Impact of Climate Change on Southern Elephant Seals in New Zealand

New research reveals that southern elephant seals, once abundant in New Zealand, now face significant threats from climate change and human activities. The study provides insights into their historical range and emphasizes the need for conservation measures. Published in *Global Change Biology*, the findings underscore the importance of understanding the ecological impacts of past events on current marine life.

Recent research indicates that southern elephant seals serve as a critical indicator for the Southern Ocean’s ecological health and its response to climate change and human activities. Associate Professor Nic Rawlence from the Otago Palaeogenetics Laboratory notes that although these seals currently inhabit only sub-Antarctic islands and South America, they once thrived on New Zealand’s beaches, which were crowded with various marine species.

During the arrival of humans in New Zealand, the beaches were filled with fur seals, prehistoric sea lions, elephant seals, and numerous penguins. Professor Rawlence emphasizes the stark contrast to modern perceptions, as many New Zealanders are unaware that these magnificent creatures were once integral to the region’s biological history.

The study, conducted by international researchers led by postgraduate students Andrew Berg from the University of Sydney and Megan Askew from Otago, has been published in Global Change Biology. The team utilized palaeogenetic techniques on specimens from New Zealand, Tasmania, and Antarctica to illustrate that southern elephant seals once populated the entire Southern Ocean.

Dr. Mark de Bruyn from Griffith University’s Australian Research Centre for Human Evolution highlighted that climate change and human activities significantly altered their distribution over a brief evolutionary period. Indigenous hunting and European sealing practices led to a further decline in their range, confining them to the deep Southern Ocean and resulting in their disappearance from Australia and New Zealand.

Understanding the historical responses of elephant seals to environmental changes can provide vital insights into potential future impacts on both the seals and the broader Southern Ocean ecosystem. Professor Rawlence warns that unless actions are taken to address human-driven climate change and threats to marine ecosystems, both the elephant seals and their environment face serious challenges ahead.

The study titled ‘Postglacial Recolonization of the Southern Ocean by Elephant Seals Occurred From Multiple Glacial Refugia’ has been published in Global Change Biology.

In summary, the historical presence of southern elephant seals in New Zealand highlights the profound changes in marine ecosystems due to climate change and human activities. The research sheds light on the need for immediate measures to combat potential adverse effects on these seals and the Southern Ocean. Without proactive intervention, both the seals and their habitats may face dire consequences in the future.

Original Source: news.griffith.edu.au