Biodiversity Conservation

By Xinran Miao u6529022

An interview with Mrs. Ziyou Yang – the Project Director at Spoon-billed Sandpiper in China©

Migratory birds utilize different regions as habitat at different stages across the breeding, passage and staging, and wintering grounds [1,2]. However, a conspicuously low percentage of migratory birds receive adequate protection across their entire habitat ranges. In the past few decades, migratory bird populations are declining rapidly around the world, which emphasizes the urgency for acting migratory birds conservation [1].

To understand better about this issue and learn to how can we contribute to migratory birds conservation, I had a conversation with Mrs. Ziyou Yang, the Project Director at a Chinese NGO (called Spoon-billed Sandpiper in China), who aims to protect migratory birds on the Yellow Sea mudflats along the East Asian-Australasian Flyway.

In this flyway, at least 33 globally threatened or Near Threatened waterbirds have occurred and 24 of them are heavily dependent on the intertidal zone, such as Spoon-billed Sandpiper (Calidris pygmaea), which was classified as Critically Endangered on the Red List of IUCN, and has been considered as one of the most threatened migratory birds in the world [4,5].

Key threats to migratory birds in the East Asian-Australasian flyway in China

“Threats faced by migratory species in the EAAF are complex, and habitat loss remains the most significant driver of decline for many waterbirds, such as the Spoon-billed Sandpiper.” —– Ziyou

“It only takes a few years’ time for a bare mudflat to become a ‘grassland’, Spartina has spread rapidly along the east coast of China over the past two decades.” —– Ziyou

Besides, invasive plant species (e.g., smooth cordgrass [Spartina spp.]) was intentionally introduced to China to accelerate the reclamation, which supports a low abundance of macroinvertebrates and insects and therefore represent poor habitat for migratory birds [2,8].

What to do for the conservation of migratory birds?

Currently, 1.39 million ha (~23.99%) of coastal wetlands in China receive protection, and policies are in place to further strengthen this protection [2]. Many scientific outreaches have been done to improve public awareness of migratory birds’ protection. A wide variety of activities such as lectures, interactive exercises, and birdwatching trips related to migratory birds conservation have been organized for people who lived nearby the south-west coast of the Yellow Sea, especially for students and local fishermen.

However, within the EAAF, international level conservation is also important to protect migratory birds since the foremost challenge in conserving migratory birds is the fact that their annual migration route spatially link sites and habitats across their life circles, and each of these areas contributes to different components of their lives [1,2].

International cooperation and coordinated actions have been implemented as well. The Bonn Convention led a multilateral platform for coordination of conservation across countries, and regional initiatives that link government and civil society organizations can be conducted to strengthen transboundary cooperation [2].

Overall, biodiversity conservation can not be achieved with efforts from a single person, region, or country, it is a global challenge that needs more close transboundary cooperation in the future. Also, as the most severe direct drivers for biodiversity loss, more efforts are encouraged to be made on avoiding habitat loss, therefore to achieve ecologically sustainable development.

Acknowledgment

Appreciation to Mrs. Ziyou Yang for providing this interview opportunity and sharing her knowledge, work experience as well as pretty photos. Thank you to Prof. Philip Gibbons for giving suggestions to write this blog.

Dorothy Mason (u6019552)

Word count: 506

Dusk is falling over the ANU. The sky is streaked with soft evening light and paddle-pop coloured clouds. It’s a Friday afternoon, and campus is bustling with students spilling out of libraries, gearing up for a night off the books and perhaps a well-earned pint.

I’ve got weekend plans of a different kind. I’ve arranged to meet up with Tay, an Honours student at the ANU Fenner School conducting research on Canberra’s most ubiquitous marsupial: the common brushtail possum (Trichosurus vulpecula).

Tay has been observing the ANU’s possum population for the past year, tracking their movements across campus in order to learn more about their denning habits and habitat preferences.

He came to the project after he became aware of how much damage possums cause to campus infrastructure. Often, they den in small cavities in ceilings or walls, damaging the building and disturbing its occupants.

“In 2018 alone, the ANU spent 1.4 million [on possum damages],” Tay tells me. “I divided that by the total number of possum issues — that’s 25 grand per possum!”

