Pembrokeshire, Wales
Finally got down to logging the glorious Raffles Girls' School Science trip to Wales 2013 here. This log is slightly back-dated because I had to copy and compile everything from my journal, worksheets and camera here. I think the idea of a field journal is one of the best in the world and I wish I weren't too lazy to put all the cool detailed facts I learnt and the diagrams and drawings I made here as well.
f/8, 1/250 s, ISO 250, 55-200@200 mm, Nikon D5000
Wales is truly one of the best most beautiful and pleasant places on Earth and one of the best, if not the best, memories of my life. But I'm fifteen and I do hope that Earth will bring something more mind-blowing someday.
We boarded at Orielton House, a Georgian mansion run and kept by the Fields Studies Centre, a UK charity that runs ecology and geology courses. The course we were on was an Edexcel A2 Biology enrichment course, the UK equivalent of our A-levels. The UK's academic curricula is pretty far behind Singapore's, especially RGS', so we got to do their A-level stuff at Secondary 3 (US Grade 9 / UK Year 11). Yay!
3 June 2013
We alighted from the coach to a beautiful sunset by the downs (and the not-so-beautiful flares of this photo. Oops.)
Here's Orielton House (officially Orielton Fields Studies Centre). The typical interior British regal flourishes are not shown.
Our daily routine was:
0730 - A matron of sorts goes up the stairs ringing a huge handbell, waking the dead
0800 - Doors to the dining hall and to a wholesome full English breakfast opens. I wouldn't recommend eating that every day. The only reason I can still walk is because we had full-day hikes and fieldwork each day to burn it all up
0830 - We begin to make our lunch sandwiches to take with us on our hikes and fieldwork. The usual fare was tomatoes, lettuce and shredded cheddar (which would stink up your whole field pack and later the dormitory when you wash your lunchbox but who can say no to cheese?)
0900-1030 - Lessons in Stable Yard (FSC converted the stable yard of the old Georgian family into classrooms). My tutor was Joe; I think his full name was mentioned somewhere but I forgot. We mostly learnt about ecology and the statistical methods used in it. We did a bit of geology as far as it aided our ecological understanding. Over the week we learnt about ecological succession, intertidal zones / rocky shore ecosystems and the 'period of emersion' and other cool bits of information like how dog whelks devour limpets (it's a gruesome story; read on to find out). We also learnt sampling methods and statistical methods like Lincoln Index, Student's t-test, the 𝑿² test (for asssociation), Spearman's rank, the Simpson-Yule species diversity index and kite diagrams to help quantify our findings in the field.
1030-1800 - Field work and wholesome long hikes complete with sampling equipment!
1800 - The best traditional British three-course dinners I have ever tasted. The sticky toffee pudding on one of the evenings was unmatched
1800-2100 - More lessons. This was usually compiling our fieldwork results and evaluating their link to theory
2200 - Lights out
On the same evening we arrived, immediately after our briefings and room allocations, we trapped some beetles and moths in the woods outside our classrooms. We also laid some mammal traps on grassy field beyond the football pitch. We laid out a really long tape measure along one edge of the field and another at a right angle to it. Then, using the markings as coordinates, we laid the traps according to the last few digits of our phone numbers. We later learnt that this was a form of random sampling.
4 June 2013
The next morning we collected the trapped critters. Here's a beetle in my trap:
Unfortunately we did not find anything in our mammal traps. We laid the traps again in a different area - now we did get one small mammal out of these when we collected them the next evening. Read on to see it!
Then we headed out to Cresswell Quay and Dale. I did not bring my camera with me because it would get soaked, so here are some phone photos.
Cresswell Quay:
We got into the waterproofs and wellies rented out by FSC:
Then we marked and released some crabs. We fished (crabbed?) them, painted them red and threw them back into the sea. Later we collected them and tried to do the Lincoln index on them but it didn't work out very well because we had only waited 2h (due to time constraints). We would have to wait weeks for the Lincoln Index to be reliable. Joe explained how the Lincoln Index works in a really neat diagram but I'm too lazy to draw it here.
