Sunday, November 17, 2019

The reason salmons are overfished Essay Example for Free

The reason salmons are overfished Essay Description:   Ã‚  Ã‚  Preferred language style: English (U.S.).   This is for the resource economy class. The subject is `Why salmons are overfished and how to protect it. ` There are no special instructions. I want u guys write down the explanation of salmons first and get to the subject then. Thank u.   Salmon is a unique fish which follows a very unique lifecycle.   It has an elongated body and is covered with rounded and small scales.   Between the tail fin and the dorsal fin, a fleshy fin is present.    It belongs to the same family of fishes that certain other fishes such as trout, whitefish, etc, belong (Salmonidae).   Salmon fishes can grow to a length of 86 cms and can weigh about 3.6 kilograms.   Salmon is caught for its meat and also as game.   Salmon usually feed on smaller fishes, aquatic life and insects. The salmon are migratory in nature and hence are found in sea water and in fresh water.   It is usually found only in the northern hemisphere.   The life cycle of the salmon has really been unique in nature.   The female adult Salmon lay their eggs in rivers, ponds or lakes.   The spawn develop in the fresh water and slowly the young salmon migrate to the sea water.   In the sea and the oceans, the salmon grow up.   Once the Salmon are ready to breed, they move upstream from the seas into the rivers and towards inlands.   If the salmon cannot find their way to the sea, as the water body may be landlocked, they may grow and develop in the lake or pond it (MSN Encarta, 2007 NMFS, 2008).   The Salmon that grows up in the ocean would turn up exactly in the same place that they were born and grew up.   In order to reach the place of their birth, the salmon would have to travel upstream several hundreds or thousands of miles.   This is one of the unique characteristics of the Salmon, and only in certain areas of the world, would it be possible to move from a sea into a lake found inland.   Hence, Salmon are found only in certain parts of the world.   Another unique thing of the Salmon fish is that the adults spawn only once in their lifetime. Following their spawning, the adult male dies and this process is known as ‘semelparity’.   Depending on the characteristics of the fresh water the Salmon would be thriving in, individual characteristics are produced.   The juvenile Salmon that is actually produced would spend about one to three years in the more friendly fresh water lakes, rivers and ponds.   After this period, they would move into the oceans and the seas through the downstream of the river.   The female salmon usually produce about 3 to 5 nests during the season.   Following mating, the eggs hatch within 42 to 60 days (MSN Encarta, 2007 NMFS, 2008).   The young salmon fry that is produced would feed on the river aquatic life and plankton.   The juvenile salmon have parr marks on its body, which it would shortly lose after it enters the oceans.   They appear black in color and have white abdomen.   Initially, the salmon fish can process freshwater, and once they enter the sea, the metabolic processes in the salmon would change in such a way that it can now process seawater.   Even the mechanisms in the gills would change so that it can breathe in oxygen in seawater.   In the rivers, the salmon would be feeding on plankton and other aquatic life.   However, in the oceans, the salmon would be feeding on squids, marine fishes, amphipods, etc.   The Salmon would be remaining in the oceans for a period of 2 to 3 years.   It is usually beyond the fourth year that the salmon would be returning through the rivers to the land to spawn.   Several species of salmon would be spending their entire lifetime in the rivers and the lakes, and would not actually migrate into the seas.    Such species are known as ‘non-anadromous types’.   Sometimes although the salmon can actually migrate to the oceans during their life, some of the juveniels would remain back.   They would mate with the anadromous types.   The initial few years of the lifetime of the salmon is spent in the lakes for growing and developing.   Later they migrate to the seas and spend about half of their lifetime there.   In the last year or few months of their lifetime, the salmon would migrate from the sea to the place of birth and would spawn there (MSN Encarta, 2007 NMFS, 2008).   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   During the spawning period, the salmon develop a drab color.   However, certain species of salmon may develop brighter hues.   In the mating season, the salmon have a hooked snout and their backs appear to be humped.   