I spent several evenings walking around campus with Tay, tracking possums he had fitted with GPS collars. Once we had located a possum using the GPS signal, we made a note of the type of habitat we’d found it in: native tree, exotic tree, bare ground, road, urban building or ground cover like grass and shrubs. Tay would later go into ANU Tree Management Systems to try to find out more details about the habitat in question.

The results have been surprising.

 “We thought that the possums would have certain selection preferences for exotic trees…but they’ll take whatever when it comes to home range selection,” Tay says.

“But it could be [that] within the home range itself, they selectively feed on exotic trees. That’s what the analysis suggests when we look at habitat preferences on a tree level.”

Tay’s results are important for several reasons. Conducting good fieldwork is essential to improving monitoring practices and exercising adaptive management. Solving the ANU’s possum problem simply isn’t possible without meaningful data on how possums select their habitat.

The research also has broader implications. Understanding how native species adapt to urbanisation remains poorly studied in environmental science. And yet, more systematic research on urban ecology could dramatically improve conservation outside protected areas.

Urbanisation is progressing at a rapid rate, leading to increasingly isolated and fragmented habitat patches. This can have dire consequences for biodiversity. At the same time though, urban environments can play important roles in the protection of local biodiversity, by providing new ecological niches that native species can exploit.

Tay’s preliminary results suggests that brushtail possums in urban environments behave differently to those in the wild.

“In studies of possums in the bush, people reported possums being quite territorial, like fighting for resources and defending territory,” he says. “But within the ANU campus […] their home ranges are not exclusive. They can actually live together, mutually.”

One thing is for certain — there is still much to learn about this familiar creature.

Works cited

Carthew, Susan M., Susan M. Carthew, Beiha-Malen Yáñez, Beiha-Malen Yáñez, Laura Ruykys, and Laura Ruykys. 2015. “Straddling the Divide: Den Use by Brushtail Possums (Trichosurus Vulpecula) in Urban Parklands.” Urban Ecosystems 18 (2): 525-538.

Dixon, Kelly M., Geoffrey J. Cary, Graeme L. Worboys, Sam C. Banks, and Philip Gibbons. 2019. “Features Associated with Effective Biodiversity Monitoring and Evaluation.” Biological Conservation 238: 1-11.

Magle, Seth B., Victoria M. Hunt, Marian Vernon, and Kevin R. Crooks. 2012. “Urban Wildlife Research: Past, Present, and Future.” Biological Conservation 155: 23-32.

McKinney, Michael L. 2002. “Urbanization, Biodiversity, and Conservation: The Impacts of Urbanization on Native Species are Poorly Studied, but Educating a Highly Urbanized Human Population about these Impacts can Greatly Improve Species Conservation in all Ecosystems.” Bioscience 52 (10): 883-890.

Additional acknowledgments

All photos were kindly provided by Divyang Rathod, fellow student in ENVS3039.

All quotes are by Tay and recorded by myself on a field microphone.

U6051167 – Lara Videnovic

My volunteering project took place in Mulligans Flat Woodland Sanctuary, where I participated in the annual “Echidna Sweep” over two weekends in November.

Importance of the sanctuary

Mulligans Flat spans more than 1200 hectares of protected land in the northern outskirts of Canberra, and has been a hotspot for conservation projects since its establishment. Together with Goorooyarroo Nature Reserve, it forms the largest, most intact area of critically endangered Yellow Box-Blakely’s Red Gum Grassy Woodland in the ACT region. This woodland retains significant ecological values, supporting threatened ecosystems and providing habitat for many native species.

The sanctuary has been an important experiment in restoration and biodiversity conservation. It is enclosed by an extensive predator-proof fence, which removes the threats associated with introduced predators such as foxes and cats, and herbivores such as rabbits. The protection provided by this fence has enabled the successful reintroduction of locally extinct native species within the reserve. As a result, echidna populations in Mulligans Flat have also flourished.

Echidnas!

Foxes pose a major threat to echidnas, as they predate heavily on newborn “puggles”. The purpose of the echidna sweep at Mulligans Flat is to monitor the population size of the native short-beaked echidna (Tachyglossus aculeatus) each year, to assess the proliferation of this species in the absence of predators like foxes. Every spring, about 60 volunteers come together for two weekends to survey the entire sanctuary. They are split into zones, where they walk along transects at 10 metre intervals and scan the area, searching for the spiky creatures.