At the end of this jetty was where we did the crabbing:
Then we headed out on a skiff to do some plankton sampling. We tied a weighted funnel-shaped sieve connected at the small end to a plastic bottle, then we zoomed around in the skiff. Plankton would supposedly then be caught in the bottle. The life jackets we had to wear made me feel like a commando. Here's us:
And here's the sea:
And here's the sea:
We got a dismal amount of plankton. Instead we caught a ctenophore! These things aren't exactly rare but it's very uncommon that they get caught in brute-force filter trailing. This one was a sea gooseberry (Pleurobrachia) - the most common ctenophore. It looked like a water baby and at first I thought it was some kind of debris. The FSC tutor on our skiff said this was the first time she'd seen one get caught in plankton sampling in years:
After completing the second stage of the crabbing and conducting the failed Lincoln Index, we did a short hike to Dale in wellies. Wellies were really irritating to walk in at first but you get used to it after a while.
And a crab copulating:
And then it was time to head back.
5 June 2013
The next morning we headed out Freshwater West and the sand dunes behind it (Broomhill Burrows). This was where Dobby's death was filmed in Harry Potter and the Deathly Hallows. We were told that the building of Shell Cottage for that scene considerably damaged the dunes' health and the surrounding plant ecology. It did look like it recovered, though.
Freshwater West:
f/9, 1/320 s, ISO 200, 18-55@18 mm, Nikon D5000
The Broomhill Burrows sand dunes are the perfect place to learn about succession because the sand nearest to shore (embryo dunes and foredunes) are at the earliest stages of it while the dunes furthest away (fixed dunes) are at the latest, so the progress of it can be seen clearly and easily. The slow differences in grass length and plant diversity were very apparent. We verified this with stratified sampling of the leaf length of ribwort at the different dunes using tape measure as axes (plural of axis, not the tool). The plants here are really tough - some species such as the sea bindweed have latex in their stems to protect against the ocean's salinity.
f/11, 1/125 s, ISO 160, 18-55@18 mm, Nikon D5000
These surfers have the whole ocean to themselves:
f/11, 1/200 s, ISO 160, 55-200@200 mm, Nikon D5000
Then we headed over the foredunes to the semi-fixed and fixed dunes behind. At each area we recorded the temperature, humidity, light intensity, wind speed and soil compaction to help us understand the environment affecting the diversity of plants growing there. It wasn't just the stability of the sand held by vegetation (or succession) that affected species diversity but also how exposed the dunes were to wind, salt spray and obstructions - the foredunes were right down to the strandline while the fixed dunes were sheltered from wind and salt by the dunes in front.
f/11, 1/200 s, ISO 160, 55-200@55 mm, Nikon D5000
This was the view from one of the sites where we sampled species diversity. When we got back to Orielton, we applied the Yule diversity index to our results.
f/10, 1/200 s, ISO 160, 18-55@45 mm, Nikon D5000
When we got back we also did a t-test on our measurements of ribwort plantain leaf lengths. Despite having some of the most advanced sampling and experimental equipment, Orielton's classrooms only had two IBM box desktops for computers (or they were hiding the rest from us) and no graphing calculators, so we did all our statistics by hand beyond the scientific calculator functions of +−×÷, squares, etc. It wasn't that tedious after we found out that our humble Casio exam calculators had a standard deviation function (albeit for only one data point at a time) hidden deep inside but still tedious enough to help us get a deeper understanding of how these statistical methods work!
6 June 2013
Thursday - it seems that every time I grow attached to a place it is almost time to leave.
We had a hearty breakfast to prepare for our longest day of the week hiking from Stackpole Quay to Bosherston along the beautiful Pembrokeshire coast, taking detours along the way to carry out some fieldwork (around 15 km in total, if I remember the two digits correctly, according to Joe's GPS). Stackpole Quay is a manmade harbour and a honeypot site to draw tourists away from Barafundle Bay which has been increasingly damaged by rising tourist numbers, despite its remoteness. You'll see why later.
