Of fishermen and the fish they will not be able to catch anymore
Fishing as a job and a hobby appear thousands of years ago. It is probably one of the oldest professions in the whole world. And still, it plays the major role in the economy of many countries around the world. But the fishing is not the same it was back in the day. The humankind made a long way from fish forks and spears to trawlers and purse seiners. However, mastering the craft of fishing resulted in depleted fish stocks. Some fish populations and even species have vanished from the Earth, and they still do right before our eyes.
In the very beginning of the XX century, the herring stocks between three islands – Hokkaido, Honshu, and Sakhalin – were considered inexhaustible. Fishery scientists were scrutinizing the fish thoroughly from all sides, including its behavioral characteristics and feeding preferences. The fish received high importance in the context of plan economy. In the most successful fishing seasons, Russian and Japanese fishermen caught as much as a million tons. No other herring population in the Russian Far East had ever come even close to these numbers. But the years of prosperity ended suddenly and painfully for both fisheries and herring population.
In just a couple of decades in the middle of the XX century, the takes first became ten times lower, and then hundred times lower than they were in 1930’s. Some scientists say, Kuroshio, the Japan Current, was the trigger for the awful changes to come. The current changed its way, thus changing the oceanographic situation on the herring’s spawning ground. The drop in the number of individual herring was so sudden that neither science nor fisheries could adapt. Fishing in same amounts, fishermen started to take immature species, undermining stocks’ sustainability. Thus, even after Kuroshio returned to its normal state, the Sakhalin-Hokkaido herring population was not able to recover.
However, another group of fishery specialists denies any decisive influence of ocean currents. They call human unsustainable activity on herring’s spawning ground the major cause of all negative trends. Coastal development and pollution of shallow waters near the sea shore demonstrated negative trends right away but no one was eager to spot them before the tragedy was inescapable. Fishing for immature species was a final punch on the knocked-out population.
Japanese fishermen refused to admit that Sakhalin-Hokkaido herring population had ever existed in the first place. They preferred to divide it in two according to its origin either in Russian or in Japanese part of the sea. Japanese fishermen continued to fish for herring at full throttle. Thus, even several fertile herring generations were taken right away and could not influence the generally dire state anyhow.
Fishing for herring in this region of the Pacific Ocean is still going on. An average take is two thousand tons. And although fishery scientists admit that there is no any noticeable difference between the herring from Hokkaido and one from Sakhalin. The joint population doesn’t exist anymore.
Salmon in the Aral Sea appeared in ancient times. It came through rivers from the Caspian Sea. These species are far from being called the largest salmon – its average weight is 13 kilograms. As all anadromous species do, the Aral salmon’s feeding grounds were located in the salty waters of the sea, which technically was a huge lake, the fourth in the world. In November, the fish swam back to spawning grounds in the fresh water of the home rivers. Some of the salmon made this way four times in their lives.
The Aral salmon population was very small due to its biological characteristics: spawning in the coldest time of the year, longtime roe ripening. But the decline of the population was caused only and entirely by humans. It is no secret that the result of active consuming of water from the Amudaria and Syrdaria Rivers was that the sea grew rapidly shallow and eventually almost fully disappeared. Since the end of the XX century, there were no recorded data of Aral salmon species caught. This gives solid reasons to think that this kind of salmon is extinct.
Another representative of the salmonids is muksun. It is valuable fish for commercial fishing. Muksun can be found in the rivers and lakes of Siberia, in fresh water inshore waters of the Arctic Ocean. There is a recorded case when a 13 kilogram muksun was harvested. However, from today’s perspective it looks more like a fairy tale because now muksun’s ordinary weight is from one to two kilograms.
Historians say, that hundred years ago. The Tom’ River was so full of muksun that people who lived on the banks of the river were called “muksun-niks” which would mean something like “muksun people”. However, today muksun is a threatened species in Russia.
In Taymyr, in the northern part of Krasnoyarsk krai, the muksun population is at the edge of extinction. The same dire state is in Tomsk and Tyumen regions. In 2014, fishing for muksun was limited there, In 2017, fishing for muksun was completely banned for the whole West-Siberian basin. Scientists try to restore the population through hatcheries. However, the situation didn’t get any better in last three years.
There are two main causes of the poor condition of this fish stocks. The first one is poaching which is considered to be two times higher than the legal harvest. The second one is the activity of oil producers.
Nelma is a close relative to muksun. They shared habitat as well as radical population decline trends. Nelma is one of the salmonids, although it is much bigger than muksun: it can be a meter and a half long and up to 50 kilograms weight. Medium weight of nelma is from five to ten kilograms.
Fishing for nelma is prohibited in all southern and central Siberian regions. Nelma fisheries were shut down in Tyumen region, including Yamalo-Nentsky and Khanty-Mansiysky autonomous districts with the rivers Tobol, Tavda, Tura, Iset', Ishim, and Irtysh in 2015. Two years later, the official Fishery Regulations banned fishing for nelma in Tomsk region permanently until the population gets better. Nelma can live up to 22 years; thus fishery scientists insist, that it would take natural mechanisms at least two times as much to restore the population.
Nelma is very selective while choosing a spawning ground. It prefers deep streams and avoids shallow waters and riffles. High-volume takes and habitat fragmentation put these species on the edge of extinction.
This, however, is not the full list of all vulnerable species. WWF-Russia has told many times about critical conditions of the sturgeon population in the Caspian Sea, omul in Baikal Lake, king salmon in the western Kamchatka.In general, there are three particular factors which cause a severe negative impact on fish stocks:
- overfishing during legal commercial harvesting;
- human impact and activity which destroys habitats of vulnerable species and marine and river ecosystems.
WWF reminds that the Fisherman's Day is not only a cause of celebration and fishermen recognition but also a Day counteractions to exhausting and unsustainable fishing.