When an echidna is spotted, the Capture-Mark-Recapture method is applied to record the time and place of the sighting. The quills of each echidna are marked with a unique and colourful pattern in nail polish so that at the sweep the following week, marked echidnas can be distinguished from unmarked and the total population can be estimated.

This year, we spotted 40 echidnas – significantly less than was spotted during the sweep last year (70!). The rangers have attributed this to the exponential increase in rainfall that Canberra has experienced this spring. Much of the sanctuary has been flooded over the last few months, so echidnas are seeking shelter in burrows, bushes and thicker tussocks of grass. This makes them much harder for the average volunteer to spot, but further reiterates the importance of effective monitoring in species conservation efforts.

Reflecting on the importance of “citizen science”

Overall, my experience at Mulligans Flat was a lot of fun and emphasised just how much of a difference volunteers make towards progressing conservation initiatives. The limited funding available for conservation science means that projects like the echidna sweep simply would not go ahead if it weren’t for volunteers. Public participation in scientific research (“citizen science”) has thus become a great means for scientists to overcome data and resource limitations. Luckily, there is a great volunteer community in Canberra, with many people giving up some of their free time to get involved and decorate the local echidna populations.  

References

ACT Government, 2017. Mulligans Flat to Triple in Size, Our CBR. Available at: https://www.act.gov.au/our-canberra/latest-news/2017/august/mulligans-flat-to-triple-in-size (Accessed 5 November 2020).

Shorthouse, D.J., Iglesias, D., Jeffress, S., Lane, S., Mills, P., Woodbridge, G., McIntyre, S. and Manning, A.D., 2012. The ‘making of’ the Mulligans Flat – Goorooyarroo experimental restoration project, Ecological Management & Restoration, 13(2): 112-125.

Theobald, E.J., Ettinger, A.K., Burgess, H.K., DeBey, L.B., Schmidt, N.R., Froehlich, H.E., Wagner, C., Hille Ris Lambers, J., Tewksbury, J., Harsch, M.A. and Parrish, J.K., 2015. Global change and local solutions: Tapping the unrealised potential of citizen science for biodiversity research, Biological Conservation, 181: 236-244.

TRC Tourism, DSB, ACT Parks and Conservation Service and Woodlands and Wetlands Trust, 2016. Mulligans Flat Woodland Sanctuary Concept Plan, ACT Government. Available at: https://mulligansflat.org.au/wp-content/uploads/2016/12/D.-Draft-Mulligans-Flat-Concept-Plan-Sept-2016.pdf (Accessed 6 November 2020).

Wildlife Victoria, 2017. Short-beaked Echidna, State of Victoria Department of Environment, Land, Water and Planning. Available at: https://www.wildlife.vic.gov.au/__data/assets/pdf_file/0020/92441/Short-Beaked-Echidna.pdf (Accessed 5 November 2020).

Woodlands and Wetlands Trust, 2015. Kids on Country, ACT Government. Available at: https://mulligansflat.org.au/event/kc2/ (Accessed 5 November 2020).

 

William Jaggers (u6667998)

Word Count: 527

Imagine the scene: you drive up to an isolated, green field on the edge of Canberra. Frogs are calling in the distance, and as the sun sets, they get continually louder. As you walk towards the pond, a few sporadic calls become a chorus of Banjo frogs, plains froglets and spotted grass froglets. You pull out your clipboard and start recording the temperature, habitat structure and the species you can hear. After this, as the last licks of sunlight shine over the distant hillside, you sit quiet and make a three-minute recording, absorbing the chorus of calling as you do so.

The Beginning: A Sunset over site 1 (Source: William Jaggers)

I believe this description captures the essence of frog watching well; it’s relaxing and a great activity to do after a long day at uni or work. But frog watching isn’t just an opportunity to learn about frogs and their calls, it is an important citizen science project whereby you can contribute to a large bank of data about frog species richness and abundance.

Why Record Frog populations?