Usually, the salmon prefer shallow water which contain rocks and gravel for spawning, as it offers the eggs a huge amount of protection from predators.   The water in these Shallow River or lakes needs to flow rapidly.   The mating process of the salmon is very unique indeed.   One of the parents makes a nest or ‘redd’ for the fertilized eggs to develop.   The female lays down the unfertilized eggs in the bottom of the nest.   The male then releases the sperms over these eggs. Following this, the female digs up the bottom of the riverbed to ensure that the earth covers up the eggs.   During the entire process of migrating to the river from the seas, building the nests and mating, the salmon would not consume any food.   Depending on the temperature, species and the flow of the water, the eggs of the salmon would hatch anywhere between 40 to 60 days.   Once the eggs of the salmon hatch, the newborn known as ‘alevins’ stay in the nest and feed on the nutrients present in the yolk sacs attached to their bodies.   Once these nutrients get exhausted, the young salmon are known as ‘fry’ and slowly come out from the nests. They now feed on small aquatic plants, insects and debris found in the riverbeds.   The fry grow and develop in the rivers and develop vertical bars on the sides of their bodies that help in camouflage (parr).   When the juvenile salmon are about to begin their journeys into the sea, they become bright silver in color and are known as ‘smolts’.   They would spend about 2 years in the oceans where they become sexually mature in order to reproduce.   Then they would begin their journey upstream (MSN Encarta, 2007).   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   There are slight amount of differences in the salmon found in the Pacific Ocean and in the ones found in the Atlantic Ocean.   The Pacific salmon would not return to the oceans after spawning once, but the Atlantic salmon would return upstream to their place of birth every year, breed and then return back into the ocean.   The breeding season for the Atlantic salmon is October to November.   An Atlantic salmon can live for up to 4 years, whereas a Pacific salmon can live for 4 to 5 years.   An Atlantic salmon would weigh 4 to 6 kgs in weight, and a Pacific salmon would weigh 7 to 11 kgs in weight (MSN Encarta, 2007).   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Salmon are caught in fresh waters and in sea waters for their meat, both on a small scale and on a large scale.   Fishing corporations use nets in order to catch the Salmon during the spawning season.   This may vary from one geographic location to another.   Different species of salmon also migrate during different seasons of the year in order to spawn.   Huge salmon fishing activities go on along the Atlantic and the Pacific coasts of North America.   More than 60, 000 humans work in the Salmon fishing industry and more than one billion is generated as revenue.   Some of the countries that are involved in the Salmon fishing business include USA, Canada, Britain, Russia, Japan, Norway and Denmark.    These fisheries also help to grow and develop the young salmon in artificial hatcheries.   These young salmon are collected from the nests and are incubated in the hatcheries.   They are then released into the rivers ahead of time.   The hatcheries offer protection for the young salmon from their natural predators.   However, the artificial salmon have a poor genetic variety as compared to their counterparts which are breed in the natural environment.   This can make them less resistant to disease, environment hazards and genetic diseases (MSN Encarta, 2007). However, there are several issues concerning the salmon currently, as it is being overfished in several parts of the world.   50 years back, more than 2.5 million to 5 million brood salmon existed in the oceans.   In 1970’s, about 800, 000 existed, which shrunk to 300, 000 by 1996.   In the year 2007, only about 80, 000 remain the oceans.   As Salmon spend a greater proportion of their lives in fresh waters, they are a great risk that they could be overfished and thus become extinct.   Several states in the US and Canada are considering to enlist the Salmon fish as endangered or threatened under their individual Endangered Species Statues. Further, the salmon that are in the spawning process are specifically targeted as they present in the fresh waters during this period.   As the spawning salmon are targeted, there is a greatest risk that the species is in a great danger of not multiplying.   In the Sacramento River, the Chinook Salmon were very common, growing and multiplying in huge quantities.   