Everyday Bluebottle Predators
I have always wondered what on earth eats the bluebottles that wash up onto our beaches during the summers. The bluebottles can give a very painful sting and can leave large welts on your skin. Bluebottles, or Pacific Man o’ War float on the surface of the ocean and move around with ocean currents and the wind. Bluebottles are ecologically known as plankton because they are organisms that drift on the surface of the ocean, without having any formal means of locomotion to move themselves. Bluebottles eat small planktonic organisms that come into contact with their stinging tentacles that hang into the water.
Another type of floating organism that commonly washes up on our beaches is the By-the-wind-sailor which has the special name of Velella velella. This animal is related to the bluebottles in that it also has stingers that capture small plantonic organisms, but this animal is not known to sting people.
All animals have predators, and the By-the-wind sailors and Bluebottles that wash up on most east coast Australian Beaches are no exception. Recently at MacMasters Beach two really interesting animals washed up which are the natural predators of bluebottles, both are molluscs, one a snail, the other a sea slug or nudibranch. The common purple snail, has a “bubble raft” that enables the snail to float on the surface of the ocean and it is a predator of both the bluebottle and the By-the-wind sailor’s.
The predator I find really interesting is the Blue Sea Slug, (Glaucus atlanticus), which is a predator not just of the bluebottle and the By-the-wing sailor, but also the Common Purple Snail. I collected a couple of these sea slugs, photographed and videoed them and then released them back into the water. Apparently these creatures travel upside down when floating, the stripy side is in fact the underside and the top is silver in colour. They eat the body of the bluebottles, and the stinging cells in the tentacles get stored in the slugs body and acts as a protection against predators.
A little more information:
Stop the Wildflower – Waratah Theft
Waratahs (Telopea speciossisma) are in full flower at the moment and some of the best wildflower displays you can see are within Brisbane Water National Park around the Warrah Trig area on the NSW Central Coast, just north of Sydney.
Unfortunately, Waratah blooms are being poached from the bush and Cathy Offord from the Royal Botanic gardens, Mt Annan and I conducted a study on efforts to reduce Waratah poaching by painting some of the flowers with blue paint. The study revealed that although the painting did reduce the rate of theft a little, there was not a real difference between the rate of theft between painted and unpainted flowers.
A Compost heap as big as a small car? Don’t be mistaken, this is size of the incubator for the eggs of the Australian Brush-turkey (Alectura lathami).
Brush-turkeys have been nesting in my backyard for several years now, and around the winter solstice the males begin to make their mound, or begin to remodel an existing mound in preparation to attract a female to mate with. The nests are built on the ground and are mounds built from leaves, sticks and practically anything loose on the ground including plastic bags, and rubbish. The mounds are commonly 4 meters across and 1metre high, although I have seen mounds that are nearly 2 meters high and 6 meters across. If a cubic metre of leaf mulch and stick weighs about 40kg, then a brush-turkey mound must weigh at least 640kg which is an impressive size for a birds nest!
The female brush-turkeys lay their eggs inside the mound within a hole created by the male. Once the egg is laid, the male covers the egg with leaf litter and tends the mound. Instead of sitting on the eggs ans most birds do, the male brush-turkey incubates the eggs by adding or removing vegetation from the mound. The mound is like a giant compost heap in the sense that the vegetation in the mound begins to rot through microbial decomposition and begins to generate heat through the decompositional process. The male can adjust the heat of the mound by removing vegetation, thereby cooling the mound, or by adding vegetation to the mound which increases microbial activity and hence heats the mound. I’ve noticed that brush-turkeys are continually adjusting the amount of vegetation depending on whether the mound is exposed to sunlight and or moisture from rainfall.
The male brush-turkey uses his beak to determine the temperature of the mound, he sticks his head into the mound, hence the lack of feathers on his head. He can adjust the temperature of the mound to between 33-38 degrees Celsius. The brush-turkey eggs are quite large (12% of the females body weight) have a very high yolk content (67%), which allows the chick to be very well developed when it hatches after around 50 days in the mound.
Chicks fall prey to cats, foxes, dogs, birds of prey and goannas. Goannas also dig into the mounds to eat the eggs. At around 3 weeks of age the chicks turn from brown to black and develop their adult plumages and males can begin to build mounds at 8 months of age. Chicks have to fend for themselves without any help from the parents when they dig themselves out of the mound and very quickly they can fly to avoid predators as they emerge from the mound with fully developed wing feathers.
