It is a magical spectacle of the autumn, swarms of the cranefly Dicranomyia chorea dancing in patches of sunlight towards sunset. These were filmed in Fox Rosehill Gardens in November and I have also seen them in the old parts of the cemetery above Swan Pool in early October. Could they be mistaken for faeries or pixies? I think it likely that they are one natural phenomena that may have supported the folklore.
Saturday, 18 November 2017
Saturday, 11 November 2017
November Wild flowers
November can seem like a rehearsal for winter as the
days shorten, temperatures fall and deciduous trees make their final
preparations for shedding their leaves. It is not though a month entirely of
gloom with Nature snuggling down to sleep through the long nights. A few wild flowers can still be found adding colour to the landscape in the milder
parts of Britain.
The plants I discovered on a walk at the beginning of
the month can be divided into four groups. The first would be the last remnants
of species that mainly flower in September and October such as Ivy and bramble
flowers. The second group are those species that take advantage of
Falmouth’s mild coastal climate to flower for much of the year, examples of
these would be Red Campion and Ivy-leaved Toadflax. A few individual
plants of spring flowering species can be enticed into flowering in autumn by
mild weather, the primroses and wood sorrel flowers I saw for example. Finally there are the winter flowering species that tend to be garden escapees for example Winter Heliotrope.
In all I spotted twelve species flowering, a reasonable count for early November.
Friday, 21 April 2017
Spring arrives
 |
| A carpet of Lesser Celandines heralds Spring |
While the Met Office starts Spring on the first day of March that usually seems premature to me. Yes, there can be days that feel spring-like but others still require winter clothing. The vernal equinox and the changing of the clocks seem about the right time to start raising expectations that Winter is coming to an end.
My two favourite early spring flowers are Lesser Celandine for their bright splash of colour and the more bland Alexander for the reason that it attracts a variety of newly emerged insects to its flowers.
 |
| Male Tawny Mining Bee on Alexander flower |
 |
| Top: Queen Early Bumblebee Middle: Queen Buff-tailed Bumblebee Bottom: Queen Tree Bumblebee |
I spotted my first solitary bee species on the 17th March, with more appearing as we moved into April. The first Cuckoo bee to appear was Nomada fabriciana, a striking bee with a red abdomen and black stripes.
 |
| From Top: Hairy footed flower bee Yellow legged Mining Bee Cliff Mining Bee Cuckoo Bee Nomada fabriciana |
We start this spring with a heightened concern over our butterflies that are showing a decline nationally and in urban areas in particular. There were also indications last year that bumblebee numbers were down and in Falmouth there seemed to be less red-tailed bumblebees about in particular. Fingers crossed that we have better weather this year to help numbers to recover. It is also essential that there will be a continuing source of pollen available to them throughout the spring, summer and autumn. To end on an optimistic note the number of Queen Common Wasps seem to have increased this spring.
 |
| Top: The first Holly Blue Butterfly spotted on 01/04/17 Middle: Queen red-tailed bumblebee Bottom: Queen Common Wasp |
Saturday, 4 March 2017
Bumblebee count No.2
My timetable and dismal weather during my free time this week prevented me returning to the bumblebee nest until a week after my last count. Not that the weather was inviting as I began walking to the site, the dark clouds suggested rain and the strong wind was cold. Not surprisingly I saw no honeybees, hoverflies or solitary bees about. Bumblebees generally shrug off bad weather, they are tough determined little beasts.
 |
| The only other bee seen was this queen Bombus terrestris (Buff-tailed bumblebee) feeding on heather near to the nest. |
As I approached the nest the first question in my mind was, would it still be active? No one knows with certainty how long these winter colonies last. Within a couple of minutes a bee arrived and entered the nest so I began setting up my tripod and camera to film the nest.
Filming the bees entering or leaving the nest offers a number of advantages. From the perspective of personal comfort it is preferable to watch a video in the warm than stand outside conducting the count. If my comfort is of no concern, it also offers greater accuracy as the video can be replayed and examined frame by frame. Having video also offers the possibility of recounts and the availability of other people to view it.
