The Rainbow Bird Volume 4 Number 3 August 2015 (Issue 83) THE LIFE OF GANNETS Further to Evelyn Williams' article "Point Danger Gannets" in "During the incubation period, the birds go offshore for up to the last issue of "The Rainbow Bird" The Age newspaper on four days and then when they are rearing the chicks, they June 1 had a report on further research into the Life of are away for between 12 and 15 hours," she said. Gannets. Ms Wells will present the results of the study at the World Bridie Smith, Science Editor writes: Seabird Conference in Cape Town, South Africa, in October. Researchers have attached cameras and tracking devices to the tails of Australasian Gannets to get a bird's-eye view of how they forage for their food in Victorian waters. Results of the fieldwork, carried out during the most recent breeding season in October to February, uncovered a previously undescribed hunting strategy revealing the gannets can adapt their foraging habits to suit their environment. The findings, which also revealed difference in hunting behaviour between the sexes, are important because it shows the seabirds can change their behaviours to suit different environments. "This is significant, as it shows that these birds have a degree of plasticity and that information is important in predicting how they may respond to future changes to their environment," said Deakin University researcher Melanie Wells. She said given the waters of south-east Australia are among the fastest warming waters on the planet, predicting how species will respond was crucial to predicting how a top predator like the gannet would fare as the climate changed. When foraging, typically Australasian Gannets use visual cues, such as dolphins or other seabirds, to locate fish in the water. However while half the Australasian Gannets living on Pope's Eye, in Port Phillip Bay, did this when they went in Contents search of food in Bass Strait, the other half studied opted to forage in the bay's shallow waters, close to the shoreline. 1. The Life of Gannets Ms Wells said this latter group of gannets took advantage of 2. Outing to Hattah N.P. the sandbars and shallow water, where it was easier to see 3. Outing to Mallee Cliffs N.P the shadow of the prey on the seafloor. Curiously, the majority of these bay-feeders were male while the ocean- 4. A Miss Fisher Mystery feeders were evenly mixed. They were also feeding on one 5. Railing about the Rails large prey, such as red mullet or barracuda, rather than lots of smaller prey like anchovies and sardines. "This 6. The Wild Goose Chase specialisation of feeding in-shore is sex-specific and that 7. Interesting Sightings opens up all sorts of questions as to why that is," she said. 8. Facebook Groups As well as the 26 gannets studied at Pope's Eye, 23 gannets from Point Danger, near Portland, were studied. 9. Club Calendar The camera and GPS device attached to their middle tail feathers weighed 50 grams or about 2 per cent of a bird's body weight. "The camera faces forward so we really get a bird's-eye view," Ms Wells said. "We see what they see." BirdLife Mildura P. O. Box 1722, Mildura, VIC 3502 The Rainbow Bird Editor: Rae Jeffers, [email protected] The fieldwork started at end of October 2014, which was the start of the breeding season. The Rainbow Bird OUTING TO HATTAH N.P. - MAY 9TH, 2015 We discussed Trevor Monson's talk at the last club meeting, sugars and starches. Inside is the insect nymph, which the as we surveyed the eucalypts on the Nowingi Track at insectivorous Pardalote probably sees as a nice soft centre. Hattah. He spoke of how long each species would take to Their method of foraging is to lever insects from the leaves flower after rain, and we did notice groups of bee hives had with that specialized beak, rather than catching them in the been placed in at least 3 locations in the park, and there was air. Tim Low, in his book, "Where Song Began", contends the beginning of flowering in some eucalypts. that the pardalote has that stumpy tail adaptation to protect it from having it grabbed by large aggressive honeyeaters and other birds, who want to defend lerp and nectar patches, and have been known to kill pardalotes. The insect which is a scale species will denude and destroy eucalypts, as it has done in California. It is thought that the Pardalote in particular, protects the health of our trees. It seems that overseas birds do not feed on lerp. Perhaps also, we were seeing the result of what is called, "Winter flocking" - a survival mechanism where all the extra pairs of eyes are able to search out food which has become scarcer, and watch for predators. Bordering the track also, were