Again, I appear after months of radio silence! If you're a student or academic then you'll understand when I say 4th Year Honors Project...I've been pretty busy doing that as well as revising for exams at the end of April.
Last time we spoke I had just identified all the samples of freshwater invertebrates that I took from 3 streams on the Campsies. I did a little spot of data analysis and found what looked to be a relationship between where my species of interest (the Upland Mayfly) was found and the order of the stream it was found in. So we went back out in January to gather some more data (in the form of more kick samples) at a different location - on a tributary of the Culter, which was charmingly covered in a good layer of snow at the time :)
I've since tested this data but it's not really showing a similar pattern to the first lot, but that may be due a number of reasons, but not to worry! On the whole I'm finding the data analysis very confusing and find myself frequently doubting what I've done. It doesn't help that when I do a bit of internet research for help that it seems to constantly contradict what I've been taught in the past. There are so many statistical tests that you can carry out and so many that have certain assumptions that it's very easy to become overwhelmed and lose sight of what you are trying to do in the first place. I'm hoping to get a bit of guidance this week to put me at ease - or alternatively I'll have to do all my analysis again!
In other news, I managed to get back out CRIMPing again for the first time since November, mainly due to the weather over the winter, and general lack of free-time. The haul was pretty good but I did notice that there were a few freshwater hoglice and blackfly larvae, something that I've never come across in my samples since starting the monitoring program, however there were plenty of mayflies and stoneflies present indicating good water quality as usual.
Here's a photo of a nice big stonefly, one of two that we caught.
Well, into the breach once more dear friends, see you on the other side!
So....long time no post eh? Well I've been a busy bunny during the summer and more recently at university, now that I'm in my final year honors projects have kicked off and I'm currently in the midst of my own!
I knew I wanted to focus on riverflies and I had a helpful nudge in the direction of studying Ameletus inopinatus, an upland species of mayfly usually found in small streams above 300m. The experiment underwent many permutations in the planning stage but I've since been out in the field (the Campsie Fells to be precise) to do my fieldwork. I'm going to be looking to see if stream order has an effect on the distribution of the species, and then also look at the relationship between Ameletus and its freshwater habitat-sharing buddies.
Obtaining my samples was a sweaty job which involved gallumphing up tussock and moss covered hills which were riddled with drainage ditches and jaggy thistles, all while wearing chest waders, a fleece and rainjacket, just in case! Oh yes and lets not forget carrying the net and sample tubs - thankfully I had some expert help and only disappeared into a hole a couple of times.
See that little burn on the left? That's what I was trying to kick sample in :)
I collected 45 one minute kick samples in total, taken from 3 different streams and at various altitudes. Right now I'm settled into the lab work and steadily working through all the samples to pick out the inverts from all the moss and other guff I managed to catch in the net. Here's few snaps of the wee guys I'm discovered so far that inhabitt this seemingly bleak and empty habitat:
Nice juicy stonefly
Some microcaddis, or Hydrophilidae, their cases lok like seeds!
Caddisfly larva
Many of the inverts I find while sorting through the samples are barely a millimeter long, there are tiny limpets, snails, pea mussels and of course tiny riverfly larvae too. The next stage will be trying to identify and count the communities that I've managed to find, then it's onto the stats and trying to make sense of it all!
Today I did something I've been meaning to do for years - hunt for tardigrades in the garden!
Tardigrades are arthropods of the class Tardigrada, they are often called 'water bears' or 'mosspigs', which is where the name of my blog comes from. They are usually 0.1 - 0.5 mm long and can be found living in the damp moss or lichen that grows on trees and walls.
Since Unky Steve was kind enough to bestow me with a classic binocular microscope recently, so I thought there was nothing better to take it for a test run on than a tardigrade hunt!
In the garden i took a couple of pinches of moss from the garden wall, the bottom of a tree, and a pinch of green lichen from the same tree, putting them into separate small plastic bags to be examined later. I transferred the samples to three petri dishes and filled them with water to submerge the moss.
Samples L - R: Lichen, Tree Moss, Wall Moss
After leaving them to soak for a bit I started my search in the lichen but unfortunately the was nothing much to be found. In the tree moss sample I found myself in bear country, with my first ever tardigrade waving at me after only a few seconds of searching :)
The little white thing with stumps in the centre of the photo is a tardigrade, I promise!
Here's a video of the little guy, probably best to make it full screen :)
Tardigrade next to the tip of a mounted needle
Moss pigs are extremely hardy creatures, you might have heard
that some have been sent into space and have survived being outside in
the radiation and vacuum of outer space. They can also withstand
temperatures from just above absolute zero (-272.8) to above 100 degrees
Celsius, and are able to survive extreme drying out, or dessication, by going into a period of suspended animation called cryptobiosis from which they can be
reanimated just by adding water! It is thought that they evolved these
amazing adaptations in the move from the oceans, where they originally
evolved, onto land. It might be difficult to visualise just how tiny
these guys are, so see below for a comparison with a mounted needle.
Mounted needle with my forefinger for scale.
