bsnouffer
commented
4 years ago Jason and I have relooked at this and come up with way to consolidate these. It involves a slight tweak to use more understandable terms. Jason: "I think the real distinction is whether the survey is opportunistic-- such as one that uses fishery-dependent information to try and come up with an index-- vs. a scientifically designed (usually fishery-independent) survey. What can get confusing in the fishery-dependent vs independent comparison is when fishing vessels are hired to do a scientific design. I consider that a scientific survey, not a fishery-independent survey, but people could answer the question that it is a CPUE survey because it came from fishers."
Proposed New Questions
(current questions below)
What time series exists of scientifically designed (e.g., fishery-independent) surveys of relative or absolute abundance? This question refers to scientifically designed data collection programs of or surveys of abundance, regardless of whether scientists or fishers collect the data. “Relative abundance” measures only a subset of the population, and is often linked to an effort or area measure (e.g., #/m^2). “Absolute abundance” assumes a total estimate of all animals for the assessed population (in numbers or biomass).
0: Absent 1: Snapshots/intermittent/inconsistent reporting 2: Partial time series that does not cover major or peak years of removals 3: Partial time series that cover major/peak years of removals 4: Full time series since fishing began
What time series exists of opportunistic (e.g., fishery-dependent) abundance indices? This refers to data collected without the initial intent of measuring abundance. A common example is catch-per-unit-effort (CPUE) information based on data collected from the fishery then standardized to represent abundance.
0: Absent 1: Snapshots/intermittent/inconsistent reporting 2: Partial time series that does not cover major or peak years of removals 3: Partial time series that cover major/peak years of removals 4: Full time series since fishing began
Criteria: The current questions are only used for criteria and always together as a group in multiple "or" criteria groups (318, 3356, 3358, 323). Questions would stay in all the same multiple "or" criteria groups that they currently are in, only adjustment would be that there are two abundance time series questions instead of three. The one exception is that the current fishery-independent question is a criteria for Ecosystem Threshold Analysis. The scientific design question will be the new criteria for that option.
For inputting the questions into FishPath: About 3/4 of the fishery questionnaires have different answers for the current two fishery-dependent questions (263, 275). Given that, I propose deleting both questions and inputting the opportunistic (fishery-dependent) question as a new question. This will force users to answer it under the new definition and avoid us having to choose between which fishery-dependent question to keep. Deleting the old fishery-independent question (281) and inputting the scientifically designed question as a new question would also make sense, as some of the time series that would previously have fallen under 275 (other fishery-dependent data) now would fit here. However, these all 3 current questions are grouped wherever they are used as criteria (except for Ecosystem Threshold Analysis) so it would likely not make a big impact on the results shown.
Current Questions
263: What time series exists of catch-per-unit-effort data? This question refers to any measure of catch (e.g., numbers, biomass) by effort (e.g., time fished), and can be used to measure density or relative abundance.
0: Absent 1: Snapshots/intermittent/inconsistent reporting 2: Partial time series that does not cover major or peak years of removals 3: Partial time series that cover major/peak years of removals 4: Full time series since fishing began
275: Is there a fishery-dependent time series, in addition to, or instead of, catch-per-unit-effort, CPUE, of relative or absolute abundance data? This refers to data collected by fishers that use their own gear and/or vessel in the absence of a scientifically designed data collection program. “Relative abundance” expresses abundance as some percentage of a reference value, usually the unfished abundance. “Absolute abundance” expresses abundance in terms of numbers or kilograms, or a density. As an example, scallop fishers may conduct their own, approved, pre-season survey of known scallop beds, to ascertain their condition and identify where their efforts will be dedicated during the fishing season.
0: Absent 1: Snapshots/intermittent/inconsistent reporting 2: Partial time series that does not cover major or peak years of removals 3: Partial time series that cover major/peak years of removals 4: Full time series since fishing began
281: What time series exists of fishery-independent relative or absolute abundance data? This question refers to scientifically designed data collection programs (it does not matter who undertakes the sampling). “Relative abundance” measures only a subset of the population, and is often linked to an effort or area measure. “Absolute abundance” assumes a total estimate of all animals for the assessed population (in numbers or biomass).
0: Absent 1: Snapshots/intermittent/inconsistent reporting 2: Partial time series that does not cover major or peak years of removals 3: Partial time series that cover major/peak years of removals 4: Full time series since fishing began
shcaba
jonowilson
This came up when updating the wording to answers to the time-series data questions (in issue #168).
We had planned on removing the CPUE question as redundant with the fishery dependent survey question. However, in the meantime the fishery dependent survey question was updated to "Is there a fishery-dependent time series, in addition to, or instead of, catch-per-unit-effort, CPUE, of relative or absolute abundance data?" However both trigger the same criteria in all cases (they are only found in "OR" criteria) making one of them redundant. Jason has proposed combining them into one question as proposed above. Change fishery-dependent wording to: "What time series exists of fishery-dependent (e.g., catch-per-unit-effort or area) abundance data? This refers to data collected by fishers that use their own gear and/or vessel in the absence of a scientifically designed data collection program.