Dataset

DFO Pacific Inside North Hard Bottom Longline Surveys

OBIS Canada MeasurementOrFact Open in mapper Explore occurrences

The Inside North Hard Bottom Longline (HBLL) survey is one of a set of long-term and coordinated surveys that together cover most of the nearshore, hard-bottom habitat of coastal British Columbia. The other surveys are the Inside South HBLL survey, Outside North HBLL survey, and Outside South HBLL survey. The Inside North HBLL survey was first conducted in 2003, and repeated in 2004 and 2007. Starting in 2008, this survey has been repeated every second year, in alternate years to the Inside South HBLL survey, with the exception that no surveys were conducted in 2017. The survey was not impacted by the COVID-19 pandemic. The objective of these surveys is to provide fishery-independent abundance indices and associated biological data for the assessment of nearshore rockfishes and other groundfish species that live on untrawlable, hard bottom habitats. The surveys follow a random depth-stratified design and the sampling units are 2 km by 2 km blocks. The surveys use size 13/0 circle hooks, baited with frozen squid. The Inside North HBLL Survey is conducted by Fisheries and Oceans Canada (DFO) and takes place on the Canadian Coast Guard Research Vessel Neocaligus. This survey covers the northern portion of the inlets and protected waters east of Vancouver Island, including Johnstone Strait and Broughton Archipelago in Pacific Fishery Management areas (PFMAs) 12 and 13. The data provided include information about the annual survey trips and fishing events (tows/sets) that are part of this survey series, including the vessel name, dates, times, spatial coverage, gear details, and effort information. Catch information (total weight in kg or counts of individual specimens) is included from successful fishing events. Catches are identified to species or to the lowest taxonomic level possible. Most catches are weighed, but some are too small (“trace” amounts) or too large (e.g. very large Big Skate). Some catches were subsampled and biological data were collected from individual fish specimens, including length, sex, and weight information. Where age structures were collected and processed, fish ages have been included.

Citation: Cornthwaite M (2023). DFO Pacific Inside North Hard Bottom Longline Surveys. Version 3.0. Fisheries and Oceans Canada. Samplingevent dataset. https://doi.org/10.25607/krf8yo

Published: September 07, 2023 at 18:51

URL: http://ipt.iobis.org/obiscanada/resource?r=hbll-in-n

47,573
occurrence records
109,933
measurements and facts
113
taxa
71
species

Taxa

Missing and invalid fields

Field Missing Invalid
coordinateUncertaintyInMeters 47,573
100.0%
maximumDepthInMeters 382
0.8%
minimumDepthInMeters 509
1.1%

Quality flags

The OBIS data quality flags are documented at https://github.com/iobis/obis-qc.

Flag Dropped Records
DEPTH_EXCEEDS_BATH 28,713
60.4%
NO_DEPTH 382
0.8%

Measurement types

DNA derived data