However, today, they have almost disappeared from their natural habitat.   The regional fisheries have actually invested more than 150 million dollars in order to save the species, but nothing can be done to save the Salmon in several parts of the Sacramento River.   The government and other organizations need to act fast if anything can be done to save the salmon. People feel that either too many Salmon are being removed from the river at any given time or that the Salmon are being removed at a wrong point of time.   The remaining fish that may exist in the river are at the risk of being attacked with disease or from predators.   However, some fisherman considers that the problems lie in the ocean itself that may be providing conditions unfavorable to the Salmon.   Some fisherman also considers that Salmon are often sucked into the irrigation tubes and irrigation canals of several irrigation projects that provide water for agricultural purposes. The problem could also lie in the fact that the oceans, rivers, lakes and ponds are much more polluted than they were actually were a few decades back.   The Chinook salmon is actually protected by Local rules and regulations In San Francisco region.   A Salmon would also require proper nutrition and food in order to survive the journey to the sea.   Scientists feel that a drop in several aquatic and marine lives can directly affect the salmon. The ocean currents that actually bring in plankton and krill required for the salmon have gone out of tune since 2005.   In 2005, several salmon which actually entered the oceans have actually died due to starvation.   In a study conducted in San Francisco, it was found that only 4 out of the 200 salmon reached the oceans (that is about 2 %).   Several dams and irrigations projects have actually ruined the path of the salmon and have made them more susceptible to predators (Felicity Barringer, 2008, William K. Stevens, 1999, Ian Main, 2006). Some of the reasons as to why the salmon are reducing in number could be as follows:- There has been a sudden increase in the amount of commercial, industrial and recreational overfishing.   These seem to be a major threat to the salmon as often the young ones and the spawning ones are caught.   However, fishing can be regulated and is within the control by jurisdiction. Aquaculture has been conducted in order to save the species of extinction by raising them in a controlled environment and releasing them when they are grown up.   However, often fish which are susceptible to diseases and which can spread infectious and genetic diseases to other fishes are produced and released. Irrigations projects could hamper the progress of the salmon from their birth place to the sea and vice-versa.   Salmon can often not find their way home from the oceans.   Besides, several salmon may fall prey to several predators on the way to the oceans.   In the city of Washington itself, more than 1000 irrigation projects hamper the progress of salmon.   In certain areas fish ladders have been introduced to help the fish through their natural course.   However, in the process several fishes have become injured and are unable to continue with their onward journey. Several forest operations have caused pollutions of the rivers.   Slit from several projects have made the rivers dirty and uninhabitable.   Trees have been removed near several rivers, making it difficult fro the salmon to bear the temperatures of the water. Farming and ranching activities have added further insult to the problem of salmons.   Livestock have disturbed aquatic life and farming activities have changed the quality of the water found in rivers. Mining the riverbeds for gravel has caused a lot of problems for the salmon.   The nest containing the developing eggs and alevins has been disturbed.   Rivers are often polluted from such activities. Several cities developing near important rivers have created a lot of problems for the salmon.   Waste water from homes and industries has polluted the river water making it difficult for the salmon to survive.   River water is often diverted to homes and industries for use, thus drying up the rivers. Artificial salmon hatcheries are also causing problems for the salmon.   Hatcheries usually collect male and female adult salmon, remove their sperms and unfertilized eggs, and artificially fertilize the eggs.   The eggs are then raised artificially and young fry are produced.   These fry may be released into the environment.   However, some of the fish are returned to the hatchery unknowingly.   