Skip to main content
U.S. flag

An official website of the United States government

Invasive corallimorpharians at Palmyra Atoll National Wildlife Refuge are no match for lye and heat

November 10, 2022

Invasive marine species are well documented but options to manage them are limited. At Palmyra Atoll National Wildlife Refuge (Central North Pacific), native invasive corallimorpharians, Rhodactis howesii, have smothered live native corals since 2007. Laboratory and field trials were conducted evaluating two control methods to remove R. howesii overgrowing the benthos at Palmyra Atoll (Palmyra): 1) paste mixed with chlorine, citric acid, or sodium hydroxide (NaOH), and 2) hot water. Paste mixed with NaOH had the most efficacious kill in mesocosm trials and resulted in > 90% kill over a 98 m² area three days after treatment. Hot water at 82°C was most effective in mesocosms; in the field hot water was less effective than paste but still resulted in a kill of ca. 75% over 100 m² three days after treatment. Costs of paste and heat (excluding capital equipment and costs of regulatory approval should this method be deployed large scale) were $70/m² and $59/m² respectively. Invasive R. howesii currently occupy ca 5,800,000 m² of reef at Palmyra with ca. 276,000 m² comprising heavily infested areas. Several potential management strategies are discussed based on costs of treatment, area covered, and the biology of the invasion. The methods described here expand the set of tools available to manage invasive species in complex marine habitats.

Publication Year 2022
Title Invasive corallimorpharians at Palmyra Atoll National Wildlife Refuge are no match for lye and heat
DOI 10.3391/mbi.2022.13.4.02
Authors Thierry M. Work, Renee Breeden, Robert Rameyer, Vernon Born, Tim Clark, Jeremy Rainal, Chris Gillies, Julia Rose, Alex Wegmann, Stefan Kropidlowski
Publication Type Article
Publication Subtype Journal Article
Series Title Management of Biological Invasions
Index ID 70238336
Record Source USGS Publications Warehouse
USGS Organization National Wildlife Health Center