Integrating vessel monitoring systems (VMS) data with daily catch data from logbooks to explore the spatial distribution of catch and effort at high resolution

Abstract

Vessel Monitoring Systems (VMS) automatically collect positional data from fishing vessels. The VMS data can be linked to catch data from logbooks to provide a census of spatially resolved catch and effort data. We explore and validate the most appropriate and practical method for integrating Irish VMS and logbook data. A simple speed rule is applied to identify VMS records that correspond to fishing activity. These data are then integrated with the catch data from the logbooks using date and vessel identifier. A number of assumptions were investigated and the resulting distribution maps of catch and effort appear to be unbiased. The method is illustrated with an example of a time-series of spatially explicit catch per unit effort estimates. The proposed method is relatively simple and does not require specialist software or computationally intensive methods. It will be possible to generalise this approach to similar data sets that are available within the EU and many other regions. Analysis of integrated VMS and logbooks data will allow fisheries data to be analysed on a considerably finer spatial scale that was possible in the past which opens up a range of potential applications.

The Spanish blackspot seabream (Pagellus bogaraveo) fishery in the Strait of Gibraltar: spatial distribution and fishing effort derived from a small-scale GPRS/GSM based fisheries vessel monitoring system

“…Apportioning landings data to fishing hauls allowed the spatial distribution of the catch to be mapped. However, allocating boat daily catches equally to fishing hauls makes the assumption that the catch rate is the same in all hauls for a given boat and day (Gerritsen and Lordan 2011).…”

Anthropogenic influence on sediment transport in the Whittard Canyon, NE Atlantic

“…The total records for the month of June (589) were 138 reduced to those fitting the criteria for trawling activity and recorded during the operational survey 139 period to Whittard Canyon (9-17 th June 2013). To fit the criteria (likely) for trawling activity, vessels 140 must be equipped with bottom trawling gear and be operating at ≤5 knots, a suitable threshold to 141 denote fishing activity (Gerritsen and Lordan, 2011 (Figure 2a …”

Record of anthropogenic impact on the Western Irish Sea mud belt

“…The system has been installed on all fishing vessels >24 m since January 2000 according to European Commission legislation, and on vessels >18 and >15 m since 2004and 2005, respectively (Gerritsen and Lordan, 2011. Gerritsen and Lordan (2011) and Gerritsen et al (2013) provide further information on VMS methods of analysis and processing. VMS data have been previously used to assess the extent and frequency of the impact by mobile fishing gear (Puig et al, 2012;Gerritsen et al, 2013).…”