Divers remove invasive sun coral around Brazil’s Cagarras Islands

What you need to know

• The report identifies two invasive sun coral species in Brazil: Tubastraea coccinea and T. tagusensis. Divers are removing colonies around Cagarras, within a protected archipelago near Rio de Janeiro. New reporting identifies an offshore oil platform as the work site and Brazilian biologist Adriana Gomes as part of the team. 125
• Brazil approved a national prevention, control and monitoring plan for sun coral in 2018. The official plan names both species and lists Cagarras among the places where they have been recorded. 2
• A multi-site study on Brazil’s coast found that repeated manual removal reduced sun coral cover to zero at its study sites. A single removal was sufficient at low-density sites, but outcomes differed with site conditions, including propagule pressure and invasion history. 3
• ICMBio guidance describes manual removal as a principal control method in natural areas. It recommends systematic repeat visits because tissue left on the substrate can regenerate. 4
• The available research supports removal as a useful control approach, not a guaranteed one-off solution. The current report does not establish how much coral has been removed at Cagarras or whether the work has reduced cover there. 134

Why this matters

The Cagarras operation addresses an invasive marine species already recorded at the site, while the wider evidence suggests that removal can reduce its cover. Follow-up matters: without repeat checks, residual coral tissue may regenerate, and outcomes from other sites cannot establish recovery at Cagarras. 234

What happens next

The report does not describe a monitoring schedule or results for the current operation. Repeat visits are recommended in ICMBio guidance, so information on removal levels and checks for regrowth would help show whether the approach is working at Cagarras. 14

What we know

• The report describes divers removing sun coral around the Cagarras Islands, a protected area near Rio de Janeiro. New reporting identifies an offshore oil platform as the work site and names Brazilian biologist Adriana Gomes as part of the team. 15
• Brazil’s official plan identifies two invasive Tubastraea species and records sun coral at Cagarras. 2
• Repeated manual removal reduced coral cover to zero at the sites in a multi-site study, although results differed by site. 3
• ICMBio guidance recommends repeat visits because tissue remaining after removal can regenerate. 4

What we don't know

• The report does not say how many colonies, or how much coral, has been removed in the current Cagarras effort. 1
• It does not describe what monitoring will assess regrowth or how often the removal sites will be revisited. 14
• There are no reported measurements showing whether native species or habitat conditions have changed at the specific Cagarras sites. 1
• The report’s estimate of the invasion’s spread along approximately 3,500 kilometres of coast is not accompanied in the supplied material by its evidence or method. 1

Read the reporting

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