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[b said:
Quote[/b] ]I am no marine biologist
According to my CV some people would say I am, but you don't need to be a qualified biologist to digest the following info

[b said:
Quote[/b] ]
but I would guess that catching 129 porbeagle sharks would have more impact on their viability as a species than catching 129 mackerel.
An understatement! Sharks reproduce very very slowly in comparison to other fish, a porbeagle will bear 2-4 live pups generally between 60 to 75 cm long at birth after a gestation periodd of 8-9 months. Female porbeagles reach sexual maturity at an age of 12 years or older, while the males are mature at age 7. Average natural  lifespan is believed to be around 35 years, litters of pups are currently believed to occur on average every third year

Female Mackerel on the other hand are sexually mature at one year old and annually lay between 200 000 and 500 000 pelargic eggs 1 mm in diameter. Fry 3mm in size hatch at the end of an incubation period which lasts 6 days.

[b said:
Quote[/b] ]To the YD conservationist crusaders I would say don't forget the man in question has done nothing illegal
Many things that are now illegal used to be perfectly legal, such as drinking and driving, just because something is not illegal does not make it morally correct

[b said:
Quote[/b] ] I don’t know enough to know if 129 sharks are a large proportion or just a drop in the ocean
No but I'm sure your maths is more than adequate to crunch the numbers I've given above a new born female pup today would need to survive about 12 years before it could even add an extra one to the population so the effect of losing over one hundered animals will be huge

[b said:
Quote[/b] ]maybe he is a struggling fisherman who has just received a financial lifeline
Yes perhaps, and struggling Captains of Industry could get the same financial lifeline if we relaxed laws designed to protect our fragile environment from unmitigated pursuit of Mammon

[b said:
Quote[/b] ] It would seem that conservation and capitalism don’t work well together
Which is arguably the major challenge that our society faces today

[b said:
Quote[/b] ] Mind you, from what I have learned, it is just humans that are the problem – whatever the system
Couldn't agree more, and due to our population densities and rapid intercontinental travel, our society has never in it's history been more vulnerable to Nature's answer to problem populations - disease! If the SARS virus had had the same capabilities as the Ebola or other haemorraghic fever viruses the world might be a very different place.
 

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[b said:
Quote[/b] (Finless @ Dec. 05 2003,11:51)]It is easy to imagine that outbreaks of disease etc are a design safety feature to stop excessive expansion of a species. By luck or by design I wonder?
Design only if you're a religous type (which believe it or not I don't have a problem with shock ! horror!)

I prefer to think of it in terms of natural systems of biological organization, or as something as inevitable as gravity.
Of course being something of a short-haired hippy I'm still quite partial to The Gaia hypothesis
 

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[b said:
Quote[/b] (Dominic @ Dec. 05 2003,14:07)]VHEM has some excellent links - who's watched Austin powers and wished they could have their own MiniMe?
But I am Dr Evil and one day you and your offspring will all serve me and my mini-me baw haw haw haw haw....


PS Austin Powers is on this weekend, think it's sunday, can't remember which channel
 

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One upside to this disgusting practice is that we're now all aware of the damage being done right here on our own doorstep, I for one have just joined the Shark Trust, (20 GBP per annum) The following is from their websiteShark Trust

__


Porbeagle update

4/12/03
As many of you are aware for the past 4 days the Trust has been actively involved in a press campaign to highlight our concerns for the Porbeagle population targetted by Mr Ellis, the Newlyn Fisherman.

The Trust has worked hard to ensure news coverage has been balanced, and to date material has been aired on Westcountry TV, BBC news, Radio 5 live, BBC Radio Cornwall, Pirate FM, and in a variety of newspapers.

A number of you have contacted the office to ask what can be done and how you can contribute. The Trust would be happy to receive your comments(click on 'contact us' in the left hand margin).

News articles have been listed here on the website, along with reference material, and a response from a representative from the fishing industry (see below). In addition an active forum for discussion has been established with the Shark Trust forum, which is available for any individual to join and contribute to.

On a positive note after the Radio 5 Live interview a Shark Trust Trustee talked direct with Mr Ellis who expressed an interest in further discussion. The Shark Trust after all is not anti fishing, but pro sustainably managed fisheries.
 

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[b said:
Quote[/b] (Finless @ Dec. 07 2003,23:20)]If you do not actually know the figures then I don't agree that this is a reasonable assumption. I spent 45 minutes on line trying to find figures on the UK annual Porbeagle catch without success. Either I can't find it (highly likely) or the info is not available on the web. 129 could be anywhere between insignificant to disastrous.
Well.... I suppose if I had sufficient spare time  I could spend several days reading the latest data in the relevant journals,  then a further day or two distilling the must know info into a form easily digested by members of the public who haven't been trained in: Accepted Methods of Scientific Investigation, Population Genetics, Fisheries Management, Behavioural Ecology etc etc etc and hopefully end up with a simple version of    "Effects of unmanaged fisheries policies on the population dynamics of a West European squaline apex predator  Lamna nasus  (Bonnaterre) in UK Coastal waters"

Or I could more succinctly say "Trust me Bryan, 129 of an animal like this is most definately a significant proportion of the population."

My point it that this info is out there but unless you've got the training and the experience to decipher the way the scientific  community puts the info across (gobbledegook most would say) then you'd be hard pressed to recognise the source data you're looking for when you do find it.

Anyhoo... THIS would be probably the initial starting point if you wanted to find data like this


Stevil
 
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