Tag Archives: leafcutter bee

An oasis of calm, a mosaic of environments

Towards the end of July, I visited the Maer, a nature reserve situated at the eastern end of the promenade in Exmouth, a seaside town in the south west of the UK.  With its sand dunes and sandy grassland, the Maer is a remnant of a much larger dune system that once stretched down to the beach. Nowadays, it provides an oasis of calm close to the busy sea front as well as a habitat for special plants and insects.

sea holly growing on the sandy ridge

A slight mist softened the long views as I walked eastwards along Exmouth sea front.  Some warmth penetrated the cloud and a few people were already enjoying the beach on this late summer morning.  The sandy tip of Dawlish Warren lay tantalisingly close across the water and further on, the Ness at Shaldon lurked in the mist like a gigantic wedge of cheese.  The commercial area with its big wheel, pubs and cafes was busy but eventually I reached a quieter part where sand and scrub tumbled downwards at the side of the beach road.  This is the edge of the Maer, a local nature reserve and one of Exmouth’s hidden gems. Superficially, the Maer is a large grassy, sandy space sandwiched between the beach road and Exmouth Cricket Club but it conceals a mosaic of different environments with unusual flora and fauna.

A substantial sandy dune ridge forms the southern border of the Maer giving views across the reserve on one side and towards the beach on the other.  Marram grass grows thickly giving the sand stability but there are also areas of bare sand and areas of scrub, reminders of the dune system that must have occupied this area before the beach road was built.  Restharrow with its pink and white pea-type flowers and a few residual yellow evening primrose provided some colour but it was the sea holly that surprised.   This is an unusual and unexpected plant that grows extensively along the first part of the ridge.  Its spiky greenish-grey leaves with white margins and veins and its powder blue flowers light up the sand as though someone had spilt pale paint.  Sea holly flourishes in these arid conditions by having leaves covered in a waxy cuticle to help retain water and through its deep roots. Although sea holly has some visual resemblance to our Christmas greenery, it is a relative of the carrot; in the past it was employed as an aphrodisiac.

Several large insects with bold black and yellow markings crawled about the bright blue sea holly flowers collecting nectar.  These are beewolves, some of our most spectacular solitary wasps, that nest in sandy places and specialise in catching honeybees.  Both male and female beewolves were feeding that day but it is the larger female (up to about 2cm long) that catches and paralyses honeybees and may be seen flying back to the nest carrying a quiescent honeybee beneath her.  She digs a nest tunnel in sandy soil up to a metre long with multiple terminal branches where she lays eggs and provides honeybees as food for the developing larvae.  These once rare insects have expanded their UK range since the 1980s, possibly in response to climate change and I saw them in several places on the reserve notably on a stand of mauve thistles. They are not aggressive towards humans.

Further along the ridge, before it is colonised by brambles, scrub and low trees, I found a large clump of an unruly scrambling plant covered in pea-type flowers of an impressive reddish-pink colour.  This is broad-leaved everlasting pea, a perennial relative of our annual sweet pea, growing through the grasses on the Maer ridge holding on via thin tendrils.  A chunky dark bee was feeding from the flowers, apparently undeterred by their jerky movements in the breeze. This was a leafcutter bee, most likely the Coast Leafcutter Bee that favours sandy habitats near the sea.  They nest in burrows in vegetated sand lined with pieces of leaf cut from trees and plants.    Later, when the sun came out, I saw several of these bees chasing one another around the bright pink flowers like children in a playground.

The large central part of the reserve was coated with golden brown grass criss-crossed with paths for walkers and looking very dry, a reflection of the recent lack of rain.  Within the grass were mats of restharrow and many of the yellow dandelion-like flowers of catsear.  One area resembled a lunar landscape with many small craters where the surface had been dug out exposing the sand.  Solitary wasps and small leafcutter bees had happily nested here.