Inform Management

By recording habitat structure, weather, date, time and temperature, we are also allowing for any relationship between those variables and the abundance/richness in frog species to be taken into account. Finding these relationships can inform management. For example, we look at the width of unmown grasses that surround each pond. This can provide good data on the effects of mowing on frog populations, as the various sites have different level of impact from mowing. Say if the data displays a decrease in the frog population or a certain species due to mowing, that management can be altered to leave a wider area of unmown buffer around each pond.

Watch and find: A ‘Pobblebonk’ – Eastern Banjo Frog (Source: William Jaggers)

Examine long-term trends

During October, the frog census is completed to gauge frog populations in the ACT. Frogs are calling the most during October and especially after recent rain. However, the frog census has been changed to the whole month of October rather than one week – frogs are calling earlier, a phenomenon that is linked to climate change. Because frogwatch is a long-term survey, with data collection beginning in 2002, the long-term effects of climate change on frog populations can be assessed and the more years the survey runs for, the clearer the long-term trends will become.

Gauge Ecosystem Health

The species abundance and richness of frogs is a good indicator of ecosystem health. Simply put, if there are higher numbers and more types of frogs, the habitat for those frogs is far more complex and will therefore contain valuable habitat for other species. Certain frog species have been found to be correlated with mowing, water depth, emergent vegetation, pond type and canopy cover.

For me, any experience that enhances or fosters an appreciation of the natural environment is worthwhile; frogwatching has made me realise that there is a lot to learn about the environment surrounding Canberra, and volunteering through citizen science is a great opportunity to do it. If you would like to get involved go to https://ginninderralandcare.org.au/frogs/ and sign up.

 References:
HOEFER, A. M., and D. STARRS (2016) One pond fits all? Frogs as an indicator of urban wetland health. Final Report to Upper Murrumbidgee Waterwatch. Ginninderra Catchment Group, Canberra.

 BALDEN, L. 2020. How climate change has impacted frogs in Canberra. Canberra Times.

 HOEFER, A. M. 2015. Eavesdropping on frogs: Citizen science guiding wetland health management. Wetlands Australia. 

Keri James 3080520  

Native Forbs regenerating after fire at Scottsdale – Bulbine Lillies, Common Everlasting – October 2020 Photos David Freudenberger 

The importance of Off Reserve Conservation – What is the Bush Heritage Fund?    

Bush Heritage manages 36 reserves of 1.2 million hectares in Australia, as well as working in partnership with 14 different Aboriginal owners on another 10.1 million hectares of Country.   

Bush Heritage reserves in Australia 

As is the case for so many conservation initiatives in Australia, Bob Brown is part of this history too.  He founded the Bush Heritage fund in 1990 when he bought two blocks of Tasmanian forest adjacent to World Heritage listed forests in order to save them from woodchipping.   

Since then, he and others have bequeathed their own lands to the fund under ‘conservation covenants’, while also raising monies to purchase significant other places, such as endangered Cassowary rainforest habitat in the Wet Tropics World Heritage Area.   

What are Conservation Covenants?   

Given that so much biodiversity in the global capitalist world is now in private hands, conservation covenants are an effective way that individual land-owners can ensure that the biodiversity on their land is protected in perpetuity:   

Click to access TFN4041-ConservationCovenantBrochure_WEB.pdf

Philanthropists all around the world have been buying up biodiverse lands to save them from development.  The billionaire founders of the clothing labels ‘north face’ and ‘esprit’ purchased 810,000 hectares of biodiverse South American land to become National Park.   

Where is Scottsdale and why is it important?   

Scottsdale lies south of Canberra near Bredbo in Ngunawal Country, and was established as a bush heritage site in 2006.  It comprises 1328 hectares of the endangered ecological communities of box gum grassy woodland and temperate grassland, and is home to many rare and threatened birds, mammals, fish and reptiles:   

Animals: Rosenberg’s Monitor (vulnerable in NSW), Speckled Warbler (vulnerable in NSW), Peregrine Falcon, Brown Treecreeper (vulnerable in NSW).  Scottsdale also works with the Upper Murrumbidgee Demonstration Reach supporting the recovery of native fish in the river.   

Plants: Currawang (spearwood), Curved Rice Flower, Button Wrinklewort, Silky Swainson-pea, and the Silver-leafed Mountain Gum (only 10 populations remaining).   

