How much fish are grey seals eating?
....Infrequently Asked Questions
seems to be the single most frequently asked question about grey seals. For some
people, this is the only question.
(...stating that "seals eat 3,000 tons of cod, compared to a total cod biomass of 8,800 tons," is about as meaningful as stating that "1.5 liters of blood flow into the lungs every minute, compared to a total body blood volume of 6 liters"...both are merely examples of finely balanced natural cycles, of healthy closed loops. And both involve the active maintenance of healthy oxygen levels.)
No. There is exactly no evidence to support the general assumption that fewer seals will mean more fish. Human intuition on aquatic questions has a proven, notorious tendency to be dead wrong. (Remember the cod?) It bears consideration that the peak historical abundance of seals (say, five centuries ago) coincided with the peak historical abundance of fish, and that it seems these proportions had been previously maintained for many millions of years. Did the seals not only eat the fish but somehow invigorate the ecosystem that produced them? GSCS strongly promotes the close examination of all aspects of natural seal ecology before the implementation of any new seal hunting.
GSCS is genuinely worried about the future of seals.
Changes in Atlantic Canadian seals have been noted recently, in their biology and in their behaviour, which suggest that seals are also responding to broad shifts occurring in the ocean. The nature of these trends, if they continue, may soon threaten the continued survival of seals (whether we hunt them or not). The assumption that any marine animal population will continue to replace its numbers in the future as it did in the past cannot be justified today. The negative shift in zooplankton – in fish food – plus the broad decline in fish growth, promises to “naturally” curtail seal numbers, and possibly in the very near future.
Seals have been observed recently (by scientists) to be in lowered physical condition (less fat) and to be experiencing a lower pregnancy rate than they did a few decades ago. These signals suggest a lowering of the food availability for seals. Some will point out that this pattern means that seal numbers have reached the natural “carrying capacity” of the ecosystem (that no more can be supported), and this argument has been advanced as a reason to lower the numbers of seals by hunting. Some claim that seal numbers in Atlantic Canada are now at “historic highs,” but this is a woefully short-sighted view of “history.”
All seal species together in Atlantic Canada might number 6 million animals today, whereas, 500 years ago when the first Europeans arrived, there were an estimated 40 million seals living here, at least. The food base that “carried” the seals of 500 years ago – the small fish produced in the sea – supported not only the 40 million seals, but also untold numbers of other predators that competed for the same prey. Hundreds of thousands of fish-eating whales, fantastic numbers of giant seabirds now extinct (the great auk), and unimaginable numbers of large fish, fed on the very same food supply that supported the seals. The tonnage of small fish consumed annually by this predator group greatly outweighed human fisheries, then or now.
The near total removal of whales, large seabirds, and large fish from the ocean should – according to the way the “math” has usually been done on these things – have left a huge glut of small fish available to the reduced number of predators that remained. Natural fish predators should all be fat and happy today. Six million seals would be barely able to put a dent in their food supply today if it were being produced at the rate of 500 years ago. Therefore, signs of hunger in a mere 6 million seals today should alert us to the dramatic decline in the PRODUCTION of their small fish prey…and we should be turning our attention to finding out WHY this has happened. (Hint: that “math” was based on one fatal faulty assumption.)
For an “intelligent” species, humans can be incredibly obtuse. Those who are bothered by the lack of fish today reckon that “predator removal” will cause fish to appear in the ocean in greater numbers. But our grand ocean “predator removal” experiment has been ongoing for centuries. In fact, it is nearing total completion…the point where humans will be the only significant fish predators left…but overwhelming evidence suggests that the overall project has backfired stupendously. Rather than being left with massive fish production for exclusive human use, the extermination of natural fish predators has mysteriously coincided with an astonishing decline in fish numbers. Very few fish are left in Atlantic Canadian waters, and they appear to be suffering WITH the seals (rather than FROM the seals) because they also do not appear to be getting enough to eat.
Seal populations in poor condition can decline rapidly. Outbreaks of viral illnesses have decimated European seal populations in recent years. The Nova Scotian harbour seal population on Sable Island has recently nose-dived. These harbour seals went from steadily increasing their numbers throughout the 1980s, to unexpectedly plummeting to near zero in recent years.
The opinion that seals are not “endangered” today comes only from those who are insensitive to the “danger” signals. Seals are only secure as long as they have fish to eat…but fish are increasingly disappearing, and worse, the smaller food for fish appears to be disappearing too.
