This presentation is done by Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Agricultura Resource Management”.
Basic bioeconomics model of fishing. In order to perform estimations and predictions of the bioeconomic impact derived from different management strategies, a dynamic modelling approach of the resource and the fishery as a whole is needed. In this Secetion we develop : (1) the static and dynamic versions of the Gordon-Schaefer (Gordon, 1953, 1954) model; (2) a distributed-delays fleet dynamics model based on Smith's (1969) model; (3) yield-mortality models; and (4) age-structured dynamic models (Seijo & Defeo, 1994a).
Basic bioeconomics model of fishing. In order to perform estimations and predictions of the bioeconomic impact derived from different management strategies, a dynamic modelling approach of the resource and the fishery as a whole is needed. In this Secetion we develop : (1) the static and dynamic versions of the Gordon-Schaefer (Gordon, 1953, 1954) model; (2) a distributed-delays fleet dynamics model based on Smith's (1969) model; (3) yield-mortality models; and (4) age-structured dynamic models (Seijo & Defeo, 1994a).
the presentation provides details regarding the natural and artificial feeds of fishes, purified and semipurified diets, feeds based on the moisture contents, the larval feeds including the most recent spray dried and vacuumdried feeds, microparticulate diets, the microencapsulated, the microcoated and the microbound diets, microextruded marumerisation, and particle associated rotated agglomeration
The traditional fishery byproducts are fishmeal, fish body and liver oils, fish maw, isinglass etc. Fish protein concentrate, fish albumin, glue, gelatin, pearl essence, peptones, amino acids, protamines, fish skin leather etc. are some other byproducts generally processed out of fish and fish waste.
Separation Surplus yield model (MSY, Fmsy, MEY, Fmsy)Degonto Islam
Economic variables are often included in the biological model that suggests the relationship between sustainable revenue, fishing cost and fishing effort.
For more than 50 years, it has been generally accepted that the fishing sector stood to gain from managing fisheries at the effort level producing maximum economic yield rather than maximum sustainable yield, which occurs at a higher effort level.
Surplus production models are also called as Holistic models. This model deals with total stock biomass along with fishing effort and yield. To operate this model, catch and effort data are needed as input data. These models could be computed with less input data unlike analytic models. This model does not take into account age and growth. Hence, it could be safely applied to tropical stocks, where calculation of age of tropical fish is more cumbersome.
Fertilized fish eggs are known as Fish seeds. In simple words, they are the baby fishes used for seeding new Ponds in fisheries. Fish seed transportation is a process by which transfer of fish seed from the hatchery or place of collection to the rearing ponds.
fish nutrition and feeding of fish. different methods of feeding fish. fish feeding behavior. daily feed requirements for fish. storage and selection of quality feeds keeping records of fish feeding and feeder types for fish. FCR and Uniform growth of fish are the ultimate goals to be achieved. university of veterinary and animal sciences Lahore.
the presentation provides details regarding the natural and artificial feeds of fishes, purified and semipurified diets, feeds based on the moisture contents, the larval feeds including the most recent spray dried and vacuumdried feeds, microparticulate diets, the microencapsulated, the microcoated and the microbound diets, microextruded marumerisation, and particle associated rotated agglomeration
The traditional fishery byproducts are fishmeal, fish body and liver oils, fish maw, isinglass etc. Fish protein concentrate, fish albumin, glue, gelatin, pearl essence, peptones, amino acids, protamines, fish skin leather etc. are some other byproducts generally processed out of fish and fish waste.
Separation Surplus yield model (MSY, Fmsy, MEY, Fmsy)Degonto Islam
Economic variables are often included in the biological model that suggests the relationship between sustainable revenue, fishing cost and fishing effort.
For more than 50 years, it has been generally accepted that the fishing sector stood to gain from managing fisheries at the effort level producing maximum economic yield rather than maximum sustainable yield, which occurs at a higher effort level.
Surplus production models are also called as Holistic models. This model deals with total stock biomass along with fishing effort and yield. To operate this model, catch and effort data are needed as input data. These models could be computed with less input data unlike analytic models. This model does not take into account age and growth. Hence, it could be safely applied to tropical stocks, where calculation of age of tropical fish is more cumbersome.