Vegetation communities: Yellow-box grassy woodland (nationally critically endangered), Scribbly Gum-black Cypress-pine Forest, Tablelands Frost Hollow Grassy Woodlands, Southern Tablelands Natural Temperate Grassland (nationally endangered).   

Bush Heritage collects ‘the best and the last’ of endangered ecosystems.  Scottsdale was a controversial purchase as it had been cropped, grazed and cleared for decades.  But as grassy biomes and woodlands have been heavily cleared for agriculture globally and in this country, it is an important addition.  Less than 5% of Box Gum Grassy Woodlands survive in Australia, with some scientists like David Freudenberger predicting this percentage within Canberra to be at even less than 1%.  Globally, grasslands are the world’s least protected and most threatened ecosystems.  And they are actually as biodiverse as rainforests.   

What’s going on at Scottsdale?    

Hundreds of volunteers and organisations, including Greening Australia and Friends Of Grasslands, replant and restore yellow box woodlands.  Scottsdale has a 100 year history of cropping, clearing, erosion and drought but Bush heritage aims to restore all woodland areas as well as increase native grasses on the highly degraded valley floor by 2030.    

Some projects at Scottsdale include:  the reintroduction of the threatened striped legless lizard, the restoration of habitat in riparian and in-stream zones (carp control, willow reduction), rabbit warren mapping and closing, and an onsite nursery of local seedlings and grasses such as Bulbines, Trigger plants, Chocolate Nodding, Yam Daisies and Blue Devils – all grown from seed.   

The ANU at Scottsdale –  An Interview with David Freudenberger:   

The esteemed Dr. Freudenberger has been monitoring seedlings at Scottsdale for 10 years.  He uses Mulligans Flat as a reference condition for the ecological restoration of Scottsdale.  To recover diversity in the ground cover – which in local grasslands is usually 60 to 70 species with a handful of shrubs and only 2 or 3 Eucalypt species – Mulligans Flat has begun to restore functionality by reintroducing the small burrowing Bettong.   

This semester three Biodiversity Conservation students helped Dr. Freudenberger collect data on how the Eucalypt and Acacia seedlings that were planted by the Fenner School in 2014 fared post fire.   

The direct seeding technique successfully used at Barrer Hill, which removes the top 10cm of nutrient-enriched topsoil, had unfortunately proved less successful at Scottsdale.   

So, in 2014 the Fenner School created 100 metre transects on the valley floor and planted a variety of BGGW species into pre-cultivated (with the sides scratched up to provide purchase for the roots to take hold), and pre-watered holes, then placing corflute protection guards around each baby plant.  This requires a lot of labour and material investment.   

The following photos have been taken at the same transect site in August 2019, then March 2020, and then during this month’s monitoring:    

August 2019 – the dried grass is the invasive African Lovegrass (Egrogrostic curvula) 

March 2020 – African Lovegrass greening up… 

October 2020 – Dried seedheads of Arican Lovegrass Photos David Freudenberger  

The photos reveal the invasive, but highly functional, African lovegrass (Egrogrostic curvula), which was introduced as fodder and has dominated ground cover.  Whilst its thatch does eliminate erosion and provide a safe habitat for a high diversity of reptiles, it has been targeted for control at Scottsdale with effective herbicide – though its elimination is not possible and small patches will always remain.   

Did some seedlings survive?   

And, could those 6 year old plants who did, have survived last summer’s fires when 73% of Scottsdale burnt?   David’s initial analysis is that >90% of the seedlings may have survived!  Little research has been published on seedling survival rates (see Hnatiuk, S. et al The survival of native seedlings planted by volunteers: The Lower Cotter, ACT case study).   Even less on post-fire survival rates (see Pickup, M. et al Post-fire recovery of revegetated woodland communities in south-eastern Australia).  And this is only the second data set to record both pre and post-fire health scores of seedlings where every plant was burnt.   

