Friday, 23 August 2013

Reading Flower Meadows in August 2013

Most of the flower meadows in Reading have survived the heat wave in July but many have suffered and plants have flowered in a shorter period of time than they would normally do. Many of the meadows look like they are at the end of the flowering season now which is a bit of a shame as last year August and September were the months were our annual flower meadows looked best.

Perennial meadows: As the perennial meadows are exclusively consisting of native plants the flowering season is quite short and most of the perennial meadows in Reading have nearly finished flowering now. You can still see some Wild carrot (Daucus carota), Viper`s bugloss (Echium vulgare), Yarrow (Achillea millefolium) and Black knapweed (Centaurea nigra) and in our Portman Road meadow some Wild Marjoram (Origanum vulgare) flowering but the peak flowering time is over now. But even without many flowers the meadows still have their beauty as the bird`s nest-like seed heads of wild carrot look quite ornamental.

An abundance of insect live including many different pollinators are still enjoying the flowers and the shelter the meadows provide. Especially hoverflies are very fond of the wild carrot flower heads, bumblebees visit the last Viper`s bugloss flowers and butterflies enjoy the Wild marjoram.
There are still quite a lot of solitary bees in the meadows
Yellow ragwort and white wild carrot give a nice contrast
Myathropa florea, the batman hoverfly (batman marking on thorax)
A sea of wild carrot flowering in Meadway Recreation Ground
A Common Blue butterfly in our Portman Road meadow
Self-sown Spear thistles are great plants for bumblebees
A not so common ladybird: the Adonis ladybird (Adonia variegata)

Annual meadows: The annual meadows have suffered a lot more in the heat wave than the perennial meadows. Many of the annual meadows are dominated by Corn poppy (Papaver rhoeas) this year which has quite a short flowering season and unfortunately there is not a lot left once it finishes flowering. But there are still some of the annual meadows looking good at the moment, especially the meadows which were sown on moister ground.

The annual meadow in Prospect Park is worth a look as it is dominated by yellow Cosmidium (Cosmidium burridgeanum) interspersed with pink Cosmos (Cosmos bipinnatus) and blue Cornflowers (Centaurea cyanus) which gives a lovely sight. Also the annual meadow in Henley Road Cemetery (Caversham Crematorium) is looking good and very colourful at the moment. The meadow in Christchurch Meadows has quite a lot of poppies flowering and the Victoria Recreation Ground meadow is, despite suffering a lot in the heat wave, still quite colourful.

A beautiful pinkish-red poppy in our Caversham Crematorium meadow
Poppies everywhere in Christchurch Meadows
Poppies glowing in the late summer sunshine
All pink Cosmos and yellow Cosmidium in the Prospect Park meadow
Cosmos, Poppy and Cosmidium
Great colours with Cosmos, Poppy, Cosmidium, Flax and Cornflower
Our meadow in Prospect Park looks beautiful at the moment
The meadow in Victoris Recreation Ground is still quite colourful
Pollinators such as bumblebees, solitary bees, hoverflies and butterflies seem to like the colourful flowers and each time we visited we could see a buzz of activity.

Bumblebees like the Cosmos flowers
A Crab spider on a Cosmos flower caught an unlucky fly
Green-veined white on a Virginia stock flower
This male Bombus lapidarius enjoys the last summer days
The pretty Volucella pellucens

Earlier this month we were visited by Barry Gibb from the Wellcome Trust to film us, the meadows and the pollinators for a documentary about urban pollinators which was quite exciting.

The film is due to be released in Spring next year; we will keep you updated.

Barry filming us during sampling in Prospect Park

To find all of the meadows in Reading please follow this link. For more information about the meadows have a look here.

Wednesday, 14 August 2013

Pollen beetle feeding frenzy!

Pollen beetles (genus Meligethes) spend the winter as adults in soil, emerging in spring to feed on pollen, mate, and lay eggs in flower buds. Oil-seed rape is an ideal spring food source for both adults and larvae, and with an adult female capable of laying 100-200 eggs they can cause substantial damage to the crop. After munching pollen for a month, larvae migrate to the soil and pupate for 2-3 weeks before emerging as adults in mid to late summer – i.e. NOW! In Edinburgh, we are seeing many of these young adult beetles in our urban meadows where they are feasting on pollen from a range of flowers in preparation for winter underground.     

Young adult pollen beetles feeding on cornflower (Centaurea cyanaus)

and on marigold (Calendula officinalis)

and on Californian poppy (Eschscholzia californica)

and on baby's breath (Gypsophila elegans)

and on alyssum (Lobularia maritima)

and on ox-eye daisy (Leucanthemum vulgare)

and on Virginia stock (Malcolmia maritima)

and on poppy (Papaver rhoeas)

Tuesday, 13 August 2013

Identification of common garden hoverflies

Hoverflies are a colourful group of flies (Diptera) which make up the family Syrphidae. Hoverflies are given their name for their characteristic hovering behaviour, and are also referred to as flower flies as they are frequent flower visitors. Adult hoverflies feed mainly on pollen and nectar, making these insects very important pollinators.

