Interdisciplinary Science Approach for Harmful Algal Blooms (HABs) and Algal Toxins—A Strategic Science Vision for the U.S. Geological Survey

Circular 1520
By: , and 


Executive Summary

Algal blooms in water, soils, dusts, and the environment have captured national attention because of concerns associated with exposure to algal toxins for humans and animals. Algal blooms naturally occur in all surface-water types and are important primary producers for aquatic ecosystems. However, excessive algae growth can be associated with many harmful effects ranging from aesthetic to toxicity concerns, so this excessive growth is commonly called a harmful algal bloom (HAB).

Ecological imbalances that can lead to excessive algal growth, such as increased nutrient availability to waterbodies from natural and anthropogenic sources, are well documented in scientific literature. On the other hand, fundamental scientific understandings of environmental causes and controls leading to algal toxin production, environmental exposures, and adverse health outcomes for humans and animals could benefit from more attention by U.S. Geological Survey (USGS) scientists. Understanding when, why, and how the toxin is produced by individual algal cells or communities and why the toxin is released to the surrounding waterbody requires fundamental research to determine a toxin’s role, whether it provides competitive advantage or if other potential reasons exist for toxin production and release, such as secretions from otherwise benign biological processes. This research will require groundbreaking scientific discovery about underlying biologic and abiotic (non-living) processes commonly complicated by local variation in land use, microbial species composition, and ecosystem structure of the surrounding watershed.

Although underlying processes by which HABs form may be similar from one waterbody to another, individual waterbodies may be controlled by local factors for HAB development and toxin production that are unique to the watershed. Consequently, many fundamental science gaps exist that prevent informed mitigation and prevention of toxic HAB events. There are also gaps in understanding local conditions that control algal growth unique to specific watersheds. Addressing these science gaps is needed to inform evidence-based decisions that protect human and animal health and that reduce recreational and socioeconomic losses.

Suggested Citation

Christensen, V.G., Crawford, C.J., Dusek, R.J., Focazio, M.J., Fogarty, L.R., Graham, J.L., Journey, C.A., Lee, M.E., Larson, J.H., Stackpoole, S.M., Mazzei, V., Pindilli, E.J., Rattner, B.A., Slonecker, T., McSwain, K.B., Reilly, T.J., and Lopez, A.E., 2024, Interdisciplinary science approach for harmful algal blooms (HABs) and algal toxins—A strategic science vision for the U.S. Geological Survey: U.S. Geological Survey Circular 1520, 39 p.,

ISSN: 2330-5703 (online)

Table of Contents

  • Acknowledgments
  • Executive Summary
  • Chapter 1. Introduction
  • Chapter 2. Data Gaps, Capabilities and Expertise, and Opportunities for Algal Bloom and Algal Toxin Monitoring and Research Activities
  • Chapter 3. Vision for Interdisciplinary USGS HAB Science
  • References Cited
  • Glossary
  • Appendix 1
Publication type Report
Publication Subtype USGS Numbered Series
Title Interdisciplinary science approach for harmful algal blooms (HABs) and algal toxins—A strategic science vision for the U.S. Geological Survey
Series title Circular
Series number 1520
DOI 10.3133/cir1520
Year Published 2024
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Earth Resources Observation and Science (EROS) Center, Kansas Water Science Center, National Wildlife Health Center, New Jersey Water Science Center, New York Water Science Center, South Atlantic Water Science Center, Upper Midwest Water Science Center, Toxics Substances Hydrology Program
Description Report: vi; 39 p.; Appendix
Online Only (Y/N) Y
Google Analytic Metrics Metrics page
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