Fertilized fish eggs are known as Fish seeds. In simple words, they are the baby fishes used for seeding new Ponds in fisheries. Fish seed transportation is a process by which transfer of fish seed from the hatchery or place of collection to the rearing ponds.
fish nutrition and feeding of fish. different methods of feeding fish. fish feeding behavior. daily feed requirements for fish. storage and selection of quality feeds keeping records of fish feeding and feeder types for fish. FCR and Uniform growth of fish are the ultimate goals to be achieved. university of veterinary and animal sciences Lahore.
The Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docxmehek4
The Dynamics of an Open Access Fishery
Trond Bjørndal; Jon M. Conrad
The Canadian Journal of Economics / Revue canadienne d'Economique, Vol. 20, No. 1. (Feb.,
1987), pp. 74-85.
Stable URL:
http://links.jstor.org/sici?sici=0008-4085%28198702%2920%3A1%3C74%3ATDOAOA%3E2.0.CO%3B2-0
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The dynamics of an open access fishery
TROND BJBRNDAL Norwegian School of Economics
JON M. CONRAD Cornell University
Abstract. A discrete time non-linear deterministic model for an open access fishery is
developed and the equilibrium is characterized. The open access exploitation of North
Sea herring during the period 1963-77 is analysed. Alternative production functions are
considered and estimated for the Nonvegian purse seine fishery. The bionomic
equilibrium and approach dynamics are presented when prices and costs are changing.
The results indicate that the resource stock was saved from possible extinction by the
closure of the fishery at the end of the 1977 season.
Sur la dynumique d'une zone de pgches quund l'entrke est libre. Les auteurs developpent
un modele deterministe non-lineaire en temps discret d'une zone de p&ches ou l'entree
est libre et definissent les caracteristiques de l'equilibre. L'exploitation du hareng de la
Mer du Nord qui s'est faite sans entraves B l'entrte pendant la periode 1963-1977 est
analysee avec ce modele. Des fonctions de production de rechange sont examinees et
calibrkes pour la p&c ...
Mathematical models can help to better manage fishing - Encyclopedia of the E...TeXt10
Fishing provides an important part of the food for people in some developing countries. This can lead to a worrying cascade of overfishing, collapsing catches
and rising market prices, and the extinction of many species. How can we prevent this situation from becoming catastrophic and, on the contrary, stabilize it?
Mathematical modelling, by coupling ecological and economic dynamics, provides a better understanding of the dynamics of fisheries systems.
A SUSTAINABLE ‘MIDDLE WAY’ TO ECONOMIC RESPONSIBILITY IN ENVIRONMENTAL GOVERN...Ronin Institute
Jovita De Loatch
USC Department of Economics & School of International Relations ; Université Paris 1 Panthéon-Sorbonne, LAJP (UMR de droit comparé) ; Stockholm University, Juridiska institutionen
December 31, 2008
Traduire Nos Responsabilités Planétaires; Recomposer Nos Paysages Juridiques, Christoph Eberhard, dir., Bruxelles, Bruylant, Col. Bibliothèque de l’Académie Européenne de Théorie du Droit, pp. 583- 611, 2008
Abstract:
Discovering new paths to responsible governance requires alternative perspectives in the economic analysis of legal reforms to encourage sustainable development. The perspective presented herein, at its core, challenges economic analysis of law theorists to more fully encapsulate normative issues relating to sustainable development. This perspective equally challenges rights-based theorists advocating stewardship obligations to better appreciate the importance of economic incentives that permeate virtually all of our lives and drive the global economy, thus providing a translational bridge between these interdisciplinary landscapes. In general, economics asks questions about the assessment of value, the process of exchange and the choices made in the allocation of scarce resources, and this particular branch of legal theory evaluates the economic ‘efficiency’ of a legal rule or governing tool that affect these processes. The alternative viewpoint offered here evolves from a more progressive conception of the economic analysis of law. Although more narrowly focused liberal approaches have in the recent past overshadowed other lines of reasoning in the economic evaluation of legal rules, broader interpretations like this one may prove useful, particularly with regards to environmental issues. Accordingly, this chapter introduces a sustainable ‘middle way’ to economic responsibility in environmental governance by employing a law and economic model of sustainability derived as the Rawls-Nash economic efficiency criteria.
Populations and sustainability :- FisheriesDaniel Sandars
An hour long lecture on the role of Management and Operational Research in the governance of global fisheries. Global fisheries, like many open access natural resources, suffer for a tragedy of the commons effect. Population dynamic modelling can help provide the insights and understanding necessary to achieve sustainability.
