Upcoming outing to Blue Tier 9th December.

Craig Searle will lead this delightful walk which follows various old roads, marked tracks and creek-sides, through mature myrtles to a 810m summit boasting 360 degrees views. There is one steepish section on the descent where boulders need to be navigated. Total distance approx 4.5km. Moderate fitness required. Meet : Poimena at 10am. More information here

November Cape Portland visit

Thanks to Claudia and Dig for a great experience at Cape Portland. Read Claudia’s report including photos on our website

Some observations from Ross Coad [president]

Native forest logging has been in the news across the nation, with Victoria set to end the practice this month and Western Australia to do so in early 2024. Meanwhile, Tasmania is increasing the native forest area available for immediate harvesting—no doubt this will be a hotly debated topic during 2024.

Exhausted and emaciated short-tailed shearwaters (mutton birds) have been washing up dead and dying on Australia’s east coast during October and November this year. This type of mass mortality event was first reported in 1851, and has been repeated at irregular intervals since then. The following article in The Conversation includes a link to a report on a mass mortality event in 2000:

https://theconversation.com/why-are-dead-and-dying-seabirds-washing-up-on-our-beaches-in-their-hundreds-217349

The Maugean skate continues to traverse thin ice. There are plans for a captive breeding program, but to what end if the skate’s future in its natural habitat cannot be secured? A sign of the future where life in an aquarium is the only option?

Our very interesting recent visit to Cape Portland in November reminded me of a report published by the Royal Society of Tasmania on the flora and fauna of the Musselroe Wind Farm, available on our website https://netasfieldnats.com.au/wp-content/uploads/2023/02/Baker-et-al-2021-Musselroe-flora-and-fauna-surveys.pdf.  This activity provided an opportunity for either a day trip or an overnight stay, according to your preference. The windfarm is an example of a rare opportunity to provide a level of protection to a significant area of land whilst simultaneously generating renewable energy.

You never know what you might find when you look under a plant pot. To my surprise, I found a female redback spider (Latrodectus hasselti) guarding several egg sacs. No spiders were harmed in this interesting event, but one was rehomed.

 All the best for Christmas and the New Year. I look forward to seeing you all when we return in 2024!

 Spot a Swiftie September to March

All BirdLife Tas members, birdwatchers and keen photographers are invited to register their observations of the Swift Parrot. All sightings logged in Birdata will help us understand more about the parrots’ broader movements, diet, behaviour, habitat and threats, and so contribute to protecting this critically endangered parrot.

Click here to learn more about identifying the bird and listen to its distinctive call in BirdLife Australia’s Swift Parrot ID guide.

In Birdata, simply select ‘General Birdata Survey’ and ‘Incidental Search’ survey type and add your observations, such as number of birds, location, nesting or foraging behaviour and more. (If you’ve sighted them during another survey type, just add the details )

New to Birdata? You can register as a new user here.
Register on your PC/Laptop first, and from there you can download the mobile app, log in and report any sightings on the go. Or simply enter your field notes into the Birdata website later.

Natural Values Atlas: NRE Tasmania is also keen to receive your sightings directly, as well as locations of flowering Tasmanian Blue Gum, Brookers or Black Gum. Simply email naturalvaluesatlas@nre.tas.gov.au or log in to the Natural Values Atlas here. You can report the same details as for Birdata, but also sightings of injured or dead birds and information related to collisions etc.

Catastrophic bird flu reaches Antarctica

Avian flu has reached the Antarctic, raising concerns for isolated populations of penguins and seals that have never been exposed to the deadly H5N1 virus before. The full impact of the virus’s arrival is not yet known, but scientists are raising concerns about possible “catastrophic breeding failure” of the region’s fragile wildlife populations.

The virus was found in populations of a scavenging bird called brown skua on Bird Island, which is part of the British overseas territory of South Georgia and the South Sandwich Islands. These migratory birds probably brought it with them from South America where bird flu is widespread and has already killed an estimated 500,000 seabirds and 20,000 sea lions in Chile and Peru alone.

The current outbreak of the highly infectious variant of H5N1 – which started in 2021 – is estimated to have killed millions of wild birds. Researchers have long been concerned about its potential impact on Antarctic wildlife, because many species are found nowhere else in the world, and are not known to have been exposed to bird flu viruses before.

Email from Debbie Searle

A recent trip to Northeast Park has revealed another fern. Pteris tremula (Tender Brake).

There is a large specimen halfway along the newer Greencorps boardwalk.

Spores are in clusters (sori) on the underneath of fronds. The sori are in lines on the margins of the frond segments (pinnae), protected by pale, membranous covers (indusia).

 

Disa bracteata
By Robin Garnett – Central North Field Naturalists.

There is a new weed that is spreading across Tasmania: the South African Weed Orchid, Disa bracteata. It is invasive and has the potential to spread into bushland so we all
need to watch out for it.  In bud, Disa bracteata looks like a fleshy asparagus plant about 30 cm tall. Buds open to form scores of tiny flowers in a dense spike, with maroon-coloured hoods and protruding yellow labellums. They are self fertilising and mature to produce millions of dust-like seeds. The leaves are hairless, with purple backs.

Disa bracteata was first recorded in Western Australia in 1944, in South Australia in 1988, in Victoria in1994, and in Tasmania in 2005. Here, in Tasmania, it is mainly found along the north coast, from Smithton to Musselroe, often on road verges and in disturbed areas.

This orchid is one of the few orchid species to have become naturalised in Australia. Once established, it can spread rapidly via its minute seeds, which remain viable for about seven years. Colonised sites can have up to 80 individuals per square metre!

Recommended control methods for small infestations are to bag and dig up the whole plant, being careful to remove the two (or more) tubers. Large infestations may need to be sprayed. Plants are susceptible to herbicides in their early leafy stage.

 

Happy Christmas everyone !

Lou Brooker.