Tag Archives: Bug House

An experimental Bee House

Last year, I watched, fascinated, as Mason Bees (Osmia bicornis) made nests in tubes in a commercially produced Bug House situated in a local community garden, the Leechwell Garden. This Bug House is meant to be educational and so has been placed in a prominent position. This brings with it the risk that it will be subject to some attrition; indeed the removable tubes were tampered with both last summer and this spring and the Bug House was knocked off the wall twice during the winter.

I wanted to build another Bug House for the Leechwell Garden to be put in a less vulnerable place but it proved impossible to find a suitable position. I went ahead anyway and placed the new Bee House at the bottom of my garden which is about 100 metres from the Leechwell Garden (as the bee flies).

Experimental Bee House beginning of season
The Experimental Bee House at the beginning of the season (March 2015). I hope you can see the two vegetable boxes with the sides of the top one insulated with recycled vinyl floor covering, also the protective roof. Two cassettes with tubes are in place in the insulated top box . The garden still looks dormant although a few daffodils are visible.

 

My aim was that this experimental Bee House should be made from recycled materials so that it could be replicated by others at minimal cost. I looked around for suitable materials and one day as I was passing the Totnes shop of Riverford Organic, our local organic grower, I saw some vegetable boxes in the window. These looked ideal to make the body of the Bee House so I contacted them and they kindly gave me two boxes. The boxes were not fully sealed, needing insulation and rain protection, so I went to CarpetRight in Newton Abbot and they kindly gave me some samples of vinyl floor covering. I used these to insulate the sides of the new Bee House and to give it a roof. I found some logs, stones and bricks to provide ballast and stability as well as providing potential homes for insects. I sited the new Bee House so that it caught the early morning sun.

I wanted to provide tubes for the bees to nest in and had hoped to use inexpensive bamboo canes from the garden shop. Although I was able to cut up the canes, I found they were filled with soft material and unusable. I, therefore, had to buy solitary bee tubes from Wildlife World, my only outlay.

Experimental Bee House Cassette
One of the cassettes holding the bee tubes. The tubes are organised in to an old mineral water bottle and secured with a cable -tie. Four of the tubes contained mason bee nests from last year.

 

The tubes were organised in to cassettes. Each cassette was based on an old mineral water bottle cut down below its spout but long enough to protect the tubes. About 20 tubes were placed in to each cassette and these were secured using a cable-tie. I put out two cassettes in March, each containing four tubes with nests from last spring in order to give the new Bee House a start. A third cassette went out on May 28th when I thought the bees needed extra capacity but only two tubes were filled.

Experimental Bee House end of season
The end of season view. In two cassettes most of the tubes have been filled, in one cassette put out later two tubes were filled. Some tubes where the seal was broken have not been refilled.

After I had made the cassettes I read that plastic is a poor choice because it is not breathable but by that time it was too late to change design. Despite this, the new Bee House seemed to have functioned well and many of the tubes were filled by hard-working female bees during spring 2015. This is described in the previous post.

Successes and failures with this year’s Red Mason Bees

As we humans continue our lives and perhaps savour the prospect of settled warm weather and holidays, the busy part of the year is already over for the solitary Red Mason Bee (Osmia bicornis). These important pollinators began their activity in early spring and have now built their nests and laid their eggs.

Last year I was fascinated to watch some of these bees in a Bug House in the local community garden (The Leechwell Garden). This year I kept a closer eye on this colony to try to understand their behaviour. I also built an Experimental Bee House at the bottom of my South Devon garden and watched the bees build nests. [I realise not everyone is interested in constructing new bee houses so I have described this in the next post.]

This week is Pollinator Awareness Week so it is especially important that we think about how to protect and encourage these pollinating insects.

The males emerge and misbehave

male Osmia
Male Red Mason Bee

 

Both Bee houses contained mason bee nests (in removable tubes or in wooden blocks) constructed a year ago. The removable tube nests overwintered in my garden shed and were put out again on March 6; twenty four filled tubes and some empty ones went in the Leechwell Bug House and eight were put in the new Bee House. The wooden block nests stayed out all winter as they are an integral part of the Leechwell Bug House; they may have suffered damage when the Bug House was dislodged from the wall.