the white flowers of Club Moss Daisy (above). As well, Sharon identified the rarer Autumn flowering Snowball Bush later in the day. Sadly, although the Mallee looked green and well, there was not enough recent rain to spur the Mallee Fowl on to work the 3 nest sites which Alec checked as he led us on this part of the excursion. During our travels we also came across the interesting pile pictured, that looked amazingly like animal droppings. I was intrigued to find which creature made it. The pile is called a, "push-up", and marks the burrow entrance of a sand boring beetle, a member of the scarab group. Columns of damp sand are pushed through the burrow entrance, "like toothpaste from a tube", the Australian Journal of Entomology" No.50, states. The columns dry, and fall over, and form the pile of sand castings. The beetles spend most of the time in their burrows eating the fruit of underground Mycorrhizal fungi, which they have dug to find, and spreading fungi spore. There is evidence that these fungi have benefits for the soil and for plants, one of them being they may help plants withstand drought. Australia has 166 Then, as happens in the Mallee, after travelling through known species of earth borer beetles, but little is known quiet country, we suddenly came upon a "good" bird spot. about them. In fact Simon, from the Melbourne Museum The large group of Striated Pardalote, plus some Spotted Discovery Centre, said that they didn't have enough Pardalote (a posse of Pardalote perhaps?), seemed fairly information on the distribution to know which beetle it may unconcerned as the 15 members on the outing watched be busily mining in Hattah. A study is being undertaken at these small indigenous birds. Much easier to see them on the West Australian Museum on their state's 100 or so sand this occasion - they are usually leaping about high in the boring beetles because of the perceived benefits to soil and trees, not as now, conveniently at eye level. No wonder agriculture. We did not see the beetle however. They they were there. Lerp for the taking , and no aggressive emerge only after heavy rain, and usually at dusk. Terry large honeyeaters in sight. Their scoop shaped, strong little Houston, Curator of insects at the Western Australian beaks were busy levering the cotton wool like material from Museum, advises that your best chance of seeing them is to Eucalypt leaves. The white fluff is actually the excrement of sit with a lantern in the bush just after dark, and after heavy the immature Psyllid insect, which hardens as it comes into rain. They are attracted to light. Some of our group also contact with the air, and which cocoons the insect. This saw an Owlet Nightjar near this area, so that beetle may crystallized honeydew is extremely nutritious, and contains need to be alert! 2 The Rainbow Bird The Rainbow Bird Morning smoko near the intersection of the Nowingi and About 20 young people who said that they came from a Kanardan Tracks, was looked forward to, after earlier than Steiner School, and were walking from the Hattah Store to usual breakfasts. Finley searched for Striated Grasswren the Murray River, gave us a wave as we drove past. On the here, but it was not to be. track our sightings included: Emus, a conspiracy of Australian Raven, Grey Currawong, Brown Treecreeper, a chattering of White-winged Chough, Masked Lapwing, Red- rumped Parrot, Tree Martin, Wedge-tailed Eagle. A fairly cool breeze had sprung up by lunch time, so members used their cars as wind breaks, as they shook their 'cup of soup' packets into mugs and settled into chairs. Coming out of Hattah, as we were travelling along the Iraak track we noticed that the mob of Western Grey and Red Kangaroo, some with joeys, looked in very good condition. They had obviously taken advantage of what farmers refer to as a "good green pick" as a result of Chalka Creek flooding and a myriad of young trees appearing. Peter Dunstan had suggested that we might like to come to Chris's and his place down Rudds Road in the hope of seeing the Eastern Osprey, which had caused so much interest during the Easter break. We came past a now dry Bullock Swamp to the boat ramp at the river, where they had sighted the However he was able to photograph a Long-billed Corella Osprey on more than one occasion. Not today though! We (above) later in the day. We did see a variety of birds on did see a White-bellied Sea-Eagle's nest there, as well as a our travels to Lake Mournpall, Di's list included : Grey Caspian Tern, a large group of Little Corellas, (a screech of Fantail, Pied Butcherbird, Mallee Ringneck Parrot, Grey Corellas perhaps?), and a raft of Wood Duck.