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<DIV STYLE="text-align:Left;"><DIV><DIV><P STYLE="margin:0 0 0 0;"><SPAN>Data source:</SPAN></P><P STYLE="margin:0 0 0 0;"><SPAN /></P><P STYLE="margin:0 0 0 0;"><SPAN>PHMA longline </SPAN><SPAN>surveys</SPAN></P><P STYLE="margin:0 0 0 0;"><SPAN /></P><P STYLE="margin:0 0 0 0;"><SPAN>Methods summary:</SPAN></P><P STYLE="margin:0 0 0 0;"><SPAN /></P><P STYLE="margin:0 0 0 0;"><SPAN>Fish diversity was calculated from CPUE (count/hook/hr) </SPAN><SPAN>from </SPAN><SPAN>Pacific Halibut Management Association (PHMA) surveys. PHMA surveys are standardized, depth-stratified random longline surveys that are carried out at depths of 20–260 m. All species caught are weighed or counted and identified to the lowest possible taxonomic level. Data was extracted from DFO's GFBio database on 18 April 2017, limiting the query to records quality-tagged as "fully usable". The PHMA dataset spans August 2006 - August 2016 and includes records taken in the months of August and September. Shannon Diversity (H') was calculated from CPUE </SPAN><SPAN>of fish species </SPAN><SPAN>using the diversity function in the R package ‘vegan’.</SPAN></P><P STYLE="margin:0 0 0 0;"><SPAN /></P><P STYLE="margin:0 0 0 0;"><SPAN /><SPAN>Shannon diversity values were used to detect hotspots of diversity within coastal areas using the Getis-Ord G* tool. The G* statistic represents the local neighbourhood sum compared proportionally to the sum of all features in the study area. When the local sum is significantly different from the expected sum, then that site is identified as a hotspot (Gi_Bin>0), a cold spot (Gi_Bin<0), or neutral (Gi_Bin=0). A 10 km distance value was used as the neighbourhood size. The false discovery rate correction was applied, which accounts for multiple testing and spatial dependence. </SPAN><SPAN>Absolute Gi_Bin values of 1, 2, and 3 correspond to 90, 95, and 99% confidence, respectively. </SPAN></P><P STYLE="margin:0 0 0 0;"><SPAN /></P><P STYLE="margin:0 0 0 0;"><SPAN>Using the Minimum Bounding Geometry Tool, convex hull polygons were drawn around groups of hotspot points (confidence ≥90%) containing 10 or more points. The resulting polygons were then buffered by 1 km and manually edited where needed to </SPAN><SPAN>exclude any large </SPAN><SPAN>areas </SPAN><SPAN>of </SPAN><SPAN>the polygons that did not include hotspot points.</SPAN></P><P STYLE="margin:0 0 0 0;"><SPAN /></P><P STYLE="margin:0 0 0 0;"><SPAN>This layer was reviewed as part of a Canadian Science Advisory Secretariat (CSAS) regional peer review process on Nov 1-2, 2017 (Rubidge et al. 2018</SPAN><SPAN /><SPAN>).</SPAN></P><P STYLE="margin:0 0 0 0;"><SPAN /></P><P STYLE="margin:0 0 0 0;"><SPAN>Date Represented: 200</SPAN><SPAN>6</SPAN><SPAN>-2016</SPAN></P><P STYLE="margin:0 0 0 0;"><SPAN>Date Updated: Nov 2017</SPAN></P><P STYLE="margin:0 0 0 0;"><SPAN /></P><P STYLE="margin:0 0 0 0;"><SPAN>References:</SPAN></P><P STYLE="margin:0 0 0 0;"><SPAN>Rubidge, E., Nephin, J., Gale, K.S.P., and Curtis, J. 2018. Reassessment of the Ecologically and Biologically Significant Areas (EBSAs) in the Pacific Northern Shelf Bioregion. DFO Can. Sci. Advis. Sec. Res. Doc. 2018/053. xii + 97 p.</SPAN></P></DIV></DIV></DIV> |