Osmia on Bug House
Male Red Mason Bee resting

 

I watched the tubes carefully from mid March and was very pleased to get the first hint that a male had emerged when, on April 16th, I noticed that one of the mud seals had been broken. The day before had been very warm so perhaps that encouraged the bees. Over the next week, I began to see males flying about near the two Bee Houses. Fresh males are very beautiful: about two thirds the size of a honeybee and with long antennae, they have vivid orange abdominal hairs, a fringe of beige hair around the thorax and a very distinctive pale “moustache”. Some look a bit different: they have few abdominal hairs and look rather shiny.

Osmia shiny type
Shiny type

 

Osmia feeding from Forget me Not
Male Red Mason Bee feeding on forget me nots

 

The numbers gradually increased over the next two weeks and on sunny days there would be a cloud of male bees near the Leechwell Bug House (perhaps as many as 30) behaving in a very characteristic way. They would fly about, swinging from side to side rather like a metronome, sometimes stopping to look in to a tube, sometimes flying off to feed on nectar. They would also “bomb” one another, especially another male that had stopped to rest or to warm up. I saw one male try to pull another out of a tube and, once his friend was out, he tried, rather unhelpfully, to mate. The cloud of bees would work themselves in to a frenzy when it was very sunny or when a male/female mating pair was present, perhaps they could they smell other females.

Osmia looking out
It’s too cold for me ……

 

All this activity would stop when the temperature fell to 11oC or lower. The males would retire to the tubes in the Bee House, sometimes two or more in one tube where they would look outwards waiting until the conditions improved. Other bees such as the Hairy Footed Flower Bee continued to forage at this temperature and the disparity may have something to do with size, the larger insect being able to tolerate the lower temperature.

Some females and some mating

mating pair April 28 15 2
Mating pair with mites

 

Mating pair with other bees May 7 15
The stillness of the mating pair and the frenzy of the other males.

 

I didn’t witness any females emerging from their nests but I knew that had happened when I saw mating pairs on April 28th and May 7th in the Leechwell Garden. This was an exciting moment as it was a first for me. I was amused to see the female in the first pair decide to go walkabout; the poor male had no option but to sit there even when dragged in to a hole smaller than comfortable for two bees. My excitement was tempered by noticing many mites on the first mating pair which I suspect is not good news for the bees. The latter mating pair did not have the mites as far as I could tell.

Males near the end

worn out bees

Some of the males continued to patrol the Bee houses up to a month after emerging, ever hopeful of finding a receptive female. By this time they were wizened and black and didn’t look like red mason bees any more apart from their white facial hairs. Perhaps we would also look sickly if we fed on sugar alone. They disappeared altogether by the end of May.

Hard working females

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The first pollen-loaded female.

 

May 12th was another exciting day as I saw chrome yellow pollen on the floor of the Bee House at the bottom of my garden for the first time: I now knew that the females were busy building nests. The females are also distinctive and very beautiful, about the same size as a honeybee and larger than the male with, on their head, two horns which they use for tamping down mud. They lack the pale “moustache” but like the males, their abdomen is clothed in vivid orange hairs when freshly emerged.

Female Osmia bicornis
Female red mason bee. The horns are just about visible.  Her colour has faded and a better view of a fresh female with her orange hair is seen in the mating pictures.

 

I watched the females returning after foraging, buzzing loudly and entering tubes head first. After a short time they reverse out, turn round and back in to the tube. I am not sure what is happening here but I witnessed the behaviour many times. Once this elaborate manoeuvre was complete they flew off for more. I also saw one female building a mud partition. She added mud to the inner surface of the tube and gradually, over several trips to collect mud, built the partition inwards keeping it symmetrical and circular before sealing it off.

Throughout the season, there seemed to be plenty of forage about and no shortage of mud for nest building. For both Bee Houses I saw females continuing to fill tubes in to the third week of June.

