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Overharvesting

Overharvesting is a serious threat to many species, but particularly to aquatic species. There are many examples of regulated commercial fisheries monitored by fisheries scientists that have nevertheless collapsed. The western Atlantic cod fishery is the most spectacular recent collapse. While it was a hugely productive fishery for 400 years, the introduction of modern factory trawlers in the 1980s and the pressure on the fishery led to it becoming unsustainable. The causes of fishery collapse are both economic and political in nature. Most fisheries are managed as a common (shared) resource even when the fishing territory lies within a country’s territorial waters. Common resources are subject to an economic pressure known as the tragedy of the commons    in which essentially no fisher has a motivation to exercise restraint in harvesting a fishery when it is not owned by that fisher. The natural outcome of harvests of resources held in common is their overexploitation. While large fisheries are regulated to attempt to avoid this pressure, it still exists in the background. This overexploitation is exacerbated when access to the fishery is open and unregulated and when technology gives fishers the ability to overfish. In a few fisheries, the biological growth of the resource is less than the potential growth of the profits made from fishing if that time and money were invested elsewhere. In these cases—whales are an example—economic forces will always drive toward fishing the population to extinction.

Explore a U.S. Fish&Wildlife Service interactive map of critical habitat for endangered and threatened species in the United States. To begin, select “Visit the online mapper.”

For the most part, fishery extinction is not equivalent to biological extinction—the last fish of a species is rarely fished out of the ocean. At the same time, fishery extinction is still harmful to fish species and their ecosystems. There are some instances in which true extinction is a possibility. Whales have slow-growing populations and are at risk of complete extinction through hunting. There are some species of sharks with restricted distributions that are at risk of extinction. The groupers are another population of generally slow-growing fishes that, in the Caribbean, includes a number of species that are at risk of extinction from overfishing.

Coral reefs are extremely diverse marine ecosystems that face peril from several processes. Reefs are home to 1/3 of the world’s marine fish species—about 4,000 species—despite making up only 1 percent of marine habitat. Most home marine aquaria are stocked with wild-caught organisms, not cultured organisms. Although no species is known to have been driven extinct by the pet trade in marine species, there are studies showing that populations of some species have declined in response to harvesting, indicating that the harvest is not sustainable at those levels. There are concerns about the effect of the pet trade on some terrestrial species such as turtles, amphibians, birds, plants, and even the orangutan.

Questions & Answers

Black market what is the meaning
Bless Reply
where there is illegal transactions of goods or services. where there illegal goods or services are sold.
Azhar
Scarcity is the major problem of any economy which is the limited resources an economy has in order to produce its country's unlimited wants/needs. Therefore, scarcity is the key term beyond the study of Economics.
Bature Reply
what is supply
Rahul Reply
Like the demand, the supply demonstrates the quantities that will be  sold at a certain price. But unlike the demand, the supply relationship  shows an upward slope. This means that the higher the price, the higher the  quantity supplied.  Producers supply more at a higher
Nazneen
or we can say that By supply we mean various quantatirs of a commodity which a producer will offer for sale at different possible prices over a given period of time
Nazneen
What is scarcity?
Jubille Reply
having unlimited needs and wants in a world of limited resources
William
what are the indicator of over population
Accorobatic Reply
Inefficiency of natural resources
Adekunle
Low PCI .
abhinav
resources are limited and wants are unlimited
Nazneen
limited resources
Nazneen
what product market?
Gayflor Reply
explain demand
Bless Reply
what is economics
Murali
Economics is the social science that studies the production, distribution and consumption of goods and services.Economics focuses on the behaviour and interactions of economic agents and how economies work.
Preeti
ok
SAGAR
Pls what is national income?
Ishmael
demand is the number of buyers. as the price of goods is increase, the buyers will not consider to buy the goods, so the demand will decreases
Pung
National Income is the aggregate monetary value of all final goods and services produced in an economy in an year .
abhinav
Why pecularities of land has no economic significance, What the economic bad, effictive demand?
James
Demand is a quantity of goods that a consumer is willing to buy at different prices over a given period of time
Nazneen
Define law of demand
Nazneen
what is deadweightloss
francis Reply
hi
Bless
deadweight loss is the allocative inefficiency.... when the equilibrium for good or services is not achived.
Azhar
hi
Azhar
hi
azaloo
hii too
Jackson
Hello
Micah
how are you all?
Azhar
I am here been sick but here
Amanda
may you get well soon Amanda
Azhar
What are the implications of classical Economics?
Micah
What are the implications of classical Economics school of thought?
Micah
Dead weight loss is an inefficient allocation of resources, especially through taxation or restrictions.
Ezeigwe
Classical Economics had an influenced by ancient economic principle and theory.
Ezeigwe
yec
Yasinta
nice
Amanda
hello please what is localization of industry
Bless Reply
price is tantalisingly the only factor determining demand which can be analyze the view
Sinit Reply
Price is tantalizingly the only factor determining demand which can be analyze the view
Sinit
what is scarcity
Sharkdanny Reply
the state of being scarce or in short supply; shortage.
Abdirahin
what is meant by an abnormal demand curve?
Samuel Reply
what is microeconomics
Berun Reply
micronomics can be define as that part of Economics that deals with small scale business. e.g. House hold stuff
Amodu
Micro economics is the study of individuals, households and firms' behavior un decision making and allocation of resources
Christian
what is underemployment
Xornam Reply
It is the situation where the available resources are not used to it optimum
Bless
state the law of diminishing returns
Bless
Bless, the law of diminishing returns state that one point, adding a single worker will result in a decrease of production.
David
it is a situation where by people are employ but work under their potential
Akua
David please go into details kk
Bless
Akua pls when you say people alone? what about facilities?
Bless
Definition of underemployment. 1 : the condition in which people in a labor force are employed at less than full-time or regular jobs or at jobs inadequate with respect to their training or economic needs
Boahen
OK that is good
Set
I am new here
Taimoor
what does law of demand says?
Samuel
with a diagram explain fairy elastic demand
Samuel
comprehensive answer for public finance is the money that a government has available to spend from taxes and borrowing.
wilflay Reply
what then comprises of public opinion
Raphael
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
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Source:  OpenStax, University of georgia concepts of biology. OpenStax CNX. May 28, 2013 Download for free at https://legacy.cnx.org/content/col11526/1.2
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