On a mild almost spring-like day this week I saw my first queen bumblebee of the year. It whizzed by, giving me no chance to practice my identification skills. Later that day I found myself transcribing the phrase ‘Saw a big wild bee’ from a diary entry dated 4th February 1882. I could be no more accurate than a diarist living well over a century ago, who did not have access to the huge array of bumblebee identification material now available to the interested observer of nature.
‘Bees’ have been much in the news in recent years. Everyone likes them, no one likes the idea that modern life is eliminating them and we know we really need them. Politicians and environmental charities have come up with a variety of initiatives to help them, which usually involve planting bee-friendly plants; places where bees of different kinds can come together to share in a feast of nectar or gather basket-loads of pollen.
A story on Inside Science (Radio 4) this week raised the terrifying spectre that these banquets for bees might prove to be bonanzas for two species of bee parasite, which appear to be able to spread from honeybees to our wild bumblebees. We can’t prove that the diseases are spread from honeybees to bumblebees, the scientist interviewed said, but this is likely.
The project had established that the parasites could spread from honey bees to bumblebees in the laboratory. To find out if this was happening in the field, honeybees and bumblebees were collected at the same flower-rich sites across the country, and tested for parasites. High infestations of parasites in honey bees, along with lower levels in bumblebees, were thought to indicate spread from the former to the latter.
I find it surprising that the researchers did not look at parasite numbers in different species of bumblebees. Some bumblebees sip nectar from the same flowers that honeybees use, but others, for reasons of morphology, such as extremely long tongues, or adaptation, do not. The latter should therefore not be exposed to the same opportunities for infection as the former. Would this not be a simple way to test the theory?
My diarist from 1882 well knew the difference between honeybees – he describes going ‘after dark to see a big skep of bees put down’ – and wild bees. The former were the now extinct western black bee which is these days often described as ‘native’, although that is a moot point. Bumblebees are now part of the bee fraternity which we are encouraged to conserve. I hope it won’t be long before natural pollinator bees like lawn bees, and other pollinators like hoverflies, join the club of insects with initiatives to conserve them.
This blogpost was contributed by James Robertson, editor of Natur Cymru.
Natur Cymru is a quarterly magazine about the wildlife and environment of Wales. As of 1st April 2017 Natur Cymru has ceased publishing. We hope this is a temporary situation. Back copies are still available for sale, please see our website for full details and to find out more about Natur Cymru and its role in reporting on Welsh wildlife www.naturcymru.org.uk
Saturday, 22 February 2014
Wednesday, 19 February 2014
Seabird Wrecks
From time to time abnormal numbers of dead or dying seabirds are washed ashore. Such events get referred to as ‘Wrecks’, particularly when adverse weather rather than pollution is the likely cause. After the prolonged series of severe gales experienced on western coasts since mid December, more than the usual numbers of seabirds may be expected to be recorded on Welsh beaches during the annual Beached Bird Survey organised by the RSPB. This exercise was started a couple of decades ago primarily to monitor chronic levels of oil pollution that were then often coming from tank washing or still leaking from the bunkers of vessels sunk in wartime. Nowadays, except when there has been an accident, it is unusual to find oiled seabirds. However, those of us old enough to remember walking beaches in the 1950s may recall that it was unusual not to encounter the remains of oiled auks.
The 2014 Beached Bird Survey now underway is centred on 22-23 February, but records a week either side of this weekend will be included. The survey simply involves walking a length of shoreline between grid referenced locations and recording the numbers of each species that may be found, noting if any happen to be oiled and checking for rings. By pooling data from many beaches in a region it is then possible to derive comparable figures for numbers per kilometre of shoreline.
As might be expected, the numbers washing up on particular coasts vary somewhat from year to year, not just to changing mortality rates in the near shore waters but also on wind directions prevailing in the weeks prior to the count. This year there are already indications that the numbers of Razorbills and Guillemots are going to be higher than normal. The weather is the likely cause, with gales reducing food availability and extra stress while trying to avoid being carried too far down wind. Often in such wrecks the birds are found with flight muscles wasted away as well as having burned up their fat reserves. For the two auks (Razorbill and Guillemot) there are records going back to the 19th century of occasional early autumn wrecks as well as mid winter ones. In the Irish Sea auk wreck of 1969, the primary cause of fatal stress was shown to be problems during the post-breeding moult. After breeding these auks become flightless for at least six weeks while growing a new set of flight feathers. Other species vulnerable to winter wrecks round the British Isles have been Kittiwake (Cardigan Bay, Feb 1959) and Shag.
