Sponge bleach in New Zealand: Record death by heat wave

Sponge bleach in New Zealand: Record death by heat wave

Mass bleaching of the sponges: An alarming sign for the New Zealand's Navy Ecosystem

in New Zealand, a worrying phenomenon occurred that has far -reaching effects on the marine environment. Studies have shown that one of the largest known sponge bleach took place in Fiordland in 2022. The affected sponge, Cymbastella Lamellata, suffers from an unprecedented decline in its population along a coastline of around 1,000 kilometers.

Scope and effect of the sponge bleach

Researchers estimate that around 66 million sea sponges are affected. This development has caused almost 50 percent to reduce the sponge population. James Bell, marine biologist at the TE Herenga Waka - Victoria University of Wellington, emphasizes the gravity of the situation: "This was not only the largest sponge bleach worldwide, but also the severe siebenburisel among sponges that has ever been documented."

Insight into the causes: heat wave and temperature rise

The bleach occurred during an exceptionally long heat wave that lasted 259 days and led to the water temperatures up to 4.4 degrees Celsius above average. This temperature increase significantly influenced the color of the sponges, which previously had a dark brown and now assumed a pale white. The study shows that about 20 percent of the sponges in this region are fully exploited, 75 percent suffered from partial pale and only 5 percent remained unaffected.

The role of the symbioses and future perspectives

sponges enter symbioses with different organisms, including pebbles, crustaceans and microorganisms. These relationships are crucial for the survival of sponges, especially in stressful environments. When the sponges lose their pebbles that usually give them their color, they not only lose their appearance, but also potentially important quality of life. However, researchers are still unsure whether this bleach leads directly to the death of the sponges or whether they become more susceptible to predators because their visibility increases.

Outlook on the future of marine biodiversity

Despite the alarming developments, there are signs that some sponges can recover from the bleach. Bell is optimistic that sponges may be able to adapt to the warming water temperatures. In view of the increasing heat waves in the sea, this ability could be crucial to preserve biodiversity in the oceans in the long term. The effects on the marine life are considered considerably by the scientists, so it is important to carefully observe developments.