Maybe not quite yet
But getting pretty close
One thing, however, is for certain – great white shark numbers at many locations are plummeting due to overfishing, .
Sharks do not have the capability to repopulate quickly.
They are slow to reach maturity and when they do they produce only a few young per year.
They simply cannot tolerate high rates of mortality.
.
If all fishing were to cease, modeling results from the 1998 stock assessment indicate that there is less than a 50:50 chance that these shark populations could recover to their MSY level (the "sustainable" level or that which responsible fishery managers would never let a population slide below) even after 30 years!
.
Nearing Extinction - The species in the greatest danger of slipping into extinction is the western north Atlantic population (stock) of blue-fin tuna.
.
Thanks to 4 decades of overfishing, it has been driven to just 3% of its 1960 or pre-longlining abundance - a decline of 97% (ICCAT is the international commission that claims management authority over all tunas, marlin, swordfish and the other big fish of the Atlantic) In comparison to blue-fin,
.
Atlantic white marlin abundance has been driven to 6% of its pre-longlining abundance, and Atlantic blue marlin has been driven to 20% of its pre-longlining abundance.
.
Long lining is the current favoured method of fishing whereby set lines of over 100km are common
Yes that's over 100km of line.
Attached to it are literally thousands of baited hooks.
An estimated 1 billion hooks are set annually by the world's longline fleets.
Depending on the type of long line, buoys, floats and/or weights are used to position the line on the seabed or at the required depth in the water.
.
Of course modern radar and other aids mean that the fish have no chance, hence the continuing rapid decline in numbers
.
For a long time, the north Atlantic swordfish stock has been declining more rapidly than any other marine species.
.
It has been steadily doing so at the same rate each year for the past 20 years!
.
Destruction of this population has been meticulously documented each year for ICCAT by its scientific advisory committee.
.
Yet ICCAT has failed limit the catch of its member states sufficiently in order to produce its stated management objective - the maximum sustainable yield or MSY
.
The cause of this decline in abundance is excessive fishing pressure by commercial fishing fleets.
.
By 2000, it had grown to 4 times higher than the sustainable level or MSY .
.
Fishery managers should never allow fishing mortality to remain above the MSY level.
.
Populations of the "Large Coastals" are Down by 50 to 80%
.
The population status of most "large coastal" shark species of the U.S. Atlantic coast (39 species) is less well documented than those for Atlantic swordfish, other billfish and tunas
.
But, they appear to have declined even more severely and in a shorter period of time.
.
These include many familiar species such as hammerheads, bull, lemon, blacktip, sandbar, nurse and great white.
.
It is estimated that the large coastal shark group has declined from roughly 9-11 million fish in 1974 to an estimated 1-2 million fish in 1998 or about 30-36 percent of the population size needed to produce the maximum sustainable yield (MSY).
.
The status of the "pelagic" shark group is unknown. It includes the makos, porbeagle and blue shark.
.
OK so politically those responsible refuse or are unable to control or ban the fishing of these endangered species
And of course this is not in isolation from everything else in the world's oceans where the impact of this slaughter is not yet understood in its knock on effect
What is clear is that humans are wiping out a major source of food
Humans are destroying millions of years of evolution
Difficult to see what can be done at this late date given the lack of imagination and political willpower
Still you can always tell your children that you once saw live fish swimming in the ocean
What a mess
But getting pretty close
One thing, however, is for certain – great white shark numbers at many locations are plummeting due to overfishing, .
Sharks do not have the capability to repopulate quickly.
They are slow to reach maturity and when they do they produce only a few young per year.
They simply cannot tolerate high rates of mortality.
.
If all fishing were to cease, modeling results from the 1998 stock assessment indicate that there is less than a 50:50 chance that these shark populations could recover to their MSY level (the "sustainable" level or that which responsible fishery managers would never let a population slide below) even after 30 years!
.
Nearing Extinction - The species in the greatest danger of slipping into extinction is the western north Atlantic population (stock) of blue-fin tuna.
.
Thanks to 4 decades of overfishing, it has been driven to just 3% of its 1960 or pre-longlining abundance - a decline of 97% (ICCAT is the international commission that claims management authority over all tunas, marlin, swordfish and the other big fish of the Atlantic) In comparison to blue-fin,
.
Atlantic white marlin abundance has been driven to 6% of its pre-longlining abundance, and Atlantic blue marlin has been driven to 20% of its pre-longlining abundance.
.
Long lining is the current favoured method of fishing whereby set lines of over 100km are common
Yes that's over 100km of line.
Attached to it are literally thousands of baited hooks.
An estimated 1 billion hooks are set annually by the world's longline fleets.
Depending on the type of long line, buoys, floats and/or weights are used to position the line on the seabed or at the required depth in the water.
.
Of course modern radar and other aids mean that the fish have no chance, hence the continuing rapid decline in numbers
.
For a long time, the north Atlantic swordfish stock has been declining more rapidly than any other marine species.
.
It has been steadily doing so at the same rate each year for the past 20 years!
.
Destruction of this population has been meticulously documented each year for ICCAT by its scientific advisory committee.
.
Yet ICCAT has failed limit the catch of its member states sufficiently in order to produce its stated management objective - the maximum sustainable yield or MSY
.
The cause of this decline in abundance is excessive fishing pressure by commercial fishing fleets.
.
By 2000, it had grown to 4 times higher than the sustainable level or MSY .
.
Fishery managers should never allow fishing mortality to remain above the MSY level.
.
Populations of the "Large Coastals" are Down by 50 to 80%
.
The population status of most "large coastal" shark species of the U.S. Atlantic coast (39 species) is less well documented than those for Atlantic swordfish, other billfish and tunas
.
But, they appear to have declined even more severely and in a shorter period of time.
.
These include many familiar species such as hammerheads, bull, lemon, blacktip, sandbar, nurse and great white.
.
It is estimated that the large coastal shark group has declined from roughly 9-11 million fish in 1974 to an estimated 1-2 million fish in 1998 or about 30-36 percent of the population size needed to produce the maximum sustainable yield (MSY).
.
The status of the "pelagic" shark group is unknown. It includes the makos, porbeagle and blue shark.
.
OK so politically those responsible refuse or are unable to control or ban the fishing of these endangered species
And of course this is not in isolation from everything else in the world's oceans where the impact of this slaughter is not yet understood in its knock on effect
What is clear is that humans are wiping out a major source of food
Humans are destroying millions of years of evolution
Difficult to see what can be done at this late date given the lack of imagination and political willpower
Still you can always tell your children that you once saw live fish swimming in the ocean
What a mess
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