The tiny jungle of moss also harbors many other organisms, including countless nematode worms, mites and rotifers. Rotifers are also called 'wheel animals', as they have a structure on their head called a corona, which has loads of tiny hairs (cilia) used to sweep food into the mouth. Certain species (out of over 2000) of these guys called Bdeloid rotifers can survive long periods of dessication similar to the tardigrades. They also have strange sex lives and are able to reproduce without males (parthogenesis) which enables them to survive less favourable environmental conditions.
A rotifer.
The view down my microscope: Nematode bottom left, rotifer top centre.
You can read all about the remarkable moss pig in greater detail at this BBC article, and delve into the weird world of rotifers here!
It's been a busy 10 days out on the Glasgow University Marine and Freshwater Biology field course based on Millport, Isle of Cumbrae! The trip kicked off with a 3 day Environmental Impact Assessment module led by the adorable Peter and Azra Meadows. The task involved working as a group to assess the current ecological status of the sea floor around Hunterston Power Station in light of a (historically accurate but pretend) proposal to build a new coal-fired power station on the site.
Map of our beam trawl transects and sediment grab points
Being 27 students strong, it was admittedly a bit tension-filled trying to make decisions on how we we go about sampling but we got there in the end :) Four sample sites were decided on with a beam trawl and a sediment grab planned for each, with groups going out on the R.V. Actinia to see how it's done. The skippers Duncan and Tom were brilliantly knowledgeable about the area and the sampling techniques and had some great stories to tell.
While one group was out on the boat, everyone else was involved in the processing of the catches and data collection. It was a marine biology conveyor belt with sorting, identifying, counting, sifting, and weighing all going on at once. Of course it isn't all cuddling crabs and stroking starfish (!), we had some serious stats and report writing to do, as well as fit in lectures and briefings on what was coming up the next day - saying we were tired just doesn't cut it!
Our beam trawl haul!
Peter and Azra kindly provided a glut of wine on the Friday night so we all had a chance to cut loose for a time before the report was due in and the zoologist hoarde arrived the next day!
The Marine and Freshwater Ecosystems course kicked into gear on Sunday morning, when we headed out to Farland Point to collect some rocky shore specimens, and Kames Bay in Millport itself to dig for sandy shore beasties. At the rocky shore we took representative species from each zone - the Sublittoral (below the water line), eulittoral (between the kelp of the sublittoral and the furthest reach of the barnacles, and the littoral fringe (above the barnacles to the black lichen). We found a few shore crabs, common mussles, chitons, isopods, amphipods and anemones, as well a lots of different types of alga or seaweed.
At the sandy beach the fauna was dominated by some of my favourites - polychaete worms! The largest among the ones we found were estuary ragworms, which undulate from side to side with the wave of movement coming from the tail to the head. This means their heads are constantly waggling from side to side - they look hilarious.
Nephyts caeca - a polychaete worm
Monday saw us back out on the Actinia to collect some plankton samples and measure light availability below the surface of the water. On Tuesday we were briefed about a scientific video we had to make, testing our skills in presenting a scientific paper in a fun an engaging way - the results of our efforts were screened on Friday afternoon and I had no voice left from laughing so much. You can watch the masterpiece that is CSI: Millport below, let us know what you think!
We also had a chance to check out our plankton samples under the microscope. Plankton are tiny organisms, and can be photosynthetic plants (phytoplankton) or larval forms of sea life (zooplankton) that are carried by the ocean currents. We found diatoms with surfaces made of sillica, dinoflagellates, tiny polychaete worms and crustacean larvae wriggling around in a tiny drop of sea water, a world within a world.
Gammarid and polychaete worm larvae under the microscope
Squat lobster and a dragonet fish
Wednesday saw us in the lab for some microbiology work on two water samples to see if E. coli and other colliform bacteria would grow on agar plates. Our results were very different from previous years success as we hardly had any colonies growing overnight at all. I must admit that microbiology is probably wasted on me, I like my study subjects to be visible ;) In the afternoon though our groups choose different rockpools and we collected hermit crabs from a .25m quadrat, painting their shells with colourful nailpolish before releasing them back to their pool. We would return the next day to see if they went for a wander to see their neighbours or not. That afternoon we also did a 75 minute study on oyster catchers, watching one bird to see how much time it spent watching for predators and feeding. Thankfully the weather was great if a bit chilly and we were rewarded with a lovely sunset before we headed home for tea. Wednesday was also St Paddy's and after the fieldwork was done we headed to the pub to celebrate - what we didn't expect was the pub running out of Guinness minutes after we arrived!
Looks like I should have used some of the polish myself
On our penultimate day we went to check our rockpools and try to find our painted hermit crab pals. Our group found 2 out of 5 that had been painted and about 15 other unpainted crabs which had moved into the area. The two that we found had moved out of their shells - maybe they didn't like the lavender colour?! We also conducted a quadrat hurling rocky shore survey where we flung the wire square over our heads and counted how many periwinkles, mussels and limpets were within the boundary. In the evening the tutors held a fun but competitive review quiz, complete with table wine. Our team came joint second with 31.5 points out of 40 which wasn't too shabby!
