Data Management Plan

This pilot study follows the movements of 6 derelict fishing nets over time to study how far derelict nets can travel within an atoll, and how long they remain stationary. Six floating derelict fishing nets were located and tagged with satellite buoys in Pearl and Hermes Atoll in the Northwestern Hawaiian Islands during a marine debris removal mission in 2018. Locations of the 6 nets were transmitted every four hours from 09-30-2018 until the buoys broke free or stopped transmitting due to technical reasons. Last known stationary locations were surveyed on a return mission in September of 2021, and 4 of the 6 nets were relocated.

Geographic extent of tagged derelict fishing nets

Lineage Statement:
Data were downloaded using ELB 3010 Manager software. Locations were imported into csv file, symbols in coordinates were replaced in excel, then the files were loaded into the software program R. In R, date and time were separated and formatted to have consistent formats, and coordinates were converted to decimal degrees. Several points of bogus transmissions were removed, and all files were combined into one (raw data is one file for each buoy for each month).

Process Steps:

• Download data Open ELB3010 Manager Software OLD SOFTWARE VERSION: Right click on the map and minimize to bring the dashboard into view Open buoy log (T:\MarineDebris\MD Operations\NWHI\2018\Data\Spatial\Satlink\Positions) to see which ones are still active. Find the last timestamp for each buoy Example: stored time column: 21/11/18 16:45:15 In ELB manager, click on the red checkmark icon with the “I” on it. A window will open to show the last positions. Show Last 400 should be sufficient. Next to the filter name button, select the buoys one at a time, click Update (in the top right corner) and select the records since the last download. Record the latest date/time stamp in the log sheet. Once they are highlighted, right click and select Export… Navigate to the Positions/workspace folder and create a folder with today’s date. Save the file with the default name, but add an underscore and the last 2 digits in the buoy ID number (ex: Export1812102007_00) NEW SOFTWARE VERSION: In ELB manager, the three buoys should show up in a list on the left half of the screen. Right click and select ‘Export’ from the menu. In the pop up window, apply the filter ‘Last days’ and select something reasonable according to the last download in the buoy log. Save the file with the default name here: T:\MarineDebris\MD Operations\NWHI\2018\Data\Spatial\Satlink\Positions\workspace\raw_data Click Export to file, Accept, and close the window. Repeat for each buoy.
• Convert text files to csv Individual values are separated by semicolons, not commas, like excel is expecting. Change that in notepad. Open notepad, and open each csv file (to locate, navigate to folder and select ‘all files’ for type. Create a new first line and type: sep=; Save file, open next file, and do the same thing
• Convert coordinates from degrees decimal minutes to decimal degrees and exclude extra information Navigate to the raw data folder and open the csv files in excel and convert symbols to readable characters for R (may help to sort files by date modified) Highlight the latitude and longitude columns and select the ‘find and replace’ tool - replace ‘°’ with ‘/’ - replace ‘' ’ with ‘/’ (make sure to include a space after ' ) - replace ‘,’ with ‘.’ Save file here: T:\MarineDebris\MD Operations\NWHI\2018\Data\Spatial\Satlink\Positions\workspace\excel_replace_values_clean_data\2021 Save with default name, and add ‘_replace’ to the end of the file name For R script: Navigate here: T:\MarineDebris\MD Operations\NWHI\2018\Data\Spatial\Satlink\Positions\R code and open 1_format_lat_long_date_time_from_raw R code converts coordinates to decimal degrees and converts date and time into a readable format for calculating summaries. All raw files are combined into one csv file.

Locations were mapped in ArcGIS 10.6.1 software to estimate accuracy

Data can be accessed online via the NOAA National Centers for Environmental Information (NCEI) Ocean Archive.

NOAA IRC and NOAA Fisheries ITS resources and assets.