A little summary of Age-structured models for fisheries in particular yield-per-recruit. The slides were developed from part 2 of Chapter 2 in the fantastic book "Modeling and Quantitative Methods in Fisheries" by Malcolm Haddon.
Authors: Daniele Baker and Derek Crane
Analysis of CPUE and Fishing Capacity of demersal fisheries in Kema 2, North ...IJAEMSJORNAL
Capture fisheries should be a sustainable economic activity aspect to provide good benefits to future resources. Sustainable marine fisheries resources exploitation requires a utilization rate lower than their availability. Therefore, the exploitation rate should not achieve the recovery ability of the resources in certain time. In fishing activities, for instance, there is a guideline not to catch fish over the Total Allowable Catch (TAC), 80% of the MSY. Information on the potency and the fishing capacity of tuna fisheries can be useful for the sustainable management of the resources. Also, this information can be used as a consideration for further management of the potency. There are two purposes of the study: (1) to analyze the CPUE (catch per unit effort) of demersal fisheries in Kema 2, North Sulawesi, for prediction of their potency, and (2) to analyze the efficiency of fishing capacity of the demersal fisheries in Kema 2, The study was done in two stages. The first was done by analyzing the potency using CPUE method (Shaefer models) to obtain the MSY, optimum effort and TAC (total allowable catch); and the second was done by analyzing the fishing capacity of demersal fisheries using DEA method to estimate the efficiency level of the fishing boats and devices in Kema 2. The result showed that the potency of demersal fisheries in Kema 2 was 71,700 tons per year and the optimum effort was 72,964 trips. Fishing capacity in demersal fisheries occurred in Kema 2 for the last 12 years was inefficient, especially for 2001. This may be caused by some factors such as trip operation, fishing duration, oil consumption, crew and operational cost. So, to manage the demersal resources in Kema 2, the TAC should be 57,520 tons per year. Based on the result, to increase the fishing efficiency, we should take into account of above factors. We suppose that the good means is reducing trip operation, fishing duration, oil consumption, crew and operational cost.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Post harvest technology”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Rice & Field Crop Production”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Rice & Field Crop Production”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Rice & Field Crop Production”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Rice & Field Crop Production”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Rice & Field Crop Production”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Rice & Field Crop Production”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Rice & Field Crop Production”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Rice & Field Crop Production”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Rice & Field Crop Production”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Fruit & Vegetable Cultivation”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Fruit & Vegetable Cultivation”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Fruit & Vegetable Cultivation”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Fruit & Vegetable Cultivation”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Fruit & Vegetable Cultivation”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Fruit & Vegetable Cultivation”. Note that the information included here is relevant to Sri Lankan condition.
This presentation is done by Export Agriculture students of 2010/11 batch of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Fruit & Vegetable Cultivation”. Note that the information included here is relevant to Sri Lankan condition
This presentation is done by Export Agriculture students of 2010/11 batch of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Fruit & Vegetable Cultivation”. Note that the information included here is relevant to Sri Lankan condition
This presentation is done by Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Fruit & Vegetable production”. Note that the information included here is relevant to Sri Lankan condition.
how to sell pi coins effectively (from 50 - 100k pi)DOT TECH
Anywhere in the world, including Africa, America, and Europe, you can sell Pi Network Coins online and receive cash through online payment options.
Pi has not yet been launched on any exchange because we are currently using the confined Mainnet. The planned launch date for Pi is June 28, 2026.
Reselling to investors who want to hold until the mainnet launch in 2026 is currently the sole way to sell.
Consequently, right now. All you need to do is select the right pi network provider.
Who is a pi merchant?
An individual who buys coins from miners on the pi network and resells them to investors hoping to hang onto them until the mainnet is launched is known as a pi merchant.
debuts.
I'll provide you the Telegram username
@Pi_vendor_247
when will pi network coin be available on crypto exchange.DOT TECH
There is no set date for when Pi coins will enter the market.
However, the developers are working hard to get them released as soon as possible.
Once they are available, users will be able to exchange other cryptocurrencies for Pi coins on designated exchanges.
But for now the only way to sell your pi coins is through verified pi vendor.
Here is the telegram contact of my personal pi vendor
@Pi_vendor_247
What website can I sell pi coins securely.DOT TECH
Currently there are no website or exchange that allow buying or selling of pi coins..
