Pacific Halibut Length-Weight Relationships

Pacific Halibut Length-Weight Relationships and Calculator

This page contains links to the IPHC’s revised Pacific Halibut Length-Net Weight Tables and the IPHC Pacific Halibut Length-Weight Calculator.

The current IPHC commercial Pacific halibut sampling program and the IPHC Fishery-Independent Setline Survey (FISS) weight sampling provide us with two independent data sources to use in estimating contemporary length-net weight relationships. While the FISS data are typically collected in a spatially comprehensive manner within each IPHC Regulatory Area, they are temporally restricted to the May-September summer period. Conversely, commercial samples are collected throughout the fishing season, but may be more geographically limited due to the concentration of fishing effort in the most productive habitat.

As proposed at the 19th Session of the IPHC Scientific Review Board (SRB019) (Webster 2021), our approach is to combine data from the commercial sampling with that from the FISS sampling in order to estimate length-net weight relationships that are as broadly applicable as possible. Data from the most recent three years (2019-21) were used in the modelling. Webster (2021) fitted models to commercial and FISS data by area and year, showing general temporal consistency in the estimated length-net weight relationships, but variability among relationships across IPHC Regulatory Areas. We have therefore estimated a revised relationship for each IPHC Regulatory Area using the combined data from 2019-21.

For the complete and detailed analysis please review the following document from the 98th Session of the IPHC Annual Meeting (AM098):

Document Title PDF Availability
IPHC-2022-AM098-INF07 Revision of the IPHC length-weight relationship (R. Webster & I. Stewart) PDF icon 23 Jan 2022

To instantly estimate the weight of a Pacific halibut by length and IPHC Regulatory Area utilize the IPHC Pacific Halibut Length-Weight Calculator below. Options for different length (cm or in) and weight (kg or lb) units are available as well as weight outputs (Net or Round). 

 IPHC Pacific Halibut Length-Weight Calculator

This calculator produces an estimate of the weight (net or round) of a Pacific halibut from its length based on metric or Imperial units. Estimates are calculated using the revised IPHC length-weight relationships as previously discussed and seen below. Any small differences with tabulated results are due to rounding of parameter estimates.

Each tab below contains IPHC Regulatory Area-specific figures displaying length-net weight relationships estimated from 2019-21 commercial and FISS sampling data compared with the historical length-net weight relationship and the corresponding length-net weight tables in metric and imperial units. 

IPHC Regulatory Area 2A

iphc-2022-lwt-2a.jpg

Length-net weight relationship estimated from 2019-21 commercial and FISS sampling data (dashed line) compared with the historical length-net weight relationship (solid blue line) for IPHC Regulatory Area 2A (left panel). The right panel shows the ratio of the predicted weights from the revised and historical relationships: values less than the dashed line at 100% mean the revised relationship predicts lighter Pacific halibut than the historical relationship.

IPHC-2022-LWT-2AMetric Length-net weight table for IPHC Regulatory Area 2A (metric, 71-230 cm). PDF icon 23 Jan 2022
IPHC-2022-LWT-2AImperial Length-net weight table for IPHC Regulatory Area 2A (Imperial, 22.5-92 inches). PDF icon 23 Jan 2022

IPHC Regulatory Area 2B

iphc-2022-lwt-2b.jpg

Length-net weight relationship estimated from 2019-21 commercial and FISS sampling data (dashed line) compared with the historical length-net weight relationship (solid blue line) for IPHC Regulatory Area 2B (left panel). The right panel shows the ratio of the predicted weights from the revised and historical relationships: values less than the dashed line at 100% mean the revised relationship predicts lighter Pacific halibut than the historical relationship.

IPHC-2022-LWT-2BMetric Length-net weight table for IPHC Regulatory Area 2B (metric, 71-230 cm). PDF icon 23 Jan 2022
IPHC-2022-LWT-2BImperial Length-net weight table for IPHC Regulatory Area 2B (Imperial, 22.5-92 inches). PDF icon 23 Jan 2022

IPHC Regulatory Area 2C

iphc-2022-lwt-2c.jpg

Length-net weight relationship estimated from 2019-21 commercial and FISS sampling data (dashed line) compared with the historical length-net weight relationship (solid blue line) for IPHC Regulatory Area 2C (left panel). The right panel shows the ratio of the predicted weights from the revised and historical relationships: values less than the dashed line at 100% mean the revised relationship predicts lighter Pacific halibut than the historical relationship.

