An ever-growing part of the fish that we eat, such as Salmon, is being raised in fish hatcheries, as opposed to acquiring these fish the traditional way – by fishing them from the wild. Let’s discuss some species of fish that are raised in hatcheries, including Salmon, and how they are raised in these hatcheries.
As time moves on, and our population continues to grow, we Americans consume more and more fish, putting increased strain on the wild fisheries that formerly provided for our fish consumption. This has caused the population of fish stock in our wild fisheries to become increasingly depleted, being consumed more quickly than their numbers can increase by natural reproduction. In order to help solve this problem, society has gone about two different solutions, both of which involve using fish hatcheries. One of those solutions is to grow fish in fish hatcheries, and when they get old enough, introduce them into the wild, where that species of fish’s wild population normally resides, in the hopes that this introduced hatchery fish can offset the decreasing wild population numbers, helping to increase their numbers overall, and get the wild fish stocks to become high again, perhaps to the point where their reproduction rates are high enough to offset capture numbers by fishing crews. The other solution is to increasingly provide for our own fish consumption by using fish grown entirely in fish farms to adulthood in ponds entirely in those fish farms, who never see the wild, thus reducing our dependency on wild fish stocks.
The fish hatchery process takes place like this: first, a worker at the hatchery will find the female fish, and strip them of their eggs into a bowl; then male sperm is added to the mixture in order to allow the eggs to become fertilized; then the fertilized eggs are protected, much as they are by their mother in real life, until they hatch and become baby fish, known as fry; the fry are put in a pond to grow to maturity; the mature fish are then harvested and brought to market, or are placed into the wild, where they mix with wild fish of the same species and increase their general population. One of the most important things to remember is that when the fry are put into an ocean, lake, or river, it has to be in a place where the water temperature is just right, in the right place where wild stocks are currently at, and the timing has to be right, or the escapement will be way off – escapement is a educated calculation as to how many fish return upstream. It can be quite disappointing if 50,000 juvenile fish are released into a stream, and the following year’s escapement turns out to be less than 5,000 – something happened to all those fish, and you need to discover why.
The U.S. Fish and Wildlife Service, which is part of the Department of the Interior, has developed a National Fish Hatchery System, which has been in use since 1871. Fish Hatcheries, under the auspices of this branch of the U.S. government, are intended not to provide commercial fish that is consumed by people, but are instead intended to resupply fish stocks in natural environments whose population numbers have dropped, in the hopes that by increasing the supply of fish in the wild, they will reduce the chances of that fish population being depleted to the point of extinction by our overfishing (read more here). They hope that they can protect our aquatic resources, in this case fish, by going this route, acting in a conservationist way against our society at large. This agency works with other federal agencies, as well as state resource agencies, tribal governments, and private organizations, and they’ve helped to recover populations of several species of fish, allowing them to be taken off the endangered species list – this includes Great Lakes lake trout, Atlantic and Pacific Salmon, Atlantic Coast striped bass, sockeye, and chum, as well as a few others. This has allowed fishing crews in the Atlantic and Pacific Oceans, as well as in the Great Lakes, to have stock to gather for the market. It has also allowed for anglers, such as in the Great Lakes, or on rivers and streams out west, to be able to practice recreational fishing, which helps to bring money to the economy.
While many fish are grown in hatcheries to be released into the wild to help improve fish species stock numbers, many fish are raised, outside of the wild, in fish farms, which use fish hatcheries to help grow large populations of fish stocks for human consumption quickly, allowing us to grow more fish than would otherwise occur under wild, or natural, circumstances. It is hoped that by taking care of our fish consumption demands, we can reduce the strain on wild fish populations, helping to alleviate the risk of over-depleting that wild stock. This includes many different types of fish, including catfish, bass, salmon, carp, tilapia, and cod. Of course, sometimes the fish that grow in fish farms, that come from the fish hatcheries, are fed fishmeal from wild fish stocks, since they are carnivorous by nature, and end up consuming more wild fish, in terms of pounds, than they turn out as hatchery fish in the end, thereby negating the whole reason for growing fish in fish farms and their hatcheries, as opposed to just getting them from the wild.
One of the benefits to growing our consumption supply of fish in hatcheries, as opposed to getting them from the wild, is that in the wild, only 2% of fish eggs make it through fertilization, whereas in fish hatcheries, upwards of 80% of fish eggs make it to fertilization, allowing the fish populations in hatcheries to grow much faster than fish populations in the wild. The hatcheries offer a protection from predators which they don’t get if in the wild, although there are some who would argue that this is not good for nature, but that will be discussed in the next paragraph. All that is needed to grow large numbers of fish in hatcheries is the proper water type for the fish to be grown, plenty of oxygen, the right temperature and food sources.
There is an argument that by introducing hatchery fish to the wild this actually weakens the genetic strength of that particular species, as in the wild, the fish with the best genetics translating into speed, strength, agility, and so forth, are the ones that actually make it – a counter argument is that when juvenile fish from the hatcheries are released into the wild, the majority of them don’t make it, meaning that only those which are the strongest, fastest, most agile, survive. Another problem is the fact that sometimes fish with infestations, such as sea lice, are introduced into the wild, where they infect, and kill off, the wild version of their species, leading to greatly reduced proportional rates of wild fish (read more here).
Washington, Oregon, and British Columbia have fish hatcheries in order to replenish the supply of Salmon and Chinook, Sockeye, Chum, and Coho, whose population numbers, if not helped out with juvenile fish from hatcheries, would continue to decline due to the numerous dams in place that hinder natural migration and mating movements of those fish species, which decrease their reproductive rates. These fish are let out into the rivers and streams of the Columbia River Basin, where all the dams are located. In fact, many of the species of Salmon, Chinook, and other species that are being dealt with through fish hatcheries are on the endangered species list. Also, there is the fact that there is economic benefit in replenishing the fish supply in the rivers and streams, as well, in that it has been estimated that the fishing season, which lasts 6 weeks in the Basin, brought in 75,000 anglers, and $15 million to the economy. Not only that, but helping out salmon stocks in the Columbia River Basin actually helps improve the population of salmon in the Pacific, where fishing boats pull up nets full of catch for the marketplace.
Researchers for federal fish hatcheries will put traps in place in rivers to see how many fish return in a given year. One of the hatcheries once took a return where only 3 male and 1 female fish were caught, used them as a basis to produce fish in their hatchery, produced fish which were then put back into that stream, and after several years of doing this, now have a return of 257 fish (also p.4 of same research paper), thus showing a remarkable increase in population numbers because of the help that this fish hatchery brought. This shows hatcheries to have a conservational purpose, where it helps to conserve a species of fish from decline and extinction. It also shows that us humans can have a more symbiotic relationship with the ecosystems around us.
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