Key Takeaways
- Manta rays in New Zealand have been assigned the threatened status due to pollution and boat strikes
- The Department of Conservation has changed the status of manta rays from ‘Data Deficient’ to ‘Threatened – Nationally Vulnerable’
- Basking and Plunket’s sharks are now considered ‘Threatened – Nationally Critical’, the last status before extinction
- Pollution, habitat degradation, and vessel activity are major threats to manta rays and other shark species in New Zealand
- Further research is needed to understand population pressures and inform conservation management decisions for these species
Introduction to Manta Rays in New Zealand
Manta rays, which can grow up to nine metres wingtip-to-wingtip, are found in the Hauraki Gulf and other parts of New Zealand. However, these magnificent creatures are under threat from pollution and boat strikes. The Department of Conservation has assigned manta rays the threatened status after a new report found that their numbers were dwindling. This change in status represents a greater level of concern for the species than previously held, and it is a wake-up call for conservation efforts to protect these amazing animals.
Threats to Manta Rays
The main threats to manta rays in New Zealand are pollution, habitat degradation, and vessel activity. According to Dr Karen Middlemiss, Senior Science advisor at the Department of Conservation, manta rays spend about six months in New Zealand waters each year when it’s warm. However, during this time, they are often found injured, and pollution in the waters, disturbance in key aggregation sites, and boat strikes are major concerns. The Department of Conservation staff often find manta rays with evidence of boat strikes, which highlights the need for more careful management of vessel activity in areas where manta rays are known to aggregate.
Conservation Status of Manta Rays and Other Shark Species
The conservation status of manta rays has been changed from ‘Data Deficient’ to ‘Threatened – Nationally Vulnerable’. This change is based on a new report that assessed the conservation status of 113 species of chimaeras, sharks, and rays in New Zealand. The report found that manta rays are not the only species that are under threat. Basking and Plunket’s sharks are now considered ‘Threatened – Nationally Critical’, which is the last status before extinction. The disappearance of the basking shark from New Zealand’s shores is very concerning, and urgent research is required to better understand population pressures and inform conservation management decisions for these species.
Need for Further Research
Despite the changing conservation status of manta rays and other shark species, there is still a lot that is not known about these animals. According to Dr Middlemiss, current estimates suggest that there are just a few thousand manta rays in New Zealand, but further data is needed to confirm this. Additionally, there is a need to understand the population size, age structure, and regional connectivity of manta rays with other Pacific populations. This lack of knowledge highlights the need for more research and monitoring of manta rays and other shark species in New Zealand to inform effective conservation management decisions.
Conclusion and Call to Action
The changing conservation status of manta rays and other shark species in New Zealand is a wake-up call for conservation efforts to protect these amazing animals. Pollution, habitat degradation, and vessel activity are major threats to manta rays and other shark species, and urgent research is required to better understand population pressures and inform conservation management decisions. The Department of Conservation and other stakeholders must work together to protect these species and their habitats, and to raise awareness about the importance of conservation efforts to protect New Zealand’s marine biodiversity. By taking action to protect manta rays and other shark species, we can help to ensure the long-term health and sustainability of New Zealand’s marine ecosystems.
