickets. Checking through the blog, I realised I haven't paid much attention to these newly arrived species in the city. In 2022, I undertook a survey of urban bush-crickets, after I was made aware of the presence of several species in the city of Hull. It was an exhilarating summer: armed with a heterodyne bat detector, I explored grassy areas, marshland and brownfield sites across the city, listening for them or trying to spot them. The last two summers, I have continued with the surveys, as I have really got the bush-cricket bug! With this series, I want to write what I wish I had known when I started regarding each of the species.

Female Roesel's Bush-cricket basking, Rockford Fields, 9 October 2023. Note the curved, relatively short ovipositor and short wings.

The Roesel's Bush-cricket, Roeseliana roeselii, is a stocky species (top shot, a calling male at Sculcoates Cemetery, 28 September 2024). On first impression, if you see one scuttling through grass you think it's a small toad, as they physically disturb the vegetation with their bulk as they move. The size and colour is variable. The most common form is brown and yellow, with some green touches, but some individuals can be very green. The rim of the black side of the saddle-shaped thorax is white, yellow or green. Three yellow spots just above the base of the legs, on the thorax, are distinctive, as is a black comb-shaped stripe across the jumping legs. The species is wing-polymorphic. Nymphs growing in dense populations tend to develop long wings and are able to fly long distances. The long-winged form is responsible for long-distance dispersal and colonisation of new areas. The most common form has short wings, extending half way through the abdomen, and is unable to fly. Females are larger than males and have a short ovipositor, curved upwards. Males have modified forewings, which they use to sing (stridulate). They lay their eggs in plant stems. During mating, males provide females with a nuptial gift called 'spermatophylax' which makes a substantial proportion of males' weight. 

A male long-winged Roesel's form calling.

Behaviour. Individuals like to bask in sunshine, often quite exposed, especially in cool mornings in the autumn. Sometimes they will stretch out a jumping leg to expose the abdomen to the sun. Males start to sing while basking, choosing grass tussocks as a perch. Tussocks offer individuals protection from predators: at the slightest disturbance, they drop onto the base of the tussock and scramble into it. They are not particularly social and will compete for a good perch or sunny spot.

Roesel's are very well camouflaged in their environment and can be tricky to spot. Try to find a calling male Roesel's male from a perch on tall grass. (tip: the Roesel's is at the bottom third of the centre of the image. There is also a Long-winged Conehead on the centre top third.

A typical urban unmown field holding Roesel's.

Habitat. Thought to be associated to salt-marshes and dunes, the species has been shown to be little limited by habitat and can now be found along road and path verges, grassy fields, brownfield sites, and any habitat that includes rank grasses. 

A Nymph Roesel's busch cricket. 28th May 2023, my first observation of the year for the species.

Field craft. How do you find Roesel's bush-crickets? The first nymphs appear in mid to late May. Nymphs can be found by sweeping grass with a net. Adults appear at the end of July, and are best searched for. Male's stridulation is within the human audible range, but it is a high-pitcher whirr, that is easier to hear for children. Many middle age people are unable to hear them at all, so using a bat detector set to 20 KHz makes it easier to detect them. The call is a continuous whirr that has been compared to an electric buzz. Once you are close enough so that the sound is quite loud, you can try and pinpoint where the calling male is perched by swaying the bat detector left and right and up and down. I find binoculars very useful, to scan suitable perches from a couple of meters with minimal disturbance to spot individuals. With a bit of luck, once located, using slow movements, they can be approached to close range. Males tend to call during the day in sunny weather, unless they are already warm, then they will carry on calling. Searching at suitable sunny spots for basking individuals can also be rewarding, especially on bramble leaves next to grass, where they can be more obvious. Roesel's season winds down as October progresses and the last adults die off with the first frosts, their eggs surviving in grass stems over the winter. 

A long-winged female Roesel's. I saw it flying and landing on the short grass of a playing field (31st July 2020), this is the only photo I took, as it immediately flew north. 

Range expansion. Roesel's have undergone a spectacular range expansion in the last decades, from the south east corner of the UK. The first record in Hull was in summer 2015. They are now widespread in East Yorkshire and the northernmost populations are currently in North Yorkshire (at Robin Hood's Bay), but the colonisation is ongoing, aided by climate change and by long-winged forms that appear once population density is high.

A mating pair of Roesel's Bush-crickets. The female is much larger and above, whilst the male hangs underneath the female.

A female eating the spermatophyllax.