NZ Alpine Springs Under Threat From Fast-Spreading Weeds
Fast-spreading lowland weeds are invading NZ's high-country springs, but UC researchers are working to protect these once-pristine biodiversity hotspots.
Te Whare Wānanga o Waitaha | University of Canterbury (UC) Professor Angus McIntosh and Dr Helen Warburton from the University's School of Biological Sciences are supervising research into the sudden spread of aquatic weeds in the upper Waimakariri.
The study, led by master's student Saskia Brown, is examining how these typically lowland species —monkey musk and watercress —are now establishing in high-country waterways.
Recent growth observed at UC's Cass Field Station near Arthur's Pass has provided an opportunity to better understand their presence and potential impact in these alpine ecosystems.
'These aquatic weeds are well-known for overtaking lowland waterways but are now appearing at alarming rates in alpine spring systems,' Dr Warburton says.
'While the springs are biodiversity hotspots, a refuge for native species with cold, clear water and rich invertebrate life, but that's rapidly changing.'
'Some springs are still untouched, and others are already overwhelmed,' Dr Warburton says. 'We have a window of opportunity to act; either we manage this now, or we risk losing these habitats for good.'
Brown has drawn on UC student data from 2004 to track ecological changes over time.
'These invasive weeds are now widespread, even in remote areas. Our data shows that the changes are relatively recent and rapid, and they are reshaping stream life by reducing invertebrate diversity,' she says.
The research has ruled out nutrient enrichment as a driver, and the team is now exploring other possible causes, including rising temperatures, grazing by introduced animals, and human or animal-assisted seed spread.
Professor McIntosh says while the Department of Conservation has begun controlling some weed outbreaks, Brown's research is designed to drive broader regional responses and advocate for effective, practical strategies to support long-term weed removal.
'Springs that once supported distinct and diverse invertebrate communities are now becoming increasingly uniform, dominated by species like the invasive mud snail. Slowed water flow and dense weed growth are replacing the rocky streambeds that many native species rely on,' he says.
The UC research team stresses that long-term success depends on collaboration with local landowners, agencies, and communities to develop cost-effective, ecologically sound solutions that also recognise cultural values, including the role of watercress as a traditional food source.
Brown's research is supported by the University's Cass Field Station and builds on earlier undergraduate summer projects, reinforcing the long-term value of student-led science in protecting Aotearoa's unique environments.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Scoop
11 hours ago
- Scoop
NZ Alpine Springs Under Threat From Fast-Spreading Weeds
Press Release – University of Canterbury Fast-spreading lowland weeds are invading NZs high-country springs, but UC researchers are working to protect these once-pristine biodiversity hotspots. Fast-spreading lowland weeds are invading NZ's high-country springs, but UC researchers are working to protect these once-pristine biodiversity hotspots. Te Whare Wānanga o Waitaha | University of Canterbury (UC) Professor Angus McIntosh and Dr Helen Warburton from the University's School of Biological Sciences are supervising research into the sudden spread of aquatic weeds in the upper Waimakariri. The study, led by master's student Saskia Brown, is examining how these typically lowland species —monkey musk and watercress —are now establishing in high-country waterways. Recent growth observed at UC's Cass Field Station near Arthur's Pass has provided an opportunity to better understand their presence and potential impact in these alpine ecosystems. 'These aquatic weeds are well-known for overtaking lowland waterways but are now appearing at alarming rates in alpine spring systems,' Dr Warburton says. 'While the springs are biodiversity hotspots, a refuge for native species with cold, clear water and rich invertebrate life, but that's rapidly changing.' 'Some springs are still untouched, and others are already overwhelmed,' Dr Warburton says. 'We have a window of opportunity to act; either we manage this now, or we risk losing these habitats for good.' Brown has drawn on UC student data from 2004 to track ecological changes over time. 'These invasive weeds are now widespread, even in remote areas. Our data shows that the changes are relatively recent and rapid, and they are reshaping stream life by reducing invertebrate diversity,' she says. The research has ruled out nutrient enrichment as a driver, and the team is now exploring other possible causes, including rising temperatures, grazing by introduced animals, and human or animal-assisted seed spread. Professor McIntosh says while the Department of Conservation has begun controlling some weed outbreaks, Brown's research is designed to drive broader regional responses and advocate for effective, practical strategies to support long-term weed removal. 'Springs that once supported distinct and diverse invertebrate communities are now becoming increasingly uniform, dominated by species like the invasive mud snail. Slowed water flow and dense weed growth are replacing the rocky streambeds that many native species rely on,' he says. The UC research team stresses that long-term success depends on collaboration with local landowners, agencies, and communities to develop cost-effective, ecologically sound solutions that also recognise cultural values, including the role of watercress as a traditional food source. Brown's research is supported by the University's Cass Field Station and builds on earlier undergraduate summer projects, reinforcing the long-term value of student-led science in protecting Aotearoa's unique environments.