Problems

In both locations, the number of females seemed very low, especially as there were plenty of males. Last year most of the tubes and wooden block holes in the Leechwell Bug House were reused by females who cleaned out the mess before re-provisioning them. This year the females did reuse old tubes but seemed to prefer fresh tubes when available. In the Leechwell Bug House I saw only two females but they filled more than twenty tubes. Males emerged from the wooden block nests but none of these was reused. At the bottom of my garden there were at least four females and they filled twenty four tubes. In both locations, the mud seal on some of the tubes remained intact and neither males nor females appeared.

Osmia housekeeping
Housekeeping

 

End of season view
End of season for the tubes in the Leechwell Garden Bug House. Many are filled, a few have not been reused and a few have not been used at all.

 

I don’t know why this year has been less successful but I wonder if the tubes were tampered with at a critical time. I know that some were stolen last summer so I presume that, at that time, many of the tubes were disturbed. I also suspect that the tubes in the Leechwell Garden were tampered with again in March this year. Perhaps this double interference damaged the developing females. The Bug House also fell to the ground twice and perhaps the wooden block nests were damaged. Another possibility is that mated females were produced but decided to go elsewhere.

A third possible explanation would be that the old tubes had been infected with another organism that damaged the developing bees.

I opened up the wooden block nests to see if I could glean any information about these problems. None of these had been refilled this year, whereas last year they were all reused. The wooden blocks were very messy: I could see the individual cells made by the bees but there were no intact dead bees. The nests were filled with a brown dust although within this dust I could see dead larvae. It was also clear that in many cases the mud partitions between cells were still intact. There had clearly been a major problem with these nests and I suspect that they may have been infected. The bees avoided these nests so they seemed to know that something wasn’t right.

I am beginning to think that new tubes should be supplied each year to make life easier for the bees and to avoid build-up of contamination.

Now it’s important to leave this season’s nests so that the eggs can develop and grow in to larvae. I need to wait until late autumn before moving them.

Overview of the year

It’s been another fascinating season of Mason Bee watching and as before I have been enormously impressed by the hard work and ingenuity of these bees, especially the females. The males have only one purpose but they seem to do it well.

Watching these bees is not only a fascinating experience, it also makes you aware of the interconnectedness of the natural world. The bees depend on flowers and the flowers depend on bees. We mess with these relationships at our peril and perhaps we understand our own place in the world by realising this. The highlight of season for me was seeing the chrome yellow pollen for the first time. It signified that everything was working; females had mated and were visiting flowers to continue their species. Fresh yellow pollen has a colour like no other, it seems to glow with the energy of sunlight and signifies the unfolding spring.

Please don’t put your foot on our Bug House

crocus March 15

It’s nearly a year now since I began watching some solitary mason bees (probably Osmia bicornis) in the Leechwell Garden, the community garden in the heart of Totnes. I was entranced as I watched the mated females building their nests in the removable tubes and in the holes in the wooden block of the fine Bug House attached to one of the old walls. They taught me so much about the life of a solitary bee.

 

Bug House Oct 14
The Bug House in October 2014 showing the removable tubes above and the wooden block nests below.

The Leechwell Garden is a public space and the Bug House is meant to be educational so it is understood that there will be a certain level of attrition. Sometimes visitors disturb the removable tubes and a few have been knocked to the ground (the tubes that is!). Last summer about half of the filled tubes were taken which is a pity as the developing bees probably did not survive. Anyway, by the autumn of 2014 there were about 30 filled removable tubes still left and I began to wonder whether they would make it through the winter.

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The removable tubes with one of last year’s mason bees and a friend. A newly filled tube can also be seen with its fresh mud seal.

 

I thought long and hard about what to do and decided it would be better to store the tubes somewhere safer. They need to stay cool all winter so I put them in our shed which is not attached to the house. I carefully noted which was the front end of the tubes and stored them in a cardboard box with holes to allow air to circulate. I waited until October 15th last year to do this so that the bees had entered the pupal stage and would not be damaged by moving. The nests in the wooden block, of course, stayed with the Bug House in the Garden.

I can’t say I felt comfortable about doing this, it felt as though I was tampering with nature but I convinced myself it was for the best. The way things turned out, it was just as well I had put the tubes somewhere safe.

