As divers in Malta, we’ve all noticed the thinning numbers of sea urchins—our local rizzi—over the last few years. While the national moratorium on harvesting is one way to protect them (if really enforced), a breakthrough at Aquatic Resources Malta (ARM) is offering a more proactive solution to bring sea urchins back to the wild.
Lab-Grown Breakthrough
Scientists at the Fort San Luċjan lab in Marsaxlokk have successfully spawned approximately 100,000 larval sea urchins. This project is a critical “proof of concept” aimed at restocking our reefs, which have been hit hard by climate change, rising sea temperatures, and over fishing.
According to researchers in the wild, the survival rate for sea urchin eggs is incredibly low—often less than 1%. However, researchers Adrian Love and Andrew Mallia are seeing much higher success rates in the lab. These larvae have already survived the most dangerous first two months of their life cycle and are preparing for their next phase.
From Lab to Reef
The journey from microscopic larvae to the spiny creatures we see on a night dive is a slow one:
- Metamorphosis: After the first month, larvae settle on rock beds and begin their transformation.
- Slow Growth: Urchins grow at a rate of just 1–2cm per year.
- The Release: ARM plans to release a batch of several hundred juvenile urchins into the wild in late 2026.
The Moratorium Extension
This lab work couldn’t come at a more vital time. While we previously reported on the initial 2023 harvesting ban, the government has officially extended the moratorium until July 7, 2027.
The extension follows scientific monitoring across 10 sites which showed that while 60% of areas are seeing a recovery—specifically in specimens sized 2–4cm—growth is not yet uniform across the islands. This extra time is essential to ensure that the lab-grown “rizzi” have a stable environment to thrive in once they are released.
Why It Matters for Divers
Sea urchins are the “gardeners” of our reefs, keeping algae in check and supporting at least 18 different fish species. While they are resilient, they are increasingly vulnerable to diseases caused by higher salinity and warming waters.
Next time you’re gearing up at Cirkewwa or Wied iż-Żurrieq, keep an eye out for those small 2cm juveniles—they are the proof that our conservation efforts are working.
References:
- “Watch: Hope for lab-grown sea urchins grows,” Times of Malta, December 2025. Original Article.
- “Moratorium on sea urchin collection extended until 2027,” Government of Malta Press Release, July 2025.
- “Sea Urchin harvesting moratorium – fines starting at €500!” Divinginfo.mt.