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‘The Big Garden Birdwatch’

Penny Tomkins, 23 Ionawr 2015

Helo Gyfeillion y Gwanwyn,

Mae yna arolwg gwyddonol cyffrous yn digwydd y penwythnos hwn, ac mae angen eich help chi! ‘The Big Garden Birdwatch’ yw’r enw a’r RSPB - elusen sy’n helpu i edrych ar ôl ein bywyd gwyllt - sy’n trefnu. Gallwch chithau helpu drwy gofrestru ar-lein yma: https://www.rspb.org.uk/birdwatch/. Wedi gwneud hynny, treuliwch awr dros y penwythnos hwn yn cofnodi’r adar sy’n dod i’ch gardd neu lecyn gwyrdd yn agos i’ch cartref. Bydd y pecyn gwybodaeth ar wefan RSPB yn eich helpu i adnabod yr adar! Wedyn, rhowch eich canlyniadau ar wefan RSPB fel eu bod nhw yn gallu eu hychwanegu at yr arolwg mawr cenedlaethol ar boblogaethau adar, sy’n ceisio darganfod mwy am hynt a helynt ein ffrindiau pluog!

Mae’r ‘Big Garden Birdwatch’ wedi bod yn mynd ers 1979! Gallwch ddod o hyd i ganlyniadau blaenorol yma: https://www.rspb.org.uk/birdwatch/previous-results/. Mae arolwg blynyddol a chenedlaethol yn ffordd wych o sylwi ar newidiadau mewn poblogaethau adar. Mae hyn yn bwysig, oherwydd pan fyddwn yn gwybod pa adar sy’n mynd yn brin, gallwn ddod i ddeall pam mae hyn yn digwydd a cheisio helpu’r adar i oroesi. Mae’r ddrudwen yn enghraifft o hyn. Ers i’r ‘Big Garden Birdwatch’ ddechrau yn 1979, mae poblogaeth y ddrudwen wedi lleihau 80%. Mae’r RSPB wedi bod yn codi ymwybyddiaeth o’r pethau y gallwn ni wneud i helpu’r adar hyn, fel torri’r lawnt mewn rhannau o’r ardd er mwyn i’r ddrudwen allu cyrraedd eu bwyd, sef trychfilod a phryfed bach sy’n byw yn y pridd.

Drudwy yn y Gaeaf (llun drwy garedigrwydd wefan yr RSPB).

Dyma rai syniadau ar sut i ddenu adar i’r ardd: http://www.rspb.org.uk/news/387868-top-10-bird-feeding-tips-this-winter. A dyma weithgareddau difyr yn ymwneud ag adar: https://www.rspb.org.uk/birdwatch/family-fun/.

Bydd Sain Ffagan Amgueddfa Werin Cymru ac Amgueddfa Genedlaethol Caerdydd yn cynnal gweithgareddau ‘Big Garden Birdwatch’ y penwythnos hwn! Os ydych chi eisiau ymuno, mae mwy o fanylion yma:

Caerdydd           Sain Ffagan

Diolch yn fawr i bawb wnaeth yrru data tywydd ata i yr wythnos ddiwethaf. Rwy’n edrych ymlaen i weld os yw hi wedi bod yn gynhesach neu’n oerach yr wythnos hon ac os yw hi wedi bwrw eira neu gesair! Cofiwch, os wnewch chi yrru’ch data a gadael i mi wybod ar-lein pan fydd eich planhigion wedi blodeuo, byddwch yn derbyn gwobr Gwyddonydd Gwych a bydd cyfle i chi ennill Taith Natur!
 
Daliwch ati Gyfeillion y Gwanwyn!

Athro’r Ardd

Drudwy (llun o wefan RSPB)

Foul Bay

Teresa Darbyshire, 21 Ionawr 2015

20.01.15

Well, Foul Bay did live up to its name on what actually turned out to be the best weather we’ve had so far. All of my sampling sites are generally chosen for having easy access off the road, but I had taken a risk this time and picked a site where the road ended before the coast, leaving what I thought would be a reasonably distanced walk. However, as the road finished close to a settlement we stopped in for a quick chat and some advice about access to the shore. The advice was that our chosen route would be unsuitable but there was another track that would get us close a little way back down the road, it was a ‘little soft’ but our 4x4 ‘should’ be fine!