Regeneration photos from Scottsdale:   

Acacia Dealabata regenerating at the root photo David Freudenberger 

Dead burnt tussock grass, other weed species filling newly vacant spaces photo David Freudenberger 

A different transect site displaying abundant native regrowth photo David Freudenberger 

Native grassland candles photo David Freudenberger 

Native paper daisies photo David Freudenberger 

Australian Bindweed photo David Freudenberger 

All biodiversity in Australia, and not just the threatened species list, is in actuality, critically endangered.  There are so few places left to grow and thrive safely amidst massive ongoing landclearing, habitat disturbance and uncaring in a climate of anthropocentrism and climate change.  Every off reserve haven is critical and Scottsdale is one such haven for the temperate grasslands ecosystem.   

More lovely photos from Scottsdale from the bush heritage website 

The Murrumbidgee River Photo Peter Saunders.   

A baby Platypus rescued from a sinkhole Photo Richard Swain. 

Photo Dave Watts. 

Rosenberg’s Goanna Photo Jeroen van Veen 

The Bare-nosed Wombat Photo Jiri Lochman  

Peregrine Falcon Photo Wayne Lawler  

 Photo Annette Ruzicka. 

Harry Logus – u6381875

I volunteered by helping an honours student, Tay Yee Seng, with his project researching brustail possums (Trichosurus vulpecula) on the ANU campus. Tay’s research involved fitting radio tracking collars to several possums, allowing them to be tracked and monitored. This can help understand possums’ behaviour and denning locations, which include buildings and infrastructureas well as trees, since possums adapt to urban environments better than many other species – because of this, possums cost the ANU over $1 million in damages each year.

Although possums are not formally classified as a an invasive species in Australia, although they are considered invasive in New Zealand where they cause similar issues to those in Australia, including competing with other species for tree hollows, damaging food crops and causing damage to buildings.

Possum Trapping

Tay is now approaching the end of his research process so I was able help him trap possums to remove their tracking collars. This is necessary for animal welfare reasons, and because the collars are expensive.

Our task was to capture four possums with collars on the ANU campus: one near the Research School of Biology (RSB), one at the Chancellery building, one near the Law building and one at the ANU Security building.

Trapping possums

On two separate nights, we set up two to three traps at each of the sites, baited with a piece of apple that we poured fish oil onto to create a strong smell to attract the possums. There are some limitations to when the traps can be set, since possums are less likely to come out in the rain, and more likely to on warmer nights.

We also radio-tracked each possum before setting traps, to ensure it was where we expected it to be. This is done using a directional antenna set to the frequency of each possum’s collar.

Once the traps were set, we returned to them after a few hours in the hope of having caught our possums with the collars. This was also a good opportunity to track the possums again, to see if they had moved. On the first night, we caught only one possum, near the Chancellery building, although it had no collar. We also saw a possum with its joey in a tree.

On the second night we caught no possums, but made some progress by seeing our collared possum in a tree near Chancellery.

We also came very close to catching the RSB possum, which we spotted in a tree. Enticing it with pieces of apple, it came within a couple of centimetres of the trap, but it didn’t seem hungry enough to venture into the trap and after an hour of waiting, it ran away.

Reflections

In undertaking this task, I came to realise how labour intensive ecologically focussed projects can be. I spent over 10 hours without making any significant progress, so I can only imagine how much time Tay must have invested over the year. Tay also spoke about the fact that if he was not doing this project, the ANU would face considerable expenses paying contractors to do the work, which highlights the extent to which budgets and financial constraints can have an impact on how effective ecological management can be.

Lauren Schenk- u6663583

Following a postponement due to rainy weather conditions, we set off for Scottsdale Reserve, Bredbo on Friday October 9^th. Our group included Dr David Freudenberger, his team and two fellow students. After a pleasant hour drive, we arrived at Scottsdale where we were greeted by a decked-out volunteer hub. We then set off into the field to start our work on measuring the regeneration of seedlings following fire. 

So, what is Scottsdale Reserve?

Scottsdale Reserve was purchased in 2006 by Bush Heritage Australia, a non-profit organisation, to prevent the subdivision of this land for housing. Covering an area of 1,328 hectares, this property had previously been used for agricultural purposes, and as such, around 300 ha had been extensively cleared. Scottsdale Reserve has a strong volunteer community who help in restoration efforts.

What’s being done at Scottsdale Reserve?

Several projects at Scottsdale have been set up to monitor the potential of recovering the endangered box-gum grassy woodlands that once dominated this region. In 2014-15 Dr Freudenberger and several of his students planted thousands of tubestock trees and shrubs native to the site. This included several eucalyptus, acacia and shrub species.

