Recent research unveils that southern elephant seals, once abundant in New Zealand, serve as ecological indicators for the Southern Ocean. This study demonstrates their historical prevalence, the impact of climate change, and the repercussions of human activities, culminating in their significant range reduction. The findings underscore the need for proactive measures to protect not only the seals but also the broader Southern Ocean ecosystem.
Recent research highlights the importance of southern elephant seals as indicators of ecological change in the Southern Ocean. Associate Professor Nic Rawlence, Director of the Otago Palaeogenetics Laboratory, notes that while these seals currently inhabit the sub-Antarctic islands and South America, New Zealand’s beaches once thrived with their presence. At human arrival, the coastal ecosystem was bustling with fur seals, prehistoric sea lions, and a multitude of penguins, creating a rich biodiversity that is hard to envision today.
The study was conducted by international scholars, including postgraduate students Andrew Berg from the University of Sydney and Megan Askew from Otago, and published in the journal Global Change Biology. By employing palaeogenetic techniques on ancient specimens from New Zealand, Tasmania, and Antarctica, the researchers revealed that southern elephant seals were once widespread across the Southern Ocean.
Dr. Mark de Bruyn from Griffith University indicated that climate changes and human activities significantly affected the seals’ distribution over a relatively short evolutionary timeframe. Indigenous subsistence hunting and later European industrial sealing led to a drastic reduction in their range, ultimately confining them to the deep Southern Ocean and causing their extinction in Australia and New Zealand.
Associate Professor Rawlence emphasized that understanding the seals’ responses to past environmental changes could provide essential insights into their future status and the health of the Southern Ocean ecosystem. The research cautioned that unless action is taken to counter human-induced climate change, elephant seals and the broader ecosystem face serious threats ahead.
The study titled ‘Postglacial Recolonization of the Southern Ocean by Elephant Seals Occurred From Multiple Glacial Refugia’ was featured in the journal Global Change Biology and aligns with several UN Sustainable Development Goals related to sustainability and climate action.
In conclusion, the study underscores the historical significance of southern elephant seals in New Zealand’s biodiversity. Their population decline illustrates the impact of climate change and human activity on marine ecosystems. As the research reveals critical insights into the future challenges facing these seals and their habitats, it emphasizes the urgent need for effective measures to mitigate environmental deterioration and promote sustainability in marine environments.
Original Source: news.griffith.edu.au
