BX2123 EC5218: Tinaroo Dam Barramundi Sustainability Project Report

This project report provides a comprehensive analysis of the sustainability of barramundi in Tinaroo Dam, Queensland. It begins with a general background of the dam and the significance of barramundi as a key species. The report delves into the economic aspects of barramundi stock, including its lifecycle, current stock levels, and the potential threat of overfishing. An economic model is developed to calculate the optimal harvest rate, considering factors such as growth rates, carrying capacity, and price per kg, with a sensitivity analysis to assess the robustness of the estimates. The report then proposes and analyzes the effectiveness of policy instruments, specifically individual transferable quotas (ITQs), in managing the fishery. The analysis includes a cost-effectiveness evaluation, examination of underlying assumptions, distributional effects, and the impact of the policy on innovation and administration. The report concludes with a discussion of the policy's side effects and political/moral considerations, offering insights into sustainable management practices for the Tinaroo Dam barramundi fishery.

Running Head: BARRAMUNDI 1
Project Report for Sustainability of Tinaroo Dam Qld Barramundi
Name
Institution
Date

BARRAMUNDI 2
Contents
1. General Background.........................................................................................................................3
2. Economic background of sustainable barramundi stock in Tinaroo Dam Qld............................3
2.1 Barramunda at Tinaroo dam....................................................................................................3
2.2 The Life Cycle of the Barramundi............................................................................................3
2.3 The Stock of Barramundi..........................................................................................................4
2.4 Potential problem of overfishing...............................................................................................5
3. Economic Model................................................................................................................................5
3.1 Optimal Harvest Rate................................................................................................................5
3.2 Policy Instrument.......................................................................................................................8
4. Analysis............................................................................................................................................10
4.1 Cost effectiveness of the policy................................................................................................11
4.2 Assumptions underlying the model and policy instrument..................................................11
4.3 Equitable policy (distributional effect)...................................................................................11
4.4 Policy impact on innovation, effort to administer, monitor and enhance............................11
4.5 Policy side effects.....................................................................................................................12
4.6 Political and moral issues affecting the policy.......................................................................12
5. Conclusion........................................................................................................................................13

BARRAMUNDI 3
Project Report for Sustainability of Tinaroo Dam Qld Barramundi
1. General Background
The Tinaroo Dam stands as one of the major multipurpose dams in Australia. The dam boasts as
the largest artificial water body in the North Queensland (Queensland Government, 2020).
Predominantly, the dam’s main purpose includes recreation, hydroelectricity generation, water
supply and irrigation, and fishing. Today, the dam is a host to a wide range of aqua-life, such as
the barramundi. The barramundi is arguably the most treasured sports fish in Tinaroo dam and
Australia as a whole (Stunzner, 2019). This project report discusses how sustainability can be
achieved to ensure efficiency of at Tinaroo dam and enhance optimal exploration of the
barramundi using the individual transferrable quotas.
2. Economic background of sustainable barramundi stock in Tinaroo Dam Qld
2.1 Barramunda at Tinaroo dam
Although there are many species of fish and other aquatic animals in the dam, the Barramundi is
the most common stock. Mainly, this is because the Barramundi do not have any natural
predators and therefore can grow into large numbers (Queensland, 2020). The species breeds
well in salt water, and, therefore, due to lack of access to salty water, the species does not breed
in the dam. Therefore, each year, the lake is stocked with young Barramundi’s from the
Walkamin Research Station and Tableland Fish Stocking Society.
2.2 The Life Cycle of the Barramundi
In their natural habitat, the species has a complex life cycle comprising of the fresh water, marine
and estuarine phases (Government of Australia, 2011). During the wet season, the mature adult

