NIWA and partners win new 'Outcome-Based Investment' for marine biodiversity & biosecurity
Practical plant guides for aquarium & pond owners
Saving farmed oysters from sea squirts
Insight into cold-water springs
Strategy for northern lakes
NIWA scientist Brian Sorrell surveys a fen in the upper Freshwater Valley, Stewart Island. [Photo: Alastair Suren, NIWA]
Northland has numerous lakes that lie behind sand dunes along the coast, or were dammed by past lava flows. They harbour rare and endangered native plants and fish, as well as some of the last remaining examples of native lake communities in the country.
We are helping the Northland Regional Council to identify values associated with the lakes in its region and to implement a lakes management strategy.
Sea squirts are immobile marine invertebrates. Eudistoma elongatum is a colonial species made up of hundreds of tiny individuals in bag-like bodies attached to the underside of oysters and rack-rails. They extract food from water pumped through a branchial sac in their body cavity.
An invasive sea squirt has been smothering Pacific oyster cultures in Houhora and Parengarenga Harbours in the Far North.
Mazus radicans
This native plant is good for pond edges. [Photo: John Barkla, DOC.]
Ranunculus limosella
This native plant can be used as ground cover in aquariums. [Photo: Trevor James, AgResearch.]
Aquarium hobbyists now have additional resources to guide them in selecting and culturing benign plants in the place of pest plants.
NIWA has worked with hobbyists, growers, the pet trade industry, and DOC to produce two pictorial plant guides for this purpose. One shows ten species that are at high-risk of becoming pests if introduced to New Zealand.
NIWA scientists have compiled a spatial database of New Zealand’s cold-water springs. The database contains records of nearly 2000 springs, and links each with the geology, land-use, and climate of the area.
Over 100 of the springs have biological data linked to them, and work by a postdoctoral student at NIWA suggests that the main environmental factors driving the patterns of biodiversity in cold-water springs are height above sea level, and land-use in the catchment.
Don Robertson
General Manager, Biodiversity & Biosecurity
Human impacts on the marine environment, resulting in the loss of habitat, loss of biodiversity, and risks to many species, are one of the most serious issues facing the future health of our aquatic ecosystems.