Around Christmas time, the Bug House was knocked off the wall, probably by someone using it as a step to scale the wall out of hours. It was put back, only to be knocked off again, this time early in February. With the help of Susan Taylor and of David Martin, who in fact did all the drilling and screwing, the Bug House was put up again but this time at a place I judged to be safer, higher up and away from potential scrambling routes in and out of the Garden. The Bug House has survived two falls showing it is quite tough, but I am concerned about the effect on the bees in the wooden blocks where several mud seals have been lost (see photos below); time will tell if the bees have survived.

Bug House Feb 15
Back on the wall again!

 

Tubes March 15
The removable tubes after the winter.

 

With the winter nearly over and warmer weather in prospect, it was time to put the removable tubes back in their rightful place. Although I don’t expect to see the bees hatch until April, all the advice is to get the tubes in place by early March so that they can acclimatise and warm up slowly with the weather. So, on March 6th I opened up the box and put most of the tubes back in the Bug House. I was careful to put them back in the correct orientation so that the males can make their way out first. I saved a small number to put in an experimental Bee Hotel that I’ll describe in another post.

Tubes March 15 2
The removable tubes back in the Bug House; the majority are filled, a few empty ones have been added.

 

Block Feb 15
The wooden block nests in February 2015 showing that several had lost their mud seals, probably as a result of the disturbance. Compare with the picture below from October 2014.

 

Block Oct 14
The wooden block nests in October 2014 showing the neat mud seals.

 

With the tubes safely back in the Bug House I began to look around for potential bee forage. At present there are a few flowers in the Leechwell Garden, a little rosemary, some crocuses and several clumps of pulmonaria and I have seen honeybees enjoying the rosemary on sunny days. Also in one of the adjacent car parks there are some grassy banks populated with dandelions and celandines. The dandelions are very popular with honeybees. Also one of our neighbours has a striking deep pink, ornamental plum (Prunus mume beni-chidori ) which is currently in flower and when the sun shines there is a gentle, sweet fragrance and the bees flock to it; I have seen honeybees and one bumblebee.

Honeybee on rosemary
Honeybee on rosemary

 

Honeybee on dandelion
Honeybee on dandelion

 

It still feels quite early in the year and the weather seems stuck in a cool phase, but there is some forage about and on a sunny day the bees know how to find it. By the time the Osmia hatch out, which should be mid April, there will be plenty more forage about to keep all the bees happy.

Honeybee on prunus 1
Honeybee on prunus

Short on colour, high on drama – the garden at the turn of the year

How quickly time passes! It’s already a year since I wrote my first post about the Leechwell Garden, the community garden in the heart of Totnes. Each month I’ve written about the plants and the wildlife and it’s been fascinating to watch the Garden change with the seasons.   I’ve learnt so much and also met some wonderful people both here in Totnes and in the blogosphere.  (here is a quick link to these articles)

sage
A sage bush on a rare sunny day

 

I visited the Garden several times at the end of December 2014 and at the beginning of January 2015. I was particularly interested to see how the present state of the Garden compared with what I saw a year ago. I found, just like last year, an overall look that was monochrome, especially on dull days. The trees were mostly bare skeletal branches and there were very few flowers at this low time of year.

rose hips
The shrivelled black rose hips

 

It wasn’t exactly the same, though. A year ago, I found more colour. Last year, yellow crab apples were still gracing their tree in late December. This year the fruit disappeared several weeks earlier, partly because of the attention of the birds. Last year I was taken by the mass of bright red rose hips on the pergola. This year these are almost uniformly black and shrivelled. Perhaps this is due to the mostly mild, mostly damp weather.

holly
Holly

 

olive tree
The olive tree

 

Looking around for more winter interest this year, I found a variegated holly with its leaves shining in the sunshine. The olive tree looked very healthy but I doubt we shall be seeing single estate Leechwell Garden Olive Oil anytime soon. A nearby sage bush also stood out. Near the water I found several mahonia with their frothy lemon yellow flowers and for a short time I watched a visiting insect which I think was a hoverfly.