Brush-turkeys roost at night high in trees and roost communally and I have seen up to 20 birds in a single spotted-gum tree at Hardy’s Bay. Birds can travel large distances to roost and can make their way to the tops of trees which is quite a sight for such a large bird which spends most of its time on the ground.
An unwelcome surprise in your pool – a drowned native marsupial
Ever gone outside in the morning to admire your pool and found that there is something dead floating in the water? Unfortunately, lots of native wildlife drown each year in backyard swimming pools, not because they cannot swim, it is because they cannot get out and swim until they are exhausted and then drown.
I have heard stories of adult northern-brown bandicoots, long-nosed bandicoots, snakes falling into swimming pools and koalas fall into backyard swimming pools on the NSW coast and will drown in pools if they cannot get out.
Why can’t they get out?
Well most Australian wildlife can swim very well -check out the koala video below Read more
In November, the urban areas of Australia become a blaze of colour with the yellow of Silky Oaks, purple of Jacaranda’s and the Red of Illawarra Flame Trees.
The flowering of these trees also marks the end of year exam time for schools and technical colleges and I remember when I was studying Horticulture in Sydney, I used to have lunch at the top of a hill overlooking Sydney and I remember vividly Read more
New Holland Mouse (Pseudomys novaehollandiae) vs House Mouse in an area recovering from wildfire
In June 2009 we did some small mammal trapping at Lake Munmorah State Conservation Area and we trapped within several areas of Wallum heath, a plant community dominated by Wallum Banksia (Banksia aemula).
One of the areas of the Wallum heath was burnt in a wildfire in February this year and I suspected that we would find the Read more
Helicopter safe usage in firefighting situations
Helicopters are an extremely valuable resource for firefighting within remote areas of bushland. We regularly train to use helicopters safely, for without safe use helicopters can be very unforgiving. We trained this week with “Park Air 3” one of the NSW National Parks and Wildlife Service (NPWS) Squirrel helicopters. What an excellent machine!
Training using these helicopters involves 3 main courses for the general remote NPWS firefighter; Click here to read more….
Wildlife and Fauna Assessment – Kilmore Murrindindi Fire – Victoria Fires 2009
Assessing the actions that are critical to the recovery of the animals affected by the Kilmore-Murrindindi Fire was one of the first tasks of the BAER fauna team. The fauna team comprised of Doug Beckers Biodiversity Officer NSW National Parks and Wildlife Service, Lisa Jameson – Fauna Specialist (US Fish and Wildlife Service), Peter Menkhorst – Victorian Fauna Specialist, Ken Griggs- Fauna Specialist (US Fish and Wildlife Service) and Steve Smith – local Flora and fauna expert, Department of Sustainabililty and the Environment.
Assessing the critical impacts on Fauna and Wildlife is a huge task Read more
Doug Beckers and the 2009 Victorian Bushfire Emergency BAER Team
During February-March 2009, I was privileged enough to be able to contribute to the Victorian Bushfire emergency as a member of the BEAR Team evaluating bushfire recovery and rehabilitation as part of the Emergency management Team at Alexandra in central Victoria.
What is the BAER Team?
The BAER Team is the Burned Area Emergency Response team. The team is made up of specialists from various disciplines in emergency fire management and recovery and the team is part of the Department of the Interior of the United States Government.
The 2009 BAER team was invited by the Victorian Government to assist with the evaluation of the impacts of the huge wildfires that occurred in Victoria in February and March 2009. Two BAER teams assisted in Victoria and I worked with the team on the Kilmore East-Murrindindi fires based in Alexandra.
What an incredible experience it was working at Alexandra, seeing all the fire devastation and talking with locals about their experiences in the fires. Something I will never forget and has made a lasting impression on my perception of community and fire management.
The Kilmore-Murrindindi BAER Team
Somersby Mintbush recovers from fire by producing seedlings.
I was involved with the burning of a patch of bush at Somersby on the Central Coast of New South Wales which contains some of the Endangered plant Somersby Mintbush (Prostanthera junonis).
We monitored the effect of the burn on the plants Read more