Electrofishing health-check of the River Cale with Wessex Water
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Electrofishing health-check of the River Cale with Wessex Water


C.A.T.C.H. Community Action to Transform the Cale Habitat So Andy, I’m Matt from C.A.T.C.H. Hi Matt, Andy, Wessex Water. Wessex Water, right, ok. We were talking about the reason for doing
today and back in 2012 we did an electrofish with the Environment Agency and we pulled
the sum total of five fish out of this river, and that was mainly due to an environmental
incident in previous years from a cheese factory, a local cheese factory in the town. It killed
off an awful lot of fish in the river, so in conjunction with the Environment Agency
we agreed to have a count, and unfortunately that’s what we pulled out. How about the eel? Where was that eel from?
Was that later? That was later, that was further upstream
actually. That was north of the pollution incident. Do you want to explain what the purpose of
this is? Yeah. I understand you’ve had some more fish
put in. Some chub and roach. And Dace. Several thousand? Four and a half thousand, yeah. Hopefully those fish are there and there are
reports that the fish are still around; certainly the chub, and so we’re going to fish a hundred
metre section and actually count how many fish are there. We’re also going to have a
look see further upstream and downstream just to see how many different species we can find
and get some idea of the density of fish to see whether they’re reproducing. So as to see an improvement, yeah. Great. These photos here are from the restock that
we did. And this is the Environment Agency? This guy here is from the Environment Agency
and he turned up with his IBC and pumps and stuff full of two inch long fish, and as a
result of that we involved the local schools on that. We contacted all of them and it was
great because the kids were able to come down and scoop a net full of fish into the river
and it was great. Somebody asked us the other week how much
it costs to run C.A.T.C.H. and we were like, well it can cost nothing or it can cost a
fortune. It depends what you want to do in the river. If you’re litter-picking and balsam
pulling and all that sort of stuff, I mean these rock deflectors; they were all in the
river. So it’s just shifting rock. Yeah, exactly. Excellent. There’s a lot of enthusiasm for it. Good. I’m going to go and get my waders on. Yeah, I’m starting to sweat a bit now. We’ve got a battery here that powers this
compressor that will run this aerator, so we’ll keep the water nicely oxygenated so
any fish we do catch can live in there quite happily while we finish off the survey, and
then we can measure them and count them at the end of the survey. This is backpack electric fishing equipment.
You get two sorts; this is backpack, a tradition sort uses a little generator and then you’re
restricted to the generator by a lead. This gives you a bit more versatility because you’re
not tied by long leads as to where you go. So a battery in there. This is like the control
box and we have two nodes. And these are the things that put the charge
into the water. That’s right. We’ve got an on-off switch there.
Then there’s a cathode which is this braded copper wire, which trails behind. So the current
goes between the two, fish are attracted towards the anode, repelled by the cathode. So the idea is I’ll be walking through from
the stop net which is just downstream of the bridge there. Walking up through pressing
the switch. It emits a high-pitched beep whenever it’s on. Whenever it’s on, don’t have your
hands in the water, basically. If you are going to put your hands in the water, tell
me before you do to prevent me from turning it on and giving you a bit of an electric
shock. Fish that are within about a metre from here
are actually attracted towards the anode. When they get closer, when they’re about a
metre away they get an involuntary swimming reflex where they actually swim towards the
anode. Ideally you net them then because they’re minimum stress to the fish. As they get closer
to the anode, they go into tetanus, so they actually go into spasms. Ideally you catch
them before they get into that situation, but they still recover from that tetanus.
So you can still net them and put them in oxygenated water and they recover. Two buckets. Right-oh. Yay! We’re off! How far down the river are they going? A hundred metres. This is a stone loach here; the long skinny
one. Beautiful. We got a stone loach Soph! Oh, hang on! Couple more in there. See, we’ve already topped what we found
on the last electrofish back in 2013. You can guarantee we’re missing loads because
we can’t actually see anything. No, no, that’s the snag isn’t it. So it’s guesswork really. Is anybody nerdy enough to know the name,
the Latin name of the fish? Cottus gobio is bullhead,
I don’t know stone loach. There are tonnes of bullhead. Shall we just let the bullhead go? We’ve got enough. We’ll be here all day otherwise.
So that’s a great sign. That’s really nice. Good news. Do you think it’d be a good idea to get one or two
of those in an aquarium on the table? Yeah, can do. We’ve got stone loach and masses of bullhead
at the moment. Oh, good. Found some fish! We’ll leave them be I think. I think we’ll just
have to say that there are a lot of bullhead, and a lot of stone loach. Alright Andy, that sounds good. Hopefully we’ll catch something a little larger. Might as well see how many different species
we can get. Sorry Dave, you alright? Oh! We’ve got a signal crayfish. Oh, god! Did you know they were there? Yeah, we did unfortunately. So these are the invasive American crayfish. Oh wow. I’ve never seen such a thing. And they’re called signals because they’ve
got red claws that they signal with. Tell all they’re competitors to back off. Back off, indeed. Shall we put it in there? Yeah put it in, it’s interesting for the children
to look at isn’t it? Definitely. This is a roach. Beautiful isn’t it? Yeah, they’re lovely fish and they grow a
bit bigger. One way you can tell these is the really
orange eye, and slightly orange fins. These are roach, these ones.