But you can still easily sell pi coins, by reselling it to exchanges/crypto whales interested in holding thousands of pi coins before the mainnet launch.
Who is a pi merchant?
A pi merchant is someone who buys pi coins from miners and resell to these crypto whales and holders of pi..
This is because pi network is not doing any pre-sale. The only way exchanges can get pi is by buying from miners and pi merchants stands in between the miners and the exchanges.
How can I sell my pi coins?
Selling pi coins is really easy, but first you need to migrate to mainnet wallet before you can do that. I will leave the telegram contact of my personal pi merchant to trade with.
Tele-gram.
@Pi_vendor_247
BYD SWOT Analysis and In-Depth Insights 2024.pptxmikemetalprod
Indepth analysis of the BYD 2024
BYD (Build Your Dreams) is a Chinese automaker and battery manufacturer that has snowballed over the past two decades to become a significant player in electric vehicles and global clean energy technology.
This SWOT analysis examines BYD's strengths, weaknesses, opportunities, and threats as it competes in the fast-changing automotive and energy storage industries.
Founded in 1995 and headquartered in Shenzhen, BYD started as a battery company before expanding into automobiles in the early 2000s.
Initially manufacturing gasoline-powered vehicles, BYD focused on plug-in hybrid and fully electric vehicles, leveraging its expertise in battery technology.
Today, BYD is the world’s largest electric vehicle manufacturer, delivering over 1.2 million electric cars globally. The company also produces electric buses, trucks, forklifts, and rail transit.
On the energy side, BYD is a major supplier of rechargeable batteries for cell phones, laptops, electric vehicles, and energy storage systems.
how to sell pi coins in South Korea profitably.DOT TECH
Yes. You can sell your pi network coins in South Korea or any other country, by finding a verified pi merchant
What is a verified pi merchant?
Since pi network is not launched yet on any exchange, the only way you can sell pi coins is by selling to a verified pi merchant, and this is because pi network is not launched yet on any exchange and no pre-sale or ico offerings Is done on pi.
Since there is no pre-sale, the only way exchanges can get pi is by buying from miners. So a pi merchant facilitates these transactions by acting as a bridge for both transactions.
How can i find a pi vendor/merchant?
Well for those who haven't traded with a pi merchant or who don't already have one. I will leave the telegram id of my personal pi merchant who i trade pi with.
Tele gram: @Pi_vendor_247
#pi #sell #nigeria #pinetwork #picoins #sellpi #Nigerian #tradepi #pinetworkcoins #sellmypi
The secret way to sell pi coins effortlessly.DOT TECH
Well as we all know pi isn't launched yet. But you can still sell your pi coins effortlessly because some whales in China are interested in holding massive pi coins. And they are willing to pay good money for it. If you are interested in selling I will leave a contact for you. Just telegram this number below. I sold about 3000 pi coins to him and he paid me immediately.
Telegram: @Pi_vendor_247
What price will pi network be listed on exchangesDOT TECH
The rate at which pi will be listed is practically unknown. But due to speculations surrounding it the predicted rate is tends to be from 30$ — 50$.
So if you are interested in selling your pi network coins at a high rate tho. Or you can't wait till the mainnet launch in 2026. You can easily trade your pi coins with a merchant.
A merchant is someone who buys pi coins from miners and resell them to Investors looking forward to hold massive quantities till mainnet launch.
I will leave the telegram contact of my personal pi vendor to trade with.
@Pi_vendor_247
Turin Startup Ecosystem 2024 - Ricerca sulle Startup e il Sistema dell'Innov...Quotidiano Piemontese
Turin Startup Ecosystem 2024
Una ricerca de il Club degli Investitori, in collaborazione con ToTeM Torino Tech Map e con il supporto della ESCP Business School e di Growth Capital
2. Fishery economics
Definition:
The production, distribution, and
consumption of fish and seafood and all
financial aspects of the fishing and seafood
industry (including aquatic life in fresh
water)
2
3. Introduction
• Fishery can be thought as a stock or stocks of
fish and the enterprises that have the
potential to exploit them
• The fish stock measured in terms of biomass,
is the natural capital of the system
3
4. • Factors which determine fish biomass;
– Ability to reproduce and provide new recruits
– Growth rate of individuals
– Natural mortality rate
– Rate of fishing mortality
4
5. • Fish stock can be increased with time if;
