Off the coast of Australia’s far south, long-spined sea urchins are causing trouble as they expand their territory due to warming oceans. These spiky creatures feed on kelp and invertebrates, leaving behind barren areas. While lobsters are typically seen as their main predators, a recent study revealed an unexpected twist.
Researchers set up cameras outside a lobster den and placed sea urchins as bait. To their surprise, sharks were the ones devouring the urchins, not the lobsters. This discovery suggests that sharks play a significant role in controlling sea urchin populations, which could be beneficial for the preservation of kelp forests.
The warming waters off Australia’s southeast coast have allowed sea urchins to move further south, impacting kelp forests along the way. Scientists have been looking for ways to address the overpopulation of sea urchins, with a focus on maintaining healthy predator populations.
While lobsters were believed to be the main predators of sea urchins in New South Wales, the study found that sharks, specifically crested horn sharks and Port Jackson sharks, were consuming a significant number of the urchins. This behavior was unexpected, as sharks were able to handle large urchins with ease, unlike lobsters.
The experiment also highlighted the limitations of lobsters in controlling sea urchin populations, leading researchers to consider the role of sharks as potential predators. However, it’s essential to note that sharks are not the sole predators of sea urchins, and other factors such as storm damage and freshwater influx can also impact their numbers.
While the study provided valuable insights into the predator-prey relationship between sharks and sea urchins, further research is needed to understand the full extent of shark predation on sea urchin populations. Despite the limitations of the study, the findings suggest that predators capable of handling large sea urchins may be more diverse than previously thought, offering new perspectives on ecosystem dynamics.