Tall clumps of ragwort with bright yellow daisy-like flowers and deeply lobed green leaves were dotted around the central area. This plant provides valuable habitat and food for invertebrates and I found one clump that had been appropriated by black caterpillars with prominent yellow bands.  They were moving about, eating the leaves of the ragwort, voraciously consuming the greenery and destroying the upper parts of the plant.  These are caterpillars of the cinnabar moth and as they feed, they assimilate some of the toxic alkaloids contained in ragwort, rendering themselves unpalatable to birds and other predators.  It is said that their yellow stripes act as a warning to birds.   Once fed and mature, the caterpillars dig themselves into the ground to spend 12 months or so as pupae before emerging as beautiful day-flying red and black moths.  The adult moths live for a few weeks, feeding on nectar before mating and laying eggs on the ragwort leaves.  The eggs grow into caterpillars and the cycle starts all over again.   The cinnabar moth is entirely dependent on ragwort for its survival.

Towards the western end of the reserve, I found a large colony of flowering plants, perhaps suggesting damper conditions.  Clumps of common mallow up to a metre tall dominated with their trumpet flowers composed of five deep pink petals each with purple stripes.  At the centre of each flower was a mass of grey pollen-covered stamens emanating from a single stalk like a miniature bunch of flowers.  Near the mallow, large areas were covered by a sprawling, scrambling plant richly covered with pea-like flowers above many small, spear-shaped, mid green leaves.  Flower colours varied from very pale to light blue, mauve and deep purple with some plants having several of these colour variants.  One plant even had bright yellow flowers.  This is Sand Lucerne, a fertile hybrid of lucerne and sickle medic, naturalised in East Anglia, where its two parents grow together, but now transplanted elsewhere.

There’s so much to see at the Maer and I could easily have spent several more hours looking about.  But I had a train to catch so I headed back along the promenade and across the town towards the station.

This article appeared in the October edition of the Marshwood Vale Magazine.

The picture at the head of this article shows the sandy ridge just above the seafront in Exmouth and the clump of broad-leaved everlasting pea.

 

beewolf on sea holly
male beewolf on sea holly

 

Female beewolf on thistle
female beewolf on thistle

 

Broad-leaved everlasting pea with leafcutter bee
leafcutter bee on broad-leaved everlasting pea

 

cinnabar moth caterpillars on ragwort
cinnabar moth caterpillars on ragwort

 

common mallow
common mallow

 

Sand Lucerne
sand lucerne

 

Watering cans, wild flowers and swifts – looking back at the Garden in July

At this time of year, only a small corner of the Leechwell Garden is visible from our kitchen window; the rest is obscured by the thick green wall erected by the trees. I can still see the three silver birches, also two of the benches and the lower part of the water course, popular with young children who like to paddle, especially during the hot weather we experienced this July.

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red valerian in seed

There had been storms about and we did hear distant rumbles of thunder on more than one occasion but in Totnes this month there was little or no rain for more than three weeks. With the sultry temperatures everything began to look rather parched. Many of the flowers on the red valerian lining the paths near the Garden turned to seed; this felt earlier than previous years. The plants acquired a downy covering of numerous seeds equipped with small parachutes to aid windborne dispersal; no wonder it grows everywhere. I was also surprised to see ripe blackberries – in my mind blackberries are a feature of autumn.

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blackberries

The swifts were an almost constant feature this month, shrieking over the Leechwell Garden morning and evening. Typically there were ten or so probing the air above the Garden looking for insects. On the 21st, the swift spectacular stepped up a notch and we counted more than 40 that evening. I had noticed flying ants in our garden so I wondered if the extra food had attracted the birds.

swifts over Totnes
swifts over the Garden

What is it about the swifts that captures our attention? We have to look, we have to try to count. They speed past our house, they manoeuvre, change course quickly and regroup like miniature spitfires in an old Battle of Britain film. But suddenly, on the 28th we noticed their absence. They had gone, making their way back to Africa for the winter. We miss them.

Down in the Leechwell Garden, one problem this July has been the lack of easily accessible water. There was no actual shortage; water flows freely through the garden but it has to be carried some distance as there are no taps. This was the first prolonged dry spell for some years and I sensed that plant growth was being affected. The Garden volunteers came up with the clever idea of providing watering cans for visitors so that, as they looked around, they could also water the plants. Some of the watering cans are child-sized so watering can become a game.

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The pergola with clematis Perle d’Azur and lavender. The notice urges visitors to help with watering.