It had rained earlier in the morning and bumblebees have a tendency not to collect wet pollen. Out of the forty bees that returned to the nest only one carried pollen. It was debatable whether the bee had collected the pollen, it was spread on its hind legs rather than rolled into a ball as usual. It returned in the last few minutes of filming and may indicated that the flower's pollen was drying out and some stuck to the hairs on the bee's leg.
The other notable observation was that one worker exited the nest but rather than flying away, turned round and re-entered the nest - see video.
Compared to last week, there were less bees seen in a similar time span. This may be due to several possible reasons. The colony size may have decreased or possibly the bee's foraging activity may have been less due to the adverse weather, wet pollen or the difference in the time of day between the two observations.
The only certainty gained by comparing both day's counting is that more data is needed. It seems I have a new task for next week's to do list.
Bombus terrestris nest - Falmouth 3rd March 2017 11.14hrs+
P/N? = unable to distinguish whether bee had pollen due to hind legs obscured
P/N? = unable to distinguish whether bee had pollen due to hind legs obscured
DUR MINS
|
BEES IN
|
BEES OUT
|
POLLEN
|
NECTAR
|
P/N ?
|
TOTAL
|
10
|
6
|
6
|
0
|
6
|
0
|
12
|
13
|
8
|
7
|
0
|
8
|
0
|
15
|
10
|
5
|
5
|
0
|
5
|
0
|
10
|
11
|
6
|
5
|
0
|
6
|
0
|
11
|
14
|
5
|
6
|
0
|
5
|
0
|
11
|
11
|
7
|
6
|
0
|
7
|
0
|
13
|
7
|
3
|
4
|
1
|
2
|
0
|
7
|
76
|
40
|
39
|
1
|
39
|
0
|
79
|
Thursday, 2 March 2017
Counting Bumblebees in Winter
After watching buff-tailed bumblebees (Bombus terrestris) visiting flowers for the last three winters in Falmouth I have gained some insights into their behaviour but many questions remain. Discovering a nest a week ago will help extend that knowledge a little further. By counting the bumblebees leaving and returning to the nest it is possible to speculate how many bees are in the nest.
Friday 24th February 2017 Bombus terrestris nest - Falmouth, UK
P/N? = unable to distinguish whether bee had pollen due to hind legs obscured
The first thing to consider when looking at the numbers is that about 60% of the worker bees in the colony will remain in the nest doing such things as helping care for the young.
A rule of thumb guide is to take the number seen in ten minutes and times that by four. Taking the peak result would give us 104 bees in the colony with about 42 of these involved in foraging. As can be seen the activity decreased over the time of observations illustrating how varied foraging activity can be. Taking an average of the 10+ minute numbers gives a colony size of 66 bees with 26 workers foraging.
As a ballpark figure we have a colony size of 66 to 104 bees from the initial observations.
Edit 17th December 2017 - Having reflected on these figures I feel they are probably too low. Given that there are fewer flowering plants in winter it is likely foraging flights take longer. Also the frequency of bees visiting plants in various locations suggests a larger colony size although the possibility of there being more than one colony must be considered.
The question is only really going to be answered with a spade once a colony has completed its lifecycle and is disused. Examining winter active nests and looking at its cells where the larvae turn into adult bees will not only give accurate numbers but also answer how many males and queens were produced.
If you are imagining me standing over the nest for eighty minutes counting the bees while examining each to see if they were carry pollen, possibly wearing a deerstalker hat and smoking a pipe you are mistaken. I filmed the nest - the breaks between counts was due to moving the camera and reframing. Counting was done in the warm, watching and replaying the video while drinking copious cups of tea.
Of course I could not resist making another bumblebee video from 80 minutes of footage - don't worry it is only 2 minutes long.
Friday 24th February 2017 Bombus terrestris nest - Falmouth, UK
P/N? = unable to distinguish whether bee had pollen due to hind legs obscured
TIME
|
DUR MINS
|
BEES IN
|
BEES OUT
|
POLLEN
|
NECTAR
|
P/N ?
|
TOTAL
|
14.36
|
12
|
16
|
10
|
5
|
8
|
3
|
26
|
14.49
|
10
|
9
|
9
|
4
|
5
|
0
|
18
|
15.01
|
10
|
6
|
7
|
1
|
4
|
1
|
13
|
15.12
|
10
|
16
|
9
|
5
|
6
|
5
|
25
|
15.26
|
10
|
5
|
6
|
0
|
3
|
2
|
11
|
15.40
|
11
|
5
|
4
|
2
|
2
|
1
|
9
|
15.54
|
11
|
5
|
6
|
4
|
0
|
1
|
11
|
16.06
|
6
|
6
|
0
|
1
|
3
|
2
|
6
|
TOTALS
|
80
|
68
|
51
|
22
|
31
|
15
|
119
|
The first thing to consider when looking at the numbers is that about 60% of the worker bees in the colony will remain in the nest doing such things as helping care for the young.