Hoverfly on mahonia
Mahonia with insect

 

bug house
The bug house. The wooden block mason bee nests are visible towards the bottom of the picture

 

The Leechwell Garden is normally a quiet place but towards the end of December there was drama. The Bug House was found to be damaged and had to be removed for repair! Apparently, someone had tried to climb in to the Garden when the gate was locked. They probably steadied themselves by standing on the Bug House which gave way under their weight. But all is now fine; the Bug House has been mended and returned to its rightful place. Fortunately, the removable tubes containing mason bee nests had been put somewhere for safe keeping over the winter and the wooden block nests seem to be undamaged. The new bees should be flying in a few months.

What we don’t know, of course, is what happened to the intruder.

lungwort
Lungwort with buds

 

Early January does feel like a low time of year and some of this feeling may be due to expectations raised but ultimately unfulfilled by our over-commercialised Christmas. The Garden does not reflect these feelings and if you look around, there are hopeful signs of the new growing season everywhere. Several trees are now veiled in a haze of small catkins getting ready to spread their pollen when the wind and the time are right. The clumps of the bee-friendly plant lungwort may not look particularly attractive at this time of year but they are already showing several stems with large buds. There will be flowers in a few weeks. I even found a few yellow flowers on a clump of primroses.

primrose
Primroses

 

Some of the most striking signs of the new season can be seen on the crab apple tree. From a distance its smooth branches have seemingly been invaded by regular short spiky outgrowths. These will be transformed in a few month’s time by blossom and leaves. Close up, we can see the intricate but beautiful textures of these buds and their rich, reddish-brown colour.

crab apple buds
Buds on crab apple

 

Postscript:  I can’t keep up with Nature! I  wrote most of this post earlier in the week and should have hit the publish button then.  On a quick walk through the Garden this morning I saw several pink flowers on the lungwort and the first frogspawn in the watery area.

frogspawn
I did not have my camera with me on the 16th when I first saw the frogspawn. Here is a picture of the frogspawn taken on January 18th when there was much more compared with two days earlier.

 

A solitary bee story

The boys were hanging around aimlessly although a few did go in to investigate. Some seemed to get bored; they buzzed off for a short time but were back soon, as if they anticipated some action. There was jostling,  a bit of play fighting, but on the whole they waited patiently for the girls to emerge.

This might sound like the antics of a group of teenage boys but I am actually by the Bug House in the Leechwell Garden in Totnes, delighting in the behaviour of the bees. For several weeks I have been watching, hoping that I might spot some of the occupants when they emerged this spring. I knew that solitary bees had used the many of the bamboo canes last year judging from the visible mud filling. I had also seen leaf cutter bees sealing a few of the canes with pieces of leaf, so I had high hopes.

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The rather messy tubes, some still occupied, with one mason bee

By the third week of April many of the mud seals had been broken so I was pretty sure that some new bees had hatched and I did see a few bees hanging around the bug house. Then on the 29th April, I visited the Garden and got quite a surprise. Many bees were flying around the bug house, going in and out of the holes bored in to the wood and to a lesser extent the bamboo tubes. Some flew off but seemed to return quickly. Sometimes there seemed to some aggression between the individuals, although I could be imagining this!

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No, I’m going to get there first!

The bees seemed to fall in to two groups, some were stripy, the others darker without stripes. Both seemed to have lighter “noses”, a bit like a small brush or moustache.

P4290014
One of the stripy bees with its pale “moustache”
P4290015
A darker bee but the pale “moustache” is visible

The next day I had another look and the same bees were there but I had the impression that the darker ones were displaying a preference for one of the bamboo tubes, hanging around and even going in to the tube for a short time.
From my photographs and given the huge number of possible solitary bees, I wouldn’t want to be definitive in identification but I would guess these are mason bees (Osmia sp.) and the stripy ones might be red mason bees. It is also likely that the bees I saw were the males who hatched first and were waiting to mate with the females when they emerged.
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A non-stripy female, note the lack of pale nose hair

 

By May 10th the principal bees going to and fro were slightly larger, they lacked the pale nose hairs but had a distinct fringe of pale hairs around their abdomen. The abdomen itself was dark but clear striations were visible. On May 12th I had a further look and, particularly when the sun shone, there was much movement with the larger bees going in and out of the tubes and one cleaning away old mud. I assume these are mated females beginning to make nests. A few of the smaller males were also still present.

