ARE WE MISSING THE BIG PICTURE? HOW TO THINK GLOBAL AND ACT LOCAL FOR PROTECTED AREAS

ARE WE MISSING THE BIG PICTURE? HOW TO THINK GLOBAL AND ACT LOCAL FOR PROTECTED AREAS

By Cristian Montalvo Mancheno, 15th March 11:00 AM

Land-use change is one of the major drivers of biodiversity loss (1). Setting aside protected areas (PAs) has been the main strategy to confront this, but despite the significant increase in PAs over the last 30 years, biodiversity continues to decline globally (2, 3). At the same time, our understanding of PA effectiveness—and the ways we assess it—has evolved. To date, most assessments have only considered impacts at the local scale, but in today’s interconnected world, we must also think about how PAs contribute to net gains or losses in global biodiversity.

The first generation of PA impact assessments simply compared the amount of forest cover, or the number and composition of species, within and outside PA boundaries (e.g., 4, 5), typically finding that biodiversity was higher inside. However, these studies’ findings were swiftly contested due to the inherent location bias of PAs towards areas of low value for agriculture and other human uses. As a result, many areas under legal protection today would have remained undisturbed even in the absence of legal protection. This means that the expansion of PAs has not necessarily led to much additional conservation in terms of representing global biodiversity, and halting land-use change (6).

Furthermore, the simple inside-outside comparisons have often failed to account for land-use dynamics. When a PA is established, it might reduce destructive human activities inside, but if these activities simply move outside, the net effect locally might be reduced or even reversed. This phenomenon is generally known as spillover, that is, the local displacement of land uses to other areas.

 

These concerns motivated the development of a second generation of studies, in which the non-random allocation of PAs and/or the local spillover effect have explicitly been accounted for (e.g., 7, 8). These studies showed that the effectiveness of PAs not only is lower than those found in inside-outside comparisons, but also varies greatly. Nevertheless, even this last generation of PA impact assessments may be insufficient, because they fail to account for long-distance interactions between land systems, referred as teleconnections (9).

 

Such teleconnections, for example, may arise when PAs restrict access to resources—limiting the quantity of supply—which shifts the market equilibrium and causes price adjustments and/or the entry of new suppliers across an entire region or the world. This is especially the case in today’s interconnected world where flows of resources, people and capital across large distances affect land-use changes at any spatial scale (1, 9). In fact, teleconnections are more common than many of us would expect.

To illustrate how teleconnections might occur, let us look at the case of the collapse of the Soviet Union in 1991. This shock-like event led to the abandonment of large areas of farmland and war, with large impacts on the environment and biodiversity of many ex-Soviet countries (e.g., 10, 11, 12). In 2016, Schierhorn and colleagues (13) went beyond local impact assessments to illustrate how Russia’s transition from a state-owned to a market-oriented economy caused a long-lasting trade with Brazil, with Brazilian farmers being able to absorb the falling output from Russia due not only to large production potential of beef in the Amazon and Cerrado regions, but also to other enabling factors, such as technological advances in beef production and changes in beef trade flows at global scale. As a result, the gains in forest carbon and biodiversity in one part of the world was in part offset by losses elsewhere.

Teleconnections also play an important role in the effectiveness of policies and interventions aimed at halting biodiversity loss. For example, Ingalls and colleagues (14) investigated the displacement of deforestation under the Reduced Emissions from Deforestation and Forest Degradation (REDD+) framework. They found that the shift from net deforestation to net reforestation in Vietnam occurred through trade of forest-risk commodities[1] with Cambodia and Laos, which was facilitated by Vietnamese companies’ large-scale land acquisitions in these two neighbouring countries. Again, teleconnections meant that one country’s gain was, to some degree, another country’s loss.

While the displacement of land uses over large distances in the Mekong region has diminished the net impact of REDD+ at regional and global scales, teleconnections can also result in net gains for conservation. For example, displacement of agricultural and wood-derived products through trade, in particular to the United States, contributed to Costa Rica’s forest transition. But as Jadin and colleagues (15) showed, such teleconnection had an overall positive impact on the global environment due to striking differences in production and management practices between these two countries and the overall higher biological diversity of Costa Rica compared to the agricultural regions of the United States.

Although challenging, net impact assessments of PAs on the environment across countries, ecoregions and biomes are urgently needed to understand the trade-offs of a future expansion of PAs. This is increasingly relevant today due to the growing interest of conservation scientists and practitioners in setting aside half of the Earth for biodiversity (16, 17). Could such vast expansion bring about perverse outcomes? A recent study showed that the trade-offs between giving back half of the Earth to nature and maintaining food security are large and strongly dependent on the strategy selected and the scales of analyses (18). Therefore, describing coupling of land systems beyond local socio-ecological contexts will be an important next step in in our efforts to effectively conserve global biodiversity within national and regional networks of PAs.

[1] Forest-risk commodities are products that commonly impact forests through their conversion to other land uses or by their degradation, such as timber, semi-processed wood products, mining and agriculture (14).

Acknowledgements:

I would like to thank Linus Blomqvist (Director of Conservation and Food & Agriculture at Breakthrough) for helping me frame and structure this post around my interests in PAs and the teleconnection concept, as well as for his comments and suggestions throughout the development of this blog-post. Also, I am grateful to Carley Fuller (Post-graduate student in the D.E.E.P. Research Group, University of Tasmania) for clarifying the different terminology used in the conservation literature about the spillover effect, and for sharing with me interesting articles around these two types of research projects.

 

All posts are personal reflections of the blog-post author and do not necessarily reflect the views of all other DEEP members.

