It’s the smell that hits you first. The smell, then the sound. From the wooden walkway, you can see them in their hundreds, spread across the beach.

The cows low. Their pups bleat. All feeding and breeding and fighting for territory.

Welcome to the Cape Cross Seal Reserve on Namibia’s Skeleton Coast. Just north of Swakopmund and Henties Bay, on a stretch of stark and salty desert, it is home to Namibia’s largest breeding colony of Cape fur seals.

It was established in 1969 “to protect the largest breeding colony of Cape fur seals in the world”, sings the brochure.

“Walk along the edge of the colony and learn more about these captivating creatures.”

What the brochure does not tell tourists is that early every morning for 139 days every year, groups of men will patrol this beach and two other breeding colonies like it. Six thousand bulls will be shot, and their genitals removed and shipped east as aphrodisiacs.

Some 80 000 pups will be chased down, rounded up, and beaten to death.

It starts this Sunday.

“We don’t like the seals here,” says a Henties Bay fisherman gruffly. He won’t give his name. None of them will.

Everybody in the small fishing town knows somebody employed from July to November to do the sealing, but they won’t talk. The industry bosses won’t comment either.

“They eat all the fish, you see?” explains the fisherman. “Have you been to Cape Cross? There’s thousands of them there. And the smell! The filth! There’s too many. We have to kill them or they’ll get out of control.”

It’s a commonly held belief in the town, the country, the world – seals are ravenous feeding machines. Those seals that don’t steal the fish, wreck equipment.

It’s an argument that was made as early as the 2nd century: “When the fishermen have unwittingly enclosed a seal among the fishes in their well-woven nets… it will easily break them and prove… a great grief to the hearts of the fishermen,” recorded Greek writer Oppian on Mediterranean monk seals. “(The fishermen) bring it near the land; there with trident and mighty clubs and stout spears, they smite it on the temples and kill it.”

Some 2 000 years later, only about 500 Mediterranean monk seals still exist. They are classified as highly endangered. Fishermen still want them gone.

In Namibia, the seals are killed at three sites: Cape Cross in the north, and Wolf Bay and Atlas Bay near Lüderitz in the south.

All three are breeding colonies, all three a mass of crowded and dense wildlife ready to stampede at the approach of the sealing gangs.

The pups are separated from their mothers – the sealers have no interest in either the pelts or the genitals of the cows – and rounded up into groups. Then, they are released in a haphazard single file to run the gauntlet between rows of awaiting clubbers.

What should happen next, according to international standards of the humane slaughter of animals, is a three-step killing procedure: stun the animal with a single strike or shot to the head; ensure the animal is either irreversibly unconscious or dead; and sever an artery to bleed the animal out. An outdoor abattoir.

Only, Cape fur seals don’t exactly co-operate in their own killing, making Namibian sealing inherently cruel, says Dr David Lavigne, a science advisor for the International Fund for Animal Welfare who has been researching seals for more than 40 years.

“In the case of the Namibian hunts, the animals are rounded up and herded, causing a certain amount of panic,” he explains.

Evolved to be highly mobile on land, the seals stampede, running nearly as fast as a man. The pups that cannot escape are rounded up in tight bunches. Some may suffocate and overheat before they’re even released.

When they are, they run.

For an experienced sealer, the first hits of each morning are clean strikes, clean kills. But as fatigue sets in, this ability decreases.

“These pups are fairly agile,” says Lavigne. “There’s no way to stun the animals with one blow, so the sealers end up beating the hell out of them.”

Media coverage of the sealing is banned in Namibia, but undercover footage obtained at Cape Cross in 2009 showed sealers repeatedly beating pups with no attempts to monitor them or to bleed them out immediately.

Officially, the Namibian seal slaughter is not a cull but a harvest, an independent state exerting its right to exploit its resources as it sees fit. Which is how it defines seals: as a resource to be harvested.

The government has done little to reverse the predominant thinking that the seal population must be controlled.

Instead, against a growing tide of anti-sealing activism in September, Fisheries and Marine Resources Minister Bernard Esau said: “The primary objective of seal harvesting in Namibia is to manage the seal population in relation to the carrying capacity of the entire ecosystem, in balance with the need for sustainable usage of our fish stocks.”

Esau’s statement echoed arguments in the late 1980s, when SA began contemplating an end to its own centuries of sealing.

The objectives of a harvest had become blurred with a cull.

SA’s department of environmental affairs said culling was necessary to preserve the hake fisheries. But bowing to public pressure, it placed a moratorium on the harvest in 1990.

“And then South Africa did something very strange,” says Lavigne. “It held an international workshop on the biological interactions between the seals and fisheries, resulting in numerous recommendations. And then it asked its scientists to actually implement those recommendations.”

The findings were… complicated. “They came back arguing that a cull might produce some small benefit to hake fishermen, but if so, these benefits would be much less than expected,” says Lavigne.

“What was much more likely was that because of the different species interactions, there was a higher probability that a cull would be detrimental to the fisheries.” Because a species cannot be treated in isolation from its ecosystem.

Marine systems have no defined boundaries and are connected, says Dr Samantha Petersen, manager of the WWF’s sustainable fisheries programme.

“Seals are top predators, which have a very stabilising effect on an ecosystem. Put simply, remove a predator and the prey responds.”

In the Benguela Current Large Marine Ecosystem – which extends about 30º in latitude around SA’s south-western coastline, along Namibia and into southern Angola, and includes seals, hake, monkfish, blue sharks, and various seabirds, while dealing with the consequences of fishing, mining and global climate change – scientists can only predict so much, says Petersen.

Even when the intricacies of the food web are considered, unforeseen natural events can throw out the entire system.

In 1994 and 1995, biologists noticed an unusually high mortality rate among Namibia’s Cape fur seals. Thousands of seals of all ages were washing up on beaches, starved to death.

Some saw it as evidence that the seals were emptying the sea of their own food source, that they had “exceeded by far the carrying capacity of the environment”, as the Namibian Ministry of Foreign Affairs said at the time. “It must surely be agreed, therefore, that it is more humane to curb the unrestrained seal population to a level where they can be sustained by the environment.”

The real cause? Anomalous environmental events in the Namibian waters.

First, low oxygen in the shelf waters off Namibia, lasting longer and spreading further than usual low oxygen events that affect the northern Benguela. Soon after, a strong Benguela Niño event, whereby warm waters infiltrated the usually cold Namibian shelf.

Both had the same effect: mass mortalities, recruitment failure and migration of fish and their predators. A third of Namibia’s Cape fur seals died of starvation. Another two seals mass die-offs have since been publicly acknowledged, one in 2000 and another in 2006.

Henties Bay locals claim to have seen many seal carcasses littering the beaches this season, as well, though the Ministry of Fisheries and Marine Resources has made no official statement.

Results of the annual December census, used to calculate the harvesting quotas, have not been released since the last mass die-off in 2006 – not even to the Namibian ombudsman, who has been investigating activists’ claims that the seal harvest is not being conducted sustainably.

The ministry says it uses the most practical methods available, challenging critics to come up with alternatives.

Activists have refused to help brainstorm better ways of killing an animal they argue does not have to die.

“‘Harvest’ is simply a euphemism for ‘hunt’, chosen by some people to make it sound like we’re picking potatoes,” says Lavigne. “We’re not dealing with agricultural crops. These are wild animals.

“And even ‘hunt’ is the wrong word. It involves some element of fair chase. But the way it’s conducted, this is no hunt. It’s a slaughter.”