If early indications from personal observations are borne out by the full survey it seems likely that the species most affected in the waters from which birds have drifted to Anglesey this time is Razorbill. Taking estimates of breeding populations in the British Isles as a rough approximation of expected ratios if Guillemots and Razorbills were equally vulnerable, the expected ratio in body count would be 5 Guillemot to 1 Razorbill. From just the small and statistically inadequate sample I have seen so far the ratio here is reversed. It will be interesting to see if this is borne out when more data is available.
While the number of birds involved may be relatively large, past indications are that this sort of winter mortality will not have much effect on the auk breeding populations in the longer term. Both Razorbill and Guillemot are quite long lived, they do not breed until several years old and there tends to be a pool of non-breeders waiting to take places on the better ledges.
This article posted by Ivor Rees.
Razorbill wreck |
As might be expected, the numbers washing up on particular coasts vary somewhat from year to year, not just to changing mortality rates in the near shore waters but also on wind directions prevailing in the weeks prior to the count. This year there are already indications that the numbers of Razorbills and Guillemots are going to be higher than normal. The weather is the likely cause, with gales reducing food availability and extra stress while trying to avoid being carried too far down wind. Often in such wrecks the birds are found with flight muscles wasted away as well as having burned up their fat reserves. For the two auks (Razorbill and Guillemot) there are records going back to the 19th century of occasional early autumn wrecks as well as mid winter ones. In the Irish Sea auk wreck of 1969, the primary cause of fatal stress was shown to be problems during the post-breeding moult. After breeding these auks become flightless for at least six weeks while growing a new set of flight feathers. Other species vulnerable to winter wrecks round the British Isles have been Kittiwake (Cardigan Bay, Feb 1959) and Shag.
If early indications from personal observations are borne out by the full survey it seems likely that the species most affected in the waters from which birds have drifted to Anglesey this time is Razorbill. Taking estimates of breeding populations in the British Isles as a rough approximation of expected ratios if Guillemots and Razorbills were equally vulnerable, the expected ratio in body count would be 5 Guillemot to 1 Razorbill. From just the small and statistically inadequate sample I have seen so far the ratio here is reversed. It will be interesting to see if this is borne out when more data is available.
While the number of birds involved may be relatively large, past indications are that this sort of winter mortality will not have much effect on the auk breeding populations in the longer term. Both Razorbill and Guillemot are quite long lived, they do not breed until several years old and there tends to be a pool of non-breeders waiting to take places on the better ledges.
This article posted by Ivor Rees.
Labels:
auk,
Beached Bird Survey,
guillemot,
kittiwake,
razorbill,
seabird wrecks,
winter mortality RSPB
Monday, 17 February 2014
After the Storm
Our February storm caused quite a stir, leaving us with no power, no mobile signal and no phone line. The following morning we checked outside; lots of debris, the greenhouse was in tact and just two conifers had fallen at the top of the garden.
We packed a bow saw and headed down the drive, to see if our neighbours were ok, but had to reverse back for the chain saw. I nibbled at the oak lying across the drive, just below the top hairpin, while Sue walked to the bottom. I was still hard at it when she returned to advise there were several more trees she had had to climb over.
We worked our way slowly downhill until we heard the sound of the cavalry to our rescue, two chainsaws ripping their way upwards. A big thank you to Natural Resources Wales for coming to help, having already cleared the bottom lane.
Thanks to BT OpenReach for climbing the poles to replace a hundred metre section of line. Thanks to Scottish Power for replacing several hundred metres of cable – Dewi the farmer had seen the cables on fire with the flames making their way up the hill towards us.
The damage along our side of the valley was immense but everyone emerged unscathed. We were very lucky and we all know our neighbours that little bit better!
Gareth in steel toecaps |
Armageddon on the bottom hairpin |
Thanks to BT OpenReach for climbing the poles to replace a hundred metre section of line. Thanks to Scottish Power for replacing several hundred metres of cable – Dewi the farmer had seen the cables on fire with the flames making their way up the hill towards us.
The damage along our side of the valley was immense but everyone emerged unscathed. We were very lucky and we all know our neighbours that little bit better!
'I'm sure I buried a bone here' |
Just above the bottom hairpin |
Friday, 7 February 2014
The Biggest Twitch
Alan Davies and Ruth Miller of The Biggest Twitch are birdwatchers and expert tour guides based in north Wales. During 2008 they set a new world record when they saw 4,341 different birds during the year.
At 7pm on Saturday 22nd February at the Porthmadog Football Club they will give a talk about their birdwatching highlights during last year in north Wales, Spain, Finland, Norway and Thailand. Entry fee £3.
