A Long Forgotten Missing Piece Of The Northwest Atlantic Ecosystem Has Present Day Impacts
The renowned astrophysicist Neil DeGrasse Tyson has said "One of the great challenges in this world, is knowing enough about a subject to think that you are right, but not enough about the subject to know you're wrong". I love this quote because it challenges each of us to inform ourselves to the greatest possible extent about those things for which we care most deeply, while constantly being open to new knowledge or discoveries, which may have the power to change our perspective. In my February article addressing the complex moral and ethical questions raised by the annual Atlantic Canada Seal Hunt, I was highly critical of the many fisheries managers and lobbyists, both in the Canadian Maritime Provinces and New England, who contend that populations of native seal species have grown far beyond sustainable levels, and are doing serious damage to the marine ecosystem. I even went so far as to state that these industry representatives lacked even a basic understanding of the ocean food web. While I still believe their statements relating to the "danger" seals present to our fisheries are extreme and alarmist, and they are not acknowledging the great benefits seals bring as top predators, I was missing a piece of the puzzle. An obscure and largely forgotten piece, buried deep in history, that sheds some light on the strongly divergent perspectives on the effect of seals.
The second half of the 18th Century was a time of great upheaval and suffering in Colonial North America, first with the French And Indian War, and then The American Revolution, so few people probably noticed the killing of the last Maritime Atlantic Walrus. When the first European settlers arrived in Canada in the 1500's, there were at least 100,000 of these massive creatures, living in huge herds ranging from Les-Iles-De-La-Madeleine and Prince Edward Island in the Gulf Of Saint Lawrence, to the coastal islands off Nova Scotia, including remote Sable Island. Sable Island is often called the "Graveyard of the Atlantic", due to its many shipwrecks, but this is also where scientists have discovered skulls of this unique subspecies of walrus. They have been able to piece together the life history of this imposing creature, tragically driven to extinction by the ivory and marine oil trades. Like their Arctic relatives, these massive animals weighed up to 1500 kilograms (3307 pounds), consumed a whopping 6% of their weight daily (90 kgs, 198 lbs) in food, and were an essential "keystone" species, due to the billowing clouds of sediment they stirred up from the ocean floor, during their regular searches for clams and other invertebrate meals. The nutrients from this sediment provided vital nourishment to the phytoplankton which form the foundation of the entire marine food web, a service the now thankfully largely protected walruses of the North still provide today.
While walruses feed primarily on invertebrates, and for some reason have little interest in fish, large males in particular use their powerful 3 foot long tusks to hunt seals, and sometimes even young Beluga Whales and Narwhals. And there is no better place in the world for a seal meat lover than Sable Island. Each winter, an awesome wave of over 400,000 Grey Seals (an estimated 75% of the entire North American population), arrives on this small island 290 kilometers (180 miles) southeast of Nova Scotia, where the majority of females give birth to pups. After nursing their babies intensively for approximately 3 weeks, the mothers abruptly abandon them to mate with the eagerly awaiting males, and together they soon head back to sea. As with Harp Seals, their close relatives to the north, the newly weaned pups must fend for themselves, while molting their neonatal lanugo fur and learning to swim and forage for food, living off the nourishment their mothers have given them, via incredibly rich milk with the consistency of ice cream. These chubby and lovable babies were also an essential food source for the Maritime Walruses of Sable Island, and everywhere their ranges overlapped.
On the afternoon of Saturday, September 15, 2018, tragedy struck the small seaside town of Truro, Massachusetts, when 26-year-old Arthur Medici died from injuries inflicted by a Great White Shark, which attacked him while he was surfboarding a little ways offshore. And on Monday, July 27, 2020, 63-year-old Julie Dimperio Holowach was wading approximately 18 meters (60 feet) from the beach in Harpswell, Maine, when a Great White Shark struck her with such force, that she quickly died at the scene. In both of these horrific incidents, marine biologists have concluded the sharks almost certainly mistook the human being for a Grey Seal, one of their key food sources. As recently as the 1980's, there were virtually no Grey Seals in New England, and only relatively small populations in the Maritime Provinces, a result of massive hunts similar to the ones that drove the Maritime Walruses to extinction two centuries earlier. But in the 1970's and 1980's both The United States and Canada banned almost all killing of Grey Seals, to allow the necessary population recovery that would prevent the tragic extinction of another precious animal. And recover the population has! The well adapted Grey Seals now number over 500,000, with large herds frequently "commuting" from Sable Island down the coast, to haulout sites in Maine, Massachusetts, Rhode Island, and New York, in a constant quest to satisfy their voracious appetite for Sand Lance, Atlantic Cod, and many other aquatic species. Their numbers have also grown greatly on islands in the southern Gulf of Saint Lawrence, such as Prince Edward Island and Les-Iles-De-La-Madeleine. And wherever they go, the now similarly legally protected Great White Sharks, who previously hunted fish far from shore, come in the hope of enjoying their favorite meal.
