What is the Billfish Satellite Logbook System?
In order to assess, monitor, and promote conservation of the valuable billfish resource, CABA is supporting a state-of-the-art satellite logbook catch and effort reporting system executed by University of Miami scientists. This satellite logbook system is the first of its kind- and is implemented with a goal to pinpoint locations and densities of billfish encounters on sportfishing vessels throughout the region relative to oceanographic features and proximity to other fishing activities. The main objective is unequivocally to assess the billfish resource through the most sound scientific data acquisition possible with the utmost precision. This data will be used by the University of Miami’s billfish science team to assess the resource to promote its value and conservation to governing bodies and policy-makers throughout the region. A secondary benefit of the satellite logbook system is an added-value to users to monitor their fleet and make decisions for their daily catch-and-release fishing activities.
The CABA/University of Miami billfish satellite logbook system, often informally referred to as “the box” by CABA members, consists of three hardware components: A handheld waterproof Motorola Android smartphone, a junction box, and a Thorium satellite antenna.
The billfish satellite logbook system utilizes an Android smartphone device programmed to have a touchscreen application in which a user enters information via quick push-button options. This information includes fishing mode (bait, fly, etc), species encountered, number of raises, number of bites, and number of fish caught and released per each “encounter” with species during fishing. The Android passes this information along wirelessly via Bluetooth connection to the junction box (depicted above). The junction box then relays entered data and receives position data through a Thorium satellite antenna. The Thorium unit transmits and receives all data via the Iridium satellite constellation. As this data is entered and transmitted, it is sent real-time to the University of Miami Billfish Science Laboratory. Data acquired includes real-time position reports of vessels while fishing and data on all encounters with fish- including lat/lon information, timestamps, fishing mode, species, and numbers of raises/bites/caught fish. Furthermore, the billfish satellite logbook system has a option to enter longline encounters so that the University of Miami Billfish Science team can map and estimate commercial fishing pressure.
The Billfish Ecosystem
A major advantage of the Billfish Satellite Logbook System is the ability to log and discern billfish encounters relative to oceanographic and ecosystem dynamics. Habitat compression is a prominent characteristic of the eastern tropical Pacific along the Central American Isthmus that reduces the volume of suitable habitat for billfishes through surfacing of the oxygen minimum layer (Prince et. al, 2006; Ehrhardt and Fitchett, 2006 Read: ON THE SEASONAL DYNAMIC CHARACTERISTICS OF THE SAILFISH, ISTIOPHORUS PLATYPTERUS, IN THE EASTERN PACIFIC OFF CENTRAL AMERICA).
The UM Billfish Science team linked habitat compression to oceanographic and climate characteristics, including wind-driven upwelling and sea height condition . Our studies further linked these processes to prey availability and seasonal migration (Ehrhardt and Fitchett, 2006). The Billfish Satellite Logbook System allows CABA and the UM Billfish Science team to link spatially explicit real-time billfish availability data to real-time ocean data for the purpose of identifying “hot spots” of billfish, the availability of billfish, and their vulnerability to fishing pressure.
The ecosystem in this region is very peculiar and dynamic. Sea height state, surface currents, and primary productivity (chlorophyl and water color) dictate the availability of billfish for catch-and-release fisheries.