Can the most endangered group of species on the planet make a comeback?

June 19, 2019 by Rory Moore

I stood on the bank of the Wolf river in Shawano, Wisconsin, midwestern United States. The area was rural and nondescript. The frigid air was biting as the sun was yet to break through the early morning fog.

I was on a mission. I had heard that this was perhaps the only place in the world where conservationists had successfully restored sturgeon populations. Sturgeon are the most Critically Endangered group of species in the world, according to the IUCN Red List. They shared the planet with dinosaurs but, relatively recently, humans have been less good at sharing. In a careless robbery of natural resources, we have dammed rivers, laid fishing nets and polluted lakes. On top of all of this destruction, we hunted the few remaining fish for their caviar and meat. The sturgeon didn’t stand a chance.

I work in the Caspian Sea region, trying to bring back six species of sturgeon from the brink of extinction. I also had an idea of ‘rewilding’ European sturgeon into rivers in the UK (where they used to reside) but I needed to understand how the Americans had done it, against all odds. It is also worth noting at this point that I had spent my summers on a sturgeon farm in California and had much experience with these fish, but I had never in my 37 years seen a live, wild sturgeon. They are that rare.

Sturgeon near the Shawano dam

Directly in front of me stood a paper mill and upstream a hydroelectric dam that had been servicing the mill since the late 1800s. The river water was copper-brown, cold and uninviting but something was stirring beneath the frothy surface. As I squinted through my Polaroids, I made out the shape of a large dark fish, perhaps 5 feet in length – almost shark-like. Then another and another and all of a sudden, I realised that I was witnessing something that I had only dreamed of. The sturgeon had arrived to spawn! Hundreds of huge fish, perhaps a thousand, had reached the Shawano dam and could swim no further. Their heads literally bumped against the dam as they instinctively tried to get as far up river as possible.

The Shawano dam is the now end point of the great annual sturgeon migration and, for a couple of days a year, the prehistoric fish do what they must do for the species to survive. The Wisconsin Department of Natural Resources (DNR) has meticulously created an artificial spawning ground in front of the dam: gravel-rock beds of a particular size, on which the fish can lay their eggs (otherwise known as caviar). Several male sturgeon rubbed up against the larger female, coaxing her to deposit her eggs and as she did so, they fertilised them. Two weeks later the eggs would hatch and the fry would make the 130 mile journey back to Lake Winnebago. Only the very lucky few would survive to return to the dam to spawn when they reached adulthood, almost 20 years later.

The comeback of the lake sturgeon is one of nature’s great love stories: a story of symbiosis between man and fish. 12 miles upriver from the Shawano Dam lies the Keshena falls, the ancestral spawning grounds for sturgeon. The falls lie on land lived on by the Menominee Tribe, once led by great chief, Oshkosh. The Menominee people have always felt close to the sturgeon. Before the dams, they would celebrate the arrival of the fish each year, spearing a select few from the river for their sustenance. Since the dams, the Menominee have lost the sturgeon but restoration efforts are underway and each spring the tribe still drums the ancient drum beat on the riverbank, mimicking the sounds of spawning fish and calling them home.

Exactly 142 miles downstream, the ice is melting on Lake Winnebago. In winter months it is frozen thick and for just one week the lucky possessors of a sturgeon spearing licence (won by lottery) head out onto the frozen plains to hunt. The process of spearing a sturgeon is fairly straightforward: one sits in a small hut for a week looking through a hole in the ice, waiting with spear-in-hand for a fish to pass underneath, perhaps attracted by a hand-carved lure or decoy. However, the rules are strict, the weather harsh and catches are few and far between. It took seasoned sturgeon spearer Harry Kachur 22 years on the ice before he speared his first sturgeon. “I’ve not had a lot of luck out there on the ice, is what it amounts to” he said like a true Winconsiner (wisz-CAHN-sinerr).

Crowds of people can gather to watch the sturgeon spawning

The revenue raised from selling the spearing licenses goes directly back into conservation of the sturgeon and locals believe that the seasonal, managed hunt maintains an affinity between the people of Wisconsin and their anadromous* neighbour.

*An anadromous fish is born in fresh water, spends most of its life in the sea and returns to fresh water to spawn. Freshwater eels, for example, are the other way around (catadromous).