Completely understandably, the return of the Grey Seals has sparked great concern in coastal communities throughout the Northwest Atlantic states and provinces. Clearly the concurrent return of the Great White Sharks, who despite their keen senses of sight and smell, and amazing ability to detect the tiny electromagnetic fields given off by all living things, occasionally mistake us for our marine mammal relatives, is the most urgent problem. But it certainly is not insurmountable, as shark attacks can be avoided by installing sonar receiver systems on popular beaches, which detect the high pitched noises emitted by tagged sharks, and alert swimmers when danger is approaching. And the great beauty of the ocean is sure to continue drawing visitors from all over the world, in some cases to observe wildlife such as whales, dolphins, seals and shore birds. A more complex challenge than the attraction of sharks, is calculating and humanely mitigating Grey Seals impact on valuable Atlantic Cod stocks, that are the backbone of so many regional fisheries. In fact, many fishermen welcome the presence of the Great Whites, in the hopes they will balance the "explosion" of seals, as is it is commonly referred to in the fishing community.
This is where the effect of the tragic extirpation of the Maritime Walrus, comes into full realization. If the walruses were thriving today, as the seals and sharks are, we could be certain beyond a reasonable doubt, that the marine ecosystem is largely balanced. But we cannot draw such a conclusion when one of the three major predatory "players" has been absent so long, they are scarcely remembered. And given the lack of technology and consistent record keeping in the era when the walruses were present, we are unable to accurately calculate their effect at all. The southern Gulf of Saint Lawrence, former home of so many walruses and a favorite feasting ground for seals, is probably the region where concerns of ecological imbalance runs the deepest. Fish biologist Doug Swain of the Canadian Department of Fisheries and Oceans calculates the current Atlantic Cod population there is only 5% of what is was in the 1980's, when the Grey Seal population was still very low, and he expects the current precipitous decline to continue, with extirpation occurring within a few decades. Yet Dr. Swain does not advocate any seal culls or even non-lethal "birth control" measures, as Grey Seals are opportunistic feeders who also consume large numbers of cod predators, including forage fish like Capelin, which gobble up huge numbers of cod eggs, and a small shark called a Spiny Dogfish, which preys on adult fish. And Joe Roman, a conservation biologist at The University of Vermont, maintains that the massive amount of feces generated by seal herds, greatly stimulates the growth of phytoplankton wherever the seals go, leading to both increased ecosystem biomass and biodiversity in these areas. Perhaps the seals are filling at least part of the vital "keystone" role the walruses played so long ago.
The dramatic and rapidly unfolding changes occurring in the Northwest Atlantic, caused by the long past elimination of the Maritime Atlantic Walrus, and the present powerful resurgence of the Grey Seal and the Great White Shark, can neither be ignored nor fully understood. My heart goes out to both the friends and families of the shark attack victims, and the fishermen who are seeing the supply of their most valuable catch dwindle towards nothing in some cases. Add to that the myriad effects of a rapidly warming planet, and it becomes abundantly clear how frightening and uncertain our current situation is. Yet even though learning about the walruses has made me far more sympathetic to the deep concerns of fisheries regarding the seals, and so many others regarding the sharks, I still do not believe we should take any retaliatory action against either species. Killing animals, or even controlling their numbers, in the hopes of creating some sort of "balance", is almost never the right solution, especially in the vast and delicate marine world, about which we still have so much to learn. No species should endure the same fate as the Maritime Walrus. In so far as there is a solution, it is abiding by the method we must always apply to utilizing natural resources-respect, appreciate, and only take what we need to survive. Even though these guidelines can be interpreted in multiple different ways, the fundamental overarching principle of letting nature balance itself, is what matters. To quote another famous scientist, the Italian theoretical physicist Carlo Rovelli, "Nature is our home, and in nature we are at home".