Sharks Swim Closer to extinction

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Having watched the precipitous decline in shark numbers around my island for the last 40 years, it is a very sad story and one that hits home for me.

However, I think the West is often too quick to judge Asian cultures for the practice of shark finning. I'm not suggesting this isn't a fairly despicable fishery IMHO. What I am suggesting is that we are all responsible for the decline of shark species, often in ways that aren't clear to us.

Many of the sharks killed each year die as bycatch, non-target species in other fisheries. Those of us who consume the target species from those fisheries are also indirectly complicit in the decline of sharks around the world... and that includes me.
 
Many of the sharks killed each year die as bycatch

I hope you aren't offended that I would ask you to justify this claim with some numbers? It seems to me like bycatch is a very, very, very, very tiny problem compared to floating finning factories.
 
I hope you aren't offended that I would ask you to justify this claim with some numbers? It seems to me like bycatch is a very, very, very, very tiny problem compared to floating finning factories.

I think Dr Bill is correct in that we are all partly to blame. However I do know that the commercial fishermen have had more restrictions put on them in the last 20yrs in the name of conservation (IMO still not enough), but on the other hand Asian finning practice seems to have increased.

I think the problem is about to get worse, see this thread,

http://www.scubaboard.com/forums/marine-life-ecosystems/234889-shark-finning-legal-oz.html
 
I hope you aren't offended that I would ask you to justify this claim with some numbers? It seems to me like bycatch is a very, very, very, very tiny problem compared to floating finning factories.

It has been estimated that more than 100 million sharks are killed globally by humans each year. It's believed that roughly half of that is bycatch.
 
It has been estimated that more than 100 million sharks are killed globally by humans each year. It's believed that roughly half of that is bycatch.

I'm not really interested in matters of faith. I've seen numbers of sharks killed last vary from 36 million to 100 million. If 50 million sharks died to bycatch alone, thats still 14 million more than the total lowball number estimate.

Shark finning estimates are based on several vectors including sales reports. Bycatch numbers are much harder to try to estimate.

Oceana.org uses the high 100 million estimate and I can find no scientific methodology on their site to justify the 50 million (or half) number.

I understand how blue sharks in particular are susceptible to longline fishing and how sharks/rays are hurt by trawling. I am wary of bad statistics even more since they can be turned around to discredit one's point of view.
 
I'm not really interested in matters of faith. I've seen numbers of sharks killed last vary from 36 million to 100 million. If 50 million sharks died to bycatch alone, thats still 14 million more than the total lowball number estimate.

Shark finning estimates are based on several vectors including sales reports. Bycatch numbers are much harder to try to estimate
.

Oceana.org uses the high 100 million estimate and I can find no scientific methodology on their site to justify the 50 million (or half) number.

I understand how blue sharks in particular are susceptible to longline fishing and how sharks/rays are hurt by trawling. I am wary of bad statistics even more since they can be turned around to discredit one's point of view.

The above it seems it would be as easy to get by catch numbers as it would LEGAL shark fishing, however illegal fishing of any kind?
 
Dr. Shelley Clarke has calculated that between 26 million and 73 million sharks a year are killed for their fins. This is based on fin trade in Hong Kong markets.

These numbers do not include fins that are not involved in trade, sharks that are killed for their meat or liver oil or sharks caught as bycatch.

Some studies have shown that the bycatch of sharks has equaled or surpassed the commercial catch of targeted species (1). It is estimated that tens of millions sharks, possibly half the global catch of sharks, are caught annually as bycatch in other fisheries; yet, it fails to appear in fishery statistics and the bycatch remains unmanaged (2,3).

1. Hinman, K. (1998). Ocean roulette: Conserving swordfish, sharks and other threatened pelagic fish in longline-infested waters. Leesburg, VA: National Coalition for Marine Conservation.

2. Bonfil, R. (1994). Overview of world elasmobranch fisheries. FAO Fisheries Technical Paper. No. 341. Rome: FAO. <http://www.fao.org/docrep/003/v3210e/V3210E00.htm#TOC>

3. Stevens, J.D., Bonfil, R., Dulvy, N.K., and Walker, P.A. (2000). The effects of fishing on sharks, rays, and chimaeras (chrondrichthyans), and the implications for marine ecosystems. ICES Journal of Marine Science 57:.474-494.
 
Papers which I am familiar with. Most of the bycatch estimates I find are local estimates. The WWF says 3.3 million sharks are killed a year in the Pacific as bycatch but I can't source their numbers.
 
https://www.shearwater.com/products/perdix-ai/

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