We found the track and made it to the first wire gate (a particular type of access gate here that involves removing part of the fence and then driving through and replacing it). Underneath the wire gate was a very soft, deep-looking area of water (see photo), which with the peaty ground here normally signifies something to be avoided! Looking onwards, the supposedly clear track almost instantly disappeared (to our inexperienced eyes) and therefore we debated the wisdom of continuing. The alternative was to walk to the shore, which appeared to be around 2-3 miles away! As we were on our own and the people from the settlement had driven away, we knew there was no help should problems arise (i.e. getting irretrievably ‘bogged’). We eventually made the difficult decision that this one would have to be cancelled. This left us with a rather disconsolate two hour drive back empty-handed, one to put down to experience unfortunately. A foul day indeed!

Tomorrow we are flying to Bleaker Island, to the southeast of the islands, which fills in a large gap in my coverage around the islands. Fingers crossed that we can find a variety of shores here to cover and improve our record!

Digging for worms in the Falkland Islands

Teresa Darbyshire, 20 Ionawr 2015

18.01.2015

First of all, here is the photo of the reproductive stage of a worm (photo 1), which I found during night sampling two days ago, but forgot to send! Very nice to collect, just unfortunately not what I was after.

Mare Harbour was an interesting visit, having never been down to a shore almost completely surrounded by barbed wire before (photo 2)! This shore is within the military area here so I was lucky to get access at all, although the officer on duty seemed totally bemused as to why I would even want to. It turned out to be a very hard and rocky area with some areas of flat rocks over gravelly sand and other areas of vertically ridged rock. The flat rock areas had a reasonable diversity of species although collecting was hard work as there were only small numbers of animals to find. Still I did come away with some animals I definitely haven’t seen before including the ‘pretty’ catch of the day, which was a syllid (see photo 3) with its wonderfully intricate hair-do. There were also many flabelligerids (as difficult to say as spell: photo 4). This particular strange species covers itself with mucus, which silt adheres to. This gives it the appearance of jelly when you find it.

Brendan also managed to get out on a dive today which he was very pleased about although his description of it being ‘just like West Wales’ led me to believe it wasn’t the best that the Falkland Islands can offer. However, he brought me back a present of 4 bags of mud. Not the most romantic present I’ve ever been offered certainly, but still there were some nice worms in there including a bamboo worm (maldanid: photo 5). These worms are often very hard to collect whole making identification almost impossible, however, this one was completely intact.

19.01.15

Today saw us driving up to the north east of the island to the region of Rincon Grande. As usual I had no idea what to expect, but with the wind howling again I merely hoped the rain would hold off, so that the couple of hours on an exposed beach would not be too gruelling. I got my wish for most of the duration, to ask for more would just be greedy I suppose!

The shore was mostly rocky again but with one small inlet of softer muddy sand. I set Brendan to work with the fork (photo  6) and studiously watched what came up – lots of tubes and other worms dangling down! We spent some happy time here slowly teasing the long worms out of their sand beds and shoving other tubes into pots before moving on.

Further round the bay in the rockier sections we moved on to rock turning, gaining a small diversity of worms which again were small in number and difficult to find. Working independently with forceps and pot in hand (photo 7), Brendan managed a larger haul than me, which he was very proud of although apparently we were not competing!

On our last stop we returned to our starting point in the softer sediment but at the low tide mark this time to see if the type of worms had changed. There were certainly a couple of different types and we also found an unusual type of crustacean, a serolid isopod, which is flattened and ‘trilobite-like’ and often found in pairs (photo 8). These certainly were an intriguing distraction. Shortly afterwards the tide turned and we were out of time, which meant we had to head back.

Off to the northwest tomorrow to Foul Bay – hopefully not as bad as the name sounds!

Falkland Islands Marine Bristleworms

Teresa Darbyshire, 19 Ionawr 2015

The Polychaetes of the Falkland Islands project has been running since 2011 with two highly successful field trips run so far. The project has been well supported with two Shackleton Scholarship Fund grants and support form the local environmental groups and institutes. So far, over 30 families of polychaetes have been identified from the samples and 2 new species have been described, with more on the way. The third field trip hopes to build on the success of the previous two, expanding the range of sampling sites and seeking new opportunities for collaborative project funding in the islands.