References:

  1. Lambin EF, Meyfroidt P. Global land use change, economic globalization, and the looming land scarcity. Proceedings of the National Academy of Sciences. 108(9): p. 3465–3472.
  2. Butchart SHM, Walpole M, Collen B, van Strien A, Scharlemann JPW, Almond REA, et al. Global biodiversity: indicators of recent declines. 2010. 328(5982): p. 1164–1168.
  3. Rodrigues ASL, Brooks TM, Butchart SHM, Chanson J, Cox N, Hoffmann M, et al. Spatially explicit trends in the global conservation status of vertebrates. PLoS ONE. 9(11): p. e113934.
  4. Greve M, Chown SL, van Rensburg BJ, Dallimer M, Gaston KJ. The ecological effectiveness of protected areas: a case study for South African birds. Animal Conservation. 14(3): p. 295–305.
  5. Southworth J, Nagendra H, Carlson LA, Tucker C. Assessing the impact of Celaque National Park on forest fragmentation in western Honduras. Applied Geography. 24(4): p. 303–322.
  6. Blomqvist L, Nordhaus T, Shellenberger M. Nature unbound: Decoupling for conservation. 2015. Available from: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.723.5766&rep=rep1&type=pdf.
  7. Andam KS, Ferraro PJ, Pfaff A, Sanchez-Azofeifa GA, Robalino JA. Measuring the effectiveness of protected area networks in reducing deforestation. Proceedings of the National Academy of Sciences. 105(42): p. 16089–16094.
  8. Brandt JS, Butsic V, Schwab B, Kuemmerle T, Radeloff VC. The relative effectiveness of protected areas, a logging ban, and sacred areas for old-growth forest protection in southwest China. Biological Conservation. 181: p. 1–8.
  9. Friis C, Nielsen JØ, Otero I, Haberl H, Niewöhner J, Hostert P. From teleconnection to telecoupling: taking stock of an emerging framework in land system science. Journal of Land Use Science. 11(2): p. 131–153.
  10. Baumann M, Radeloff V, Avedian V, Kuemmerle T. Land-use change in the Caucasus during and after the Nagorno-Karabakh conflict. Regional Environmental Change. 15(8): p. 1703–1716.
  11. Hostert P, Kuemmerle T, Prishchepov A, Sieber A, Lambin EF, Radeloff VC. Rapid land use change after socio-economic disturbances: the collapse of the Soviet Union versus Chernobyl. Environmental Research Letters. 6: p. 045201.
  12. Sieber A, Kuemmerle T, Prishchepov AV, Wendland KJ, Baumann M, Radeloff VC, et al. Landsat-based mapping of post-Soviet land-use change to assess the effectiveness of the Oksky and Mordovsky protected areas in European Russia. Remote Sensing of Environment. 133: p. 38–51.
  13. Schierhorn F, Meyfroidt P, Kastner T, Kuemmerle T, Prishchepov AV, Müller D. The dynamics of beef trade between Brazil and Russia and their environmental implications. Global Food Security. 11: p. 84–92.
  14. Ingalls ML, Meyfroidt P, To PX, Kenney-Lazar M, Epprecht M. The transboundary displacement of deforestation under REDD+: problematic intersections between the trade of forest-risk commodities and land grabbing in the Mekong region. Global Environmental Change. 50: p. 255–67.
  15. Jadin I, Meyfroidt P, Lambin EF. International trade, and land use intensification and spatial reorganization explain Costa Rica’s forest transition. Environmental Research Letters. 11(3): p. 035005.
  16. Dinerstein E, Olson D, Joshi A, Vynne C, Burgess ND, Wikramanayake E, et al. An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm. 2017. 67(6): p. 534–45.
  17. Wilson EO. Half-earth: our planet’s fight for life. Liveright, NY: WW Norton & Company. 2016.
  18. Mehrabi Z, Ellis EC, Ramankutty N. The challenge of feeding the world while conserving half the planet. Nature Sustainability. 1(8): p. 409–12.

 

NO COUNTRY FOR OLD TREES: TASMANIAN ANCIENT PLANTS AND NEW FIRE REGIMES

NO COUNTRY FOR OLD TREES: TASMANIAN ANCIENT PLANTS AND NEW FIRE REGIMES

By Stefania Ondei, 8th January 1:30 pm

Bushfires have been ravaging Tasmania for more than a month. This is not an isolated event, but rather the latest episode in a series of intense fires that have threated the unique biodiversity of the island over the past years. In the summer of 2012-2013, record hot temperatures and dry conditions led to a six-month-long fire season in the south-east of Tasmania; this peaked in January 2013 with the fires on the Forestier and Tasman Peninsula, where several towns were evacuated. 100 homes were lost in the town of Dunalley.

It was unprecedented, the longest fire season ever recorded in Tasmania.

In January 2016, another streak of bushfires hit the island. While this time properties were spared, fires burned over 72,000 hectares in central-western Tasmania, 20,000 of which located in the World Heritage Area. This caused severe damage to the unique sub-alpine and alpine habitats where species such as Pencil Pines, King Billy Pines, and cushion plants are found. The iconic Pencil Pines and King Billy pines (Athrotaxis cupressoides and A. selaginoides) are slow growing trees that can live over 1,000 years, but are restricted to fire-sheltered, high rainfall locations, as they lack those traits typically associated with fire-resistance, such as resprouting ability, thick bark, and aerial or soil seedbanks [1, 2]. The peat on which these plants grow, which can take millennia to form, is also prone to fire damage when dry, releasing great amounts of carbon in the atmosphere [3].

1 pencil pines

Pencil Pines and cushion plants at the Walls of Jerusalem National Park. (Credit: Stefania Ondei)

The 2016 fires reached several of those fire-sensitive habitats in western Tasmania and on the Central Highlands, where the burnt areas might take decades or centuries to recover, if at all.

The damage caused was, once again, described as unprecedented.

2

3

Alpine vegetation at lake McKenzie (Tasmanian Central highlands) before (top) and immediately after (bottom) the 2016 fires (Credit: farsouthecology.com; Dan Broun).

This summer Tasmania is facing a new fire emergency, with hundreds of professional and volunteer firefighters constantly battling the over 50 fires that have been burning across the state, reddening the Tasmanian skies and covering half of the island in a blanket of smoke.

The unique Tasmanian fire sensitive vegetation is at risk again, particularly in the Central Highlands and in the south-west, where the largest remaining forest of King Billy pines is located. To date, the Tasmanian Fire Service estimated that nearly 200,000 hectares have burnt, and, despite the relief brought by some needed rain, the fire season might be far from being over.

The extent of these fires is unprecedented.

 

The frequency at which high-intensity fires have been recently occurring in Tasmania suggests that we will continue to use the word ‘unprecedented’ for quite some time. At the very least, bushfires of similar extent and intensity will likely become the norm rather than the exception. But what is driving this change? To start a fire, three key elements need to be present: fuel, oxygen, and an ignition source. The air provides plenty of oxygen. As for fuel, in Tasmania an increase in average temperatures, as well as natural and anthropogenic variations of the westerly winds of the Southern Annular Mode, led to drier summers [4, 5], facilitating the accumulation of high amount of flammable plant material. The ignition source is provided predominantly by lightning; rarely recorded before 2000, fires started by dry storms have become more frequent in the Tasmanian Wilderness World Heritage Area, and the area burnt by those fires has also increased [6].