A rule of thumb guide is to take the number seen in ten minutes and times that by four. Taking the peak result would give us 104 bees in the colony with about 42 of these involved in foraging. As can be seen the activity decreased over the time of observations illustrating how varied foraging activity can be. Taking an average of the 10+ minute numbers gives a colony size of 66 bees with 26 workers foraging.
As a ballpark figure we have a colony size of 66 to 104 bees from the initial observations.
Edit 17th December 2017 - Having reflected on these figures I feel they are probably too low. Given that there are fewer flowering plants in winter it is likely foraging flights take longer. Also the frequency of bees visiting plants in various locations suggests a larger colony size although the possibility of there being more than one colony must be considered.
The question is only really going to be answered with a spade once a colony has completed its lifecycle and is disused. Examining winter active nests and looking at its cells where the larvae turn into adult bees will not only give accurate numbers but also answer how many males and queens were produced.
If you are imagining me standing over the nest for eighty minutes counting the bees while examining each to see if they were carry pollen, possibly wearing a deerstalker hat and smoking a pipe you are mistaken. I filmed the nest - the breaks between counts was due to moving the camera and reframing. Counting was done in the warm, watching and replaying the video while drinking copious cups of tea.
Of course I could not resist making another bumblebee video from 80 minutes of footage - don't worry it is only 2 minutes long.
Thursday, 23 February 2017
A rare discovery - winter active bumblebee nest
Most bumblebee queens hibernate during the winter however towards the end of the 1990's a few winter sightings of Buff-tailed bumblebees (Bombus terrestris) workers were recorded. Winter colonies had previously been known from New Zealand where the species had been imported.
The buff-tailed bumblebee is our most common species but even so winter activity is only known at a few locations in the UK. From the distribution of records the availability of winter flowering plants seems as important as climate if not more so - none have been recorded further north than Hull*.
With few sightings there is still much to be discovered about these winter colonies. For example it is not known how many colonies that produce workers in December and January successfully complete their life cycle - see earlier post, Missing male bumblebees - a mystery?
Although I have been observing Buff-tailed bumblebees in Falmouth for the last three winters the odds of finding a nest were slim. In the end it turned out to a mixture of luck meeting a prepared mind. I sort of stumbled upon it but knew immediately what I had found.
How rare a find is it? To my knowledge the earliest winter nest (December through to February) was discovered in London last December and that is still active to date**. Brigit Strawbridge observed new queens carry pollen back to their old nest in late November 2011 but no males were seen. This was a very late nest to be active, not typical behaviour and possibly a second generation brood. See my post, Bumblebees - A Winter's Tale for more information on second generations. There is also the possibility that the new queens may have founded nests themselves rather than hibernate.
There is still much to learn about this winter activity and it is possibly variable from location to location and year to year. People continue to see winter active workers such as Philip Strange, who has seen them in Paignton for the second winter running.***
Even though the video above is an edited highlights of arrivals and departures it is clear this nest has been established for some time. How long would be a guess but possibly it might be the nest of the workers I began observing in December.
In the video you can see the bees are bringing back different coloured pollen this shows that they are visiting different species of flowers. From the data I collected while filming and intend to collect on my next visit it should be possible to estimate of the size of the colony.
It will be interesting to see how long the colony remains active, current thoughts are that it will reach its end soon but I am keeping an open mind. Towards its end new queens are produced and as they often return to the nest they will hopefully be easier to observe. Males unfortunately leave never to return, indeed recent research suggests they do not remember the location of their nest. I am going to need a bit more luck to spot them.
* See BWARS 2010 infosheet here Click
** Literally a hour after posting the blog I read that the colony was still active (there had been no news of it since December) and have revised this post.