Susan Taylor told me that about the same time she had seen these bees mating.

A few days later (May 15th) it was another warm sunny day, and the bees were very busy, coming back frequently, some clearly laden with bright yellow pollen. By eye there seemed to be one kind of bee but my photographs reveal differences; again there seem to be two populations, stripy and non-stripy.

P5120001
A stripy female with “friend”. Bees are often seen resting in their tube, especially on a cooler day. One tube has been newly filled with fresh mud.

By May 16th some of the tubes had been filled and sealed neatly with mud; four days later almost all had been filled. A filled tube will contain several cells, each containing an egg with pollen and nectar. Cells created first contain fertilised eggs that will produce female bees, the later cells contain unfertilised eggs to produce males that will emerge first next spring. For more on the life cycle of these bees take a look here or here.

P5180014
Most tubes filled!

I can’t help but be impressed by the industry of these creatures. They work very hard transporting mud and pollen to fill the tubes to ensure their survival.      They fly for a few weeks and once the nest is complete their job is finished, until the next spring.   Don’t forget that all the time they are flying, they are performing an important job pollinating our trees and flowers.

For more on mason bees there are interesting posts with much better photos on A French Garden and its sister site Bees in a French Garden.

Thanks to Hazel Strange for tidying up my photos.

The late December garden

Late December is a paradoxical time with its short days and its gaudy celebrations. Even when the sun shines, the light is low and combined with the early arrival of evening, I feel the urge to hibernate. It’s a low time, suitable for contemplating the past year but not quite time to think about the new one.

Emily Dickinson expresses some of these thoughts in the first few lines of one of her poems:
There’s a certain Slant of light
Winter Afternoons –
That oppresses, like the Heft
Of Cathedral Tunes –
……………………………………………………………………………………………..

On two rare sunny days at the end of 2013 (December 26 and 31), I went to the Leechwell Garden in Totnes to see how nature was reacting to this low time. The Leechwell Garden was created in 2010 from a derelict plot of land that had been, for many years, an orchard. We can see the Garden clearly from our kitchen; we watched with interest as it took shape and became a community space. It’s now an important part of Totnes life and used by many.

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The Garden entrance and the pergola

Planting in the Garden has been very carefully planned to provide flower forage for insects throughout their busy time. There is also a Bug House which some solitary bees have used for their overwintering larvae; I await the hatching of the new bees later this year. Most likely there are also bumblebees in the Garden. They would be expected to be safely hibernating at this time of year but in the past week or so I have seen fat bumblebees out and about elsewhere in Devon and in Dorset.

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The Bug House with an unexpected visitor

On the days I visited the Garden, the sun shone from a cloudless pale blue winter sky. The recent weather had been very mild but also wet and windy so the paths were treacherous. I didn’t expect to see any flowers this late in the year so it was a surprise to find a Prostrate Rosemary with some mauve flowers dotted around the mass of dark green foliage and a few pink blooms on patches of Thrift and Heather.

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Heather and Thrift

Despite the paucity of flowers there was colour elsewhere if you looked for it, mainly from the fruits of the carefully chosen plants. The wooden pergola, an important feature of the upper garden, is covered with climbing roses and clematis in summer. One of the roses (Francis E Lester) now shows copious sprays of bright red rose hips, some plump and many slightly shrivelled but all retaining their own natural beauty, especially when seen against the clear blue sky. Elsewhere, a Cotoneaster was covered with red berries which will provide welcome food for birds when times get tougher. At the back of one of the borders, I spotted the distinctive white, translucent seed pods of Honesty, hanging like paper lanterns.

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The most striking sights were the yellow fruit suspended from leafless branches of a Crab Apple (malus), rather like baubles on a Christmas tree. Some of the fruit were intact , some were decaying, swollen and split but they all extended the colour range at this time of year.

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Despite the colours I have picked out, the overall feel of the Garden was monochrome, in tune with this low time of year. It would, however, be a mistake to think that everything is dormant; if you look closely there are clear signs of preparations for the new season. The Crab Apple is covered with buds and I found some catkins on several trees including Silver Birch. They are getting ready for the lengthening of the days and the retreat of the bad weather.

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