Antarctic krill may be one of the last substantial marine living resources that is not over-exploited. But there are plans to expand the fishery to ensure krill fisheries remain sustainable under expansion. Researchers are attempting to age Antarctic krill, Euphoausia superba, to gain a better understanding of their life span and population structures.

New tracking technologies developed by CSIRO scientists may help prevent the disappearance of grey nurse sharks from Australia's eastern coast.

Scientists from CSIRO and James Cook University has discovered that upland rainforests in north Queensland have a remarkable ability to harvest water from the skies. These forests act as an aerial sponge, directly intercepting cloud moisture in a process known as cloud-stripping.

Increased sightings of noctilucent or night-shining clouds are thought to be due to cooling temperatures in the upper 'mesopause' region of the atmosphere and increasing amounts of water vapour. Since the late 1960s, the appearance of noctilucent clouds has increased. Researchers are investigating a possible link between noctilucent clouds and climate change.

Whale faeces contains much information about the animal's diet. Using DNA technology and some clever experimental design, scientists are probing the secrets of whale and other marine predator faeces to answer the questions of who eats who and how much of a commercial species a predator might eat.

Antarctica is a rich source of actinobacteria, many of which contain compounds which are expected to provide a source of new antibiotics and other pharmaceuticals. Other Antarctic bacteria are a rich source of polyunsaturated fatty acids (PUFA), the presence of which in cell membranes is thought to assist in cold and salinity adaptation.

Australia's revegetation efforts are insufficient to sustain remnant populations of small woodland birds. A Greening Australia program that aims to return birds to the landscape recognises that, to reoccupy an area, birds need a minimum of 10 to 20 hectares of native vegetation with a dense understorey, and perhaps 100 hectares to settle and breed. Birds are useful bioindicators and they provide free pest control for woodland trees. The rebirding program is a step towards evolving Australian agriculture away from the alien system brought from the Northern Hemisphere.

A survey of bird species at 132 revegetated sites in the New South Wales southern tablelands has yielded heartening news about the success of a decade of tree-planting efforts coordinated by Greening Australia.

The CSIRO's long history of environmental research is brought to life in the book, Fields of Discovery. In this extract, author Brad Collis introduces some early heroes of environmental science.

Dryland salinity is a dramatic consequence of the rapid conversion of native bush to agricultural land in southern Australia during the last 200 years. The economic, social and environmental costs of salinised land and waterways are enormous. Scientists are investigating options for revegetation and new ways of farming the land that mimic the hydrology of pre-existing natural ecosystems. This is a daunting task and farmers will need convincing that new agricultural systems will work. Governments and landholders are also adopting engineering approaches to protect assets at immediate risk.

Termites are vital to the functioning of natural ecosystems, particularly in Australia's tropical north, where they recycle nutrients in a range of ecological niches. Scientists believe that manipulating termite density and activity may help to restore degraded areas faster, or make ecosystems more resilient to disturbance.

Termites are a source of natural compounds that might be candidate drugs for human medicine, or 'smart' pesticides for agriculture. CSIRO Entomology has extracted compounds from termites that kill a variety of microbes, but have lower toxicity to mammalian cells. The find has sparked plans to pursue commercially the discovery of pharmaceuticals from insects.

CSIRO scientists have investigated the effects of climate change on tropical forests by developing a model named FANN (Forest Artificial Neural Network). Their aim was to predict how the distribution of forest types would be affected by climate changes expected in the next 50-100 years on land between Cooktown and Townsville, Qld.

Cat owners often attempt to curb their pet's hunting activities by fitting a bell to their collar to warn prey of the cat's approach. Two Australian studies concluded that cat bells had no effect on predation rate, and suggested that cats might cleverly learn to overcome the handicap of wearing a bell.

Quokkas on Rottnest Island, WA, have been virtually free of predation for about 7,000 years. Researchers have found that despite long isolation from predators and therefore relaxed natural selection, quokka showed typical group-size effects. They foraged more and looked around less as group size increased. In a similar study of western grey kangaroos, an insular population living with limited risk of predation did not exhibit the typical group-size effects observed in mainland populations subject to predation.

For 25 years, the identity of a tiny moss sample harvested near the summit of Mount Erebus, Antarctica, has eluded scientists. The application of modern genetic technology has enabled the moss to be identified as Campylopus pyriformis.

During mass migrations across the ocean floor, Caribbean spiny lobsters form single-file queues. They also show codenning (sharing of a safe retreat) and cooperative defence. Research indicates queuing reduces fluid drag on following lobsters and contributes to defence.

The issue of horse riding in conservation areas tends to generate heated debate. A review of published evidence found that, because of their large weight and small hoof area, horses have a relatively high potential for damaging the environment.

Dolphins communicate by a variety of calls or whistles. Several scientists working with dolphins have argued that they use distinctive 'signature whistles' or names. New research has found the existence of signature whistles to be a fallacy.