16.01.2015

After the usual gruelling 18 hour flight, I’m back out in the Falkland Islands again to continue expanding my range of sampling sites, maintain my contact with those out here and also investigate further project funding opportunities. This time my husband has travelled out with me to see what all the fuss is about and also to try and understand what it is I actually do (you can see his eyes glaze over when I try and explain things so maybe seeing first-hand will actually help!). He’s going to come out with me in the field, help me collect and generally be an extra person in those remote areas I end up in. I’m not sure he knows what he’s let himself in for but at least he may stop referring to my fieldwork as ‘rock pooling for adults’!

The weather hasn’t been kind to us initially, being very wet and windy, even beyond normal Falkland Islands standards! It is supposed to be summer here but it was only 5°C when we landed, cooler than the UK when we left, and the horizontal hail driven into us at hyper speed by the winds was no fun at all!

This was my first full day here and after finalizing all of the arrangements for the next two weeks, our first sampling was a short but harsh introduction to the kind of work I sometimes find myself doing. This was night sampling, attempting to collect the reproductive forms of certain polychaetes that come out at night, swimming free in the water to spawn and are attracted to bright lights. For this reason we found ourselves in a Stanley marina, on a pontoon at 11pm, in the rain, dangling an underwater torch into the water and sweeping a fine mesh net around it, collecting the many different small creatures that were attracted to it (see photo). It was too late to have a detailed look at our catch, so they went into the fridge to keep cool overnight until I could get to the lab for a look and I went to bed.


17.01.2015

The order of the day today was to have a look at what I had managed to catch in the marina last night. Most of what I had were small Crustacea and the smallest jellyfish I’ve ever seen (about 2mm wide) but there were 4 worms of the right kind of appearance, albeit a bit smaller than I would have expected (about 10 mm long). I’ve been allowed access to the Fisheries lab while I’m here and their camera microscope so I was able to take some photos of the little critters. Interesting as they were, unfortunately they were not what I was after, which was a bit disappointing. They were certainly reproductive stages of polychaetes but of a different group to the one I am after, although I haven’t determined which group yet. Still, better than nothing!

The weather has been better, being mostly dry, a bit warmer and marginally less windy. Fingers crossed for tomorrow’s weather, which is the first shore visit. It is an early start though, with a 6.30 am wake-up call, to get to Mare Harbour, about an hour and a half drive away. Hopefully something interesting will turn up!

Bwrw eira a dyfnder eira

Penny Tomkins, 16 Ionawr 2015

Shwmae Gyfeillion y Gwanwyn, 

Diolch am anfon cofnodion yr wythnos ddiwethaf. Mae hi’n bendant yn dechrau oeri, ac mae rhai ohonoch chi wedi gweld eira hyd yn oed! Dyma pam dwi am esbonio sut mae meteorolegwyr (gwyddonwyr tywydd) yn mesur eira. 

Mae mesur faint o law sy’n disgyn yn hawdd o’i gymharu â mesur faint o eira sy’n disgyn. Fydd eira ddim yn bihafio! Bydd yn aml yn cael ei chwythu gan y gwynt ac yn lluwchio, sy’n golygu bod yr eira’n ddwfn mewn mannau ond yn llawer llai dafliad carreg i ffwrdd. Oherwydd bod yr eira’n disgyn yn anghyson, bydd y mesuriadau o’r llefydd yma’n anghywir! Dyna pam mae’n rhaid mesur mewn mannau gwastad, agored ymhell o ble fydd eira’n lluwchio. Bydd eira hefyd yn chwarae gemau gyda’r Meteorolegwyr sy’n ceisio ei fesur – bydd yn toddi’n ddŵr, cyn rhewi fel iâ. Felly dyw’r eira sy’n cael ei fesur ddim bob tro yn cyfateb i faint o eira sydd wedi disgyn. Mae eira newydd yn disgyn ar ben hen eira hefyd, ac mae’n anodd dweud faint o eira sydd wedi disgyn o un diwrnod i’r llall. 