IPHC-2022-LWT-2CMetric Length-net weight table for IPHC Regulatory Area 2C (metric, 71-230 cm). PDF icon 23 Jan 2022
IPHC-2022-LWT-2CImperial Length-net weight table for IPHC Regulatory Area 2C (Imperial, 22.5-92 inches). PDF icon 23 Jan 2022

IPHC Regulatory Area 3A

iphc-2022-lwt-3a.jpg

Length-net weight relationship estimated from 2019-21 commercial and FISS sampling data (dashed line) compared with the historical length-net weight relationship (solid blue line) for IPHC Regulatory Area 3A(left panel). The right panel shows the ratio of the predicted weights from the revised and historical relationships: values less than the dashed line at 100% mean the revised relationship predicts lighter Pacific halibut than the historical relationship.

IPHC-2022-LWT-3AMetric Length-net weight table for IPHC Regulatory Area 3A (metric, 71-230 cm). PDF icon 23 January 2022
IPHC-2022-LWT-3AImperial Length-net weight table for IPHC Regulatory Area 3A (Imperial, 22.5-92 inches). PDF icon 23 January 2022

IPHC Regulatory Area 3B

iphc-2022-lwt-3b.jpg

Length-net weight relationship estimated from 2019-21 commercial and FISS sampling data (dashed line) compared with the historical length-net weight relationship (solid blue line) for IPHC Regulatory Area 3B (left panel). The right panel shows the ratio of the predicted weights from the revised and historical relationships: values less than the dashed line at 100% mean the revised relationship predicts lighter Pacific halibut than the historical relationship.

IPHC-2022-LWT-3BMetric Length-net weight table for IPHC Regulatory Area 3B (metric, 71-230 cm). PDF icon 23 Jan 2022
IPHC-2022-LWT-3BImperial Length-net weight table for IPHC Regulatory Area 3B (Imperial, 22.5-92 inches). PDF icon 23 Jan 2022

IPHC Regulatory Area 4A

iphc-2022-lwt-4a.jpg

Length-net weight relationship estimated from 2019-21 commercial and FISS sampling data (dashed line) compared with the historical length-net weight relationship (solid blue line) for IPHC Regulatory Area 4A (left panel). The right panel shows the ratio of the predicted weights from the revised and historical relationships: values less than the dashed line at 100% mean the revised relationship predicts lighter Pacific halibut than the historical relationship.

IPHC-2022-LWT-4AMetric Length-net weight table for IPHC Regulatory Area 4A (metric, 71-230 cm). PDF icon 23 Jan 2022
IPHC-2022-LWT-4AImperial Length-net weight table for IPHC Regulatory Area 4A (Imperial, 22.5-92 inches). PDF icon 23 Jan 2022

IPHC Regulatory Area 4B

iphc-2022-lwt-4b.jpg

Length-net weight relationship estimated from 2019-21 commercial and FISS sampling data (dashed line) compared with the historical length-net weight relationship (solid blue line) for IPHC Regulatory Area 4B (left panel). The right panel shows the ratio of the predicted weights from the revised and historical relationships: values less than the dashed line at 100% mean the revised relationship predicts lighter Pacific halibut than the historical relationship

IPHC-2022-LWT-4BMetric Length-net weight table for IPHC Regulatory Area 4B (metric, 71-230 cm). PDF icon 23 Jan 2022
IPHC-2022-LWT-4BImperial Length-net weight table for IPHC Regulatory Area 4B (Imperial, 22.5-92 inches). PDF icon 23 Jan 2022

IPHC Regulatory Area 4CDE

iphc-2022-lwt-4cde.jpg

Length-net weight relationship estimated from 2019-21 commercial and FISS sampling data (dashed line) compared with the historical length-net weight relationship (solid blue line) for IPHC Regulatory Area 4CDE (left panel). The right panel shows the ratio of the predicted weights from the revised and historical relationships: values less than the dashed line at 100% mean the revised relationship predicts lighter Pacific halibut than the historical relationship.

IPHC-2022-LWT-4CDEMetric Length-net weight table for IPHC Regulatory Area 4CDE (metric, 71-230 cm). PDF icon 23 Jan 2022
IPHC-2022-LWT-4CDEImperial Length-net weight table for IPHC Regulatory Area 4CDE (Imperial, 22.5-92 inches). PDF icon 23 Jan 2022