>
Recruitment of
new individuals
&
growth of existing
individual
Natural
mortality
&
fishing
mortality
5
6. Special Characteristics of Fisheries Resources
• Mobility
• Renewable
• Highly varied and poorly understood biology
• Dependence on ecosystem
• Tradition of open access
6
7. Renewable resource?
• A renewable resource is a natural resource
which can replenish with the passage of time,
either through biological reproduction or
other naturally recurring processes
7
8. Reasons to depletion of fish stock
• Overfishing due to;
Technology development
Boats with deep freezer facility
• Satellite technology
• By-catch
• water pollution
8
9. Relationship between fish stock & growth rate
when there is no harvesting
Growth Rate
Stock Size(kg)
XMSY
G*(x)
9
10. • When there is a small fish stock, the growth of
population is low
• As there are more fish in the water,
reproduction rates go up, causing the
population to grow
• Eventually however, due to crowding effects
and competition for food, the growth rates
decline
10
11. • At the far right point, the carrying capacity of
the fishery is reached and the stock is in
equilibrium
11
12. • Starting at a low level (the green dot) fish
reproduce in the first period
12
Growth Rate
Stock Size(kg)
13. • This leads to growth so that in the second
period the stock has increased
13
Growth Rate
Stock Size(kg)
15. • This process continues until the carrying
capacity of the fishery is reached
Natural equilibrium
for the fishery
15
Growth Rate
16. Sustainable yield
• Production of a biological resource (fish)
under management procedures which ensure
replacement of the part harvested by re-
growth or reproduction before another
harvest occurs
16
17. What is MSY?
• The highest possible annual catch for a given
fish stock that can be sustained over time, by
keeping the stock at the level producing
maximum growth
17
18. Population dynamics
• A fishery population is affected by three
dynamic rate functions:
– Birth rate
– Growth rate
– Mortality
18
19. Schaefer logistic Growth model
• x(t) = Size of fish stock at time t
• Growth of fish stock with time
)(
)(
td
tdx
)(
)(
xG
dt
tdx
19
20. r= Intrinsic rate of growth
(Rate at which the stock would typically grow
with no external effect)
K= Carrying capacity
(Largest stock size that can be achieved given
food supplies, habitat, etc.)
)1()(
K
xrxxG ttt
20
21. • shows that growth is proportional to
stock size
• Adds the complexity that growth
decreases with stock density,
• when stock size= carrying capacity, growth will
fall zero
rx
)1(
k
x
k
x
21
22. • Maximum growth rate can be found by 1st
derivative
• Set it equals to zero & solving for X,
02
K
rxr
2
KxMSY
22
23. • A critical issue in fisheries management is
what will happen to stock size over time
• Most purposes, size of an unexploited fish
stock will change through time according to
following relationship;
)()1( ttt xGxx
23
24. • With no harvest, stock size next year is the
sum of stock size this year & growth generated
by stock during the period of observation
• In terms of Schaefer model,
stock reach equilibrium when Xt = K
Because, G(Xt)=G(K)=0
So, X(t+1)=Xt
24
25. Fish stock & growth rate when there is a
harvesting
• When fishers begin to harvest, part or all of
the growth that occurs in any period is taken
out (harvested)
• so that growth in the stock doesn’t take place
or is reduced
25
26. Effect of harvesting to fish stock
Size of
stock
H1
H2
H3
Rate of growth
X’ X”XMSY
26
27. Schaefer logistic growth with harvest
• Periodic change in stock size with harvest can
be represented as,
• In this case,
Stock will reach an equilibrium where,
G(Xt) = Harvest
)()1( )( tttt HarvestxGxx
27
28. A more formal analysis of commercial
harvest
• Annual yield can be viewed as a function of
stock & amount of fishing effort applied to it
(think effort as a today’s standard boat)
Let Yt represent short run yield,
ttt EqxY
28
29. • E- Fishing effort
• q- catchability coefficient
(embodiment of technology that is used to
harvest fish)
29
30. • Fisheries production does not obey in
economic law of diminishing marginal
productivity
• Each additional unit of effort or stock size adds
the same amount to catch
30
32. • The same amount of effort will produce more
harvest when the stock size is higher & vice
versa
32
33. • For long run analysis- can use concept of
sustainable yield
• Sustainable yield curve shows the relationship
between level of fishing effort & level of
sustainable yield
• A sustainable yield is one that can be
maintained indefinitely because,
catch=growth
33
34. • To achieve sustainable harvest,
growth must equals to short run yield
qEx
K
xrx )1(
Growth Short run
yield
34
41. Sustainable yield function
• Substituting population equilibrium
equation(PEC) into Short run yield equation,
produces an equation for sustainable yield
function as a function of E(effort)
E
r
qKKx )( PEC
ttt EqxY
Short run yield
equation
41
43. • Stock size is obviously an important element
in determining sustainable harvest
• But it is subsumed in equation, because
equilibrium stock size is a function of effort
43
44. Sustainable Yield Curve
Catch/Harvest
Effort
Low level of effort
When E
Sustainable yield
B’coz growth increases with
decreases in stock size
Further increase of E
Decrease yield
B’coz further decrease of stock size
cause growth to fall
44
50. • To show the relationship between Effort &
Stock size, it is also useful to look at
sustainable revenue & cost in terms of stock
size
• TSR as a function of stock size;
)1(.
