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Shark Populations

Joined
Apr 8, 2004
Messages
287
Hello all, sorry to be a bugger with this and have to ask all you cephy people but I'm about to do TV and Radio interviews about why Smoothound (Mustellus asterias) populations have gone down and will be saying that it is probably down to more destructive fishing methods taking cxrabs, scallops and whelks...

are there any other examples of benthic, invert feeding sharks losing numbers anywhere else in the world??

Anyone know of any smoothounds captive bred recently????

Anyhoo, thanks in advance!

~Andy
 
Joined
Jun 3, 2004
Messages
486
Re: Shark Populations

Andy Lister said:
Hello all, sorry to be a bugger with this and have to ask all you cephy people but I'm about to do TV and Radio interviews about why Smoothound (Mustellus asterias) populations have gone down and will be saying that it is probably down to more destructive fishing methods taking cxrabs, scallops and whelks...

are there any other examples of benthic, invert feeding sharks losing numbers anywhere else in the world??

Anyone know of any smoothounds captive bred recently????

Anyhoo, thanks in advance!

~Andy

I can probably help you there what kind of info are taking about, just quotes or actual papers?

I've got a review paper that mentions something regarding the decline in biomass of the 10 most common bycatch species in orange roughy fisheries. One of them's probably a dogfish of some kind. It's in the office so I won't be able to check till tomorrow.

I think I might have something from Australia as well... but I can probably get cream for that :P
 

cthulhu77

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Mar 15, 2003
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I didn't know smoothounds had ever been bred in captivity...I have heard of some horn sharks producing, but even that, rarely...would be a cool sight to see!
 
Joined
Jun 3, 2004
Messages
486
Hi

This comes from: The effects of commercial exploitation on orange roughy (Hoplostethus atlanticus) from the continental slope of the Chatham Rise, New Zealand, from 1979 to 1997.

Malcolm R. Clark, Owen F. Anderson, R.I.C. Chris Francis, Dianne M. Tracey

Fisheries Research 45 (2000) 217-238

Baxter's dogfish Etmopterus baxteri Biomass estimated in 1984:770t. Fraction of said biomass in 1994: 0.26

Pale ghost shark Hydrolagus sp. Biomass estimated in 1984: 470t. Fraction of said biomass in 1994: 0.16

Please note this data is ten years old now and I've left out a lot here. I hope this is of some use. These are only intended as sound-bites.
 

TPOTH

Vampyroteuthis
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Joined
Jan 22, 2004
Messages
280
Re: Shark Populations

Matt Jones said:
I think I might have something from Australia as well... but I can probably get cream for that :P

:roflmao:

Back on topic... in general all shark populations are decreasing (general trend for anything marine really). Benthic feeding species are especially at risk if in areas of bottom trawling as they aren't very fast swimmers and can't escape the net. What's worse is that, should they be taken as bycatch, they generally don't make back to the sea in good shape as shark fins go for a pretty penny those days.

As Matt said, depends if you're after papers or quotes (or soundbites as Master O would put it)... and how discerning is your audience supposed to be :wink:

TPOTH
 
Joined
Apr 8, 2004
Messages
287
Thanks for that guys!

I'm just after figures really, papers that can back them up would obviously be good but anything would be great, it's for BBC News interview that I am doing...

Cthulhu77, if it is the first time ever then thats spankingly good! Would be nice to have that one on me! :P

They are munching on live prawn and rag worm at the moment, and taking as much frozen mysis as they can cram in their little guts!

I'll try and get some piccies!

~Andy
 

cthulhu77

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Mar 15, 2003
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Hats off to you, sir...that is one hell of an accomplishment ! I did some checking around, and was told that they have not been captive bred yet...at least on this side of the pond.
:notworth:
greg
 
Joined
Jun 3, 2004
Messages
486
Hi

When is this bbc thing? I'm a bit busy right now with an orange roughy lit review. I'm pretty sure I've come across papers with numbers etc... I'm reasonably sure I've got something that says over the last 25 years we've reduced the numbers of big sharks by 75% or something similar.

I'm free next week (finished, or dead, or both) and it will be a nice change to look at something not reddish-yellow and coarse.

Did you know... that they used to known as the Slimeheads? Strangely enough, marketing people in NZ didn't think that would sell in the 80's.
 

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