Grappling with Aquatics

Yesterday I teamed up with fellow Skye naturalist Neil. Our plan was to hit some small lochans in the hills above Digg, situated in the shadow of the Trotternish Ridge. There are very few botanical records from each of the three monads we visited, though there is a fairly decent list of aquatic/marginal plants found during the NCC Freshwater Loch Surveys, dating from 1989. We visited NG4669, NG4668 and NG4569. Prior to our arrival these monads held records for a mere 37, 38 and 59 species. I can't say we added very much (moorland in winter is hardly a rewarding habitat to search) but we managed to identify 35, 33 and 28 species respectively, with the cumulative total being a mere 49 species. My spreadsheet for the day has just 96 rows, that's really poor considering it covers three different monads. I emailed it off to Stephen, BSBI Recorder for Skye, and I'm sure that once he's finished rolling around the floor in laughter, he'll let me know which species, if any, are new to the area. Later - Yellow Pimpernel, Lesser Clubmoss and the Sparganium (species not determined) were new to the area.

The view across a couple of lochans during yet another lovely day

I've been a bit lucky jamming two consecutive dry days. It was wet and cold for several days, then I took my two days off work and had good weather. Today it's right back to being wet and windy again and looks set to stay that way for at least a few more days. 

We soon discovered that the water levels were a bit higher than usual, fully submerged heather clumps being the obvious giveaway clue. But we had wellies, we felt bold, we waded straight in. 

This was our first clue that the water level was higher than usual...

Underfoot was a veritable carpet of Shoreweed, readily recognisable as starfish-shaped basal rosettes sitting amongst a network of stolons. The stolons root freely and give rise to yet more plants. In these images you can see the stolons spreading outwards from the parent plants.

Shoreweed Littorella uniflora exhibiting vegetative reproduction via stolons

A stolon is essentially a horizontal stem (or 'runner') with nodes. It runs above, or along, the surface rather than beneath the surface as would a rhizome. Each node can put down roots and produce a new plant. In the case of Shoreweed, this is how it spreads when submerged. When water levels drop the plant can happily survive on exposed mud and is then able to produce flowers and can sexually reproduce via cross-pollination. Otherwise it makes do with vegetative reproduction via stolons. It's a very common plant in shallow loch edges up here, clearly these dual tactics work. I've yet to see a Shoreweed in flower, if water levels fall this summer I shall have a close peer. 

I had my heavy-duty grapnel attached to about fifty feet of line. The very first cast saw me hooked up on rocks. As did the second and third. I decided to shorten my casts to maybe twenty feet rather than the full length of the line. I really didn't fancy going for a swim to retrieve my grapnel, wading up to my thighs wasn't much of a better option, but beats a swim. Luckily it never came to that and I managed to un-snag it each time by walking up and down the shore and tugging until it freed itself. It's going to happen one day though, and probably when there are lots of people watching, I just know it...

The next aquatic plant we found was Floating Bur-reed. This is another fairly common plant up here. The floating leaves betrayed its presence to us and eventually I found some close enough to the margin to take a few photos.

Floating Bur-reed Sparganium angustifolium as seen from the surface

My camera is submersible, as per the Shoreweed pics above, and I wondered what these leaves would look like taken from beneath the surface. It was a case of sticking my arm in, pointing the camera in the right drection and basically hoping for the best. I took a quick burst of images - the water was seriously cold - and hauled the camera up to see what I'd captured.

The best of a bad bunch, but I quite like it! 

I have no idea what the white 'orb' is in the centre of the image. Presumably not ghost or sasquatch related, whatever it is!

We had it in mind to check several small lochans, Neil's large scale map showed us where we needed to aim for, around the larger hills, down steep slopes, across boggy bits, but never wandering more than a mile or so from the car. We very quickly lost sight of the road as we crested small rises and descended valleys and, apart from two farm dogs that barked at our passing, we had the place entirely to ourselves. 

