Thursday, 25 June 2015

A garden stretch spider!

It has been so pleasant today, warm and still, with high clouds. I had planned to do a little evening gardening and I was about to start trimming the olive tree when I noticed a busy spider web spinning. Wait, a stretch spider, Tetragnatha, a new spider for the garden! I rushed back home to fetch the camera and took some photos. I think it is a female, possibly adult. Her yellow abdominal stripe glowing with the flash. I couldn't bring myself to capture it for ID as I would have surely destroyed her web and spoiled her night hunt, so I might do tomorrow. I will update the post if I find out what species she is.

Wednesday, 24 June 2015

The patrolling Red Admiral

Since the beginning of June, Red Admirals have been well established, having returned from the Mediterranean in their one way spring migration. Females should be mating and looking for sunny nettle patches in which to lay their eggs. Males should be looking for receptive females to mate with. They will produce one or more broods in the summer. As temperatures drop in the autumn, butterflies will prepared themselves for the autumn migration and then they become very apparent in gardens, where they feed on buddleia and other nectar rich flowers. Male and female have the same wing colour pattern. If you have a good view of the abdomen when the butterfly is resting with its wings open, a swollen abdomen will allow you to identify a female, but otherwise it might be easier to tell them apart by their behaviour in early summer.
 Last week, in the afternoon, I have flushed a Red Admiral from the same sunny spot on a grassy area amongst trees, where they were sitting day after day, exactly where I often found them last year. This afternoon was unusually warm and, as I left work, a Red Admiral sat on a low hedge on a wooded glade teeming with nettles in our university campus (above). It would sit and then fly up patrolling around the trees and chasing passing bumblebees in a similar way a Speckled Wood male would do, and then return to the same perch. I had never noticed this behaviour in the Red Admiral, but it appears that I had observed a male, and that red Admiral males actually defend territories. It might seem hard to believe that beautiful, fluttery butterflies actually engage in any kind of aggressive interaction. Indeed, butterflies have no offensive weapons other than their wings, and, butterfly contests, even when they are defending a territory are often perceived as chases instead of aggressive interactions. However, there is now abundant research showing territorial behaviour in a number of butterfly species. The important point is not the presence of an actual fight but the outcome: as a result of the behaviour the owner remains in the territory and the intruder flies away. Royce Bitzer and Kenneth Shaw studied the territorial behaviour of the Red Admiral on the Iowa University campus. They captured and marked individual Red Admirals with different spots of paint and observed their behaviour once released. They found that Red Admirals spend the morning feeding, but each evening males establish temporary territories for a couple of hours before roosting. Males spent most of their time perched, but occasionally patrolled their territory boundaries. They were not seen feeding. Birds or other butterfly species were chased in a linear way, but male intruders are chased upwards in a spiral. In Red Admiral chases, the owner often retains ownership and the intruder flies away. Good territories are likely to be an area containing resting spots from where passing females can be easily detected, usually with linear features (e.g. a pavement or a few trees in a line). The maintenance of these temporary territories could allow better access to receptive females moving into their roost, as mating is thought to happen in the roosting sites in trees.
A particularly bright red and intact individual, maybe the result of a first local brood?
Two days later a much more faded individual with tattered wings, on the same favoured spot on the grass.

More information
Red Admiral and Painted Lady Research Site. Here.

Bitzer, R. J., & Shaw, K. C. (1979). Territorial Behavior of the Red Admiral, Vanessa atalanta (L.)(Lepidoptera: Nymphalidae). Journal of Research on the Lepidoptera, 18(1), 36-49. here.

Pholcus before and after laying eggs

The first female Pholcus phalangioides laid eggs at the top of the porch last week. The gravid female I was following, which lives under a shelf in the outside toilet was still without eggs yesterday. This morning when I checked, she had laid. Check her abdomen before (below) and after laying (top).

Friday, 19 June 2015

Insects at the University Woodland Area

This afternoon, I joined James Gilbert and Robert Jaques to search for hoverflies, bees and other insects in the woodland area at the University grounds. It was overcast and mild, and a surprising number of insects on the wing. A few Hogweed umbels were a big attractions, as were the buttercups (a handsome Helophilus pendulus above).
The Batman hoverfly, Myathropa florea on hagwort
Nettle tap moth
A male Bombus lucorum swinging from the flowers.
This is a dronefly, Eristalis pertinax.
There were at least three male longhorn, Nemophora degeerella, moths about. They danced as they flew high up. It looks like quite a challenge to fly with such oversized antennae, which presumably attracts the female's attention. This one rested on nettles for a while.
A female Marmalade fly, Episyrphus balteatus, with extended ovipositor.
And to finish, a Speckled Wood. I rarely see these butterflies nectaring. They have a short tongue and like to lap honeydew on tree tops, but the exposed, flat flowers of the hogweed seem to appeal to them.