So they will feed on little insects,
they’ll feed on things like silkweed as well. So what feeds on them? So, again, when they’re smaller, perch will
eat these, and pike as well. Well they’ll eat anything won’t they? Exactly, they’ll eat fish this big quite easily. Isn’t it for camouflage, their cases? Yeah, the cased caddices build a case for
camouflage and just all-round protection really. You can get species that don’t build a case.
They tend to be a bit bigger. That’s a case, yep. I’ll try and get it. See if we can find one made out of twigs and
stuff. I find they’re really interesting. We’ve got a cased caddice over in this one
and it’s moving about. They can get bigger than that. Shrimp? Yeah. Like what we eat. Oh no, no, no, they’re different, yeah. That’s
about as big as they get. They’re not everywhere, but wherever they are they tend to be very
key to the, lots of fish like to eat them. I am so pleased with this. Look at ’em! Look at ’em! I know! Aren’t you? Yeah, god yeah! Yeah brilliant mate, we’re doing really well. There you are Dave. That’s what they’re like
when they’re stunned. Are you going to go down by the basketball
court? We might not need to now, Tom, we might have
got enough result from here. This here is where the monsters live under
this bridge. They haven’t caught nothing! I can see what one of them now! Yeah! Nothing at all? Probably because whatever’s
down there is so big it’s just not affected. Matt, come on, you forgot to put water in
the bucket. Yeah there’s some big ones over there. It’s interesting to know where we’ve got poor
coverage of fish, though, isn’t it? Very much, yeah. I mean in low flows we often
see them here don’t we, because you get that little bit of flow coming out of the outlet
there, which curiously is not running. Might be a bit too deep. Oh, a kingfisher! Did you see the kingfisher?
Kingfisher just came! Oh kingfisher, really, yeah? He’s like “Oi, that’s my breakfast!” Yeah! Shall we go and have a review of… Yep. We can get up here. I think as we get them out, put them into
a bucket then people can ferry them back into the river. A line of buckets is what we need guys. Do you want to catch the fish? Ok, yeah. Go on Tom. Nothing. What have we go in there? What is that? A little fry. A little baby minnow. Excellent first catch. I would think 20mm minnow. There we go. So this fellow is, we’ll do it in millimetres,
130. And what it is? It’s either a chub or a dace. Let’s have a
look at his dorsal fin there. Oh yeah. And it’s a chub. Try a bit deeper. Ok, another minnow. So we’ve got a roach, roach 170. Alright, big, big chub of 215. A roach of 185. And a chub of 180. Can we start ferrying those back? Go on, go and have a go. Dig deep, right down to the bottom. Lovely. Woo! Look at that. There she blows! What have we got there then. Are we gonna
have a guess at what fish that is? What do you reckon? It’s a chub. Ah, I think it is a chub. It’s a small chub.
So that’s 158 chub. It’s just such a great result. It’s a shame
the weather wasn’t slightly better because we’d have had a huge amount of
people in the play park. It’s just good to have that level of interest. Yeah there’s still been a good amount hasn’t there? It’s not so bad, having more fish than people. Yeah, more fish than people. That can be your tagline! Once we’d finished the electrofishing on the
100 metre stretch in the park area, we decided just to do a little bit of
spot electrofishing further down. The delight of the day, to say the least,
was a beautiful brown trout that came up whilst Andy was doing his survey, into the net, which was absolutely fabulous. Now, the reason for that being so good is
if the river can sustain brown trout then everything else species-wise
should fall underneath, so it was a good result for the group and
a great moment. Unfortunately we didn’t get it on the video. Dave was further upstream fiddling with his cameras, but we have got this nice photo. Ok then folks, well, here we are at the end
of the day. We’ve done the electrofish down through the stretch of the Cale, through the
recreation ground. You’ve obviously seen the rest of the footage. It’s been a great day.
I’m pleased. I’m pleased as punch. What we’ve found today is beyond all our expectations
and it’s certainly going to do well to spur the group along and it gives a good indication
of what’s going on in the River Cale. Obviously I’m hugely thankful for
everybody who’s come down. Andy’s the expert so he’s going to give us
a little bit of a summary of his feelings of how the health of the Cale is. Andy is,
what am I trying to say. His opinion’s more important than mine,
let’s say that. So over to you my friend. Yeah, all in all a very good day. Lots and
lots of small fish, which is ideal. A lot of bullhead, minnows, stone loach;
way more than we could catch and count. Probably about two bullhead per square metre,
about one stone loach per square metre. That’s a lot of fish. Probably more than we’d see in most of our rivers. And then on top of that, quite a few chub, roach, dace and a brown trout, so I think we’ve got seven species in total,
and all-in-all looking very healthy. That’s great news. So as Andy says, all-in-all it’s wonderful to find a brown trout is incredible. I was fishing the river when I
was probably about 12 so that’s obviously not that many years ago. I’ve never seen a
trout in the river so to see that come up today is just fabulous, and I’m very very
grateful to everyone who’s come along. Very grateful to Wessex Water, very grateful to
the Stour Catchment Initiative, very grateful for Dorset Wildlife Trust, and everybody who’s
come down, and the Environment Agency always incredibly useful to us and very good with
information and knowledge and spuring us along, so thank you very much to them, and it’s
been a good day. Watch this space. More to come! Good man. Natural. That man should be on TV. Did I mention everybody? I didn’t forget anybody
did I? I thought you’d forgotten the EA.

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