How will fire-sensitive vegetation respond to these new fire regimes? A study of the King Billy pine population that was damaged by an intense fire of the Central Plateau in 1961 showed little to no regeneration of the trees in the burnt area, nor presence of new seedlings [7]. This was likely exacerbated by the post-fire establishment of alpine shrubs in the area, which provide high amounts of fuel load under dry condition, potentially increasing fire frequency and determining a further decline of King Billy pines [8]. The vegetation burnt by the 2016 fires also showed scarce signs of regeneration one year after the event. There is no reason to assume that this gloomy scenario could not happen elsewhere in Tasmania. It is likely only a matter of time, before the increasingly dry conditions and the more frequent, intense, and extensive fires will reach the many – if not all – subalpine and alpine vegetation communities, shrinking beyond recovery the fire refugia in which these iconic species are forced.

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Alpine vegetation at lake McKenzie one year after the 2016 fire (Credit: farsouthecology.com).

Only a combination of short- and long-term actions will help preventing this announced ecological tragedy. For instance, every year in Tasmania a substantial amount of prescribed burning is conducted to reduce fuel load, to limit fire spread and intensity in both inhabited and natural areas. However, it is challenging to establish where to burn and what pattern to follow. Different fire behaviour models agree that the most effective approach would likely be similar to the burning practices traditionally conducted by Aboriginal people, with a large overall burnt area made by a high number of small patches, which would create a fine-scale fuel mosaic [9, 10]. Sadly, such approach would be too expensive for the limited resources available. More financially realistic treatments were also modelled, but displayed limited effectiveness [9]. Local efforts, while useful to prevent and fundamental to stop ongoing fires, are thus unlikely to be able to completely avert the increasingly catastrophic fires driven by a climate that is changing even faster than predicted. In an ideal world, strong immediate measures would be taken at a global scale to limit climate change effects. In this world, however, this is yet to happen. In the meanwhile, we thank the rain.

 

 

References

  1. Prior, L.D., B.J. French, and D.M.J.S. Bowman, Effect of experimental fire on seedlings of Australian and Gondwanan trees species from a Tasmanian montane vegetation mosaic. Australian Journal of Botany, 2018. 66(7): p. 511-517.
  2. Worth, J.R.P., et al., Gondwanan conifer clones imperilled by bushfire. Scientific Reports, 2016. 6: p. 33930.
  3. Yu, Z., et al., Global peatland dynamics since the Last Glacial Maximum. Geophysical Research Letters, 2010. 37(13).
  4. Bureau of Meteorology. Trend in mean annual temperature – 1970-2018. 2019; Available from: http://www.bom.gov.au/climate/change/index.shtml#tabs=Tracker&tracker=trend-maps&tQ=map%3Dtmean%26area%3Dtas%26season%3D0112%26period%3D1970.
  5. Mariani, M. and M.-S. Fletcher, The Southern Annular Mode determines interannual and centennial-scale fire activity in temperate southwest Tasmania, Australia. Geophysical Research Letters, 2016. 43(4): p. 1702-1709.
  6. Styger, J., J. Marsden-Smedley, and J. Kirkpatrick, Changes in Lightning Fire Incidence in the Tasmanian Wilderness World Heritage Area, 1980–2016. Fire, 2018. 1(3).
  7. Holz, A., et al., Effects of high-severity fire drove the population collapse of the subalpine Tasmanian endemic conifer Athrotaxis cupressoides. Global Change Biology, 2015. 21(1): p. 445-458.
  8. Holz, A., et al. High severity fires, positive fire feedbacks and alternative stable states in Athrotaxis rainforest ecosystems in western Tasmania. in AGU Fall Meeting Abstracts. 2016.
  9. Furlaud, J.M., G.J. Williamson, and D.M.J.S. Bowman, Simulating the effectiveness of prescribed burning at altering wildfire behaviour in Tasmania, Australia. International Journal of Wildland Fire, 2018. 27(1): p. 15-28.
  10. King, K.J., et al., The relative importance of fine-scale fuel mosaics on reducing fire risk in south-west Tasmania, Australia. International Journal of Wildland Fire, 2008. 17(3): p. 421-430.

 

 

All posts are personal reflections of the blog-post author and do not necessarily reflect the views of all other DEEP members

HONEYEATERS: CALLS, NECTAR AND POLLINATION

HONEYEATERS: CALLS, NECTAR AND POLLINATION

By Vishesh Leon Diengdoh 14th December at 11:30AM

When I had camped nearby Port Arthur in the Tasman Peninsula, this November, I was woken up at five in the morning by eight or nine Yellow Wattlebirds who kept calling in a sequence and repeating this for at least half an hour. From within my tent, I counted eight, based on the loudness and direction of the call, the ninth call was too far to make out. The same thing happened like clockwork the next morning as well. Its call has been described as a person vomiting and I once heard someone say it sounded like a deranged chicken. Those are accurate descriptions and if you have not heard what a Yellow Wattlebird sounds like you should give it a listen. I’ve noticed that a lot of birds in Australia have a screaming like calls (they sound amazing but not at 5 in the morning) and this leads me to read a book by Tim Low called Where song began. One of the things I learned from the book was that birds scream for nectar present in the flowers. The amount of nectar available to birds in Australia is enough to make nectar feeding birds defend it with loud aggressive calls to assert possession.

YellowWattlebird

Figure: Yellow Wattlebird, Anthochaera paradoxa is Australia’s largest honeyeater and endemic to Tasmania and King Island (Image source: http://www.birdlife.org.au/bird-profile/yellow-wattlebird)

Honeyeaters are nectarivorous birds of the Meliphagidae family which are distributed from eastern Indonesia to Palau, Hawaiian Islands, New Zealand and Australia. It is one of the largest family in the region with more than 170 species, with nearly 70 species occurring in Australia. Some honeyeaters are brightly coloured with striking patterns, but most are covered in shades of green, brown or grey. A common feature is a naked area on the head and presence of conspicuous clump of feathers which are often yellow or white. Males and females are nearly identical in appearance with a few exceptions (Longmore, 1991).

Honeyeaters have brush-tip tongues with numerous bristles that are long and fine allowing them to collect nectar across large surfaces and tiny fissures on tree branches. These features of the honeyeater’s tongue are different from other nectarivorous birds such as sunbirds and hummingbirds (Paton and Collins, 1989). In addition to nectar, they also consume fruits, berries, insects, manna and lerp (Barker and Vestjens, 1990).

tonguemorphology

Figure: Gross morphology and appearance in transverse sections of the brush-tipped tongue of the Spiny-cheeked Honeyeater (Acanthagenys rufogulari) (Image source: Paton and Collins, 1989)

Honeyeaters are conspicuous, highly active and aggressive both among themselves and with other species (Longmore, 1991). Although honeyeaters exhibit aggressive behaviour, a level of coexistence can exist resulting in a community of diverse honeyeaters. According to Ford (1979), larger species can easily defend a nectar source (interference competition) while smaller species are more efficient at feeding (exploitation completion). These two types of competitions create a balance to maintain species diversity in an area where nectar abundance varies spatially and temporally.

