17.5. Financial Flow Sector
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is factored in along with egg production at each age/weight (EGGS AT
AGE) that results in spawning (SPAWN). The release of eggs into the water
column is represented by the LIVE EGGS stock. The population of eggs is
reduced (DIE EGGS) by a fixed egg mortality rate (EGG MORT) and the
surviving eggs hatch into larvae, or naturally produced larval fish (NAT
AGE 0). These larvae die (DIE AGE 0) at a very high but constant rate of
natural mortality (MORT AGE 0), and the survivors move into the stock of
naturally produced age 1 fish (NAT AGE 1).
Once fish pass into the MATURE FISH stock , they are subject to loss from
fishing mortality for the remainder of their lives, which is a lifespan ranging
from age 3 through age 10 in this model. A predetermined rate of fishing
mortality (CATCH RATE), expressed as a percentage removal of fish from
each cohort at the beginning of each model run, results in annual fishery
landings (CATCH). These landings reflect the summation of the numbers of
fish from each age class that were caught. Since price is dependent on
size/age and weight, the numbers of fish landed are converted (WEIGHT
AT AGE) into weight at age values (CATCH WEIGHD that are then input
into the financial flow sector. In the financial flow sector, they are converted into a revenue stream that will offset the cost of operating the hatchery. One other loss to the MATURE FISH occurs when fish move out of the
fishing area (EMIGRATION) and are effectively no longer part of the population. Emigration has been set as a fixed value that is subtracted annually
from each cohort of fish.
17.5. Financial Flow Sector
The Financial Flow sector compares the total fishery value, computed as a
positive or negative net profit. These profits result from both the addition of
fish to the ecosystem via the enhancement process, and their progeny as
they grow and recruit to the fishery. The accumulated annual operational
costs and the capital debt , plus interest , incurred to build the hatchery are
paid for by the value of the fishery yield.
To run this sector, the following variables are required as inputs prior to
a model simulation : 1) the amount of money borrowed for construction of
the hatchery, or at least the cost of that portion of the hatchery dedicated to
enhancement (INITIAL LOAN AMOUNDj 2) the annual interest rate on the
loan (INTEREST RATE); 3) the cost per fish (COST PER FISH), which is the
price paid to the hatchery for the fish and incorporates the energy, personnel, fish food and maintenance costs of the hatchery; 4) the numbers of fish
raised annually for release (FISH RAISED), which is a ghosted variable from
the Hatchery sector; 5) the price per unit weight paid to the fisherman for
the fish caught (PRICE)j and 6) the total weight of the landed fish (SUM
CATCH WEIGHT), which must be input, and generated in the Life History
sector. All except the FISH RAISED and SUM CATCH WEIGHT variables,
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is factored in along with egg production at each age/weight (EGGS AT
AGE) that results in spawning (SPAWN). The release of eggs into the water
column is represented by the LIVE EGGS stock. The population of eggs is
reduced (DIE EGGS) by a fixed egg mortality rate (EGG MORT) and the
surviving eggs hatch into larvae, or naturally produced larval fish (NAT
AGE 0). These larvae die (DIE AGE 0) at a very high but constant rate of
natural mortality (MORT AGE 0), and the survivors move into the stock of
naturally produced age 1 fish (NAT AGE 1).
Once fish pass into the MATURE FISH stock , they are subject to loss from
fishing mortality for the remainder of their lives, which is a lifespan ranging
from age 3 through age 10 in this model. A predetermined rate of fishing
mortality (CATCH RATE), expressed as a percentage removal of fish from
each cohort at the beginning of each model run, results in annual fishery
landings (CATCH). These landings reflect the summation of the numbers of
fish from each age class that were caught. Since price is dependent on
size/age and weight, the numbers of fish landed are converted (WEIGHT
AT AGE) into weight at age values (CATCH WEIGHD that are then input
into the financial flow sector. In the financial flow sector, they are converted into a revenue stream that will offset the cost of operating the hatchery. One other loss to the MATURE FISH occurs when fish move out of the
fishing area (EMIGRATION) and are effectively no longer part of the population. Emigration has been set as a fixed value that is subtracted annually
from each cohort of fish.
17.5. Financial Flow Sector
The Financial Flow sector compares the total fishery value, computed as a
positive or negative net profit. These profits result from both the addition of
fish to the ecosystem via the enhancement process, and their progeny as
they grow and recruit to the fishery. The accumulated annual operational
costs and the capital debt , plus interest , incurred to build the hatchery are
paid for by the value of the fishery yield.
To run this sector, the following variables are required as inputs prior to
a model simulation : 1) the amount of money borrowed for construction of
the hatchery, or at least the cost of that portion of the hatchery dedicated to
enhancement (INITIAL LOAN AMOUNDj 2) the annual interest rate on the
loan (INTEREST RATE); 3) the cost per fish (COST PER FISH), which is the
price paid to the hatchery for the fish and incorporates the energy, personnel, fish food and maintenance costs of the hatchery; 4) the numbers of fish
raised annually for release (FISH RAISED), which is a ghosted variable from
the Hatchery sector; 5) the price per unit weight paid to the fisherman for
the fish caught (PRICE)j and 6) the total weight of the landed fish (SUM
CATCH WEIGHT), which must be input, and generated in the Life History
sector. All except the FISH RAISED and SUM CATCH WEIGHT variables,