Friday came after what seemed like months of work, dry ham sandwiches, hangovers, copious cups of tea and no sleep. There was a last minute rush to finish some group videos and then experience the enjoyment of everyone's hard work in a dark and stuffy lecture theater while the moon covered the sun behind the clouds outside. I may have almost lost track of all the things we learned but I had an absolutely fantastic time which I will never forget!
Taxidermy reprise: here's a lady stoat completed this week, carrying a wee field vole which was found along with the stoat when it was caught (in a legal, lethal spring trap, though not by me).
Teeny vole pelt
If you'd like to see more you can head over to Stuff Stef Stuffs facebook page :)
I have, in my time kick sampling, come across more than a few amphipods of the Gammarus pulex variety with bright orange patches showing through the side of their body, and have never known what they were - UNTIL NOW!
Gammarus pulex showing infection with Pomphorhynchus laevis.
Through the magic of learning (which is fun by the way) in the form of lectures on parasite biology at university, I am now excited to share that these orangey bits are actually internal parasites! Going by the beautifully unwieldy name Pomphorhynchus laevis, the eggs of these acanthocephalan (spiny headed) worms are eaten by, and make their way into the gut of unsuspecting Gammarids (freshwater shrimp). What is particularly interesting about these parasites is that they can change the behaviour of Gammarus to increase their chances of making their way to their definitive host - a fish. It has been shown that the bright colouration of the infective stage of Pomphorhynchus laevis is more easily spotted by fish such as trout and three-spined stickleback, the natural predators of Gammarus in streams and rivers. The parasite also changes the normal behaviour of the amphipod, causing it to be less sensitive to light which results in it spending more time in the open, or against light coloured gravel. It may also alter its sense of smell, making it unable to detect the scent of predators and flee. This makes them 'sitting ducks' so that hungry hunting fish can easily gobble them up!
You might think this is bad news for the parasite, when it is actually exactly what it wants as it ends up in the gut of its ultimate host where it is able to reproduce, release eggs which are expelled in the fish's faeces and start the cycle all over again. Some parasite species have extremely complicated life histories, going through many life stages in different forms and enduring exposure to different environments. For me it's a marvel how intimately parasites and their hosts have co-evolved over millions of years: developing adaptations to their host's immune system to avoid detection and death, ensuring that the next generation is spread to where the intermediate host will be, and also in some cases altering their intermediate host's behaviour in order to get where they need to be for the next life stage.
A scary acanthocephalan worm (From http://www.carlsbergfondet.dk/~/media/Images/Forskerartikler/torskens%20spaende%20indre%20liv/lille%20illustration_version%201.ashx)
Of course it can be bad news for the infected fish if it ends up with too many hangers on inside its gut! A heavy load of spiny headed worms can reduce the weight and condition of the fish host and eventually lead to death.
Ahem. Well it's not all doom and gloom, our hook-headed pal has enabled some cool strides to be made in healing wounds. The hooks have inspired a micro needle design which can be used to attach skin grafts which are less damaging and more secure than conventional surgical staples. Also other parasites are being used in trials to treat autoimmune disease such as MS.
Huzzah for parasites!
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I received a series of Jacques Cousteau DVDs for Christmas this year which was an excellent present for a budding marine & freshwater biologist ;)
If you did not already know, Cousteau was a French naval officer, explorer, conservationist, scientist, filmmaker and researcher who along with Emile Gagnan developed the aqualung (or SCUBA system as it is known today) in the early 1940s. He was also a pioneering marine biologist and traveled the oceans during with his son and crew on the adapted marine biology station ship, Calypso, for the series The Undersea World of Jacques Cousteau between 1966 and '76. He developed mini submersible exploration vehicles which were launched from Calypso and enabled him to film amazing scenes of life underwater and bring attention to the negative human impact on the oceans.
He also predicted the existence and use of echolocation in porpoises as he observed them finding the optimal course through the Straits of Gibraltar without following a boat. He certainly was a busy monsieur!
Of course marine biology was a bit different back then, and some of the 'techniques' used to study the animal life would definitely be frowned upon today! Here are a couple of examples:
Trapping tropical fish under plastic domes while their natural predators try to get at them and eat them.
Prodding a pufferfish until it inflates itself.
Drilling a hole at the rear of a turtle's carapace (which does not cause the animal any pain) and tying a hydrogen balloon to it to track them.
Attaching a plastic ball float to a fin whale to track it, combined with divers hanging on to its tail and fin for a bit of a ride before they let it go about its business.
Securing a tag to a juvenile sperm whale with string around its body.
Monsieur Cousteau riding a turtle, as you do.
Despite the perhaps slightly dubious methods, there are many fantastic insights into the deep sea including a couple of species and behaviours that I hadn't seen on other natural history documentaries (even recent ones) before.
An additional bonus for me was that the series is narrated by Rod Serling of The Twilight Zone fame, which, for those that are too young, is referenced in Futurama's The Scary Door! The series is seriously worth a watch :)
Next up on Mosspig - the first CRIMP survey of 2015!
