Vol.12 No.3 - September 2004

PDF of this article (219 KB)
Malcolm Clark
Ashley Rowden
An ambitious survey looks for signs of life in the deeper waters off the Antarctic continent
Swath image of Seamount 100 off the Balleny Islands.
 
RV Tangaroa samples biodiversity in the Ross Sea. (Photo: J. Mitchell)
 
An epibenthic sled is hauled back on deck (top) and a van Veen grab is deployed over the side. (Photos: I. Everson, BAS)
 
A mixed sample of invertebrates and fish; Epimeria (A “new” species of amphipod; and a deepwater hydro coral. (Photos: M. Clark, S.

PDF of this article (211 KB)
Cathy Kilroy
Mike Scarsbrook
Graham Fenwick
“Look after the springs and you look after the river”. A bit simplistic, perhaps, but it’s a good starting point for conserving aquatic biodiversity in braided rivers.
Part of the upstream braided section of the Waimakariri River, Canterbury. (Photo: C. Kilroy)
Diagram of a braided river system showing the general habitat types sampled in this survey.
Numbers of invertebrate and algae taxa found in each habitat type sampled.

PDF of this article (112 KB)
New Zealand’s seas are rich in numbers of species of plants and animals, our fresh waters much less so. The ecosystems and the diversity in these environments are valued and vulnerable to many threats. Some of these threats are natural (floods, eruptions, undersea mudslides) and, while we need to understand their effects biodiversity, we wouldn’t try to do anything about them.

PDF of this article (313 KB)
Don Robertson
Mary de Winton
Scientific data collected on New Zealand’s feshwater fish, invertebrates, algae and aquatic plants can now be located with the click of a mouse.
NIWA has just completed an innovative web-based data-management project, funded in part by the Department of Conservation’s Terrestrial & Freshwater Biodiversity Information System (TFBIS) Programme.
Many decades of research in New Zealand have produced large amounts of environmental and biodiversity data.

PDF of this article (174 KB)
Dave Rowe
Evidence is mounting of the damage done to New Zealand freshwater habitats and native species by non-indigenous (exotic) fish.
Introduced fish such as perch, gambusia, rudd, catfish, koi carp, and tench continue to spread within New Zealand. Although some of these introductions are accidental, others are clearly deliberate, unapproved attempts to create new recreational fisheries. While these introductions may benefit some anglers, the environmental costs need to be weighed carefully.

PDF of this article (195 KB)
Graham Fenwick
Mike Scarsbrook
NIWA research has discovered a biodiversity treasure trove in New Zealand’s aquifers, often living more than 20 m beneath the soil surface.
There’s life in groundwater: highly specialised species of invertebrates have adapted to complete their entire life-histories in lightless, subterranean waters. Unusual they may seem, but only because of their unfamiliarity.
Schminkea sp., a water mite from Otago groundwaters (Photo: D.

PDF of this article (109 KB)
NIWA established the Centre in 2002 to enhance access to our scientific expertise and services, to develop new tools and techniques, and to increase awareness of aquatic biodiversity and biosecurity.
The Centre is underpinned by NIWA’s research capacity in physical and chemical oceanography, hydrology, marine geology, climate modelling, aquaculture and fisheries, as well as access to vessels and extensive marine and freshwater science research facilities.
Documenting and preserving our biodiversity
To manage our aquatic environment sustainably, we need to k

PDF of this article (153 KB)
Fleur Matheson
Tony Dugdale
Rohan Wells
Aleki Taumoepeau
Josh Smith
A simple procedure can help stop the spread of aquatic pests.
NIWA scientists working with ARC staff to sterilise and clear gill nets at Lake Wainamu. (Photos: J. Clayton)
 
Sterilising fyke nets of a commercial eel fisherman. (Photo: R. Wells)
There are numerous aquatic pests in New Zealand freshwater environments. Some of the better known species include koi carp, catfish, gambusia (mosquitofish) and the noxious weeds hornwort, egeria and lagarosiphon.

PDF of this article (98 KB)
Anne-Nina Lörz
Niel Bruce
NIWA holds a major collection of marine invertebrates from beyond the intertidal zone for the world’s fifth-largest EEZ.
The collection holds several million specimens from more than 10,000 stations.
For many marine invertebrate groups, the southwestern Pacific has the world’s highest species diversity.

PDF of this article (159 KB)
Ashley Rowden
Malcolm Clark
Years of investigations are beginning to reveal the secrets of seamount biodiversity.
Digital terrain model (3x vertical exaggeration) of the Graveyard seamount complex.
Different substrates support different fauna: rich beds of stony coral.
Rich beds of stony coral.
Low biodiversity on a volcanic slope.
Hydrothermal vents on seamounts support species including the mussel Gigantidas gladius (top) and the clam Bathyaustriella thionipta. (Photos: A. Rowden, A.

PDF of this article (206 KB)
Drew Lohrer
Nicole Hancock
Experimental work with sand and mud habitats highlights the importance of biodiversity from the bottom up.
Muddy and sandy sediments cover 70% of the world’s seafloor and are found in New Zealand harbours, estuaries and open coastal environments. Sediments have a reputation for being flat and brown, and are certainly less glamourous than the colourful rocky pinnacles, seamounts and coral reefs that get media attention.

PDF of this article (153 KB)
Aleki Taumoeeau
Rohan Wells
A new use for a common tool makes lake management easier.
Lake and waterways managers often deal with large areas of nuisance weeds that have the potential to interfere with boating, fishing and biodiversity. Control programmes are best implemented before the weeds become an acute problem.

PDF of this article (73 KB)
Dennis Gordon
How many species live in the seas around New Zealand? Thanks to Species 2000: New Zealand, we can now answer that question with some degree of precision – at least for described species and those in museum collections. Taxonomists throughout New Zealand and in many other parts of the world are sharing their data to arrive at tallies for all known species in the New Zealand biota, on land, in fresh waters, and in the sea. The total number of marine species that we know about is circa 15,450, compared to c. 4000 freshwater species and c.

PDF of this article (202 KB)
John Leathwick
Malcolm Francis
Paul Taylor
A new way of modelling trawl survey data is an important advance for mapping and protecting biodiversity.
Sorting the catch from a research trawl survey. (Photo: M. Francis)
Predicted probability of capture for snapper. (Click for detail and two other species)
 
Recorded and predicted distribution of snapper.
 
Seasonal variation in catch rate for four fish species.

PDF of this article (335 KB)
Paul Champion
Potential pests could be living in your aquarium or garden pond.
A significant threat to the biosecurity of New Zealand’s freshwater habitats comes from plants that have been intentionally introduced. Over 70 freshwater aquatic plants introduced into New Zealand have now naturalised here and many have become problem weeds, with most New Zealand lakes, rivers and streams affected by at least one of these species. Impacts are significant, including reduction in indigenous biodiversity and economic losses.

PDF of this article (215 KB)
Geoff Read
Sean Handley
An invasive worm makes for trouble, not pearls, inside a prized shellfish.
A line of healthy green-lipped mussels in culture.
A large broken blister inside an infested mussel shell and the head region of a live Polydora haswelli. (Photos: G. Read)
A feeding Polydora haswelli projects its palps and P. haswelli inside a blister; palps in this individual are regenerating. (Photos: G.