This can cause several problems in the quality of salmon that are ultimately produced. Several other species such as muscles, crabs, aquatic plants, weeds, etc are competing with the salmon for spaces in lakes, rivers, and sea. Several aquatic lives that are protected are multiplying at uncontrollable rates, and directly feed on the salmon, thus affecting the numbers left in the oceans. Global warming also seems to be a problem for the salmon, as they usually prefer cooler waters for breeding and spawning. Through pollution and other activities in the rivers, the levels of oxygen are reducing, making it difficult for the salmon to survive. In Several places in the world, such as Greenland and even in parts of Canada, the temperatures have drooped during severely during winter times, making it more difficult for the salmon to survive in the rivers and the seas. The population of seabirds has increased which are constant predators for salmon. (The Oregonian, 2008, Felicity Barringer, 2008, Ian Main, 2006) Protection of Salmons need to be done involving several organizations including NGO’s, Governmental organizations, local groups, tribal’s, etc.   Besides, resources have to be allocated at very stages to help recover the populations of salmons.   A separate project strategy should be developed by various stakeholders for saving the salmon.   This project strategy should have certain goals which including saving the number of the existing adult and juvenile salmons.   The project should aim at reaching a particular target within a specified timeframe. The targets of the project should be achievable.   Various stakeholders and organizations should exhibit a collaborative effort.   Immense planning and sharing of responsibilities and roles is required.   Options should also be available in case a path is not feasible.   Activities in order to m monitor the events taking place, determining the outcome of the project, developing a modified strategy, etc, also need to be determined.   Some of the measures that may be required in order to protect the salmon include:- Protecting the existent salmon adult and juvenile populations Protecting areas and forests near the rivers and lakes Imposing rules and regulations to protect the salmon Working with wildlife and fisheries groups Using research in breeding and hatchery techniques Having irrigation projects that would not affect the salmon population Using genetic engineering in hatcheries Collaborative efforts from state government, central government, local groups, NGO’s, tribal groups, etc Developing reforms in the hatcheries (Dave G. Butcher, 2001, Madrona, 2000, James L. Connaughton, 2006)          References: Council on Environmental Quality (1999). ‘President Clinton and Vice President Gore Protecting Pacific Salmon.† The White House, 3 May 2008.   http://environmentalcommons.org/salmon.html Dave G. Butcher (2001). â€Å"Protecting Our Salmon.† British Columbia University. 3 May 2008. http://www.bced.gov.bc.ca/technology/sampunits/salmon.pdf Felicity Barringer (17 Mar 2008). â€Å"Chinook Salmon Vanish Without a Trace.† NY Times. 3 May 2008. http://www.nytimes.com/2008/03/17/science/earth/17salmon.html Ian Main (2006). â€Å"Fish Fate—Major Reasons Salmon Are in Trouble.† Ian Main. 3 May 2008. http://www.fishfirst.org/picts/documents/JLC_Salmon_Speech_1_25_06.pdf James L. Connaughton (2006). Columbia River Salmon Recovery: A Comprehensive and Collaborative Management Strategy.† White House Council on Environmental Quality. 3 May 2008. http://www-tc.pbs.org/emptyoceans/educators/activities/docs/Salmon-Scavenger-Hunt-fish-fate.pdf Madrona (2000). â€Å"A Shared Strategy for Recovery of Salmon in Puget Sound.† Draft Shared Strategy. 3 May 2008. http://www.sharedsalmonstrategy.org/files/SharedStrategyDraft10.20.00.pdf MSN Encarta. â€Å"Salmon (fish).† Microsoft. 3 May 2008. http://encarta.msn.com/encyclopedia_761558965_2/Salmon_(fish).html NMFS. â€Å"Sockeye Salmon (Oncorhynchus nerka).† NOAA Fisheries. 3 May 2008.  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   http://www.nmfs.noaa.gov/pr/species/fish/sockeyesalmon.htm The Oregonian (17 Mar 2008). â€Å"The salmon crisis arrives.† The Oregonian. 3 May 2008. http://www.oregonlive.com/editorials/oregonian/index.ssf?/base/editorial/12055443169430.xmlcoll=7 William K. Stevens (14 September 1999). â€Å"As a Species Vanishes, No One Can Say Why.† William K. Stevens. 3 May 2008. http://www.nytimes.com/library/national/science/091499sci-animal-salmon.html More Information: http://www.grinningplanet.com/2005/06-07/overfishing-article.htm http://www.pbs.org/wgbh/evolution/library/10/3/l_103_02.html http://news.bbc.co.uk/2/hi/science/nature/769646.stm

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