Much lip service in the “management of marine resources” is given today to using a comprehensive “ecosystem approach” to scientific assessments and decision-making. But it is not done, because people are reluctant to face the truth. An honest “ecosystem assessment” in Atlantic Canada at this time would acknowledge that virtually all larger marine animal life is “endangered” by the unexplained decline in plankton production. And prudence would call for a halt to the killing of all natural predators of fish, because it looks as if they are critical players in the maintenance of the fertility of the ocean system itself.
“Only two things are infinite, the universe and human stupidity, and I’m not
sure about the universe…”
Finally, grey seals are “endangered” in Nova Scotia today by a complete lack of protective legislation. There are legislated limits on the killing of most other wildlife, but none for the Nova Scotian seals. The official status of seals appears to be that of a form of pestilence that interferes with fisheries…in a class, one supposes, with something like a potato blight. The only form of quasi-“protection” that the grey seal (and the harbour seal) have ever enjoyed in Nova Scotia has been the removal in the 1980s of a bounty that was on their heads. One monetary incentive to kill seals was merely removed as the official seal extermination agenda temporarily slowed. But this was a far cry from protection.
Recent media reports of a “proposed grey seal hunt” aimed at reducing Nova Scotia grey seal numbers by half, might suggest to some readers that this particular “hunt” has not yet been started, and that perhaps fishermen are awaiting official approval to kill the grey seals. That is not the case. In practice today, many fishermen routinely shoot seals on sight, of any species, whether they are near fishing gear or not, and seals are also caught and drowned in sunken, baited leg-hold traps.
There are rules in Canada for killing ice seals – the harps and hoods that are killed in the annual spring seal hunt in Newfoundland and off Prince Edward Island – legal guidelines that aim to ensure that ice seals are killed “humanely” (which resulted only from the glare of international public disapproval). However, at this time “anything goes” in the killing of Nova Scotian grey and harbour seals. If fishermen decide to hunt down and kill or maim every seal living in Nova Scotian waters, there is at present no reason to think that the Department of Fisheries and Oceans or the Royal Canadian Mounted Police will bat an eye.
(In contrast, just south of Nova Scotia, in the United States, intentionally injuring a seal violates the Marine Mammal Protection Act and is punishable by fines of up to $10,000 and jail time. Weirdly, Canada officially imagines that it is an “international leader” in marine management…but I digress.)
In theory, yes, a sustainable seal harvest would be acceptable to GSCS. However, this would likely only ever be feasible at a subsistence level, as sealing was once done by aboriginal people.
Today, under the worrisome scenario of broad negative shifts in ocean productivity, and great scientific uncertainty, a “sustainable” grey seal harvest cannot be implemented in Nova Scotia. Even DFO admits that it does not have the necessary information to “calculate” a sustainable grey seal yield (…even presuming that DFO’s calculation methods were somehow reliable – which they are not, since the seal math is only the same flawed “single species” math that continues to be applied to the fish stocks…)
"Given the marked changes observed in the Gulf of St. Lawrence since the last (grey seal) population survey and the absence of recent information from Sable Island, no estimates of replacements yield can be calculated." - Atlantic Seal Hunt Stock Prospects for 2003-2005, DFO
The grey seal population in the Gulf of St. Lawrence appears to be in decline. Will DFO find the integrity to instruct the Nova Scotia fishermen to hold their fire?
Below is an excerpt from “Canada’s Oceans Act,” a federal law enacted in 1997:
promotes the understanding of oceans, ocean processes, marine resources
and marine ecosystems to foster the sustainable development of the oceans and
The federal government (DFO) has the responsibility for the “stewardship” of all marine animal life in Canada. However, “stewardship” means “the careful and responsible management of something entrusted to one’s care.” This “stewardship” concept has never been applied to grey seals in the past. Far from it. DFO’s past management approach to grey seals has amounted only to the implementation of programs aimed at their deliberate extermination from inshore waters. Grey seals have been viewed simply as vermin by the government and the fishing industry, and DFO has issued a long stream of (mis)information in the media over the years that has quite effectively brainwashed the public into accepting this view. One wonders whether the recent efforts to increase the sophistication of DFO’s techniques - all the repetition of the new “ecosystem approach” and “precautionary approach” mantras – might have brought about any change in their fundamental approach to the grey seal.
Sadly, GSCS doubts it.
of humane: "marked by compassion, sympathy, or consideration for humans or
animals" (Webster's dictionnary)
Yes. However, this right does not over-ride the accompanying responsibility: a legal obligation for those who extract common public resources to avoid causing permanent damage to either the resources or to the ecosystem that produced them. Unfortunately, this places many people involved in the fishing industry in a difficult position today.
(Questions 7 and 8 are discussed in detail in the article Grey Seal Hunt 2004 by Debbie MacKenzie)