Sunday, 14 June 2015

A wander for millipedes

We had a walk in our local cemetery today. The eastern part of the cemetery is the oldest and the area has been pretty much left to run wild for many decades. There are huge trees embracing headstones and ivy also covering them, so sometimes it is not obvious you are in a cemetery. It is a muddy and wild place to explore. The cemetery has a lot of dead wood left on the ground and loose stones, which makes it a great place to search for millipedes: today's wild thing.
 We pushed through nettle beds, brambles and hogweed, waded through muddy puddles, crossed others by walking on logs and did a little millipede collection on the way. The wet weather had also brought some interesting fungi.
 Millipedes do often go unnoticed, as they live under the cover of logs, bark and stones, on leaf-litter or in the soil. They have many similar body segments and a pair of legs on each segment. Despite their name, no species reaches 1000 legs. Millipedes have defensive glands and they often open into colour spots on the side of the body called ozadenes. There are about 60 British species of which we found four.
Pterostichus niger ground beetle, centipede, Discus snail under stone.
Tachypodoiulus niger is very easy to identify as it has a black body and white legs. When disturbed it wriggles like a snake. I often find it on dead wood.
In contrast, Cylindroiulus punctatus curls up when disturbed.

Here is once stretched. C. puctatus has a characteristic face mask between its eyes and a clubbed tail end.
In Blaniulus guttulatus the ozadenes are bright red. This species has no eyes and it's thin and tiny
Here are two Blaniulus guttulatus under a stone. They are often found together in large numbers.
A Flat-backed millipede, Polydesmus sp.
The Sycamore embracing a headstone.
A mushroom on yew that looked like mango ice cream.
Lots of Jelly ear fungus.

Saturday, 13 June 2015

A Slug day

As predicted, it rained all night and most of the morning. In the afternoon, the rain turned to drizzle and eventually stopped. This was an ideal day slugs, so my youngest daughter and I went to the wildlife garden to try and see some. Slugs don't have many fans. Many gardeners detest them and fight the slug wars with any means available. Out of the 40+ British species, many of them introduced, some are indeed serious agricultural pests specialising on feeding on living plant tissue. Slugs as a group, however, are ecologically very diverse and most species cause little or no damage feeding on algae, decaying plants, lichens, carrion, or fungi. A few species are earthworm predators. Slugs are not a natural group, they are a mixed bag of snails which have lost their shells: British slugs are the result of four different evolutionary shell loses, each group being more closely related to a different snail family, but more on that on a future post.
 Slugs were plentiful in the garden today and gave a good idea of the diversity of the British fauna. A nice feature of slugs is that they can be easily collected by hand - provided you don't mind getting covered in their mucus - and they are best identified live, so no collecting is necessary (except for some species where dissection is necessary for identification). I tried to get photos of the right side of the slug, with shows the breathing pore and other diagnostic characters, and used the Slugs of Britain and Ireland FSC guide by Ben Rowson and colleagues to identify them. I am no expert, and if you see any misidentification, I will be grateful if you let me know.
 We first came across some large Arion slugs (above photo). These are often active and out and about during the day. The one on the top shot was feeding quite high up on an angelica plant. When disturbed (e.g. poked with a finger), these slugs make a semispherical hump. The first one we came across, a very dark one, started rocking from side to side, a dancing slug was a good start! Only a couple of very variable species, Arion ater and Arion rufus will show this rocking response. Despite its dark colour, this one appears to fits better with Arion rufus, which has a bright orange foot fringe, but Arion often hybridise and species identification is tricky, especially in disturbed habitats.

This was another large Arion, which wasn't as keen to dance:
An Arion adopting its humped defence position.