In Australia, Honeyeaters are among the major flower feeders. The genera most frequently visited are Eucalyptus, Callistemon, Banksia, Grevillea, Adenanthos, Epacris, Astroloma, Amyema, Correa, Xanthorrhoea, Anigozanthos and Eremophila. The genus Eucalyptus, with 74 species is visited by 83 species of birds making it one of the most important genus. The plant-bird relation in Australia exhibits a generalist relationship with birds visiting a range of flowers. This is different from the specific relationship between hummingbirds and plants in tropical America. There is no definitive indication as to why numerous and dominant plant genera in Australia would be pollinated by birds. Compared to insects, birds are active throughout the year and are more reliable when the flowering seasons and climate are erratic. Birds travel further distances than insects improving chances of outcrossing in plants (Ford et al., 1979).

According to the projections by Sekercioglu et al. (2004), 6-14% of all bird’s species will be extinct by 2100 and this will result in the decline of important ecosystem processes such as seed dispersal and pollination. Nectar and fruit-eating birds are expected to have a higher than average extinction which will, in turn, affect populations and communities. This would have significant importance in Australia and other oceanic regions where pollinating birds are higher than other parts of the world.

The Australian Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and the International Union for Conservation of Nature (IUCN) red list have designated the Painted Honeyeater, Black-eared Miner and Regent Honeyeater as vulnerable, endangered and critically endangered respectively. The Helmeted Honeyeater has however been listed as critically endangered by the EPBC. The threats to these species include – agriculture & aquaculture, biological resource use, climate change, invasive non-native/alien species, disease, natural system modifications and residential & commercial development.

ReagentHoneyeater

Figure: Regent Honeyeater, Anthochaera phrygia (Image source: http://birdlife.org.au/bird-profile/regent-honeyeater)

The state of the four Honeyeaters listed above represent the current situation in Australia. If we assume the projections of Sekercioglu et al. (2004) to take place, it would have serious consequences for the ecosystem. The aim of my PhD is to assess the influence of land-use and land-cover, climate change and other factors on the distribution of different pollinating birds (i.e. honeyeaters: Black-headed Honeyeater, Eastern Spinebill, Crescent Honeyeater, Little Wattlebird, New Holland Honeyeater, Noisy Miner, Strong-billed Honeyeater, Tawny-crowned Honeyeater, Yellow-throated Honeyeater and Yellow Wattlebird) in Tasmania. I’m focusing on land-use and land-cover and climate change since they are considered as the main drivers of global change (Hansen et al., 2001); with land-use change expected to have the largest impact on terrestrial ecosystems and biodiversity in the future, followed by climate change (Sala et al., 2000).

CrescentHoneyeater

Figure: Crescent Honeyeater (Phylidonyris pyrrhopterus) at Fortescue Bay. It’s a bit blurry as I only had a macro lens with me.

 

References

Barker, R. D. & Vestjens, W. J. M. 1990. The food of Australian birds 2. Passerines, CSIRO PUBLISHING.

Ford, H. A. 1979. Interspecific competition in Australian honeyeaters—depletion of common resources. Australian Journal of Ecology, 4, 145-164. https://doi.org/10.1111/j.1442-9993.1979.tb01205.x

Ford, H. A., Paton, D. C. & Forde, N. 1979. Birds as Pollinators of Australian Plants. New Zealand Journal of Botany, 17, 509-519. https://doi.org/10.1080/0028825X.1979.10432566

Hansen, A. J., Neilson, R. P., Dale, V. H., Flather, C. H., Iverson, L. R., Currie, D. J., Shafer, S., Cook, R. & Bartlein, P. J. 2001. Global change in forests: responses of species, communities, and biomes: interactions between climate change and land use are projected to cause large shifts in biodiversity. AIBS Bulletin, 51, 765-779. https://doi.org/10.1641/0006-3568(2001)051[0765:GCIFRO]2.0.CO;2

Longmore, W. 1991. Honeyeaters & their allies of Australia, Collins/Angus & Robertson.

Paton, D. & Collins, B. 1989. Bills and tongues of nectar‐feeding birds: A review of morphology, function and performance, with intercontinental comparisons. Australian Journal of Ecology, 14, 473-506. https://doi.org/10.1111/j.1442-9993.1989.tb01457.x

Sala, O. E., Chapin, F. S., Armesto, J. J., Berlow, E., Bloomfield, J., Dirzo, R., Huber-Sanwald, E., Huenneke, L. F., Jackson, R. B. & Kinzig, A. 2000. Global biodiversity scenarios for the year 2100. Science, 287, 1770-1774. https://doi.org/10.1126/science.287.5459.1770

Sekercioglu, C. H., Daily, G. C. & Ehrlich, P. R. 2004. Ecosystem consequences of bird declines. Proceedings of the National Academy of Sciences, 101, 18042-7. https://doi.org/10.1073/pnas.0408049101

 

All posts are personal reflections of the blog-post author and do not necessarily reflect the views of all other DEEP members

WOULD MOVING A ROSE BY ANY OTHER NAME SMELL AS SWEET?

WOULD MOVING A ROSE BY ANY OTHER NAME SMELL AS SWEET?

By Shane Morris, 20th November at 4:30 PM

As I watched “Arrival”, a movie about aliens descending to Earth and their interaction with a human linguist, I got thinking about the science behind the movie. This wasn’t the physics of space travel or the anatomy of the visitors but the Sapir-Whorf hypothesis*, the principle that language shapes a speaker’s world view or cognition. It is generally divided into two hypothesises; 1) the strong, language determines how we perceive the world, and 2) the weak, that language influences thought and decisions. “Arrival” deals with the strong hypothesis, and in this article I will deal with the weak, connecting these thoughts to my research on conservation translocations and proposing a new name for a scientific technique.