This event has been organised by:
At 7pm on Saturday 22nd February at the Porthmadog Football Club they will give a talk about their birdwatching highlights during last year in north Wales, Spain, Finland, Norway and Thailand. Entry fee £3.
This event has been organised by:
Labels:
Glaslyn Wildlife,
Porthmadog,
Talk,
The Biggest Twitch
Anglesey AONB Winter Bird Watch
Saturday 15th
February is a date to put in your diary if you would like to see the spectacle
of winter birds on Anglesey. This time last year 100 different bird species
were recorded on the day of the event plus bottlenose dolphins and otters. I
went along to meet Lowri Hughes (the organiser) and Ben Stammers (one of the
bird experts) for a preview of what might be on show at Cemlyn, one of the many
sites to be surveyed on the day.
Lowri and Ben on the shingle ridge at Cemlyn |
Rather than try
to repeat Ben’s descriptions and the overall
atmosphere you can hear what’s on offer on this Sunday’s Country Focus on Radio
Wales. This programme is now available as a podcast for 30 days after
broadcast. Click here for details of the podcast.
The terns
for which Cemlyn is most famous are not due to arrive until mid March, which is
just as well because the islands in the lagoon, where they nest, are currently
submerged. Between now and mid March Ben
and members of the North Wales Wildlife Trust will regulate the flow of water
to make sure there is sufficient island nesting space.
If you would
like to take part please make contact with Lowri on 01248 752 446 or by email
to lehpl@anglesey.gov.uk
The plan is
for everyone to meet at Penrhos Coastal Park car park at 8.15am to split into different
groups, then once the day’s bird watching has been completed, everyone will
meet back at Caffi’r Parc at Breakwater Country Park for some food and a chat about
the days sightings at around 4.15pm.
Islands almost completely under water |
Swept clean?
As well as the coastal erosion and damage to infrastructure caused by the succession of storms and tidal surges this winter, there have been other noteworthy consequences. Anyone who has been to Welsh beaches in the last few weeks will have been struck by the huge amount of litter cast up by the sea. This isn’t just big items like plastic drums and broken fish boxes, but also huge quantities of tiny fragments of expanded polystyrene and other plastics.
In the aftermath of major oil pollution incidents years ago, work was done to model the drift of oil and other things on the sea surface. In general, figures of around 2-3% of the near surface wind speed provided a good approximation for both forecasting drift and hindcasting origins. So, while a waterlogged pallet might drift at about 3% of the wind speed, things with more windage, such as empty drinks bottles with lids, would be expected to travel rather faster. Sometimes, where the origins of objects are known, the speed of travel to reach our shores from distant places can seem quite surprising. An example of this from a few years ago was when identifiable parts of a catamaran, which broke up in a storm off Cape Finisterre in NW Spain, reached an Anglesey beach in 110 days.
Seeing the amounts of debris and particularly the fine fragments of broken up plastic on some Welsh beaches facing the SW wind or where the tidal surges have swept debris up inlets, one is reminded of the poetic musings of the Walrus and the Carpenter, as they walked along a beach before over-exploiting the local stock of oysters. Verses 4 & 5 of the poem as told to Alice in Lewis Carroll’s Through the Looking Glass were as follows:-
It only requires a slight substitution of junk for sand in verse 4, to express the nigh on impossibility of removing the smaller fragments of plastic even by armies of volunteers. Seaborne litter should be getting a higher profile and is now included in the EU Marine Strategy Framework Directive. Thought is currently being given to how best to develop monitoring programmes for the various components of marine litter. Actually collecting and disposing of it is quite another matter.
One consequence of the prolonged sequence of depressions swept across the Atlantic by the jet stream may have been a reduction in the “standing stock” of litter actually washing to and fro out at sea with more of it landing up on the shore. Back of envelope calculations would suggest that 40 days or so, with winds as they have been, might have swept ashore most of the litter from about 700 – 1000 nautical miles out in the ocean. Looking at the organisms growing on the litter, it was noticeable that while the lost whelk pots and other items thrown up from the near-shore seabed by the early storms had the usual range of barnacles and saddle oysters on them, the floating litter coming up then had few attached organisms. Debris floating in the open ocean for long enough usually gets colonised by things like stalked or goose barnacles (Lepas spp.). The occurrence of such organisms can give clues as to whether a proportion of the litter has come from out in the open ocean or from more local sources in and around the Irish Sea. It was interesting to see that photographs showed Lepas on the bottom of the boat on which the Mexican fisherman apparently survived, drifting across the Pacific for many months.