We found the next slug, the Iberian Threeband Slug, Ambigolimax valentinus, inside an upturned plastic pot, which is fitting as this species is thought to have been introduced initially to greenhouses, but now it is readily found outdoors.
Ambigolimax valentinus

And now to our 'kitchen slug': the Green Cellar Slug, Limacus maculatus. A large, strictly nocturnal species able to squeeze through the tiniest cracks. If you go out into your garden at night, you are likely to see this slug in large numbers. They will often feed on other dead slugs or snails that had the misfortune of being squished on paths during the day. The ones inside our house will feed on cat food if there is any left. This was found together with others under an upturned large plastic tray.

Limacus maculatus
We lifted a few logs and there I found one of my favourite slugs, the Worm Slug, Boettgerilla pallens. I've never seen it in my garden, but it is common in the Wildlife Garden. It is an introduced species first detected in the UK in 1972, when it was already widespread. It was first described from mountain forests in the Caucasus and since then it has spread to western Europe. It is a mainly detritivorous slug, long and thin when moving, reminiscent of a worm. It lives underground, down to 60 cm deep, and moves through earthworm burrows.
The Worm Slug on the log where we found it.

Worm slug on the white bowl.
I got to Deroceras invadens/panormitanum for the next two slugs. Although they look quite different, they look like they have a hump and a truncated tail.

The last one is also a Deroceras, but the tail end is not as truncated, so I got to Deroceras reticulatum.

Deroceras reticulatum

Friday, 12 June 2015

A spider safari

Today for 30 days wild we did a spider safari. Any day is as good as the next for spiders if you ask me, but I am aware there are many people either fearful or wary of spiders. If you are in either of those categories, thank you for reading on, I hope that at the end of the post you look at them for the wonderful and diverse group they are and by understanding them better you might keep a certain level of respect for them, but enjoy them more. All the photos were taken today.
 My daughter found a large cluster of Garden Orb Spider Araneus diadematus spiderlings in between two pots (above). These spiderlings balls are now everywhere (even on my car!). Once they hatch from their silky cocoon, they will stay in a tight ball for a few days in a communal web. After they moult they will disperse to make their individual webs and start catching tiny insects, mostly aphids.
 There are two age groups of Araneus in the garden now. The tiny newborn spiderlings and the year old spiders which have survived the winter and are not mature. This large male has built its web in a flowering sage with is always busy with insects.
Male Araneus diadematus on his web.

A male Philodromus aureolus

 We also found this lovely spider crawling on a hedge, on our way back from school. Males of some crab spiders have iridescent scales on their bodies. I think this is Philodromus aureolus. After failing to take a photos where it was as it was quite mobile, I potted it to photograph at home. Shortly after I released him in the garden I found another individual on ivy, and what could possibly be the female of the same species (below). Crab spiders don't build webs, instead sitting on leaves or flowers to ambush flying insects that stop to bask or feed on the flowers.There are several common Philodromus species, and without microscopic examination of their genitals (or palps in the case of males) identification to species is not possible, which is sadly true for many species of spider.
A female Philodromus sp.

 I searched on some bare ground in the garden and didn't take long to find a wolf spider, a Pardosa, (probably amentata). Wolf spiders don't build webs either, but they move about searching for insects, although they also do quite a lot of basking on sunny spots on the ground. As they don't have a 'home' females carry their egg sacs with them attached to their abdomen, which you can see in the photo below. This photo also illustrates the maternal behaviour of spiders: many species build a cocoon for their eggs, which they attach to a dry corner, or carry the egg sacs with them, or the spiderlings (wolf spiders do this!) or even feed the spiderligs with eggs, regurgitated prey or especial eggs. The most extreme form of maternal behaviour is matriphagy, in which the mother allows the spiderlings to eat her, and eventually kill her.
Female wolf spider, Pardosa sp., with her egg sac.

 Another favourite place for spiders is the log pile. I removed a few logs and found a Blue Lace Spider, Amaurobius similis. A spider that forms a very characteristic form of carded silk and can be found on crevices on walls or trunks or on thick ivy. Amaurobius is one of the bunch of species in which females sacrifice themselves to their first batch of spiderlings, a matriphagous species.
Amaurobius similis. 

 And a few logs later a large female House Spider, Tegenaria sp. House spiders built sheet webs funnelling into corners, where they have a retreat. When potential prey lands on the sheet they come out and trap them. You can entice them to come out by spraying some water on the sheet web. If you see a large spider with long legs in the autumn running around on your living room carpet, or you find one in the bath in the morning they are likely to be a male Tegenaria. They have abandoned their retreats and go about searching for mature females to mate.
Female Tegenaria sp.