Mae’n rhaid i’r meteorolegwyr gofio holl driciau’r eira a meddwl am ffyrdd i ddarganfod faint o eira sydd wedi disgyn. Byddan nhw’n edrych ar gwymp eira (faint o eira sy’n disgyn mewn diwrnod) a dyfnder eira (cyfanswm dyfnder yr eira, hen a newydd). Un ffordd o fesur cwymp eira yw gyda ffon bren. Bydd y meteorolegwr yn gosod y pren mewn lleoliad agored lle na fydd eira’n lluwchio ac yn mesur yr eira bob chwech awr. Drwy glirio’r eira o’r pren ar ôl ei fesur, dim ond eira’r diwrnod hwnnw fydd yn cael ei fesur, a gall y gwyddonydd ddweud faint o eira sydd wedi cwympo ar y diwrnod hwnnw. 

Gallwn ni hefyd fesur eira wedi toddi ar ffurf dŵr. Gallwch chi felly ddefnyddio’ch mesurydd glaw i fesur cwymp eira. Os taw dim ond ychydig o eira sy’n cwympo, bydd yn toddi yn y mesurydd beth bynnag, ond os yw hi’n bwrw’n drwm, ewch â’r mesurydd i mewn ac aros iddo doddi’n ddŵr. Gallwch chi wedyn fesur y dŵr fel rydych chi wedi’i wneud bob wythnos, a’i gofnodi fel glawiad yn eich cofnodion tywydd. 

Os oes eira ar lawr a bod digon o amser i arbrofi, beth am fynd ati i fesur dyfnder yr eira? Y cyfan sydd ei angen arnoch chi yw pren mesur (neu pren eira os ydych chi am siarad fel gwyddonydd gwych!). Gwthiwch y pren i’r eira tan ei fod yn cyffwrdd y ddaear a chofnodi pa mor ddwfn yw’r ddaear fesul milimedr. Rhaid i chi fesur o arwyneb gwastad (fel mainc) mewn lle agored lle nad yw’r eira’n lluwchio. Rhaid i chi gofnodi o leiaf tri mesuriad i gyfrifo dyfnder cyfartalog yr eira lleol. Cyfrifwch y cyfartaledd drwy adio’r cofnodion gwahanol a’u rhannu gyda’r nifer o gofnodion. Os ydw i’n cofnodi tri dyfnder o 7cm, 9cm a 6cm, rhaid i fi adio pob rhif (7 + 9 + 6 = 22) cyn rhannu gyda 3 (22 / 3 = 7.33). Dyfnder cyfartalog yr eira felly yw 7.33cm. 

Mae gorsafoedd tywydd fel y Swyddfa Dywydd (MET Office) wedi troi at dechnoleg i ddyfeisio dulliau newydd o fesur dyfnder eira. Edrychwch ar y llun o un o orsafoedd eira’r Swyddfa Dywydd. Mae nhw’n defnyddio synwyryddion laser i fesur dyfnder yr eira ar yr arwyneb gwastad. Gall meteorolegwyr gasglu data o bob cwr o’r wlad wrth wasgu botwm – llawer haws a mwy dibynadwy nag anfon pobl allan i’r oerfel gyda phren eira! Mae pob un o orsafoedd eira’r Swyddfa Dywydd i’w gweld ar y map – oes un yn agos atoch chi? 

Llun o Synhwyrydd Dyfnder Eira y Swyddfa Dywydd.

(Wefan y Swyddfa Dywydd)

Map o leoliadau Synwyryddion Dyfnder Eira y Swyddfa Dywydd – oes un yn agos atoch chi?

(Delwedd o wefan y Swyddfa Dywydd)

Os yw hi wedi bwrw eira, cofiwch fesur y cwymp gyda’r mesurydd glaw neu’r dyfnder gyda phren eira a nodi’r canlyniadau fel ‘Sylwadau’ wrth uwchlwytho eich cofnodion wythnosol. Bydd yn ddiddorol cymharu dyfnder yr eira â chwymp yr eira yn y mesurydd glaw! 

Daliwch ati Gyfeillion y Gwanwyn, 

Athro’r Ardd