Scoop
12 hours ago
- Scoop
NZ Alpine Springs Under Threat From Fast-Spreading Weeds
Fast-spreading lowland weeds are invading NZ's high-country springs, but UC researchers are working to protect these once-pristine biodiversity hotspots. Te Whare Wānanga o Waitaha | University of Canterbury (UC) Professor Angus McIntosh and Dr Helen Warburton from the University's School of Biological Sciences are supervising research into the sudden spread of aquatic weeds in the upper Waimakariri. The study, led by master's student Saskia Brown, is examining how these typically lowland species —monkey musk and watercress —are now establishing in high-country waterways. Recent growth observed at UC's Cass Field Station near Arthur's Pass has provided an opportunity to better understand their presence and potential impact in these alpine ecosystems. 'These aquatic weeds are well-known for overtaking lowland waterways but are now appearing at alarming rates in alpine spring systems,' Dr Warburton says. 'While the springs are biodiversity hotspots, a refuge for native species with cold, clear water and rich invertebrate life, but that's rapidly changing.' 'Some springs are still untouched, and others are already overwhelmed,' Dr Warburton says. 'We have a window of opportunity to act; either we manage this now, or we risk losing these habitats for good.' Brown has drawn on UC student data from 2004 to track ecological changes over time. 'These invasive weeds are now widespread, even in remote areas. Our data shows that the changes are relatively recent and rapid, and they are reshaping stream life by reducing invertebrate diversity,' she says. The research has ruled out nutrient enrichment as a driver, and the team is now exploring other possible causes, including rising temperatures, grazing by introduced animals, and human or animal-assisted seed spread. Professor McIntosh says while the Department of Conservation has begun controlling some weed outbreaks, Brown's research is designed to drive broader regional responses and advocate for effective, practical strategies to support long-term weed removal. 'Springs that once supported distinct and diverse invertebrate communities are now becoming increasingly uniform, dominated by species like the invasive mud snail. Slowed water flow and dense weed growth are replacing the rocky streambeds that many native species rely on,' he says. The UC research team stresses that long-term success depends on collaboration with local landowners, agencies, and communities to develop cost-effective, ecologically sound solutions that also recognise cultural values, including the role of watercress as a traditional food source. Brown's research is supported by the University's Cass Field Station and builds on earlier undergraduate summer projects, reinforcing the long-term value of student-led science in protecting Aotearoa's unique environments.
1News
a day ago
- 1News
Experts take to skies to create flood maps of Auckland
Auckland Council is taking to the skies again to deploy state-of-the-art LiDAR (Light Detection and Ranging) technology to map critical waterways. It's part of the Council's Making Space for Water Programme – a response to the 2023 Anniversary Weekend floods – to ensure flooding on that scale doesn't happen again by combining infrastructure upgrades with the use of natural environments. "As we rely more and more on these natural networks to do the work of stormwater to convey flows, we need to understand how they're able to cope," said Auckland Council's principal of waterways planning Danny Klimetz. The LiDAR technology provides virtual walk-throughs of stream networks to detect changes, helping enhance flood resilience across Auckland. Auckland already utilises some regional LiDAR data, but these data sets are 20 times more accurate. ADVERTISEMENT "We knew we needed something better," said Klimetz. "Something with more density." His team connected with the University of Canterbury, which has been using state-of-the-art LiDAR tech for stream management. "We've used it from anywhere to do change detection on braided rivers in the South Island, we did a lot of the emergency surveys after Cyclone Gabrielle, trying to figure out where stop banks had failed and where stop banks were going to be needed," said Justin Stout, a geospatial research scientist at the University of Canterbury. Earlier this year, a low-flying EC120 helicopter equipped with LiDAR sensors was gathering high-resolution data across approximately 328 square kilometres of the region, covering areas from Matakana and Whangateau in the north, to urban catchments like Swanson and Meola Creek. This time the data is being collected from a 233 km2 area including all of the North Shore, parts of Henderson Creek and Whenuapai as well as areas around Pukekohe. 'This data will help us visualise and understand the intricacies of Auckland's waterways in a way that hasn't been possible before, right down to individual trees, slips, and bank conditions. It will equip us to tackle the challenges of urban flooding and climate change head-on," said Auckland Council's health waters manager Craig Mcilroy. 'It's a game-changer for managing flood risks and ensuring the city's resilience for future generations."