Arrival-poster-9

There are some fascinating examples of the interplay between language and cognition. The Kuuk Thaayore of Cape York, North Australia, have amazing navigational abilities, which is enabled by their language using only absolute directions (North, South, East, West and everything in between) rather than also using relative directions (like right, left in English)1. So, if a Kuuk Thaayore asked you to set the table you could be told to but the fork on the North North-West side and the knife on the South South-East side of the plate! An English speaker may take a few seconds to orientate themselves, while in contrast the Kuuy Thayore have spent their lives expressing themselves with absolute directions. This is quite an extreme example, but language can also influence how we categorise things due to the relationships it creates in our minds1. Many Indo-European languages have arbitrarily assigned gender to common and abstract nouns, for instance in Spanish the word “key” is feminine while in German it is masculine. It has been shown to influence the speakers of these languages perception for when asked to describe a “key”. Spanish speakers will use words like “intricate”, “lovely”, “little” and “shiny”, while German speakers use “hard”, “heavy”, “serrated” and ”useful”.  And before you think that’s because Spanish speakers are passionate and Germans are practical, or some other stereotype, this trend is consistent when a word in each language is chosen with the gender reversed1.

https://www.abc.net.au/radionational/image/4328642-3x2-580x387.jpg

Kuuy Thayore and Lera Boroditsky

These examples are about the fundamentals of the language and we are therefore stuck with them, but the Sapir-Whorf hypothesis is of great importance when we need new terms for new ideas. In his book “The Invention of Science”, the historian of science, Daniel Wooton writes “a revolution in ideas requires a revolution in language”. Wooton argues, that Christopher Columbus never said he discovered America (he used invenio meaning find out) because the word, in fact the very concept of discovery did not exist at that point.  Before the Age of Exploration, Western culture gazed backwards convinced that all worthwhile information had already been discovered in ancient Athens or Rome. Columbus and his crew had experienced something entirely unknown to the Western civilisations of yore. This then shifted the focus of Western culture to one which, to paraphrase Wooton, recognised experience as the path to discovery, and promptly ushered in the Scientific Revolution2.

https://pictures.abebooks.com/isbn/9781846142109-us-300.jpg

At this point you may be asking what a movie about aliens; cardinal direction use by Aboriginal Australians and Christopher Columbus have to do with conservation translocations? You may even be wondering what a conservation translocation is.  A conservation translocation is the movement of a species from one place to another to confer a conservation benefit3. In recent decades, these have become an increasing popular tool in conservation biology but are very controversial amongst scientists in this field.  4,5. The most contentious type of conservation translocation is the movement of a species to an area in which there is no evidence that it had previously inhabited. The main concern, an extremely valid concern, is that these have the potential to cause disastrous, unforeseen circumstances. This debate is beyond the scope of this article but one that isn’t is what this technique should be called, this may seem frivolous on the surface, yet it could have larger implications for its perception by the public. I considered this while watching “Arrival”, how the term we use for this last type of translocation may shape its future. Before you scoff at the seemingly superficial importance of a name, consider that a recent study carried out by researchers at Johns Hopkins Bloomberg School of Public Health found that the language used was key to a treatment garnering higher public support. In this study, 29 percent of people were in favour of “safe consumption sites” yet this rose to 45 percent when “overdose prevention sites” was used6.

The names currently being used for the controversial translocation technique are assisted colonisation, assisted migration, benign introduction and managed relocation. Connie Barlow argues that assisted colonisation should not be used due to its “hegemonic overtones” and its association with invasive species8. Societies that have experienced the suffering caused by colonialism are likely to oppose ideas outright due to associations with past traumas. Malcom Hunter rightly argues against assisted migration as migration is already defined within ecology to mean a round trip, which this would not be7. I oppose the term benign introduction as it is inherently misleading, making the act seem non-interventionist when the antithesis is true. Managed relocation may be the best of a bad bunch but seem more applicable to moving office, than an endangered species! It suffers from the same problems as “safe consumption sites”, it is frigid and vague.

On the advice of Maya Angelou “What you’re supposed to do when you don’t like a thing is change it. If you can’t change it, change the way you think about it. Don’t complain.” I won’t complain but try and change the thing I don’t like. My proposed name is assisted transmigration. The definition of transmigration is “to move from one place, state, or stage to another”. This captures the essence of what is trying to be achieved, we are not only moving a species from one place to another but from one state (endangered) to another (non-endangered). But perhaps you don’t agree with this term. What would you call it? For what it is called may turn out to be important.

 

*An interesting aside is that the Sapir-Whorf hypothesis is itself shaping how the idea is/was perceived. Edward Sapir ad Benjamin Lee Whorf were famous linguists at the turn of the last century who wrote about the effect they perceived language to have on cognition however they never co-authored any works together and never formulated a hypothesis! So, the name of the idea that is about language shaping thought has been named to heighten the prestige of the idea!

 

References

  1. Boroditsky, L 2009, How does our language shape the way we think? Edge, accessed 7 November 2018, < https://www.edge.org/conversation/lera_boroditsky-how-does-our-language-shape-the-way-we-think >.
  2. Wootton, D., 2015. The invention of science: a new history of the scientific revolution. Penguin UK.
  3. IUCN, S., 2013. Guidelines for reintroductions and other conservation translocations. Gland Switz Camb UK IUCNSSC Re-Introd Spec Group.
  4. Hoegh-Guldberg, O., Hughes, L., McIntyre, S., Lindenmayer, D.B., Parmesan, C., Possingham, H.P. and Thomas, C.D., 2008. Assisted colonization and rapid climate change. Science 321 (5887), pp 345-346.
  5. Ricciardi, A. and Simberloff, D., 2009. Assisted colonization is not a viable conservation strategy. Trends in ecology & evolution, 24(5), pp.248-253.
  6. Barry, C.L., Sherman, S.G. and McGinty, E.E., 2018.  Language Matters in Combatting the Opioid Epidemic: Safe Consumption Sites Versus Overdose Prevention Sites. American Journal of Public Health; 108 (9): pp 1157
  7. Barlow, C 2009. Pro “Assisted Migration” as the term of reference. Torreya Guardians, accessed 7 November 2018, <http://www.torreyaguardians.org/assistedmigrationdebate.html&gt;
  8. Hunter Jr, M.L., 2007. Climate change and moving species: furthering the debate on assisted colonization. Conservation Biology, 21(5), pp.1356-1358.

All posts are personal reflections of the blog-post author and do not necessarily reflect the views of all other DEEP members

ENERGY FOR THOUGHT

ENERGY FOR THOUGHT: FOOD SECURITY CAN BE OBTAINED THROUGH AN INCREASE IN ENERGY SUPPLY

by Elise Ringwaldt, 6th November at 2:44 PM

In 2017, I was invited to visit The Breakthrough Institute and attend their Dialogue: Democracy in the Anthropocene. Discussions at this event incorporated how human population is the driving ecological force on the planet, and decisions made about agriculture, energy and resources will influence the future planet. In reflection, I describe in this article how there are concerns for the growing human population food requirements, especially for developing nations. One way we can improve the food wasted right now, is through growth in the energy sector, which can improve technology throughout the food supply chain – saving food and corresponding resources.


