So what have we been up to? It all blurs together… let me check my activity log…
Ok, the weather calmed enough for us to finish deploying the moorings (4 in all), and yesterday (Sunday) started with a dawn CTD cast (measures salinity and temperature through the water column, and collects water samples through the water sample for all sorts of experiments by the other scientists (will find out more about their work & see if I can explain it in the blog later)). There were also bottom cores (takes a chunk of the bottom up for the benthic scientists to pore over), zooplankton collection…
…zooplankton… more of that now – it’s part of our project looking at everything from zooplankton – fish – marine mammals & seabirds. Beth’s in charge of zooplankton collection, and it involves towing something called bongo nets through the water (or the rest of us call them ‘giant’s tights’… because that’s what they look like (see photo on left)). These very fine nets are lowered through the water column to the bottom & then dragged back up & collects all the very small little creatures out of the water column – the tiny little animals that feed on plankton and other micro-animals… there are Calanus species (bugs that swim around very rapidly & vitally important animals in the food chain… species from sandeels up to 20-30m long whales eat these microscopic animals (I’m talking only the size of a millimetre or less)). Then there are the larvae of lots of other animals – so your baby crabs, baby fish, baby wormy things (which are cool – they look like translucent feathers that wiggle), and of course baby & small jellyfish… and lots more including cheatognaths… ever seen ‘Alien’ the movie? These translucent innocent looking creatures are actually voracious carnivores, and have a proboscis with a mouth on the end of it that comes out of their mouth to snatch up prey (thank goodness I’m not a zooplankton!) That’s just a few of the many creatures Beth found when she brought up her ‘tights’ out of the water. And it really is zooplankton soup
out there … so much plankton (see picture on right of the inside of the end net – the cod-end... all that brown stuff is zooplankton)! Nice to see some life down there! COOL STUFF!Why bother trying to find out about zooplankton? Well above the phytoplankton (micro plants), they’re the base of the food chain, so they’ll be the critters that attract fish that eat them, and the predatory fish that eat those fish, and the marine mammals & seabirds that feed on them all. So hopefully, where there are lots of dense aggregations of zooplankton we’ll find lots of fish, marine mammals & feeding seabirds (ok… I admit we haven’t seen any marine mammals and not much bird feeding activity yet… but well… that’s the idea anyway… and the weather has been a bit naff…).
Left: Beth & her zooplankton 'tights'Lots more has been going on – we had a 25 hour stationary monitoring point during which Beth & I watched the fish echosounder and got overly excited by all the nice big fish schools, others got excited (or terribly bored) lowering and raising the turbulence profiler (aka the chimney sweep) through the water every 5 minutes, and the birders sat patiently watching the birds fly past. So lots of activities going on continuously – a real hive of activity. I’ll try and explain the different aspects as we go through the survey.
But now, after a beer in the bar, it’s time for bed… and tomorrow for more adventures.
:o) Clare
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