BARRAMUNDI 4
barramundi move from fresh water regions to estuaries. Mainly, this is due to the fact that the
estuaries have the most favorable salinity conditions and temperatures that favor spawning (ABC
News, 2016). Spawning tends to occur during the night during the slack tide. Afterwards, the
hatched larvae move into a transitory tidal habitat which functions as nurseries. The juvenile
barramundi develop in the flood plain lagoons and mangrove during their first year before
moving to shallow coastal areas and then move back to fresh streams (Government of Australia,
2011). It is at this stage that they are transferred to the Tinaroo Dam where they stay for the
about three years as they mature into adults. It is worth noting that after one year, barramundi
usually attain a size between 30 to 40 centimeters develop into voracious predators.
2.3 The Stock of Barramundi
The stocking of barramundi in Tinaroo Lake is a valuable management tool. Overtime, the good
management of the stocking program has improved the status of declining barramundi stocks in
the region and created diversity that was not there before. Given that the species does not breed
in the lake, they have to be stocked repeatedly in order to maintain their numbers. Thus, the main
purpose of impoundment stocking is to create recreational fisheries that contribute to recreational
opportunities for the local community and tourist related income.
It is important to note that the barramundi were first stocked in Tinaroo dam in December 1985
using fingerlings from brood stock (Burrows, 2014). According to Simpson, Hutchison,
Gallagher and Chilcott (2002), approximately 1,295,000 of the fish were stocked into the
Tinaroo dam between 1995 and 2001. Between 2017 and 2018, approximately 54,550 more were
introduced into the facility from stocked impoundment permit (SIP) sales (Queensland

BARRAMUNDI 5
Government, 2020). In total, about 380,272 fish of this species have been stocked into the dam
from SIPS (Queensland Government, 2020).
2.4 Potential problem of overfishing
Without a doubt, all water bodies are under the threat of potential overfishing and the Tinaroo
dam is not an exception. By and large, overfishing is a looming problem given that the demand
for barramundi in the region is constantly growing. This is as a result of an increase in the
number of anglers who prefer to fish for barramundi at the lake. As it stands, approximately one
sixth of the Australian population actively fish in the in country’s fresh waters. Barramundi catch
by the commercial sector was approximately 1000 tons per annum between 1983 and 1987
(Parma, 2010). The numbers have grown exponentially ever since. Also, recreational fishing
and the increase in the number of sport fishermen in the region has led to a significant increase in
the demand of the barramundi in the lake, thereby creating potential for overfishing in the near
future.
3. Economic Model
3.1 Optimal Harvest Rate
Fishery management entails creating a balance between harvesting and its ecological
implications. It is thus important to fish in such a manner that the barramundi are sustainable and
not in danger of becoming depleted within the dam (Parma, 2010). The key to an optimal
harvest is to maximize catch in a sustainable manner as follows.

BARRAMUNDI 6
Consider a fishery, Tinaroo dam as an aquatic system comprising of a reserved and unreserved
area. Let x(t) and y(t) be the respective biomass densities of the barramundi fish population
inside reserved and unreserved respectively, at a time t.
dx
dt =rx ( 1− x
K ) −σ 1 x +σ 2 y−qEx (1)
dy
dt =sy (1− y
L )−σ 1 x +σ 2 y, x(0) >0, y(0) >0 (2)
Here, r and s are the intrinsic growth rates of the barramundi population inside the reserved and
unreserved areas, while K and L are the carrying capacities of the species, and q is the catch-
ability coefficient in the unreserved area. All these parameters are assumed to be constant.
An equilibrium point of the model is attained at the point where x = y =0. It can thus be proven
that the model has two non negative equilibriums, namely P*(x* y*) and P0(0,0). Thus, x* and
y* are the solutions for the following equations.
σ 2y= r x2
K − ( r−σ −qE ) x (3.1a)
σ 1x= (σ 2❑ −s ) y+ s y2
L (3.1 b)
Replacing the value of y from (3.1a) into (3.1b), results in the following equation
ax3 + bx2 + cx + d = 0 (3.2)
Where:

BARRAMUNDI 7
a= S r2
L σ 2 K2
b= 2 sr (r −σ1❑−qE)
Lσ 22 K
C=¿ ¿
d= ( s−σ2 ) r
L σ2
( r −σ1−qE ) −σ1 (3.3)
Thus, the solution for these equations is a unique positive solution where x = x*.
It is worth mentioning that a bionomic equilibrium point is achieved at the point when the total
cost incurred in harvesting the barramundi is equal to the total revenue gained from selling them
(Bounkhel and Tadj, 2015). At this point, the economic rent is wholly dissipated (Bounkhel and
Tadj, 2015). Assuming that p is the price per unit biomass of barramundi and c is the cost of
fishing per unit, then the net economic revenue at any time t is obtained by:
π (x , E , t )=( pqx−c ) E (4.1)
The bionomic equilibrium is P ∞( x ∞; y ∞; E ∞), where x∞; y∞; E∞ are the positive solutions of
x ˙=˙ y=π =0
Thus, we can obtain the optimal harvesting rate using the Pontryagin’s Maximum Principle to
establish a path for optimal harvesting. The present value J of a continuous time stream of
revenues will be given by J=∫
0
∞
e−δt ( pqx ( t )−c ) E ( t ) dt where δ is an instantaneous annual

BARRAMUNDI 8
discount rate (Bounkhel and Tadj, 2015). Thus, the objective is to maximize J subject to
equations (1) and (2) above and the constraint 0 ≤ E ≥ Emax (Bounkhel and Tadj, 2015).
The linked Hamiltonian is therefore represented by
H=e−δt ( pqx−c ) E+ℷ 1 ( t ) ⌈ ⌊ rx(1− x
K )¿ ¿ +
ℷ2 ( t ) [ sy ( 1− y
L ) +σ1 x−σ 2 y ] = σ ( t ) E +ℷ1 ( t ) [ rx ( 1− x
K )−σ1 x +σ 2 y ] +¿
ℷ2 ( t ) [ sy ( 1− y
L ) +σ1 x−σ 2 y ]
Here, ℷ 1 and ℷ 2 represent adjoint variables and e−δt ( pqx −c ) E+ ℷ1 qx is known as the switching
function. The optimal control E(t) that maximizes H must fulfill the following conditions E=
Emax, when σ ( t ) >0 and E= 0 when σ ( t ) <0 (Bounkhel and Tadj, 2015). This condition implies
that if the profit is positive, then it is beneficial to harvest up to the limit of available effort.
Therefore, the optimal harvest policy is E ( t )=
{ Emax, σ ( t ) >0
0 , σ ( t ) <0
E∗, σ (t )=0 ,
which suggests that the cost of
harvest per unit of effort is equal to the discounted value of the future marginal profit of the
effort at the steady state level.
Next, to find the path of singular control, the Pontryagin’s Maximum principle is applied. Using
the model, a singular path equation is obtained as B2
B2+ δ = p− c
qx∗¿ ¿ which when solved gives a
net economic revenue of π ( x∞ , y , E , t )=0

BARRAMUNDI 9
3.2 Policy Instrument
A fisheries subsidy is a direct or indirect financial support offered by the government to its
fisheries sector (Sharp and Sumaila, 2009). Such subsidies are helpful in supporting fishing
efforts artificially by making fishing more profitable than it would be without the subsidy. By
and large, there are a wide range of subsidies that the Australian government can implement to
boost the fishing activities at Tinaroo Dam. The subsidy can either be direct in the form of cash
grants, or indirect in the form of rebates and tax-breaks. Additionally, a transferable quota
system may be utilized.
It is imperative to note that the adoption of a transferable quota system (ITQ) could a go a long
way in regulating the level of fishing for barramundi in the Tinaroo dam. An individual
transferable quota (ITQ) is a type of ‘catch share’ system and a regulation tool employed by
governments to control fishing within their territories (Kenton, 2019). This tool has been
successfully implemented in Digha Fishery, in West Bengal India (Weerasekara, 2017).
Normally, ITQs are structured in such a manner as to bestow their owners restricted and
transferrable rights to a given share of the total allowable catch (TAC) (Sumalia, 2010). The
relevant authorities develop a TAC for a certain fish and then split the sum among the number of
fishers. These ITQs could be transferred from one individual to another through buying, selling
and leasing (Sumaila, 2010).
Principally, an ITQ is a mechanism for enhancing economic efficiency, rather than a tool for
promoting equity and conservation (Stafford, 2019). Studies indicate that where ITQs have been
adopted, the degree of economic efficiency has improved (Raines, 2016). For this reason, it
would be appropriate to initiate individual transferable quotas in the region that would help