Human population is estimated to reach 9 billion by 2050, and with it, rising demand for food and energy. To feed our expanding population it is estimated we would need to increase the production of food by ~70 percent! However, few people realize that we could feed billions of undernourished people right now just by reducing the amount of food wasted or lost after harvesting. In the United States alone, 31-40% of the food produced for human consumption is wasted, which is enough to feed 1 billion people. So, there is an obvious paradox here – we need more food, yet we waste enough to feed the undernourished? Where does the problem lie, and what can we do about it?

Food is lost and wasted along the food supply chain; starting from where the food is produced (e.g., farms), packaged, transported and then consumed (purchased and eaten by us). Where it is lost along this chain differs for developed and developing countries, mainly due to differences in access to technology and energy. In developed countries, modern technology and infrastructure help to reduce the amount of food wasted post-harvest along the food supply chain (Loss in developed countries can be as low 1-2% for some commodities, compared to developing countries with an average of 40%). Most developed countries depend on easily accessible energy (e.g., grid-supplied power) to run large scale operations with specialized machinery, high-tech post-harvest treatment, and secure storage facilities to reduce spoilage during post-harvest and transport.  On the other hand, developing nations typically have insufficient electricity supply and inadequate technology and/or storage mechanisms, and because of this they have greater food loss and waste post-harvest. In developing nations, one of the most successful ways to achieve food security and reduce food loss is through an increase in reliable energy. But through what mechanisms?

Energy sources, including fossil fuels, nuclear power, hydro-electricity, and renewable energy (solar and wind) are the basis for modern human activities; in the past increases in energy supply have improved standard of living, economy, and growth. Electricity supply in developing nations is scarce, with only about 40% of the population having access to energy, while in industrialized countries it is closer to 100%. Electricity is especially limited in sub-Saharan Africa where only 24% of the population have access to electricity. Furthermore, in 2013 the entire sub-Saharan Africa (excluding South Africa), which is made up of 46 countries and a population of more than 900 million, was only supported by 28 Gigawatts; this is the same electricity supply as the one country Argentina, which supports 43 million people and is a little over one-tenth of the land size of sub-Saharan Africa. In summary, many developing nations are currently relying on primitive technology and energy supplies (such as basic traditional fuels of firewood and dung cakes) to support their growing nations demand for food. Adequate power supplies will be pivotal for developing nations.

Increasing access to energy in developing nations is, however no easy feat. Lately, there have been attempts to help rural farmers reduce waste and increase the lifetime of foods by using advanced power systems, such as solar energy and biogas. However, while these technological developments are improving food security, they are only effective at small scale, and so longer term solutions are required. Grid-supplied energy is the perfect example of a stable, more wide-reaching alternative for developing nations. Grid-supplied power would provide energy for technology, to build infrastructure such as grain facilities and roads for transportation of foods, provide energy to use modern machinery during harvesting and packaging of foods, and air conditioners to power cool stores. Adequate cooling and storing of food post-harvest has the potential to reduce global food loss by at least 25%. For example, better grain storage facilities in Africa could reduce the amount of annual grain loss, potentially to feed the requirements of 48 million people a year. Additionally, 96% of India’s fresh produce is not refrigerated during storage and transport resulting in losses of over US$5 billion a year. In short, increases in energy supply has enormous potential to influence food security in developing nations.

Modern energy facilities are key to reducing food loss and waste in developing nations; and some organisations are already recognizing this need and are making a difference. Currently, there are 126 independent power projects within 18 sub-Saharan Africa countries, specifically to increase people’s access to electricity; totaling a possible 13 percent of the total power generated and 25 percent if South Africa was excluded. Policies to address future food demand are increasingly in the spotlight, with a focus on holistic investment in technology, infrastructure, and electricity. For example, the 2030 Agenda for Sustainable Development (ADS) and of the Addis Ababa Action Agenda emphasizes food security, nutrition, and sustainable agriculture among their goals, with focus on infrastructure, industrialization and innovation, impacting the 65 percent of the world’s poor whose livelihood is farming. Investment into increasing a developing country’s energy supply has clear benefits, not just through reducing food loss and waste, but also by strengthening economic opportunities.

In summary, energy increases in developing nations will feed some of the poorest due to development in infrastructure and technology which saves food along the production line. Even though developed countries may have sufficiently minimalized food loss post-harvest, consumer standards (such as the aesthetics of food produced) and the overwhelming supply of foods in supermarkets creates a paradox of food waste. Consumer, production, and the oversupply of food in developed countries means that just as much (40%) of food is wasted as developing countries. There needs to be a balance, where policies are in place so that developing nations don’t start to waste food pre-harvest at the consumer level and learn from the industrialized world mistakes to feed people adequately but sustainably.

(All posts are personal reflections of the blog-post author and do not necessarily reflect the views of all other DEEP members).

WHAT OPTIONS DO WE HAVE TO MITIGATE ‘DANGEROUS’ IMPACTS OF CLIMATE CHANGE?

WHAT OPTIONS DO WE HAVE TO MITIGATE ‘DANGEROUS’ IMPACTS OF CLIMATE CHANGE?

by Sanghyun Hong, 5th October at 11:00 AM

We, human, have known the anthropogenic climate change since 1896, or at least more than 70 years now. The Intergovernmental Panel on Climate Change was formed in 1988, and the first assessment report was published in 1990 followed by the series of meetings and agreements including the Kyoto protocol, and the Paris agreements. After the series of the meetings which wasted a valuable time to respond, we came up with an agreement that the global mean temperature increases need to be limited to or below 2 °C within this century, or 1.5 °C, if possible [1].

Although it is a little bit late, we are doing something to reduce greenhouse-gas emissions, aren’t we? We are installing on-shore and off-shore wind farms, large-scale and rooftop solar photovoltaics (i.e., solar panels), solar thermal power plants, and even expensive batteries. For example, Germany spent $222 billion on renewable energy subsidies between 2000 and 2016 [2-4]. Germany increased solar photovoltaic capacities by 40.6 GWe, wind capacities by 43.5 GWe and biomass capacities by 7.3 GWe. As a result, the greenhouse-gas emissions from electricity generation increased by 12 Mt CO2-eq during the period. Eventually, Germany will miss its greenhouse-gas emission reductions target by 2022 by a large margin [5].

