With over 180 non-native aquatic species currently present in the Great Lakes and potential new invaders on the horizon, keeping track of the impacts and risks that these organisms pose is an ongoing challenge. The Great Lakes Aquatic Nonindigenous Species Information System (GLANSIS), a one-stop shop for information about aquatic nonindigenous species, hosts data on the historical and ongoing effects of aquatic organisms introduced to the region. Two NOAA Technical Memos serve as the underlying risk and impact assessments for the GLANSIS database and researchers recently completed important annual updates to these documents (TM-161c and TM-169c). These updates allow researchers to stay current on potential risk and impacts of these organisms to the ecosystem.

What are the GLANSIS tech memos?
NOAA Technical Memos are used for the timely documentation and communication of raw data, preliminary results of scientific studies, or interim reports that may not have received formal external peer reviews in the style of academic journal articles or manuscripts. These numbered publications are publically available online in PDF format, and serve as important research documentation and reference material.
The GLANSIS team updates two different tech memos every year by reviewing and synthesizing the scientific literature on invasive — or potentially invasive — aquatic species. The first, TM GLERL-161et seq., “An Impact Assessment of Great Lakes Aquatic Nonindigenous Species”, provides the updated impact assessments for nonindigenous species documented as reproducing and overwintering in the Great Lakes, focusing on their ecological, socio-economic, and beneficial impacts to the region. The second, TM GLERL-169 et seq., “A Risk Assessment of Potential Great Lakes Aquatic Invaders” documents species that have been identified as likely to become invasive if introduced to the Great Lakes region. The 2019 updates document the updated impact assessments for 89 of the 188 nonindigenous species (TM-161c) and four assessments were updated and eight new species were added for potential invasives (TM-169c).
Why are the tech memos updated every year, and why are they important?
The GLANSIS technical memos provide transparent, publicly-available documentation of the risk assessment process that underlies the species profiles in the database. Not only do they provide the summary information available in the website, they also share all the original sources and the details of the specific semi-quantitative analysis behind declaring particular species ‘high-impact’. New and improved data on aquatic invasive species is being published all the time, and documenting annual updates to risk and impact assessments helps to keep the GLANSIS database up-to-date and allows researchers to track the changes in the state of knowledge for specific species through the years. Each update takes a new look at how the latest data influences larger-scale patterns and trends. Unlike a website, where old versions are overwritten by the new, the technical memos provide a stable, citable reference point.
The GLANSIS tech memos can be read in full at the NOAA Great Lakes Environmental Research Lab’s publications page. To learn more about GLANSIS, check out https://www.glerl.noaa.gov/glansis/ and explore the site for yourself.