3. Collect
3.3 Other considerations
Overview Introduction Standard procedures Other considerations Resources Results and next steps
It is well beyond the scope of this Salmon Monitoring Advisor website to create extensive advice for choosing specific data collection methods and considerations, especially given the extensive resources that are available scientific in fisheries literature and resource institution websites. But some additional considerations are noteworthy, which monitoring and field data collection practitioners should carefully consider since they can have a large bearing on the implementation, conduct and interpretation of monitoring programs.
Data considerations beyond your project area
The information and resources on this website primarily focus on monitoring design and data collection needed to estimate the status, condition, or trend of freshwater population variables, such as spawning escapement or juvenile production, within the study area. However, planning the design, data collection and analysis for a specific monitoring project must consider these same elements for 'external' projects that ultimately will be relied upon for contributing information needed to answer certain questions. Data that are key to making inferences from the project will be derived from other sources and the monitoring project leader must understand the availability, quality, and potential limitations of such data. These key externalities should be explicitly evaluated and incorporated at relevant steps in a monitoring project's design to maximize the chance that the project's objectives can be met. Also see Step 5 - Interpret data.
Harvest data
If a key indicator of the project's design is abundance of adult recruits prior to fishing, then spawning escapement estimates likely will be inadequate to assess population status and trends if the population is subject to fishery harvest or incidental mortality. Standard procedures have been developed for annually sampling catches in order to estimate abundance of adult recruits prior to the onset of fishing and properly allocating catches to their populations of origin. These procedures include taking samples from catches of coded-wire tags, fish scales, otoliths, genetic material, parasites, or other tissues to identify the spawning population of origin and the year in which those adult recruits were spawned. The resulting allocation of catches to populations of origin is a crucial step in reliably estimating annual productivity of groups of spawners or seaward-migrating juveniles and detecting spatial or temporal trends in productivity of particular populations that might be a conservation concern. For more information on harvesting salmon and its relevance to monitoring, click here.
Environmental data
The purpose of measuring a salmon population response variable often may be to evaluate factors that could be causing various responses, e.g., evaluating the effect of environmental conditions such as sea surface temperature, salinity, or marine prey abundance and distribution when used as explanatory variables in statistical models. For additional information on potential explanatory variables such as climate-induced environmental variables, please refer to 'Sources of environmental data'.
Safety, logistics and fish care
While the challenges of working in unpredictable and sometimes extreme aquatic environments are apparent, it cannot be overstated that the implementation of data collection projects for salmon populations should be very carefully considered and planned. The project operations plan should contain specific safety procedures. Further, when sampling salmonid populations, deleterious impacts to living resources need to be carefully avoided by use of proper fish sampling and handling techniques. These are practical elements in project operation plans that should not be overlooked. For the inexperienced, do not be afraid to consult experts that can advise about both the practical realities of working with live fish, collecting data in the field and also the real safety issues that should be anticipated and avoided.
Permit requirements
Various levels of government often have rules and regulations that must be followed to authorize activities associated with monitoring projects, from the standpoint of potential impacts on the fish populations and/or their physical environment. For example, the permits required to study populations in the U.S. that are listed under the Federal Endangered Species Act (ESA) are notable in this regard. But a variety of other environmental permitting requirements also are routinely involved for any specific project location - becoming familiar with these and planning for them in advance is an important operational need.