Energy

Wait, something is not correct. Why do we emit more greenhouse-gas emissions when we build more renewables? The answer is simple. When you have an apple and an orange, if you replace an orange with another orange, you still have an apple and an orange. Germany replaced a large-scale zero-emission source (i.e., nuclear power) with small-scale zero- or low-emission sources (i.e., wind, solar, bioenergy). But if we keep replacing it, at some point, renewable sources will replace coal and gas too? And we still have time to reduce greenhouse-gas emissions by increasing the share of renewables right? This is an argument of some, if not all, anti-nuclear and renewable advocates. Can renewables replace nuclear and fossil fuels before it is too late?

A short answer is ‘NO’, and the long answer is ‘NEVER’. Globally, 25,081 TWh of electricity is being consumed in 2016. 16,320 TWh is from fossil fuels (e.g., coal, oil, gas), 4,170 TWh from hydroelectric power and 2,606 TWh from nuclear power. All other non-hydroelectric renewables provide < 1,990 TWh. Since 2000, the total production increased by 9,559 TWh which were mostly provided by the increases in the fossil fuel generations (additional 6,362 TWh). Nuclear power has not been changed significantly (2,590 TWh in 2000). If this trend maintains, it is highly likely that fossil fuels will be major sources of electricity in the foreseen future. Moreover, electricity is just a small part of the problem. We easily forget that electricity is only a quarter of the total final energy demand. The other three quarters are heat demand, oil consumption for transportation, direct use of fossil fuels for industry including agriculture and manufacturing. We don’t have a clear plan about how to decarbonise the other three quarters. Oh, my bad. We almost forgot to add the potential energy demand growth of developing countries yet. The economic growth of developing countries can increase the global energy demand by more than three folds [6].

The important question is do we have a chance to meet the global mean temperature target? If we are to meet the 2 °C target, what we need to do? Is the 1.5 °C target even worth to mention? According to a study recently published by Raftery, et al. [7], the global temperature increases are likely between 2.0 and 4.9 °C (median: 3.2 °C). We have a very small chance (5%) that the global mean temperature increases will be limited below 2 °C, and the lower target (1.5 °C) is not a practically possible option. Another study confirms that we must accept the difficult reality that we will never be able to reduce our greenhouse-gas emissions within the given timeframe [8]. Even if we include non-renewable options such as nuclear power and carbon capture and sequestration, it is very difficult to decarbonise the entire energy production (not just electricity, but the whole energy use) in a decade or two.

CarbonCrunch

Until recently, reducing greenhouse-gas emissions from human activities, in particular energy activities, have been the focus of climate change mitigation studies. We now have to accept that two other technological options including negative emissions (i.e., direct air capture) [9,10], and geoengineering [11,12] should be on our discussion table. Negative emission technologies are becoming cheaper but still quite expensive and inefficient in capturing CO2 from the air [11,12]. Geoengineering has regulatory barriers and can cause international conflicts over the control of the Geosystems, and its adverse impacts are largely uncertain yet [11,13].

We are living in the world full of uncertainty. We don’t know what combination is the economically feasible, and socially and environmentally acceptable. We don’t know the exact consequences of climate change. Only one thing is certain: climate will change, and we will suffer from what we have done to it. It is quite clear that our ‘Plan A: Reducing greenhouse-gas emissions’ has been failed and it will not achieve what it supposed. Although we don’t have a planet B, fortunately we do have a ‘Plan B: Preparing the high carbon future’. It is time to put the ‘Plan B’ on the table.

(All posts are personal reflections of the blog-post author and do not necessarily reflect the views of all other DEEP members).

  1. Spencer, T.; Colombier, M.; Sartor, O.; Garg, A.; Tiwari, V.; Burton, J.; Caetano, T.; Green, F.; Teng, F.; Wiseman, J. The 1.5°C target and coal sector transition: at the limits of societal feasibility. Climate Policy 2018, 18, 335-351.
  2. Reed, S. Germany’s shift to green power stalls, despite huge investments. https://www.nytimes.com/2017/10/07/business/energy-environment/german-renewable-energy.html (9 October 2017).
  3. Unnerstall, T. How expensive is an energy transition? A lesson from the German “Energiewende”. Energ Sustain Soc 2017, 7, 38.
  4. Kreuz, S.; Müsgens, F. The German Energiewende and its roll-out of renewable energies: An economic perspective. Front. Energy 2017, 11, 126-134.
  5. Amelang, S. Germany to miss climate targets ‘disastrously’: leaked government paper http://www.climatechangenews.com/2017/10/11/germany-miss-climate-targets-disastrously-leaked-government-paper/ (12 October 2017).
  6. Clarke, L.; Edmonds, J.; Kim, S.; Lurz, J.; Pitcher, H.; Smith, S.; Wise, M. Documentation for the MiniCAM CCSP Scenarios. Battelle Pacific Northwest Division Technical Report, PNNL-16735 2007.
  7. Raftery, A.E.; Zimmer, A.; Frierson, D.M.W.; Startz, R.; Liu, P. Less than 2 °C warming by 2100 unlikely. Nature Climate Change 2017, 7, 637-641.
  8. Figueres, C.; Schellnhuber, H.J.; Whiteman, G.; Rockström, J.; Hobley, A.; Rahmstorf, S. Three years to safeguard our climate. Nature News 2017, 546, 593.
  9. Williamson, P. Emissions reduction: Scrutinize CO2 removal methods. Nature News 2016, 530, 153.
  10. Tollefson, J. Sucking carbon dioxide from air is cheaper than scientists thought. Nature 2018.
  11. Zhang, Z.; Moore, J.C.; Huisingh, D.; Zhao, Y. Review of geoengineering approaches to mitigating climate change. Journal of Cleaner Production 2015, 103, 898-907.
  12. Wigley, T.M.L. A Combined Mitigation/Geoengineering Approach to Climate Stabilization. Science 2006, 314, 452-454.
  13. Corry, O. The international politics of geoengineering: The feasibility of Plan B for tackling climate change. Security Dialogue 2017, 48, 297-315.

 

 

THE FORGOTTEN TASMANIAN EMUS 

THE FORGOTTEN TASMANIAN EMUS 

by Tristan Derham, 10th September at 10:27 AM

If you are from Tasmania you have likely heard your mate’s story about the time they, or their friend’s friend, saw a thylacine. Hiking alone, they saw a big dog on the track – but wait! Those stripes! That tail! And just as they reached for their camera… the animal had slipped away into the deep bush. Clearly the thylacine lives on in the public imagination so strongly that we see it in our waking dreams.

