ECO-SYSTEMS
The natural habitat in the water and out is greatly effected due to over fishing, earlier I spoke of how bottom dragnets destroy the corral under the water but that is not the only thing effected. Many species are caught in the nest and die such as sharks, dolphins, birds and sea turtles. Many of these animals are killed in the nets. Seven million tons of the worlds catch gets thrown over the side, that’s a tenth of all the worlds catch that is wasted.
Other issues are that of depleting a natural predator from an area such as sharks or larger fish eating fish. A case of this is “in the USA in a bay millions of cow nosed rays have appeared, its been a complete boom in there numbers and this is because there is almost none of the predator sharks that eat them left. This means that the creatures that are eaten by the ray are also being depleted in the area because of the amount of rays. Another is shrimp and lobster in South Africa; they are also multiplying greatly in numbers due to the lack of predators. Some might say this is great because they are good money but soon they too will be over fished and we will be left with jellyfish and plankton, leaving the sea as an uninhabitable space of water”. (End of the line, Directed by Rupert Murry, national geographic, 2010)
The natural habitat in the water and out is greatly effected due to over fishing, earlier I spoke of how bottom dragnets destroy the corral under the water but that is not the only thing effected. Many species are caught in the nest and die such as sharks, dolphins, birds and sea turtles. Many of these animals are killed in the nets. Seven million tons of the worlds catch gets thrown over the side, that’s a tenth of all the worlds catch that is wasted.
Other issues are that of depleting a natural predator from an area such as sharks or larger fish eating fish. A case of this is “in the USA in a bay millions of cow nosed rays have appeared, its been a complete boom in there numbers and this is because there is almost none of the predator sharks that eat them left. This means that the creatures that are eaten by the ray are also being depleted in the area because of the amount of rays. Another is shrimp and lobster in South Africa; they are also multiplying greatly in numbers due to the lack of predators. Some might say this is great because they are good money but soon they too will be over fished and we will be left with jellyfish and plankton, leaving the sea as an uninhabitable space of water”. (End of the line, Directed by Rupert Murry, national geographic, 2010)
But it is not only in the water. Here is a case study of how over fishing is affecting the Cape Gannet; “Cape gannet chicks are facing starvation as a result of overfishing of sardines and anchovies off the coast of southern Africa, as well as an increase in predation by other species affected by the food shortage
Overfishing on the western coast of southern Africa is leaving other species to go hungry, with wide-reaching implications for the future of the Cape gannet, whose young are starving and exposed to increasing predation.
2m wingspan and can live for 25 years. Family ties have no bearing when it comes to predation, though: pelicans are the main predator of gannet chicks, along with kelp gulls and seals, as fish supplies dwindle.
The findings were revealed in a study by biologist Ralf Mullers of the University of Groningen in the Netherlands. Mullers spent four six-month stints on the Namibian island of Ichaboe and the South African island of Malgas, both uninhabited.
Half of the bird’s six breeding colonies are in Namibia, half in South Africa. Namibian populations have been dwindling since the 1960s as a result of the overfishing of sardines and anchovies; the last decade has seen a drop in South African populations too as the fish have moved from the west coast of the country to the south and east.
Mullers studied the behavior of parents and chicks, fitting 646 birds with GPS tracking systems to discover that adult birds fly 280 miles a day in search of food. They do not make longer flights if there is less food available, a sensible choice in evolutionary terms, according to Mullers.
Pelicans, also protected birds, have learned to supplement their traditional fish diet with gannet chicks – some weighing as much as 2kg – and slaughterhouse waste from pig farms. The study reveals ‘entire colonies’ of gannets being destroyed by pelicans.” (Overfishing sends Cape Gannet’s ecosystem haywire, Ecologist, 19 June 2009)
Overfishing on the western coast of southern Africa is leaving other species to go hungry, with wide-reaching implications for the future of the Cape gannet, whose young are starving and exposed to increasing predation.
2m wingspan and can live for 25 years. Family ties have no bearing when it comes to predation, though: pelicans are the main predator of gannet chicks, along with kelp gulls and seals, as fish supplies dwindle.
The findings were revealed in a study by biologist Ralf Mullers of the University of Groningen in the Netherlands. Mullers spent four six-month stints on the Namibian island of Ichaboe and the South African island of Malgas, both uninhabited.
Half of the bird’s six breeding colonies are in Namibia, half in South Africa. Namibian populations have been dwindling since the 1960s as a result of the overfishing of sardines and anchovies; the last decade has seen a drop in South African populations too as the fish have moved from the west coast of the country to the south and east.
Mullers studied the behavior of parents and chicks, fitting 646 birds with GPS tracking systems to discover that adult birds fly 280 miles a day in search of food. They do not make longer flights if there is less food available, a sensible choice in evolutionary terms, according to Mullers.
Pelicans, also protected birds, have learned to supplement their traditional fish diet with gannet chicks – some weighing as much as 2kg – and slaughterhouse waste from pig farms. The study reveals ‘entire colonies’ of gannets being destroyed by pelicans.” (Overfishing sends Cape Gannet’s ecosystem haywire, Ecologist, 19 June 2009)
SOCIAL
The overfishing also plays a role on the communities that rely on fishing to have financial backing. In western Africa many of the people rely on fishing for money, they go out everyday on small fishing boats and spend al day in the water and only catch a fraction in comparison to the major fishing boats. They then have to take their small catch and sell it at a market. They earn between eight and ten dollars a day. They then have to pay for water and the up keep of their boat and are left with sometimes two dollars to feed their family. They have been greatly affected in a negative way due to their governments letting the chines fish in their waters. This means that the locals only get the scraps that are left after the big fishing boats have gone out. It also means that more and more of these governments unemployment is growing meaning their homeless and informal settlements are growing out of control because the these fisherman have no money. This also results in not enough food to feed their families as 1.2 billion people rely on fish as their primary diet. All of these factors have lead to people migrating from these third world countries to Europe seeking work. What this means is that just from over fishing we can link illegal immigration and the unemployment rate growth. The fishermen go to Europe and try to make a living there, many of them die on the trip.
damaged coral reed
http://www.noaanews.noaa.gov/stories/images/reef-anchor-damage2.jpg
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