-
Notifications
You must be signed in to change notification settings - Fork 9
Simulation Setup
Setting up the files needed to run bioenergetics simulations
Once you were able to successfully install and open FB4 you are ready to run bioenergetics simulations. To run a basic simulation, you will need to supplement the program with Initial Settings and Input Files.
You must first decide on the species you want to use for the simulation. Under the Initial Settings tab, select the species of interest by scrolling through the dropdown menu under Species. You can see the species’ common and scientific name, along with the reference and parameters value on the right-hand side of the screen.
You must then select the duration of your simulation. The duration of the simulation must not exceed the length of time found in the Input Files. In addition, the simulation days are arbitrary and do not fall under any calendar constraints (i.e., day of year). Type your first day in the Initial Day box and your last day in the Final Day box. The days you input here will be used to determine the range of data from the input files to run the simulations.
All simulations require you to input an initial weight (in grams of wet weight) for the fish used in the simulation. Make sure you use a relevant weight that corresponds to the life stage of the species model you are using.
This parameter is used to convert oxygen consumption into an energy unit (Joules/grams of O2) that is compatible with the modeling process. The default value was taken from Stewart et al. 1983 but be aware that all species do not require the same coefficient (see Elliot & Davison 1975 for more information).
This is where you decide what kind of simulation you want to run. By selecting Final Weight, you are telling the program that you want your fish’s final weight (in grams of wet weight) to equal the value you input in the box. The program will then iteratively adjust daily consumption so that the final weight calculated from the simulation matches the final weight you used as an input.
If you select Consumption, the program will use the value you input in the box (in grams of total prey wet weight) and assign the fish a daily consumption value so that the total consumption value from the simulation matches the consumption value you used as an input.
By selecting Ration, you are telling the program to feed the fish a % of the fish’s wet body weight every day.
Lastly, if you select p-value, the program will calculate a consumption value based on maximum consumption (Cmax) on any given day. Remember that Cmax will vary depending on water temperature and fish body mass.
Input data files contain information that might have been collected in the field, retrieved from historical archives, or pulled from scientific literature. These files are created outside FB4 and are loaded automatically by the program once it is launched. Not all simulations require the same input files but all simulations require the files in the Main Inputs folder to be filled out.
The Main Input files include: Temperature, Prey Energy Density (Prey_E), Prey Proportions (Diet_prop), Predator Energy Density (Pred_E), and in some instance, Indigestible Prey (only if using Equation 3 for waste losses; see Stewart et al. 1983). All files are saved in .csv format. Default files have been provided with the Fish Bioen 4.0 folder but these can be modified to reflect your own data. To do so, simply replace the days and input data with your own data and save the .csv file before launching FB4. Data are linearly interpolated for the days where the data are missing. You must always have the same number of prey items for each of the input files (except Predator Energy Density) you plan on using for the simulations.
Once you give FB4 the input data you want to use for your simulation, you can visualize them by selecting the Input Files tab. However, you must make sure that you filled out the Initial Day and Final Day sections under the Initial Settings tab. This will allow you to visualize the input data for the time range you want to run your simulation for. You will also notice that the plots generated under the Input Files tab are reactive. This means that the plots will automatically adjust to reflect the Initial Day and Final Day of your simulation.
Once you have inspected your input data and arranged your initial settings, you can run your simulation. To do so, go to the Output tab and the program will run. Under this tab, you can see the results of the simulation on a daily basis under the Table tab. To view different outputs, select within the Variables box and many output options will become available. Select the ones of interest and they will appear in the table. Once you have all the data you need, you can download them into a .csv file onto the Fish Bioen 4.0 folder. To do so, select the Download button and save the file to the folder.
It is also possible to visualize the outputs in a plot format. To do so, select the Plot tab. This will bring you to a plot with 2 y-axes. You can modify the variables found on either y-axes or the x-axis by scrolling down the dropdown menus below Plot Output.
Finally, by selecting the Summary tab, you will be able to see the final weight, consumption and p-value calculated or used for the simulation. Keep in mind that the p-value is irrelevant if you choose to run a simulation using the Fit to: Ration option.