There are 270 known species of hoverfly in Britain; these species vary greatly in size, shape and colour. Hoverflies are one of the most common insects to visit our gardens, so are very important pollinators in urban areas. If you have not already read the 30-year wildlife study by Jennifer Owen, I highly recommend you do so! Over the course of this study, Jennifer Owen recorded an amazing 94 hoverfly species in her Leicester garden – over 35% of all British species. Here are a few of the most common hoverflies you might see in your garden – have a read and see how many you can spot this summer…

Marmalade fly (Episyrphus balteatus
This is our most common garden visitor which appears in large numbers between July-August  when large numbers migrate across the Channel from the continent. Episyrphus balteatus was the most common hoverfly species found in Jennifer Owen's study, making up 15% of all hoverflies caught in her garden. It is easy to identify with its orange abdomen and unique double black bands - the only hoverfly to have such markings. 

Episyrphus balteatus on teasel - note the double black bands on the abdomen
Poppies are a popular choice!

Eristalis spp.
Hoverflies in the genus Eristalis belong to the tribe Eristalini. Syrphids in this group are easily identifiable by the strong downwards loop in a major wing vein (see below).

Wing of Eristalis sp. showing strong loop in vein
The most common species in this group is the drone fly, Eristalis tenax. This hoverfly is a good honeybee mimic (hence its common name - a male honeybee is called a drone) which can be found throughout the summer months. There are in fact 9 Eristalis species which are all quite similar - other common species include Eristalis pertinax, E. arbustorum and E. nemorum.  These hoverflies are identifiable by subtle differences in leg colour patterns, abdomen colouration, and the extent of orange triangular markings on the abdomen. Could these curious triangles be mimicking the pinched waist of the honeybee?

Eristalis sp. on Echinacea
Eristalis sp. on Coreopsis - note the orange triangular markings on the abdomen
Eristalis sp. on ox-eye daisy
Honeybee (Apis mellifera) drone: Eristalis hoverflies mimic these to deter predators

Sun fly (Helophilus pendulus)
This brightly coloured hoverfly is very distinctive with its clear yellow stripes on its thorax. The sun fly mimics the social wasp - quite effectively, some might say. Helophilus is a common flower visitor, and can also be found resting on leaves where it may emit a buzzing sound - another form of mimicry to deter predators. Look out for these lovely insects in late spring and late summer.

Helophilus pendulus on hawkbit
Helophilus pendulus basking in the sunshine

Large bulb fly (Merodon equestris)
The large bulb fly (or large Narcissus fly) is a densely hairy hoverfly which mimics bumblebees. There are four main colour morphs which mimic the colour patterns of different bumblebee species. This hoverfly got its name because its eggs are laid on the leaves of bulb plants (such as bluebells and daffodils); once they have hatched out, the larvae burrow into the bulb and stay here for up to 300 days before emerging as adults. You can spot these common garden visitors from May-September - see if you can find all four colour varieties.

Merodon equestris - this colour morph mimics the red-tailed bumblebee (Bombus lapidarius)
Merodon equestris mimicking the common carder bee (Bombus pascuorum)

Common carder bee - can you spot the difference between the model and the mimic?

Long hoverfly (Sphaerophoria scripta)
The long hoverfly is a small, yellow-and-black striped hoverfly with a slender abdomen. There are a few species within the genus Sphaerophoria but this particular hoverfly can be identified easily if you come across a male - its abdomen is significantly longer than its wings. This hoverfly peaks in numbers in July-August and is common in open grassland, gardens (including Jennifer Owen's) and urban wasteland. 

Sphaerophoria scripta on Cosmidium
The long hoverfly: note the elongated slender abdomen

Syrphus spp.
The tribe Syrphini is a very large, diverse group of hoverflies which are notoriously difficult to identify. Within this group, there are many common species in the genus Syrphus, which all possess "moustache" bands on the 3rd and 4th abdominal segments (tergites).  
Syrphus sp. on cornflower - note the moustache bands on the abdomen

Syrphus ribesii is very abundant in gardens, hedgerows and waste ground. Numbers peak in early June and again from July-September.

Syrphus sp. on hawkbit
Thistles provide essential forage for hoverflies

Myathropa florea
This large hoverfly is another wasp mimic with bold black and yellow markings. Myathropa florea is easily identified by the markings on its thorax: a central black patch partially bisected by a pair of pale bars. Adults of this species are fond of large umbellifer flowers, such as wild carrot, and can be seen from May-September.

Myathropa florea: note the pale hairs on the thorax
Myathropa florea are frequent visitors to wild carrot (Daucus carota)
Pied hoverfly (Scaeva pyrastri)
The pied hoverfly is a large hoverfly with distinctive oblique white bars on a black abdomen. This species is very fast-moving, so quite difficult to photograph (from my personal experience!). Scaeva pyrastri can be found in gardens, meadows and wasteland and its numbers peak in August, sometimes being boosted by strong immigrations. 

Scaeva pyrastri - note the oblique white bars on the abdomen

Others to look out for...

Pellucid hoverfly (Volucella pellucens): if this hovers above you, you can see right through it!
Volucella bombylans: a large bumblebee mimic with hairy (plumose) antennae
Platycheirus albimanus: a small hoverfly with beautiful silver spots

Lejogaster tarsata: a small metallic hoverfly. Males are green-bronze and females are blue
If you want to find out more about hoverflies, the best book out there is by Stubbs & Falk - this provides a vast amount of information on the ecology of British hoverflies as well as a fantastic step-by-step taxonomic key and beautiful colour plates to help you get started with your hoverfly ID. You can find out more about the distribution of hoverfly species by typing the latin name or geographical location into the NBN Gateway search tool.