BARRAMUNDI 10
regulate the degree of fishing of barramundi in Tinaroo dam. Predominantly, this policy is bound
to offer anglers a long-term stake at the fishery, eventually altering their behavior by eliminating
competition among them. It would bring rationality into the system and reduce the dangers of
overfishing. Consequently, this would lead to an increase in the level of economic efficiency at
the facility.
4. Analysis
Economic theory posits that the efficiency of an ITQ originates from the fact that it creates
private property in harvesting rights. In turn, this implies that the higher the quality of the
property rights with respect to factors such as exclusivity, transferability and permanence, the
better will be the efficiency of the system of ITQ (Johnson, 2012). Specifically, they encourage
fishers to harvest more safely and slowly, reduce overcapitalization and deliver a superior
harvest to the market. ITQs would significantly increase both public and private efficiency at
Tinaroo dam.
Graph 1.1: With and without an ITQ policy population of barramundi ten years from now
1 2 3 4 5 6 7 8 9 10
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
with policy
without policy

BARRAMUNDI 11
Source: (writers own work, 2020)
From the graph, one clearly notes that the policy will bring about effectiveness in the
management of the barramundi population at Tinaroo dam. As such, an ITQ policy is bound to
result in a rise in the total number of the barramundi over time since the level of fishing will be
controlled. Given that restocking is expected to take place over the ten year period, then the
population of barramundi will increase overtime. Contrariwise, if the policy is not implemented,
then the regulation of fishing would be minimal, and overfishing may take place. This in turn
could lead to decreases in the population of barramundi at the dam over the ten year period.
4.1 Cost effectiveness of the policy
It is worth pointing out that the cost effectiveness of the ITQ is based on its ability to help
minimize the total harvesting cost and/or maximize the total profits to fishers for catching a
certain quantity of fish. Thus, if the ITQ system is adopted in conjunction with the calculated
optimal rates, then a cost effective solution can be achieved that would result in both economic
efficiency and sustainability at the Tinaroo dam.
4.2 Assumptions underlying the model and policy instrument
The Pontryagin’s Maximum Principle is founded on the underlying assumption that they are
easily transferable from one fisher to another through selling, buying or leasing. Additionally, it
is based on the view that the introduction of ITQs would bring about an increase in profitability
and efficiencies in fisheries management.
4.3 Equitable policy (distributional effect)

BARRAMUNDI 12
By and large, an ITQ system is an economic tool, and not a sustainability and equity tool.
Therefore, as much as it will improve the degree of economic efficiency in the facility, it will not
bring about a distributional effect that supports equity with the society.
4.4 Policy impact on innovation, effort to administer, monitor and enhance
An effective ITQ would help to eliminate the compulsion of fishers to compete for the
barramundi and, instead encourage policy makers to consider the resources at Tinaroo Lake as
assets that have the potential to bring about a series of social and benefits over time. In turn, this
would reduce the tendency of fishers to exploit the resource.
4.5 Policy side effects
The policy has many negative consequences. To begin with, there are significant additional costs
that would be associated with the implementation and enforcement of the ITQ at the Tinaroo
dam. Enforcing the quotas requires the maintaining of accurate records on landings of all fish,
which leads to higher enforcement costs (Kokorsch, Karlsdottir and Benediktsson, 2015). The
system also presents a wide array of opportunities for fishers to cheat. As such, quotas can be
exceeded and high grading could take place. High grading refers to a case where a fisher culls
their catch and keeps the large, high marketable fish and discards the less desirable fish
(Johnson, 2012). Furthermore, leasing of quota could introduce inefficiencies into the system and
considerably reduce the economic benefits of the policy to the society.
4.6 Political and moral issues affecting the policy
The ITQ is influenced by various moral and political concerns. For instance, the option of
leasing results in ethical concerns since it makes quota acquisition less likely for active

BARRAMUNDI 13
fishermen. In turn, it results in the diversion of assets away from fishing communities to private
individuals and can result in a major financial strain on fishers along with the economic
diminution of fishing communities. Thus, it may result in the local community being worse off
than expected.
5. Conclusion
All in all, all factors taken into consideration, the management of the barramundi species in
Tinaroo dam can be effectively managed to enhance efficiency and economic sustainability over
the long term (Raines, 2016). The adoption of an ITQ system will go a long way in improving
the economic sustainability in the Tinaroo ecosystem. Further studies should be conducted on
how ITQs can be modified to not only enhance economic efficiency but also sustainability and
equity.

