How Functional Diversity Studies Inform Fishery Management and Allocate Resources

The Green River in Utah hosts a variety of avian, terrestrial, and aquatic species populations. (Credit: Bob Wick / Bureau of Land Management via Flickr CC BY-NC 2.0)

Understanding functional diversity amongst species in an ecosystem is a key component of managing fishery resources. The importance of maintaining native biodiversity cannot be overstressed, particularly when climate change and various land use stressors threaten fish populations globally.

Use of Functional Diversity Studies

While species diversity studies only consider the taxonomic component, functional diversity studies focus on the variability of species’ functional traits, as defined in a 2023 study published in Neotropical Ichthyology. Under limited conservation capabilities, such studies can help inform management and the allocation of resources.

According to a 2015 study published in the Brazilian Journal of Nature Conservation, functional diversity studies measure the ecological importance of species in a community and highlight how biodiversity affects specific ecosystem functions.

Such studies can contribute to a better understanding of different patterns, such as species occurrence, competitive abilities, community assembly, and the influence of biological communities on ecosystem functioning.

The focus on functional diversity studies varies depending on what is deemed an ecologically meaningful trait, varying based on the research focus.

Much like researchers will conduct population or distribution studies to inform stocking efforts (quantity and location) due to how costly the strategy is, functional diversity studies help inform management by highlighting key functions of species in the watershed.

Some of the most common traits researched according to the 2023 study were morphological traits, while ecological traits were the least used.

Morphological studies focus on the physical characteristics of fish and allow researchers to identify what traits are most successful in the system. Alternatively, ecological studies look more at the ecosystem and what conditions certain species favor.

As this relates to fishery management, a long-snouted, deepwater fish that already does well in the ecosystem may not need as much active management as a short-nosed, shallow-water fish that has been displaced into deeper waters due to an invasive species.

The study also found that functional studies were conducted more in streams and rivers, likely due to species-focused studies being easier in these environments rather than deeper and larger reservoirs.

Conclusion

While additional efforts like population studies, creel surveys, annual stocking, and water quality monitoring can be important components of long-term management, functional diversity studies are another tool fishery managers can use in order to understand the ecosystem better and allocate limited resources.