By mid-morning, two dozen or so of the townsfolk had come down to watch the sturgeon spawning. Children were dancing around on the bank in excitement, cameras were out and a film crew had joined to document the action. I saw a group of men and women holding nets on the opposite bank so I wandered over the dam. I was greeted by Ryan Koenigs, a fisheries biologist with the DNR. Ryan was sitting on the head of a sturgeon measuring 62.5 inches in length. I knew this because there was a large ruler lying next to the writhing fish. As the fish was flipped onto her back, a jet of creamy-brown eggs squirted out of her abdomen and were skilfully caught in a beaker. Ryan proceeded to massage the fish’s belly encouraging more eggs to flow. We then took the eggs to a makeshift laboratory on the riverbank to fertilise and mix them. Ryan explained that each year his team artificially rear a certain number of fish, which are then released into other nearby river systems to restore resident populations. The success was spreading.

Eggs being collected from a female sturgeon

I talked to Ryan about my experiences in the Caspian and the uphill struggle against illegal poaching and river habitat destruction, not to mention the lack of an existing viable breeding population. Ryan described a time in Wisconsin’s history when the lake sturgeon were persecuted to the point of collapse. Post-industrial revolution, dams were built, spawning grounds lost and in 1885 records show that 8.6 million tons of sturgeon were taken from the Great Lakes. They were slaughtered, burned as fuel for steamships, their swim bladders removed for wine making and their caviar sent to Europe under the false label of ‘Russian caviar’. By the late 1920s, the fish faced extinction.

I compared this story to the plight of Caspian sturgeon, which were actually doing relatively well in the 1920s. The great sturgeon spawning rivers in the region (Volga, Ural and Kura) were still undammed and poaching would become a major problem after the collapse of the Soviet Union many years later. Beluga and other species of sturgeon were certainly being harvested in the Caspian, but extinction was half a century away. It was almost reassuring that the lake sturgeon populations had once ‘hit bottom’ as they had presently in the Caspian and had recovered so quickly. Ryan and I discussed the success of the Wolf river project. Essentially, community-led conservation backed by good science and strong regulation had assured the recovery of the lake sturgeon.

 

A sturgeon being measured

‘Sturgeon for Tomorrow’ is a local volunteer group which patrols the rivers during the spawning season and shares information about movements of the fish. This not only informs Ryan and the enforcement agencies about the whereabouts and safety of the sturgeon but also further bonds the community with the fish that they have become so proud of. The patrol is so popular that there is a waiting list to sign up each year. Ryan thought it unlikely that any fish were poached at all these days.

As a fish biologist, Ryan had come up through the ranks of sturgeon experts, learning his trade from his professors and predecessors at the DNR. He knew the ecology, anatomy and history of these fish like no one else. He knew exactly where the fish liked to spawn: how fast the currents should be, ideal water temperature, size and quality of gravel, acceptable levels of pollution. He could spot a female fish among a shoal of jostling males and insert a tracking tag in a flash. His team was dedicated and well-informed. These sturgeon were in good hands.

I realised that the restoration of a sturgeon population was not impossible (you will forgive me if I was starting to wonder as I walked among hundreds of sturgeon carcasses in the black market in Baku, Azerbaijan) and that it was not rocket science. In fact, on the Wolf river it was quite simple:

  • suitable spawning areas were restored beneath upper-river dams;
  • healthy, genetically diverse fish were reintroduced into the river and monitored;
  • enforcement was a collaboration between communities and enforcement agencies, ensuring local buy-in;
  • a flow of funding for conservation was secured through an artisanal well-managed, sustainable fishery.

The benefits of the project reach beyond the sturgeon.  An economic study conducted in the early 2000s estimated that at least $350,000 came into the local economies of New London, Shiocton and Shawano each spawning event, and locals are confident that number has gone up substantially in recent years.  The restoration of spawning grounds has prevented river bank erosion and, in addition to sturgeon, the rock beds provide habitat for other species, most notably smallmouth bass and flathead catfish.

I returned to London full of optimism and will take my stories with me to Azerbaijan this summer. Ryan has offered his expertise and may join us in the Caspian to replicate the successes of Wolf river. Perhaps one day, 20 years from now, we will stand on the banks of the Kura river and watch beluga sturgeon spawn before the mighty Mingecevir dam.