The Atlantic ocean slowly came into view and earshot as we trudged from the designated car park to Stackpole Quay:
f/10, 1/200 s, ISO 160, 18-55@18 mm, Nikon D5000
Then we did some fossil hunting! We flipped over a rock and found this:
Along the way we saw quite a few of these fenced squares. They're tall and fine enough to keep out rabbits but not seeds, spores, insects and birds, so they help ecologists see what this area would be like without rabbits and and how it was like before rabbits were introduced to the area (they're not native to this coastal habitat). These fenced areas make it clear that the rabbits play a very important role in keeping the grass short and preventing dense vegetation from taking over (succession!). This helps to maintain some native populations such as weaker and smaller flower species by allowing them to take root and proliferate with less competition. Interestingly, by doing this, rabbits also make life easier for the native birds of prey, such as buzzards, who include rabbits in their menu! This keeps the numbers of these introduced rabbits down such that they do more good than harm to the native biodiversity. In Skomer Island, which we visited on the last day, the rabbits' lawn-mowing creates nesting areas for puffins who nest in underground burrows. I've put up pictures of these which you'll see later.
I also wonder if these rabbits are one of the reasons for the difference between Britain's coast and other coasts at the same lattitude. USA's east coast, for example, tends to be backed by dense vegetation of diverse plant species and its Pacific coast by temperate rainforests. Someone enlighten me please?
Along the way we saw a relic blowhole. I have no pictures of it because I had my telephoto on and for some reason I didn't get my phone out. We learnt about blowholes in Geography this year and it was really grand to see dreaded exam material come to life before our eyes, with the roaring sea in our ears!
Then we arrived at Barafundle Bay. This beautiful bay has been voted among the world's best beaches for years. Tourists swarm here in the peak of summer, increasing the weathering here so the National Trust tries to draw them away to other honeypot sites instead. When we visited, the beach and ocean were empty. The Welsh coast is rich in geological landforms - in this bay alone there are two caves on their way to being arches, wave-cut platforms, fault-guided steps and sand dunes at the back. Headlands and bays themselves tell a good story. They form because they're made of different stuff - clay gets eroded faster than limestone and sandstone (the main kinds of rock in Pembrokeshire). Over time the waves striking the clay, which has retreated much more than the limestone and sandstone, becomes gentler and start to deposit instead of erode because they get broken by the headlands first. The headlands also guide the waves such that they strike the bay at an angle that weakens them even more. This creates Barafundle's white sandy beach:
f/10, 1/125 s, ISO 160, 18-55@18 mm, Nikon D5000
Yeah, take Geography! It's good for you.
f/10, 1/250 s, ISO 160, 18-55@55 mm, Nikon D5000
Joe also told us what makes the roaring sound of crashing waves. When a single droplet of water breaks the water surface, forcing the surface to bend, accomodate the droplet and eventually merge with it, it makes a small sound. When a wave breaks along a shoreline, this happens on a scale millions of times larger at the same instant, combining each of these millions of small sounds.
f/10, 1/250 s, ISO 160, 18-55@18 mm, Nikon D5000
And here's a chuffed chough:
f/10, 1/200 s, ISO 160, 18-55@18 mm, Nikon D5000
Then we made a stop somewhere here along the trail to do a transect sampling of ribwort width of varying distances from the foopath. The tutors were very surprised that we knew how to use venier calipers, exclaiming that we were the first group they've met with this exotic knowledge. When we got back, we put our measurements through the Spearman rank.
