WEBVTT

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My name is Kelly Walker. 

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I’m a fisheries grad student

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and my role on this cruise is to run the bottom trawl net

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to collect samples of fish and benthic invertebrates.

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It’s a plumb staff beam trawl.

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so it’s a beam trawl net.

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Specifically on this net. it’s a three meter beam.

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so it’s only about nine feet. less than ten feet. long.

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And. as it’s going along on the bottom. 

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there are floats on top that keep the top of the net open.

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And. essentially. it’s just dragging along the 

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bottom to collect the sample of fish or invertebrates. 

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And then you tie the net shut at the end 

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with a simple daisy chain knot

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so you’re able to quick release it 

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once it comes up on deck 

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with the big bag that you usually have.

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Before we take the catch out of the trawl net itself.

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we like to rinse out the mud.

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And most of the time it’s very watery mud 

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and the stuff that’s not going to rinse out 

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often has organisms caught in it.

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And so by kneeing it or kicking it. 

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along with spraying it with the hose. 

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it’s able to get most of that fine grain sediment 

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out of there so it’s easier to rinse 

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once we get it out of the net.

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It’s a pretty good way of mass sampling 

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what’s down there because you can get 

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a really good count of abundance and biomass of. 

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specifically. benthic invertebrates and benthic fishes 

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is really what it’s good for sampling. 

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Smaller trawls are a lot easier to use 

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than larger commercial fish survey trawls. 

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Even other scientific trawls can be a lot larger than this

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and it’s not dragged for as long. 

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Our nets are only dragged up to 

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forty five minutes and those go on for hours.

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One of the most challenging things. 

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especially this trip. has been the ice.

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I really can’t trawl with heavy ice cover

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because there’s a really strong possibility 

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of an ice floe taking the wire and it can break the wire.

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It can really damage that trawl wire. 

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And then. also. a really big challenging thing. 

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specifically about the Chukchi and Beaufort Seas.

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is the sediment type that’s down here.

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It’s really thick mud and we have been 

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able to modify our plumb staff beam trawl net by 

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putting a set of roller gear on them and. 

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essentially. they’re like tiny little tires 

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that just roll across the sea floor

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instead of digging in like the net. 

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if it was unmodified. would do. 

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Another challenge is fishing at depth. 

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You have to think about putting more 

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weight on the net to make sure it 

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actually gets down to depth.

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and then you have to make sure that 

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you have enough floats on that net to 

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make sure it doesn’t just close in on itself.

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and that the net is not just going to 

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sink into the seafloor with all 

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of that extra weight on it as well.

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So. depth and sediment type and ice 

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I think are the three main things that 

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are the most challenging up here. 

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I think it’s really important for women 

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to keep getting involved with science.

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Get out there and get muddy. that’s a good one.

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That’s exactly what we do.