On the pergola, purple seemed to be the colour of the month. The later flowering clematis showed well and the path was lined with burgeoning banks of lavender.

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wild flower bank

At the far end of the pergola there is a long wild flower bank. This has been carefully planted and showed a fine mixture of native plants in July – I saw proud yellow-flowered stems of mullein, floppy flowers of evening primrose, peering ox eye daisies, wild marjoram, musk mallow, knapweed, and, towering above them all, spindly purple-flowered verbena bonariensis (native to South America).

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marjoram

It’s very good to see the wild flower bank as it’s one way to provide extra habitat for pollinators. I saw plenty of insects there in the morning but later they seemed to desert this part of the Garden for the attractions of other flowers. One of the competitors was a large patch of golden marjoram covered with white flowers; on sunny afternoons this positively pulsated with honeybees and hoverflies. The beautiful borage also continued to flower well and its starry blooms were well used by bumble bees.

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borage
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borage with bumblebee

 

I want to finish with more pictures of bees and flowers.

 

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scabious with honeybee
July 14 2
I found this marigold with a bee turning in circles rubbing its abdomen around the flower centre. I think this might have been a leaf-cutter bee. I hope so.

The picture of the swifts was taken by Hazel Strange.

A close encounter with a Leafcutter Bee

It had been one of the first really hot days of the year; also the day Andy Murray won the men’s title at Wimbledon. We had been to the coast: for the sea and for a picnic in the early evening sun. When we got back and had unpacked the car, I went in to our garden. We have a Wisteria growing as a small tree in a pot. It had its two weeks of floral glory in May but its copious foliage now demands regular watering especially during hot weather.

While I was giving it a drink, I heard a strong buzzing near my head. Sure enough there was a blackish bee to my right, perched on one of the leaves. As I watched, it deftly cut through the leaf and rose up carrying a leaf fragment between its legs before flying away, rather like a Harrier Jump Jet. I had no camera to record this astonishing (to me) event which was a pity. When I had a look in my book of Small Woodland Creatures, I realised that this was a Leafcutter Bee, one of the UK’s solitary bees and an important pollinator for summer flowers, vegetables and herbs.

Wisteria with Leafcutter hole
Wisteria with Leafcutter hole

Next morning I had another look at the Wisteria, secretly hoping for a rerun of the events of the previous day. I didn’t see any more Leafcutters but, based on their characteristic calling card, it was clear they had been here before on more than one occasion. There were several circular holes (~ 1cm) in the leaves, the trademark of the Leafcutter Bee. When I had watched the bee, the fragment of leaf appeared about the same width as the bee and a little longer, but I believe this is because the bee folds the circle of leaf in to an aerodynamic form.

The Wisteria seems quite happy despite the invasion of the Leafcutters and anyway the leaf fragments are very important for the life cycle of these creatures so we must let them get on with it. Mated females work hard all summer to provide next year’s brood. She makes her nest in holes in plant stems, dead wood, cliffs and old walls. Leafcutters also seem happy to take up residence in purpose built bug houses, but more about that later. The female Leafcutter lines the nest with pieces of leaf and petals and constructs brood cells in the tube, providing each cell with pollen and nectar and laying one egg. She seals the cell with a piece of leaf and then starts on the next cell continuing along the tube until it is nearly full. She then collects many pieces of leaf and puts them at the nest entrance cementing them together to form a solid barrier to protect against all sorts of threats. The young bees develop in the individual cells where they overwinter and emerge the following June and the cycle starts again. There are some lovely pictures and drawings of Leafcutters on this web site.

Bug House in the Leechwell Garden
The Bug House in the Leechwell Garden

By chance, I also visited the local community garden (The Leechwell Garden) that day. The garden has many bee-friendly plants and one of the people who works there showed me their bug house. In one of the tubes was the nest of a Leafcutter bee complete with the neat sealing of leaf pieces. Here is a photo showing the (out of focus) sealed nest tube and the green leaves. I make no linkage between the Leafcutter in my garden and this nest but it is a nice coincidence.

Leafcutter nest
A Leafcutter nest with its sealing of leaves