Previous years were spent observing how well the seedlings survive in regards to both: 1) the landscape and, 2) the influence of volunteers maintaining them. However, the Orroral Valley fire that swept through this part of Australia during January 2020 in what is now known as the ‘Black Summer’ presented a new question: to what extent can the seedlings survive and regenerate following fire?

Image depicting the same individual over time. From left to right, Aug 2019, March 2020, and Oct 2020 (Photos by Dr David Freudenberger)

Our Role

Armed with a trusty 100 m measuring tape and a clip board, we set out along the various transects where the seedlings had been planted. Each 100m-transect had been assigned a number which correlated to a datasheet.

On this datasheet, the specific species and its position was listed. Our role was to observe two components; the health of the individual, and the degree of regrowth/resprouting. For both health and regrowth/resprouting, this was given on a scale of 0 to 2, where 0 is dead/regrowth absent, and 2 is robust health/vigorous regrowth. Regrowth/resprouting was further classified into epicormic, lignotuber, seeding and root plates.

Top left: epicormic growth on a eucalyptus tree. Top right: lignotuber growth on Eucalyptus melliodora. Bottom left: seedling resprout of Acacia rubida. Bottom right: root plate resprouting of Acacia rubida. (Photos by Lauren Schenk 2020)

What’s the verdict?

From the general trends in the data we collected, Dr Freudenberger estimated a survival rate of over 90%! A high proportion of the Eucalyptus and Acacia seedlings were repouting/regrowing. This is incredible considering how damaged and bleak the landscape looked following the fire.

While some natives fared well against the fire others, such as the native shrub Cassinia were not so fortunate. Moving along the transect, cassinia was consistently absent. This shows the variation in survival from species to species following a natural disturbance. As our climate continues to change and frequency of fires increases, this resilience will become more and more important. Therefore, it is vital for us to understand how communities, both native and restored respond to these disturbances. The work done at Scottsdale could be crucial to enabling this understanding.

Scottsdale presents an amazing opportunity to volunteer and make a difference in a community not too far from home. I would highly recommend looking into being a volunteer here.

Word count: 500

Acknowledgements

I would like to thank Dr David Freudenberger for organising this trip and all his amazing insight into the work done at Scottsdale. I would also like to that the other members of his team, Shoshana and Peter, as well as my other fellow students for making this trip so enjoyable.

References

BUSH HERITAGE AUSTRALIA. Scottsdale [Online]. Available: https://www.bushheritage.org.au/places-we-protect/new-south-wales/scottsdale [Accessed].

DEPARTMENT OF ENVIRONMENT CLIMATE CHANGE AND WATER NSW 2011. National Recovery Plan for White Box – Yellow Box – Blakely’s Red Gum Grassy Woodland and Derived Native Grassland. Department of Environment, Climate Change and Water NSW. Available at: https://www.environment.gov.au/system/files/resources/386f395f-b2c6-4e10-8fc3-e937ad277bfe/files/white-and-yellow-box.pdf

HNATIUK, S., RAYNER, I., BROOKHOUSE, M. & FREUDENBERGER, D. 2020. Survival of native seedlings planted by volunteers: The Lower Cotter, ACT case study. Ecological Management & Restoration, 21, 151-154. Available at: https://onlinelibrary.wiley.com/doi/full/10.1111/emr.12410

MAGUIRE, O. & MULVANEY, M. 2011. BOX-GUM WOODLAND IN THE ACT. Conservation Planning and Reserach Policy Division. Available at: https://www.environment.act.gov.au/__data/assets/pdf_file/0011/576848/Box-Gum_Woodland_Technical_Report_25_Cover.pdf

PICKUP, M., WILSON, S., FREUDENBERGER, D., NICHOLLS, N., GOULD, L., HNATIUK, S. & DELANDRE, J. 2013. Post‐fire recovery of revegetated woodland communities in south‐eastern Australia. Austral Ecology, 38. Available at: https://onlinelibrary-wiley-com.virtual.anu.edu.au/doi/epdf/10.1111/j.1442-9993.2012.02404.x

By Marvin Jin (u6599031)

Behavioural Ecology

White-winged choughs (Corcorax melanorhamphus) are a communal species that congregate together to form social groups. These highly territorial birds carry out obligatory cooperative breeding where a single pair dominates the group and produce offspring, while the others serve as helpers to the brood.

