Cross-Matching VIIRS Boat Detections with Vessel Monitoring System Tracks in Indonesia

Abstract

A methodology had been proposed for cross-matching visible infrared imaging radiometer suite (VIIRS) boat detections (VBD) with vessel monitoring system (VMS) tracks. The process involves predicting the probable location of VMS vessels at the time of each VIIRS data collection with an orbital model. Thirty-two months of Indonesian VMS data was segmented into fishing and transit activity types and then cross-matched with the VBD record. If a VBD record is found within 700 m and 5 s of the predicted location, it is marked as a match. The cross-matching indicates that 96% of the matches occur while the vessel is fishing. Small pelagic purse seiners account for 27% of the matches. Other gear types with high match rates include hand line tuna, squid dip net, squid jigging, and large pelagic purse seiners. Low match rates were found for gillnet, trawlers, and long line tuna. There is an indication that VMS vessels using submersible lights can be identified based on consistently low average radiances and match rates under 45%. Overall, VBD numbers exceed VMS vessel numbers in Indonesia by a nine to one ratio, indicating that VIIRS detects large numbers of fishing boats under the 30 Gross Tonnage (GT) level set for the VMS requirement. The cross-matching could be used to identify “dark” vessels that lack automatic identification system (AIS) or VMS.

Sensing the Same Fishing Fleet with AIS and VIIRS: A Seven-Year Assessment of Squid Jiggers in FAO Major Fishing Area 41

“…Had a significant manipulation of transceivers occurred after 2012, when GFW started to compile massive AIS data, a manifest trace should be evident in this ratio. Thus, a potential manipulation of transceivers to game the system will alter GFW but not VIIRS-DNB radiance signal since the nature of jigger operation, using powerful lights at night, cannot be hidden to VIIRS-DNB [10]. A significant manipulation of AIS transceivers would bear a loss of the consistency between GFW and VIIRS-DNB signals reported here.…”

“…Our Figures 2 and 3 show features similar to those shown in Figure 2 of [20], although in their case the data of vessel presence were obtained from coastal authorities. The authors of [10] performed this exercise for fisheries in Indonesian waters on a vessel-to-vessel basis where data from the vessel monitoring system (VMS) of coastal authorities (rather than AIS from GFW) were compared with VIIRS-DNB information. They found a high match rate between VMS and VIIRS-DNB information when the gear, as it is our case, utilized high light power during the night.…”

“…Other sources of information can help extend the diagnosis from the internal coherence of AIS messages to consistency when comparing with independent data. Remote sensing is again useful to this aim, in particular for gear whose mode of operation makes it visible to satellite-borne radiometers [9,10]. This is the case of the jigger fleet since it uses powerful lights for night fishing [11,12].…”

“…One of VIIRS spectral channels is DNB (day/night band), specifically designed to capture low light levels during the night. VIIRS-DNB is sensitive enough to capture the light of some fishing vessels while they operate their gear at sea [9,10,12].…”

Application of a New Shore-Based Vessel Traffic Monitoring System Within San Francisco Bay

“…Vessel traffic monitoring systems are often used for maritime surveillance and traffic control in coastal areas (e.g., Wahab et al, 2016;Zhen et al, 2017) but can also be employed for environmental protection purposes. Monitoring vessel activity can help local management institutions assess compliance with protected area and/or fisheries regulations (Bergseth et al, 2015;Elahi et al, 2018;Elvidge et al, 2018;Longépé et al, 2018;Hsu et al, 2019;Kurekin et al, 2019). Many marine protected areas (MPAs) fail to meet thresholds for effective management due to staff and budget capacity (Gill et al, 2017).…”