Trying to catch mysterious Arctic animals…

Hey guys, I hope your summer is going great! 

Sophie and I went on holidays to Toronto for 12 days and did loads of fun stuff, including many trips and parties. Since getting back, the annual Quebec music festival has been on, where tomorrow night the legendary Billy Joel will no doubt rock the historic Plains of Abraham 🙂

It is also soon time for my next expedition to the Arctic.

On the 14th August I’m going back onboard the Canadian coastguard ship Amundsen for a 2 month stint at sea, once again sampling my favourite animals, the zooplankton…

The Canadian Coastguard icebreaker Amundsen, our home for the 2014 expedition!

The expedition, run by ArcticNet, a network of centres of excellence in research here in Canada, will allow us to find out more about the changing Arctic seas. We will sample remote waters of the Canadian Arctic; Nunavut and the dangerous Northwest Territories.

Some of the things I will do this year is to conduct an experiment on how much poop is produced by hungry copepods in summer (yeah I’m totally aware this sounds like a weird one). I’ll also use different gears to catch and take photos of zooplankton.

I’m especially going to try to capture chaetognaths (jelly worms in case you missed my previous posts) from water just above the seabed, where it seems like they might be aggregating…

Big chaetognaths (these white guys) can gather in very high numbers just above the seabed, as seen here in this pic from Saanich Inlet, Canada. Modified from Venus UVic site.

I want to capture these guys because so far almost all we know about Arctic chaetognaths (and a lot of other zooplankton), is based on capturing them in nets tows at least 10m away from the seabed (we avoid putting many of our nets so close to the seabed because we don’t want to damage them). But missing all the animals here is a shame, because one study suggested that maybe 25% of chaetognaths can live in waters 1-10m above the seabed. Photographs and ROV footage that I’ve seen personally support this.

It’s normally the biggest ones that live here, reaching lengths of up to 7cm (bigger than your middle finger). They could be having a rest in these deeper waters, which are probably less-turbulent than surface waters for large parts of the year; they may even reproduce here.

Some photos I’ve seen of these guys using a camera system called the MOKI seemed to show loads had copepod prey in their guts. These chaetognaths may have totally different adaptations that those in the waters above.

So I set myself the mission of trying to capture these guys. To do that, I’m going to use a device we designed for the cause. It’s a sampler we’re putting down there on a frame, which comprises two doors that can be triggered to close after a certain amount of time, by sending down a message from the ship. We might allow 30 minutes or so for our mysterious animals to (hopefully) go inside, before locking them in and bringing them to the surface. The frame also houses a camera so we can even watch them go in!

A pic of one of our camera systems (the LOKI, sister of its seabed version the MOKI) which takes photos of zooplankton that go inside it.

Of course, we are not sure about whether the chaetognaths will actually go inside the device (which has openings of around 30cm). But I’m hoping to using glow sticks to attract the animals inside the container (chaetognaths seem to be attracted to the direction of light).  My device also contains an anesthetic inside, which will put our animals to sleep, and eliminate any stress they might otherwise experience.

As you can see, there are a lot of ifs, but there always are when tackling new scientific challenges, and you know that applies especially to Arctic research. But I’m definitely excited to give it a go, and I’ll keep you all updated with my progress.

Who knows, maybe we’re on the verge of another chaetognath breakthrough!

Take care, Jordan x

 

0 Comments
Be the first to leave a reply!

Leave a Comment

* required