Investigation into Pink Substance on Tasmanian Beaches
Tasmanian authorities are investigating the presence of a pink-tinged substance observed on several beaches, including Randalls Bay, Little Roaring Beach, and Little Taylors Bay. Preliminary assessments suggest it may be an algal bloom.
Algal Bloom Characteristics and Occurrence
The Department of Natural Resources and Environment Tasmania has collected samples for analysis. A spokesperson stated that algal blooms are natural phenomena resulting from shifts in nutrients, temperature, rainfall, or light conditions. They are sometimes referred to as 'red tides' or 'pink tides' due to the water coloration they can produce. While not all algal blooms are harmful, many species contribute to the marine food web. Noctiluca scintillans, a marine phytoplankton, is frequently identified as the cause of such phenomena in Tasmanian waters, known for its bioluminescent properties at night.
The occurrence of algal blooms has increased in recent years, a trend attributed partially to climate change and pollution contributing to nutrient enrichment in marine environments. Dinoflagellates, a type of phytoplankton, can experience rapid population growth during a bloom, potentially disrupting ecosystems. These events can intensify under favorable conditions, and in severe cases, may lead to the suffocation or death of marine life, providing additional nutrients for the bloom.
Previous Incidents and Potential Effects
A significant algal bloom occurred recently along South Australia's southern coastline, reportedly affecting thousands of square kilometres. This event was associated with skin and respiratory irritation among surfers and an estimated mortality of up to 250,000 marine animals across 400 species.
Estuarine ecologist Faith Coleman identified Noctiluca scintillans, also known as 'sea sparkle,' as the probable species in the Tasmanian sightings, based on photographic evidence. Coleman noted that Noctiluca scintillans is not known to produce toxins but consumes small invertebrates and fish eggs.
Observations and Official Response
Marine scientist Lilly Henley, affiliated with Neighbours of Fish Farming, reported observing significant growth of the suspected bloom and suggested a potential link to the salmon farming industry, referencing similar situations in Chile. Henley also reported experiencing a tingling sensation after contact with the affected seawater. The Bob Brown Foundation documented instances of deceased octopus and sea cucumbers on affected shorelines. Bob Brown characterized the situation as an environmental emergency and called for Premier Jeremy Rockliff's direct involvement in the government's response.
Premier Jeremy Rockliff stated that no confirmed link between the observed substance and the salmon industry currently exists, emphasizing the necessity of scientific testing. Rockliff also highlighted the importance of environmentally safe and sustainable waterways for both the community and industry.