How sad, then, that we do not hear stories of wild emus in the Tasmanian bush. No hikers come around a corner to be faced with an emu and his striped chicks stopping for a drink in a stream. No Tasmanian driver ever saw an emu dash across a gravel road and away into the night. For more than one hundred and fifty years, no Tasmanian farmer has seen the tracks of an emu in the mud by the bush block. The only emus we have now are in wildlife parks and farms. Most Tasmanians that I have spoken to don’t remember that wild emus were ever here at all.

We don’t know much about the Tasmanian emus. We don’t know how big they were, how they behaved, what they ate, whether they were abundant or which habitats they preferred. We don’t know what ecological functions were lost with the emus. For example, emus on the mainland might play an important role as long distance seed dispersers. Disturbingly, we don’t know why they disappeared so quickly.

TasEmu: Artwork by J. G. Keulemans from The Birds of Australia by G. Mathews (1910)

Artwork depicting the Tasmanian Emu – by J. G. Keulemans from The Birds of Australia by G. Mathews (1910)

Europeans began colonising Van Diemens Land in 1803. Thirty years later the emu was almost gone. It may have been extirpated even before Van Diemen’s Land was renamed in 1854. Certainly it was gone by 1870. Compared to the thylacine, which hung on for almost one hundred and fifty years, and the forester kangaroo, which lives on today in a few remnant patches, the emu disappeared very quickly indeed.

Here’s what we do know. The Tasmanian emus were closely related to Australian mainland emus, as well as the King Island and the Kangaroo Island emu populations, both of which were extirpated in the nineteenth century. Recent genetic work shows that they can all be considered members of the same species. This is not surprising given that Tasmania has only been separated from the mainland for about 14000 years.

While we don’t yet know what specific habitats that Tasmanian emus required, my recent (unpublished) research shows that they were widespread. When Europeans arrived, emus could be found from the Derwent River in the south to the Tamar in the north and from the north-east to the mid-north coast.

As on the mainland of Australia, emus and their eggs were eaten by Aboriginal people. They were important to at least some Aboriginal Tasmanians, as evidenced by eggshell remains in ancient cave sites, depictions of emus in art and the celebration of an emu dance. As James Boyce has pointed out, along with kangaroos, wallabies and pademelons, emus were an important food source for early European colonists. That is a very short list of facts for such an iconic species.

Emu in Lone Pine Koala Sanctuary Brisbane

Emu in Lone Pine Koala Sanctuary Brisbane. https://commons.wikimedia.org/wiki/Dromaius_novaehollandiae

For other facts, we have less to go on. Accounts of the size of Tasmanian emus from early settlers are conflicting – some claimed that they were smaller than mainland emus, others claim to have caught large birds on a regular basis. For example, the surveyor George Harris, who recommended the site of Hobart Town, regularly caught emus of 35 to 40 kg. These values are within the normal range of body mass for adult emus on the mainland. Little information has been gleaned from museum specimens, since there are so few. Vicky Thomson and others have hypothesised that the Tasmanian emus were slightly smaller, based on a relationship with island size and measurements from two leg bones. A recent consolidation of Tasmanian emu specimens will hopefully provide more data, so watch this space!

Several authors have assumed that emus preferred open woodland habitat. The tragic explorer Henry Hellyer came across emu tracks near St Valentines Peak in 1827, which he took to indicate ‘better country’, that is, open country suitable for grazing sheep. Archaeologists have assumed that the presence of eggshells in ancient deposits indicates grassy, open vegetation nearby. However, Australian mainland emus are found in many different habitats, from open woodland to timbered areas, from near-desert to alpine scrub, from temperate to tropical climates and at all altitudes.

Importantly, we don’t know why the Tasmanian emus disappeared so quickly. Exploring historical texts and interviewing older Tasmanians in the 1920s, Stuart Dove decided that government-sponsored hunting was to blame. That’s a fair assumption given the intensity with which the animals were hunted:  One hunter claimed to have been delivering 1000 lb of emu and kangaroo flesh to the colonial stores every month. Europeans killed emus all year round, regardless of breeding seasons. This prompted a call for restrictions on the hunting of native fauna in the late 1830s but to no avail.

Hunting by colonial towns-folk was likely intense but other groups were pursuing the emu as well. There are several accounts of Aboriginal groups with enormous packs of dogs. Bushrangers were living off the land and likely took much of their sustenance from hunting. Emus were known to feed on grain crops and farmers likely killed them to protect their livelihoods.

Aside from hunting there are several other factors that have not yet been systematically considered. Settlers reported unowned dogs attacking sheep. Those dogs may have also depredated emus far from settled areas, although it is puzzling that emus have lived alongside dingoes on the mainland of Australia for at least three thousand years. Robert Dooley has hypothesised that introduced rats devoured emu eggs. Pigs may have attacked eggs and chicks. Herds of free-roaming cattle and sheep would have competed with emus for food. Tasmanian wedge-tailed eagles are known to be susceptible to having their nests disturbed – perhaps Tasmanian emus were similarly sensitive in some way. No one has considered whether a disease could have affected emus, though there is no particular reason to think so.

A likely factor is the loss of emu habitat. Van Diemen’s Land changed very quickly after colonisation. By the 1830s, large areas around the Derwent River, the Tamar River, the Midlands and the central north coast had been settled. If the land taken for cropping and grazing overlapped with the heart of emu habitat then it may have had a severe impact on the emu population. I’m hoping to test that hypothesis using data collected from the early accounts of settlers, explorers and naturalists.

On the other hand, there were still vast areas of Tasmania, far from settlements, which remained uncleared for decades. If the thylacine could take refuge in the wilder corners of Tasmania then why not the emu? A report by the pioneering Tasmanian botanist Ronald Gunn gives us a clue. In 1860, Gunn stood on a hill near the Leven River and saw that the country had not been burned for twenty-five years or more. What had once been open grassy plains was thick with young eucalypts and would soon be unsuitable for pasture. Gunn wrote that “the want of the usual and regular aboriginal fires to clear the country seems to be the cause.”

Almost immediately upon the arrival of the British in Van Diemen’s Land, Aboriginal people were prevented from caring for their country in ways that had sustained it for millenia. This included burning vegetation to clear pathways, to assist in hunting and to provide feeding grounds for herbivores. Were the Tasmanian emus deprived of refuge? Was that the final straw?

 

(All posts are personal reflections of the blog-post author and do not necessarily reflect the views of all other DEEP members).