Five species of goose barnacle turn up on debris washing up on Welsh shores. Of these the most familiar is Lepas anatifera. Unusually, at least in Llŷn and Anglesey, L. anatifera has been less common this winter than a smaller species, L. pectinata, which can be distinguished by the obvious radial ribbing on the shell plates. Another species, which can be found sometimes is L. hilli. This one has an obvious pale and often bright orange band where the stalk reaches the shelled part. The fourth species, L. anserifera, which seems to be rare, perhaps partly because it is less easy to identify, grows to be similar in size to L. anatifera but has ribbed shell plates. Finally there are a few records of the buoy barnacle Dosima fascicularis which starts off by attaching to small things like feathers but then goes on to secrete a float of its own.
The author of this blogpost is Ivor Rees.
In the aftermath of major oil pollution incidents years ago, work was done to model the drift of oil and other things on the sea surface. In general, figures of around 2-3% of the near surface wind speed provided a good approximation for both forecasting drift and hindcasting origins. So, while a waterlogged pallet might drift at about 3% of the wind speed, things with more windage, such as empty drinks bottles with lids, would be expected to travel rather faster. Sometimes, where the origins of objects are known, the speed of travel to reach our shores from distant places can seem quite surprising. An example of this from a few years ago was when identifiable parts of a catamaran, which broke up in a storm off Cape Finisterre in NW Spain, reached an Anglesey beach in 110 days.
Seeing the amounts of debris and particularly the fine fragments of broken up plastic on some Welsh beaches facing the SW wind or where the tidal surges have swept debris up inlets, one is reminded of the poetic musings of the Walrus and the Carpenter, as they walked along a beach before over-exploiting the local stock of oysters. Verses 4 & 5 of the poem as told to Alice in Lewis Carroll’s Through the Looking Glass were as follows:-
The Walrus and the Carpenter
Were walking close at hand
They wept like anything to see
Such quantities of sand:
‘If this were only cleared away,’
They said, ‘it would be grand?
‘If seven maids with seven mops
Swept it for half a year,
Do you suppose’ the Walrus said,
‘That they could get it clear?’
‘I doubt it' said the Carpenter,
And shed a bitter tear.
One consequence of the prolonged sequence of depressions swept across the Atlantic by the jet stream may have been a reduction in the “standing stock” of litter actually washing to and fro out at sea with more of it landing up on the shore. Back of envelope calculations would suggest that 40 days or so, with winds as they have been, might have swept ashore most of the litter from about 700 – 1000 nautical miles out in the ocean. Looking at the organisms growing on the litter, it was noticeable that while the lost whelk pots and other items thrown up from the near-shore seabed by the early storms had the usual range of barnacles and saddle oysters on them, the floating litter coming up then had few attached organisms. Debris floating in the open ocean for long enough usually gets colonised by things like stalked or goose barnacles (Lepas spp.). The occurrence of such organisms can give clues as to whether a proportion of the litter has come from out in the open ocean or from more local sources in and around the Irish Sea. It was interesting to see that photographs showed Lepas on the bottom of the boat on which the Mexican fisherman apparently survived, drifting across the Pacific for many months.
Lepas anatifera |
Lepas pectinata, which can be distinguished by the obvious radial ribbing on the shell plates |
Labels:
goose barnacle,
Ivor Rees,
Keep Wales Tidy,
Marine conservation,
marine litter,
marine pollution,
MCS,
rubbish at sea
Sunday, 2 February 2014
Winter Storms
Derailment on The Cob |
It's amazing, the power of nature. In my student days I lived on the prom at Aberystwyth, the top floor flat above the Chinese, opposite the pier. It was a great vantage point for sunsets and storms but well away from the danger zone; our only water hazard was the condensation streaming down the walls of the paraffin heated rooms.
Buckled lines north of Barmouth. Parts of the track were moved 9 feet towards the land. |
The wrong end of the Aberystwyth prom. |
Avian Pox
First it was
just a single Great Tit with an ugly brown growth on its head, then there was
another with a growth on its leg and another.
Great Tit with Avian Pox Birds are normally photographed for their beauty |
Avian Pox is a disease spreading
northwards and the hope is that the birds will develop an immunity to it; it
does not seem to harm them. It is also present in Dunnocks but harder to detect
against their brown plumage as they scuttle around beneath bird feeders.
If you see
birds with such growths it would be good if you could report the fact on the
new website promoting Garden Wildlife Health
It would be wise to give
your bird feeding station a thorough clean to reduce the likelihood of the
disease being passed on.
In February 2013 I think
there were three infected birds regularly visiting my feeders but this year I
have seen none. Did they recover?
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