K
xrxPTSRX
Price Growth of fish
stock
50
51. • Now, we have identified the basic theories
needed to study the bio-economic equilibrium
• Bio economic equilibrium can be studied as 2
types;
1. Open access equilibrium
2. Private property equilibrium
51
55. open access equilibrium
• When all of the excess profits or economic
rent that attracts new entrants to a
developing fishery have been dissipated in the
costs associated with the additional fishing
effort
• The fishery is no longer attractive to new
entrants
55
56. • Usually occurs when fishing effort is higher
than that which will obtain the greatest yield
from a fishery
56
62. Maximum economic yield
• The value of the largest positive difference
between total revenues and total costs of
fishing (including the cost of labor and capital)
with all inputs valued at their opportunity
costs
62
64. Management of fishery resources
• Most important fisheries in the world at the
state of open access
• So, fisheries have to be manage carefully
• Have to change the equilibrium from open
access to private property equilibrium
64
65. • This can be done by 2 ways;
– Control the harvest of fish at optimum effort
– Reduce the fishing effort
65
66. • Above 2 status can be achieved by;
– Tax
– Quota
Tax
Tax on harvest of
fish
Tax on fishing
effort
66
67. Tax on harvest of fish
Effort
TR & TC
Tax
Y*
Y’
E* E
TR
TC
TR’
67
68. Tax on fishing effort
TR & TC
Effort
TR
TC’
TC”
TC
E* E
68
69. Theories of Agricultural Resource Management
(Past papers)
2009 :-
01.
a). Define the following terms;
1. Renewable resources
2. Non - renewable resources
3. Open access resources
4. Common pool resources
69
70. b). 1. Briefly explain the variable in fishery
2. "Increase in fishing effort always increase the
profit in fishery" Comment on this.
70
71. 2010 :-
01. a). With the use of suitable illustrations
describe the following in relation to
fishery.
1. Sustainable yield.
2. Maximum sustainable yield.
3. Maximum economic yield.
4. Open access equilibrium level.
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72. b). The effort catch relationship (production function) of a
fishery is given by,
Y = 90E - 2E2
Where Y is the sustainable yield measured in
kilograms of fish and E is fishing effort measured in
number of fishing trips. Each fishing trip costs Rs.
900.00. Fish sell at Rs. 40.00 per kilogram.
Determine the following
1. Maximum sustainable yield, corresponding level
of fishing effort and private profit.
2. Maximum Economic Yield, corresponding level of
fishing effort.
3. Find the open access equilibrium level of effort.
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73. 2013 :-
04.
a). Define the term "Fishery"
b). Briefly explain the variables in fishery.
c). "Increase in fishing effort always increase the
profit in fishery" Comment on this
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74. d). The effort catch relationship ( production function ) of a
fishery is given by,
Y = 1200E - 2E2
Where Y is the sustainable yield measured in kilogram of
fish and E is fishing effort measured in number of fishing
trips. Each fishing trip cost Rs. 900.00. Fish sell at Rs. 40.00.
per kilogram.
Derive the following
1. Maximum effort which yields no yield
2. Maximum sustainable Yield, corresponding level of fishing
effort and private profit.
3. Maximum Economic Yield, corresponding level of fishing
effort.
4. Find the open access equilibrium level of effort.
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