Then we saw a swallow hole, carved by water striking porous rock:
And a collapsing blowhole:
And then we came to Stackpole Head:
f/8, 1/250 s, ISO 160, 18-55@18 mm, Nikon D5000
Not sure if you can see it but this was as far as my kit lens could go. In that upper cave is a guillemot's nest. The variety in Pembrokeshire's landforms makes it an important place for all kinds of nesting birds:
A little later we reached Broad Haven bay. I stupidly had my telephoto on so I couldn't get the whole beach into the picture. Look at the wave-cut platform:
f/10, 1/160 s, ISO 160, 55-200@55 mm, Nikon D5000
Here's a stack with caves in it:
Here's the beach:
f/13, 1/250 s, ISO 160, 18-55@55 mm, Nikon D5000
As we walked on, I saw something spectacular. It's not the humans swimming in this pond:
But the fish! This pond is so far from the strandline; I'm pretty sure its a rainwater pond. How did the fish even get there!? There are no streams around so maybe this was connected to the sea at some point but the sea is unbelievably far away. There's also nothing else in this clear pond (besides humans) so what are the fish eating? It could also be that some clown put them there but I doubt the Welsh are one of those types. Still a mystery:
Then we arrived at our final stop, the Bosherston Lily Ponds. These man-made lakes were built between 1760-1840 as part of the Stackpole Estate. They support a rich biodiversity because the stagnant waters allow nutrients to sink to the bottom, supporting the growth of all kinds of water plants which support animal life:
f/11, 1/160 s, ISO 160, 18-55@18 mm, Nikon D5000
That was the best 15 km of my life. We headed home to Orielton and devoured dinner. Then I took a walk in the grounds outside the house:
f/5.6, 1/100 s, ISO 250, 55-200@200 mm, Nikon D5000
f/5.6, 1/200 s, ISO 200, 55-200@200 mm, Nikon D5000
And then I played football with my dorm mates before the evening lessons:
In the classrooms we learnt about rocky shore ecology to prepare us for the next day which would be spent at a rocky shore, so I'll save these weird and wonderful rocky shore things for the next section.
The next morning was rocky shore day. We were supposed to go to Sawdern Point but the tutors were in a great mood and decided to take us to Freshwater East instead because it's prettier although farther:
f/8, 1/250 s, ISO 200, 18-55@18 mm, Nikon D5000
Here's how perfectly rocky it was. This shore transcribed the intertidal diagram we learnt the previous evening into reality, all the way from the subtidal zone to the splash zone. The subtidal zone receives the least light which makes it a very delicate area. Some organisms are here because they can't function out of water but can't go too low either because they need light. For instance, seaweed can't photosynthesise outside water but need enough light to do it. This causes a lot of competition for a limited area. The middle shore is the most rugged, it takes lots of wave action and varies in temperature throughout the day. The splash zone is a sensitive habitat as well; the organisms there are always in danger of dessication and it's hard for them reproduce and disperse their seeds or spores. The rocky shore is a unique ecosystem this way; each zone has a specific selection of life:
To support this we set out to do some sampling to test for association between the abundance of three different species of topshells (Gibbula cineraria, G. umbilicalis and Osilinus lineatus) and the elevation up the shore. But first we collected specimens to get a general idea of what's there. Here's a greenshore crab and a dog whelk. Greenshore crabs eat almost anything and dog whelks use enzymes to digest a limpet's stomach before sucking the resulting juice out. It's brutal out there:
For our topshell sampling, we used cross staffs to mark out sampling points at 0.6 m intervals in height and sampled the species abundance with quadrats on the ESACFOR scale. This was a systematic interrupted sampling because we didn't have time to do a belt transect. Back in Orielton, we did the X² test for assocation. Most people including got a 'reject null hypothesis' result which means even species so similar in niche are picky about their rocky shore spots, showing just how delicate this ecosystem is. Here's the view from a sampling point:
Here's a limpet surrounded by barnacles. Limpets change their sex somewhere in their lives. Their class name is Gastropoda which means stomach foot because that's what they are - a walking stomach. Usually, or at least for the limpets here, each limpet has a favourite spot called a home scar and it grows into a special shape that fits that spot. When the tide comes, the limpet wanders off. When the tide's back, it sucks itself back onto the home scar. As for the barnacle, it finds a rock (or limpet) it likes and headbuts the rock until its gluey legs stick out of its head which sticks the barnacle to the rock. Then it stays there for the rest of its life. It's also a filter feeder:
Here's a limpet surrounded by barnacles. Limpets change their sex somewhere in their lives. Their class name is Gastropoda which means stomach foot because that's what they are - a walking stomach. Usually, or at least for the limpets here, each limpet has a favourite spot called a home scar and it grows into a special shape that fits that spot. When the tide comes, the limpet wanders off. When the tide's back, it sucks itself back onto the home scar. As for the barnacle, it finds a rock (or limpet) it likes and headbuts the rock until its gluey legs stick out of its head which sticks the barnacle to the rock. Then it stays there for the rest of its life. It's also a filter feeder:
f/5.6, 1/200 s, ISO 200, 18-55@48 mm, Nikon D5000
The view at lunch:
f/10, 1/200 s, ISO 200, 18-55@55 mm, Nikon D5000
f/10, 1/200 s, ISO 200, 18-55@40 mm, Nikon D5000
Here is me being grateful for wellies:
Here's a kittiwake that kept us entertained while we chewed on shredded cheddar:
f/11, 1/400 s, ISO 200, 18-55@55 mm, Nikon D5000
And that was about it for a lovely Friday outside. When we headed back we did a bit more research into our the rocky shore species our group was assigned last evening (limpets) and gave the class a presentation! Then we did some preliminary research on our individual investigation project (we were briefed on this at the start of the trip) of which the sampling would be done tomorrow. Mine was 'Is there a correlation between the number of Nucella lapillus (dog whelks) and the number of dead barnacles at West Angle Bay?' As we didn't have computers, we did our research the prehistoric way of flipping through Orielton's abundance of books and journals. Dog whelks eat barnacles but this project was interesting because it's about dead barnacles. This means a negative result would be possible because it could be that barnacles keep away from dog whelk territory in the first place and if they're not there, they can't die there. Moreover dog whelks lead very sedentary lives so they're unlikely to make a lot of effort chasing the barnacles that avoided them. While I was reading up on this, I found a story of a scientist who marked and released dog whelks, then waited a year to collect them to do a Lincoln Index. It didn't work because he found most of the same dog whelks. Another not-so-fun fact I read about dog whelks was that their proliferation in Wales is an indicator of rising sea levels because they were from and are adapted to warmer climates (not sure if introduced or washed over somehow), settled in Wales and have been doing well.
Barnacles were much more complicated; I never knew something so small and abundant could be so complex until I did these readings on them. The factors affecting where they choose to live outnumbered my fingers and overlapped one another; the adversities they could survive were much more. No wonder Darwin managed to write an exhaustive tome on barnacles, after which he remarked, 'I hate a Barnacle as no man ever did before, not even a Sailor in a slow-sailing ship.'
8 June 2013
Here's me doing my sampling:
And here are my friends at theirs:
We completed our samplings in two to three hours, making it before the tide came in. The tutors were surprised and said they'd never seen a group as fast as ours. Here's the view at lunch:
Another alfresco view:
When we got back to Orielton, I put my measurements through the Spearman rank and got a 'reject H₀' result, suggesting the presence of dog whelks isn't a major consideration for West Angle Bay barnacles choosing a home! That's cool.
And because we had nothing better to do, we checked out a stinging nettle leaf that someone carefully plucked from the field. Coming from Singapore, this widespread nettle here is a novelty to us. For some reason I thought its stings grow out from the edges and had no idea they were all over the surface. So I held it between my thumb and forefinger and got duly stung. Well, Mr Evans (our biology teacher) did say you must do it at least once before you die:
Here's a dock leaf. It's supposed to soothe nettles' stings but it didn't work for me. I'm not sure if it's scientifically supported that they help or if it's just an anecdotally supported belief. Anyway, if the dock leaf does produce something that messes up the nettles' stings, I wonder why they still like to grow together? That would be an interesting ecological relantionship. I brought both of these leaves back to Singapore and laminated them into a bookmark:
9 June 2013
This might be just be the saddest Sunday of my life. All the field work and presentations of the week were over and the tutors took us to Skomer Island for a sampling equipment-free full day out! The absence of quadrats and cross-staffs in my hand actually made me rather sad. It was a constant reminder that this was the last day.
We spent the whole day going all around the island, looking hungrily (spiritually) at Atlantic wildlife with wistful tropical eyes. Here's a foxglove! They're really cool because they can either save you from a heart attack or kill you by a heart attack:
And here we are ready to board the skiff to Skomer:
f/8, 1/160 s, ISO 200, 18-55@18 mm, Nikon D5000
And here are some kayakers getting into their racing kayaks. Not a bad way to get around in Wales:
f/10, 1/125 s, ISO 200, 18-55@46 mm, Nikon D5000
Here's the view from our skiff! This is water you will never find in Singapore:
As we arrived we watched some puffins try to fly while listening to Joe's commentary, 'It's trying to take off! It can't! It's too fat!'