 Then it was time to go inside. I have a thriving Pholcus phalangiodes (known as Daddy Long Leg spiders) population in the house. They hang from corners in the ceiling, not moving much. This mature female, which lives under a shelf in the toilet, with her distended abdomen, looks ready to lay her eggs. She will wrap them loosely with silk and carry them in her mouth until they hatch. Then she will sit by her spiderlings for two weeks (presumably not eating anything during this time). Despite their spindly appearance, Pholcus are fearsome predators, capable of subduing much larger and stronger spiders by wrapping them in silk with their long legs.
Pholcus phalangioides, mature female.

Thursday, 11 June 2015

A surprise migrant moth

The afternoon was sunny and pleasant as me and my daughter were walking home from school. We had stopped to watch a tight cluster of garden spiderlings on a hedge, when, from the other side of the street I spotted what I thought was a butterfly moving to feed on a large clump of Red Valerian in the full sun. I kept watching and then I realised it was a Hummingbird Hawkmoth! We crossed the street, let some people walk pass and watched the beautiful moth as it hovered from tiny flower to tiny flower, its long tongue outstretched, sucking the nectar. The light was lovely and the background hard to beat.
 The Hummingbird Hawkmoth is a migrant from southern regions, it overwinters as an adult and it wouldn't withstand British winters. It tends to appear in times of warm weather. I found it a bit surprising, given how cool this spring is being, but maybe migration may happen in response to warm weather in the areas where they come from, and it's been very warm around the Mediterranean. If you see one you can report it to Butterfly Conservation Migrant watch, where you can also see an interactive map with all sightings submitted.
What a treat this was for day 11 of #30dayswild.

Friday, 5 June 2015

A solitary bee quartet

I had so many wild things this summery sunny day that if was hard to settle for an invertebrate group to feature. For lunch I went out with fellow wildlife-lovers Robert Jaques and Callum MacGregor, and tried to capture some hoverflies. Hoverflies were indeed a good candidate for my wild group today as there were plenty, and of many species. Many males were hovering, but a couple of Myathropa florea males managed to sit on my hand, Robert's shoulder and Callums head and avoid the insect net altogether. Episyrphus balteatus, the marmalade fly, were also hovering, and the beautifully metallic Epistrophe eligans. Then I spotted a new spider, with a caterpillar on its web, and then another, would I feature spiders? Then a Red Mason bee started feeding on Buttercups, maybe a wild solitary bee day?
Female Red Mason bee, Osmia bicornis on buttercups. One of her 'horns' is visible at the front of her head. She uses its horns to mould mud she uses to seal her nest.
 Later after work I popped in for ten minutes in the wildlife garden. It was quite warm at the time. A leaf-cutter bee was feeding on thyme, and then chives. Its white and golden mittens flashed as it fed, a Willoughby's leaf cutter bee. Definitely a solitary bee day!
Male Willoughby Leaf-cutter bee, one of the easiest to identify by its front legs, which are covered on white-golden hairs in the shape of mittens, just visible here.

Back home I went to the sage. I had seen a favourite bee of mine yesterday very briefly. Anthophora furcata, a male which didn't settle, patrolling around the sage and the hedge woundwort. This is a rich brown bee with a very long tongue. Males have a yellow face and they have a strong preference for hedge woundwort, but also like several others flowers with deep corollas. Males appear, as many other bees, earlier in the season, settle in an area with their favourite flowers and check other bees, often head-butting them, while in search of females. And there he was, lovely and fresh. He even stopped the frantic patrolling to settle on a sage leaf to bask for a while, its back and face covered on pollen.
A male Anthophora furcata.

As I watched the A. furcata, a smaller bee caught my attention. It was a female Osmia caerulescens. This is a long tongued bee too, females have a bluish tinge and white hairs on stripes on its abdomen. After feeding on the sage, the bee stopped and stretched its tongue several times.
Female Osmia caerulescens

A female Osmia bicornis in the garden on the wallflower Erysimum 'Bowles mauve'.

If you'd like to learn to identify solitary bees, the Bees, Wasps and Ants Recording Society is a wonderful resource. Identification sheets for common solitary bees, often found in gardens are available too. There are 205 species, many hard to identify, but a few common ones are easy to identify once you become familiar with them.