Like a scene straight out of a movie, birds of different groups engage in gang fights and kidnapping, all to strengthen the stability of the social group. They do so by abducting fledgelings and destroying the eggs and nests of rival groups. These complex behaviours do not stop there as even within social groups, deception is commonplace for White-winged Choughs when resources are scarce.

Bird banding work

Studying their complex social behaviour is an ongoing endeavour for Professor Robert Heinsohn from the Fenner School. Assisting on this work is Dr Constanza Leon, who I first heard of this work from over last summer. Professor Heinsohn and his colleagues have refined techniques and methods used to study individual-based social behaviour and cognition in these birds and translate them into approaches in conservation biology.

“Each bird possess a personality unique to the individual”, echoed Dr Constanza, who spent a considerable amount of time during her PhD mapping the relationships of every bird within social groups. This perspective is often important in reintroduction and monitoring projects whereby the study of individuals tell a story about the population dynamics that could inform management strategies.

My role as a scribe was to help with luring, trapping and recording the birds’ measurements while Dr Constanza took measurements and put on identification bands on their tarsus. However, being a professional bander in Australia takes a lot of commitment and skills as required by the Australian Bird and Bat Banding Scheme (ABBBS). You can imagine the state of wonderment I was in when Dr Constanza recognised an individual just by their behaviour.

Climate change and urbanisation

After several banding trips, I sat down with Professor Heinsohn for a casual interview on his perspective on his work. Of which, he shared the consequences of urbanisation on biodiversity. Using White-winged choughs as examples, he noted that as biological invasions into urbanised areas become more prevalent, there is a trade-off between urban and non-urban populations. Urban populations tend to experience lower fledgeling survival but more stable food resources, compared to their non-urban counterparts.

Under climate change, droughts may become more widespread and chough populations may be destabilised, causing a reshuffling of social groups. Individuals may choose to reside in more urbanised settings to secure more stable resources. Perhaps we should consider giving attention somewhere closer to home and think more about ecological planning in cities. The concept of ‘habitecture’ immediately came into my mind as I wonder how cities can integrate ecological values to enhance biodiversity conservation.

Acknowledgements

Thank you Professor Robert Heinsohn and Dr Constanza Leon for providing the opportunity to learn more about this charismatic species.

(490 words)

References

Beck, N.R. and Heinsohn, R., 2006. Group composition and reproductive success of cooperatively breeding white‐winged choughs (Corcorax melanorhamphos) in urban and non‐urban habitat. Austral Ecology, 31(5), pp.588-596.

Heinsohn, R., Dunn, P., Legge, S. and Double, M., 2000. Coalitions of relatives and reproductive skew in cooperatively breeding white-winged choughs. Proceedings of the Royal Society of London. Series B: Biological Sciences, 267(1440), pp.243-249.

Dai, A., 2013. Increasing drought under global warming in observations and models. Nature climate change, 3(1), pp.52-58.

Baker, G.B., Dettmann, E.B., Scotney, B.T., Hardy, L.J. and Drynan, D.A.D., 1997. Report on the Australian bird and bat banding scheme, 1995–96. Environment Australia, Canberra.

Barrueto, C.L., 2019. Social structure, individual fitness and the effect of climate in an obligate cooperatively breeding bird, the white-winged chough (Corcorax melanorhamphos).

Boland, C.R., Heinsohn, R. and Cockburn, A., 1997. Deception by helpers in cooperatively breeding white-winged choughs and its experimental manipulation. Behavioral Ecology and Sociobiology, 41(4), pp.251-256.

Heinsohn, R.G., 1988. Inter-group ovicide and nest destruction in cooperatively breeding White-winged Choughs. Animal behaviour, 36(6), pp.1856-1858.

Heinsohn, R.G., 1991. Kidnapping and reciprocity in cooperatively breeding white-winged choughs. Animal Behaviour.

Heinsohn, R.G., 1992. Cooperative enhancement of reproductive success in white-winged choughs. Evolutionary Ecology, 6(2), pp.97-114.