The second lochan was very shallow and rich with waterplants, both aquatic and marginal. First though, we were met with a strange sight. Lots of thick green stems washed up on the banks

I didn't know what these were, though they looked kinda familiar. I tried going through various aquatic plants in my mind, Common Clubrush has chunky stems, but they aren't ridged like these were. Plus these were very thick! Neil suddenly found one with what looked almost like a pondweed flower near the tip, which only added to my ever increasing confusion

Thankfully we soon found larger fragments and the penny slowly dropped - these were sections of horizontal stem, not vertical stems!

Rooting horizontal stem - as modelled by Neil

I slowly came to the conclusion that this was Bogbean Menyanthes trifoliata, which was later proven when we found a very shallow lochan in which it was possible to see the dead trifoliate leaves amongst the submerged stems. Phew, that was hard work, but at least I should recognise it next time! We still don't know why so much of it had broken off and washed up on the edges. Admittedly it's exposed terrain, but surely these lochans are too small for big waves to form? And yet the dumped stuff certainly did appear to be wave-deposited. I guess we have had strong winds lately. 

We found a lovely lochan, very shallow and very heavily vegetated. Lots of Brooklime and forget-me-not rosettes (all submerged, of course) and a mass of pondweed leaves. Ok, so I'll happily throw my hands up and confess straight away that I don't find pondweeds particulary easy to identify. I typically see Bog Pondweed in water less than a foot deep, often in roadside ditches or damp patches on moorland, and anything else is a novelty. Perfoliate Pondweed is easy, obviously. But the rest are a bit...'meh' So when I saw this lot all I could honestly say was, "that's not Bog Pondweed". 

I did collect a sample, but haven't come to any definitive decision yet. I'll keep at it. 

There was a fast-flowing deep channel running through the middle of this lochan, complete with swirling carpets of Callitriche (again, I have a sample but haven't come to an ID yet) and a small patch of Alternate Water-milfoil, growing in the strongest part of the current. I quite fancied shoving the camera underwater again and taking some pics...

Alternate Water-milfoil Myriophyllum alterniflorum - smart!

One of the water starworts Callitriche sp. - a difficult genus at the best of times

We continued across the moorland towards another hidden lochan, me with my eyes on the ground looking for any 'new' plants for the site list. Suddenly I stopped and gave Neil a quick call - bloody hell, there was a small patch of Lesser Clubmoss in the short turf! In January!!

Lesser Clubmoss Selaginella selaginoides - typically a late summer species up here!

I was a bit blown away with this, especially seeing as there were a number of young tips just erupting from the soil. The site wasn't especially sheltered and it wasn't a suntrap either. Bizarre. A great encounter, but yeah - bizarre!

One tiny lochan was little more than a Sphagnum dominated wet patch with barely any surface water to be seen. Scrambling through the Sphagnum and Soft Rush margins was lots of Bulbous Rush

Bulbous Rush Juncus bulbosus exhibiting viviparous flowerheads

Female bur of a Sparganium, probably erectum but possibly emersum - we're going to have to check this again later in the season to determine the species involved

Our final lochan was larger and deeper and had some sizeable pondweed leaves floating in the water column. Out with the grapnel and...

It looks pretty darn distinctive, but again I'm unsure what it is. I have a feeling these are the submerged leaves of Bog Pondweed, which look nothing like the floating leaves I'm used to seeing. But there weren't any floating leaves that I could see, and surely there should have been if it IS Bog Pondweed? I spent far too long last night going around in circles and getting nowhere with too many of the plants I collected yesterday. I'll come at it again with a fresh pair of eyes later. Here's a map of the lochans we visited, several of which I will revisit in the summer when things are in flower and the water levels lower. It's a great area and I bet it's totally unvisited by the tourist hordes that wander The Quiraing just a mile away. In fact, I bet you can hear them from this valley that lays beneath it

This is playing through my speakers as I'm writing this, it's a bit of an oddity but I quite like it. The sound of water at the start is quite apt for this post. I'm not convinced there's "gators or squid" in the lochans, but hey anything is possible up here! Hope you enjoy.