We saw a rabbit which reminded me of Watership Down:
f/9, 1/80 s, ISO 320, 55-200@200 mm, Nikon D5000
f/11, 1/320 s, ISO 200, 55-200@190 mm, Nikon D5000
Then we saw some seals! They were really far below, so this is a badly cropped photo. Kipling must have had this scene in mind when he wrote the Seal Lullaby:
f/10, 1/125 s, ISO 200, 55-200@200 mm, Nikon D5000
Here's one having a swim:
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And wild flowers were blooming everywhere, thanks to the rabbits! We were told the name of each wild flower species but I've forgotten most. It's all right, though, because names are not important:
f/9, 1/160 s, ISO 250, 55-200@200 mm, Nikon D5000
Then we had a glorious alfresco sea view lunch:
While I savoured my sandwich, I managed to pan a kittiwake:
f/10, 1/400 s, ISO 250, 55-200@200 mm, Nikon D5000
After we got going we bumped into a dead rabbit. Joe said a buzzard probably took it. Sure enough, as I looked up into the sky, a considerable number of buzzards were circling the island. They seemed to be the most common bird of prey here. I wonder why the buzzard didn't eat it, though. I also wonder if there's anything that eats buzzards to keep their numbers down. I expect most of the predation on buzzards happen when they're chicks and when they're grown it's hunger and fights that bring them down.
Then we arrived at a cliff with puffins in every corner. It's the nesting season; they're all out with nesting material in their mouths and were climbing in and out of their burrows:
f/10, 1/400 s, ISO 250, 55-200@200 mm, Nikon D5000
Here's a puffin being cute:
Here's one trying to make its home a bit warmer:
f/8, 1/250 s, ISO 250, 55-200@200 mm, Nikon D5000
And here's another:
f/8, 1/250 s, ISO 250, 55-200@200 mm, Nikon D5000
Here's one taking off:
f/8, 1/250 s, ISO 250, 55-200@200 mm, Nikon D5000
Here's one in the burrow!
And here are two gulls:
And two razorbills:
f/9, 1/125 s, ISO 250, 55-200@200 mm, Nikon D5000
Overlooking a jellyfish:
Just to show how large the jellyfish was:
And then it was time to leave...
On our last evening I took a picture of this board in the games room of all the places we've been to. Because this was also where we packed our lunches, the room was named Ein Gedi after an oasis, just like Wales:
Nobody wanted to leave:
As the beautiful sunset and the last evening class drew to a close, Tan Fong Han, my senior in the year above, wrote and read out a farewell poem:
Orielton
I will miss this shoreline, thisForaging around in foreign fields
on cliffs that overlook the vast
brimming sea, this is where
we learnt that cobblestones are
pathways leading out to open waters
with quaking herring gulls and
slow tenacious dog whelks.
(...)the sun blazes for long hours. at times, it is merciless.
but the sun is
not infallible
as the day ages, it
weans, gradually learning that
embracing this world of guillemots and
wave-beaten shores is a reprieve
to its spiteful struggle.
i place my hands in the swirling rockpools;
the topshells hover like stars in
the dark night sky; the soft slushing of the water as
they gludder around beckons that
somewhere up there
two stars are timidly moving and
gradually colliding,
where our hearts are quietly fluttering like the
trepid uncertainty of the night and our fists
no longer ball up in tightly-clenched burden.
the streams fill up and overflow with due abundance.
I've learnt so much from this trip in such a short time, both academically and in other ways, most of which would not have been possible in Singapore. Wales and Pembrokeshire will always make a special ring in my heart. Thank you to RGS and the FSC for giving me the best experience of my life and showing me beauty. The past week has popped lots of questions about ecology and evolutionary biology into my mind and I can't wait to answer them in university. In the meantime, I'll keep seeking the ocean paths.
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