The following story originally appeared on the website for W&M’s Batten School & VIMS. – Ed.

Algae don’t get the credit or attention they deserve. They are responsible for much of the oxygen we breathe, play pivotal roles in the habitats in which they live and are culturally important in coastal communities worldwide, yet there are still many things that we don’t understand about these seemingly simple organisms.

Renowned phycologist Stacy Krueger-Hadfield was part of a cluster hire of five faculty members who joined William & Mary’s Batten School & VIMS in 2023-2024, and she now serves as associate professor and assistant director of the Eastern Shore Laboratory (ESL) in Wachapreague, Virginia.

Within the last year, she and her colleagues, including students in her research program, have published 15 articles in scientific journals related to algae. However, she and many of her fellow phycologists believe there are fundamental challenges that their field must overcome to unlock many of the remaining algal secrets.

Last summer, Krueger-Hadfield was invited to a workshop with other Virginia phycologists focused on networking and advancing their field. These initial discussions at George Mason’s Potomac Environmental Research and Education Center led to a perspective paper in the Journal of Phycology outlining a road map to expanding our understanding of algae titled “The importance of integrating phycological research, teaching, outreach, and engagement in a changing world.”

“There are so many critical gaps in our knowledge of algal biology and ecology. Algae themselves are one of the worst defined groups of organisms with representatives found across the tree of life,” said Krueger-Hadfield, who served as the senior and co-corresponding author on the paper with colleagues, including workshop organizer Rosalina Stancheva Christova from George Mason University.

“For example, we classify animals in one group and mushrooms in another, but animals are more closely related to mushrooms than some algae are to each other. To add insult to injury, we are essentially separated by a common language in which terminology is not necessarily shared or used in the same way, slowing collective progress.”

The authors emphasized the need for a multidisciplinary approach to addressing global challenges involving algae and aquatic ecosystems. They focused on several main points, including the relevance and potential of algae in contributing to environmental and societal solutions; the need for stronger connections between research and education to prepare future scientists; the importance of outreach and education in fostering public awareness; solving complex problems in algal systems through interdisciplinary collaborations; adapting to a rapidly changing world in regard to technological advancement as well as climate change; and actionable strategies for enhancing the field’s impact, such as industry partnerships, community-based projects and the development of policy frameworks acknowledging the importance of algae.

Algae are far more than pond scum. They have the potential to play pivotal roles in addressing climate change, biodiversity loss, pollution, and other pressing issues such as the development of biofuels, biodegradable replacements for plastics and sustainable food sources. In order to realize any of this, Krueger-Hadfield argues that we need a better understanding of the different processes controlling algal reproduction, which may also carry the potential to unlock key mysteries about life.

Why should we care about algae?

In another perspective paper published in May 2024, Krueger-Hadfield highlighted ambiguity in the mechanisms driving sexual and asexual reproduction. She noted an alarming lack of data about the population genetics of most algae, which is essential to determining the relative frequency of sexual versus asexual reproduction.

Many of the recommendations put forward by Krueger-Hadfield and her colleagues are aimed at establishing a base of knowledge that lengthens the strides of future researchers. While things like population genetic studies and DNA barcoding of algal species require significant investments, technological resources and theoretical understanding, other recommendations simply require networking and collective agreement among the field.

“We can’t see algae reproduce, so we need to use population genetics to figure out how genes move across generations and to explore modes of reproduction and adaptations to environmental factors,” said Krueger-Hadfield. “Without a concerted effort to collect this data, we will struggle to forecast the impacts of climate change on algae or develop algal-based solutions to societal problems.”

In fact, algae exhibit a wide range of reproductive modes, which can either facilitate or potentially hinder their ability to adapt and evolve in response to environmental changes. While many assume sexual reproduction enhances genetic diversity, it doesn’t always. Likewise, fragmentation and other modes of asexual reproduction may be favored for rapid colonization of new habitats.

This reproductive adaptability was demonstrated in a study published by Krueger-Hadfield and her colleagues that examined the spread of an invasive green alga, Avrainvillea lacerata, or leather mudweed, on O’ahu, Hawai’i. The researchers, including an MS student in her lab as the first author, demonstrated that A. lacerata spread predominantly by vegetative growth. This is not unlike some flowering plants, where the individual continues to spread laterally getting bigger and bigger. Previous field observations suggested this was occurring, and this was supported with the use of population genetic analyses. However, the scientists also discovered evidence of multiple sets of chromosomes, or polyploidy. This complicates population genetic analyses, but polyploidy can promote environmental tolerance and genetic resilience in the absence of sexual reproduction.

“By identifying these traits, environmental managers can develop strategies to help limit the spread of invasive species such as leather mudweed,” said Krueger-Hadfield. “For example, we met with members of Malama Maunalua – a community-based nonprofit – that is trying to restore the Maunalua Bay on O’ahu where we sampled leather mudweed. We shared our results, which may influence how they remove this alga due to its ability to spread through fragmentation.”

Establishing a path for future success

“With the breadth of organisms that are collectively known as algae, we have issues with language and jargon that make it difficult to apply discoveries from one area to another,” noted Krueger-Hadfield, who resorted to developing a flow chart incorporating synonyms for terminology related to algal reproduction when reviewing existing literature. “We have a lot to gain from simply coming together and agreeing on ways in which we can add structure to our field to better facilitate information sharing.”

Krueger-Hadfield also emphasizes the need to engage students in meaningful research experiences that demonstrate the importance of algae in a variety of ecosystems. This approach was exemplified in a trio of studies (1,2,3) documenting the dispersion of freshwater red algae found in rivers and streams in the Eastern U.S. and Great Lakes. Carried out by Krueger-Hadfield and students at her former institution, the University of Alabama at Birmingham, the research was the first to document the population genetics of these algae that can serve as important bellwethers for the monitoring of pollutants.

“Algae are critical constituents in aquatic environments with benefits to people and communities. Students play an important role in facilitating this research and engaging the public in relevant ways,” said Krueger-Hadfield.

Krueger-Hadfield has carried her educational focus to the Batten School of Coastal & Marine Sciences, where she continues to look for ways to engage students of all levels in phycology. Now one of the school’s most popular undergraduate marine science field courses incorporates a phycological component, and she is also in discussions with academic administrators about the possibility of expanded course offerings in phycology at the ESL. Looking ahead, Krueger-Hadfield’s lab is planning studies on algal flora from the Mid-Atlantic all the way to the Antarctic Peninsula.

“The Batten School & VIMS has a unique focus on coastal and marine ecosystems in which algae are critical components. With strong philanthropic support and an expanding focus on academics and global impact, I’m optimistic about future opportunities to make important scientific contributions while mentoring new generations of scientists who can help unlock algae’s true potential,” said Krueger-Hadfield.