***Read Philip's blog for details of the winter active bumblebees in Paignton. Click Here
Monday, 20 February 2017
Falmouth Cemetery: a haven for wildlife
 |
Possibly the last population in Cornwall of the Red-girdled
Mining bee lives and nests in Falmouth cemetery.
|
When I discovered the old parts of Falmouth cemetery on a casual walk in 2014 I had no idea of its importance as a sanctuary for wildlife. It was clear that there had been minimal maintenance for quite some time. The County Council was responsible for the general upkeep but maintenance of the graves and monuments was the responsibility of the family. Clearly many had been left by the families to go back to Nature. As a result Falmouth had been left a legacy that contained a wide variety of wildlife.
 |
The small copper butterfly has declined by 75% in urban
locations between 1995 - 2014. Another important
species found in the cemetery.
|
For the past two years I have been recording the species of wild bees to be found in the cemetery. While some species can be found elsewhere in Falmouth the scarcer ones seem limited to both living and nesting in the cemetery. Many solitary bees species only forage short distances from their nests, usually a distance of about 50-200 meters depending on the size of each species. So far I have discovered 37 species of solitary bees within the cemetery, some are rare or scare both nationally and in Cornwall.
 |
| Newly emerged Queen Red-tailed bumblebee. Raised in a nest in Falmouth cemetery she visited nearby flowers to build her reserves before hibernating |
The key element why the old parts of the cemetery is able to support such a rich variety of wildlife are the range of wildflowers that grow in the cemetery. From early spring to late autumn they provide both nectar and pollen. The fact that the ground is largely undisturbed also benefits ground nesting species such as most bumblebees.
The value of these parts of the cemetery to both wildlife and the local community is clearly something to be safeguarded. For this reason I have written the document you can download below. It is a guide to some of the species that can be found there together with an overview of the ecology.
While compiling my records for the old parts of the cemetery responsibility for its maintenance passed from Cornwall County Council to Falmouth Town Council. This brought about substantial changes in the way in the way the cemetery is managed. As a response I included a section on maintenance and its importance in ensuring the conservation of the wildlife in the cemetery. Having received a reply from the town council to an earlier draft I have now revised the maintenance section to reflect this.
It is my hope that this will open a debate on how best to manage the cemetery. The maintenance changes are significantly changing both the character of the old parts of the cemetery and its value to wildlife. The degree to which these are desirable are open to discussion. It is important that as many voices as possible are heard in deciding its future.
The current document should be seen as an introduction to the cemetery's biodiversity. During this year I hope to be adding more records to the list of species. I also hope to build a better picture of its butterfly species and also include hoverflies. As its flora plays such a vital part in its ecology I hope to build a seasonal list of its wildflowers. This blog will keep you up to date with my progress.
If you have any photos of wildlife in Falmouth that you would like to share you can be post them on the Falmouth Nature Facebook page or to Twitter including @FalmouthNature.
The current document should be seen as an introduction to the cemetery's biodiversity. During this year I hope to be adding more records to the list of species. I also hope to build a better picture of its butterfly species and also include hoverflies. As its flora plays such a vital part in its ecology I hope to build a seasonal list of its wildflowers. This blog will keep you up to date with my progress.
If you have any photos of wildlife in Falmouth that you would like to share you can be post them on the Falmouth Nature Facebook page or to Twitter including @FalmouthNature.
|
| Click to visit Facebook Page |
 |
Thursday, 16 February 2017
Falmouth buzzes in January
January
is the first full month of winter yet with its mild climate Falmouth still
buzzes. Loudest of the insects to be heard are the buff-tailed bumblebees on
their constant search for pollen. On two days this month I watched workers
foraging until ten minutes before sunset. An indication that their nest lies in
a garden somewhere within the town.Honeybees are not so tolerant of cold weather and only ventured out on mild days in January.
 |
| Honeybee visiting camellia flower |
 |
| Marmalade hoverfly (Episyrphus balteatus) |
 |
| Meliscaeva auricollis |
 |
| Eristalis tenax |
 |
| Red Admiral (Vanessa atalanta) |
 |
| Calliphora vicinia |
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| Scathophaga furcata |
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