BARRAMUNDI 14
References
ABC News. (2016). The barramundi life cycle: Spawning occurs around river mouths and
maturing males move downstream during the wet season. ABC News. Retrieved 19 April
2020, from https://www.abc.net.au/news/rural/2016-11-23/barra-life-cycle/8050826
Bounkhel, M and Tadj, L. (2015). Optimal Harvesting Effort for Nonlinear 91Predictive Control
Model for a Single Species Fishery. Mathematical problems in engineering, 15(1).
Burrows, D. (2014). Translocates Fishes in Streams of the West Tropics Region, North
Queensland: Distribution and Potential Impact. West Tropics Management Authority.
Retrieved 18 April 2020, from
https://www.wettropics.gov.au/site/user-assets/docs/translocatedFishesInStreams.pdf
Government of Western Australia. Barramundi-icon of the Kimberly. Government of Western
Australia. Retrieved 17 April 2020, from
https://www.fish.wa.gov.au/Documents/recreational_fishing/fact_sheets/
fact_sheet_barramundi.pdf
JohFnson, A. (2012). Individual Transferable Quotas – Benefits for global fisheries. Open
Channels. Retrieved 18 April 2020, from

BARRAMUNDI 15
https://www.openchannels.org/blog/afjohnson/individual-transferable-quotas-benefits-
global-fisheries
Kenton, W. (2019). Individual Transfer Quota (ITQ). Investopedia. Retrieved 19 April 2020,
from https://www.investopedia.com/terms/i/itq.asp
Kokorsch, M., Karlsdottir, A. and Benediktsson, K. (2015). Improving or overturning the ITQ
system? Views of stakeholders in Icelandic fisheries. Maritime Studies, 14(15), 23-24.
Parma, M. N. (2010). Optimal Harvesting Of Fish Populations With Non‐Stationary Stock‐
Recruitment Relationships. Natural Resource Modeling, 4(1).
Queensland Government (2020). Tinaroo Dam. Queensland Government. Retrieved 18 April
2020, from https://www.daf.qld.gov.au/rsa/sips-dams-and-weirs/profile?dam=tinaroo-
dam
Queensland. (2020). Lake Tinaroo. Queensland. Retrieved 19 April 2020, from
https://www.queensland.com/attraction/lake-tinaroo
Raines, B. (2020). Ethical Issues in the Gulf Snapper Fishery. Sustainable Fisheries UW.
Retrieved 18 April 2020, from https://sustainablefisheries-uw.org/ethical-issues-in-the-
gulf-snapper-fishery/.
Stafford, R. (2019). Sustainability: a flawed concept for fisheries management?.Elementa.
Retrieved 18 April 2020, from
https://www.elementascience.org/articles/10.1525/elementa.346/

BARRAMUNDI 16
Stunzner, I. (2019). Do you know where your barramundi comes from?. ABC News. Retrieved
19 April 2020, from https://www.abc.net.au/news/2019-10-16/do-you-know-where-your-
barramundi-comes-from/11585426
Sumaila, U. R. (2015). A Cautionary Note on Individual Transferable Quotas. Ecology and
Society, 15(3), 36.
Sumaila, U. R. (2016). Trade policy options for sustainable oceans and fisheries. Bridges Africa.
Retrieved 16 April 2020, from
http://www.ictsd.org/bridges-news/bridges-africa/news/trade-policy-options-for-
sustainable-oceans-and-fisheries.
Weerasekara, Nadeeka. (2017). An Economic Analysis of a Total Allowable Catch-Individual
Transferable Quota System in a Developing Country Heterogeneous Fishery: An
Application to the Digha Fishery in West Bengal, India". Dissertations and Theses in
Agricultural Economics. 38.