Bear bile farms, which exist in some Asian countries like Vietnam and China, are a terrible reality for Asiatic black bears (Ursus thibetanus).
The bears spend their lives confined in tiny steel or concrete cages. They are “milked” through permanent holes in their side that allow bile to be extracted from the gall bladder.
My research, published in the journal Animal Welfare, investigated the chronic stress created by these conditions. We found that with care and rehabilitation, rescued bears in animal sanctuaries can readjust to a normal lifestyle with a reduction in stress – a highly encouraging result.
Because of this, bear bile is highly sought in traditional Chinese medicine. It is believed to reduce gall stones and improve indigestion, among other things. However, non-animal-derived and synthetic alternatives exist for urosodeoxycholic acid and other bile components.
The use of Asiatic black bears as primary sources of bile is a significant animal welfare problem that needs global awareness. Most of the bears are introduced to the trade upon poaching from the wild, and cubs as young as a few months are caged and held captive for up to 30 years.
My research investigated how successful this rehabilitation is, and whether rescued bears can recover from their experiences.
Animal cruelty causes chronic stress
Stress is defined as any unpleasant physical or psychological change that creates an uncomfortable feeling and negative outcome.
Not surprisingly, bears at bile farms in Vietnam have significantly higher levels of stress hormones than bears living in sanctuaries. This is the first scientific evidence of the chronic stress created by bear bile farming.
Stress in vertebrates (like humans and bears) is a physiological response in the endocrine system, also known as the hypothalamus-pituitary adrenal axis. This is the body’s main control centre for all things related to stress.
Stress hormones like cortisol help regulate the metabolism, especially in times of short-term or acute stress such as “fight or flight” situations. In normal situations, sharp stress causes an increase of cortisol that allows an animal to react quickly to a dangerous situation. Once the danger passes, a negative feedback loop reduces cortisol production and keeps the body stable.
But chronic stress can lead to harmful changes in the stress endocrine system. Long-term cortisol overproduction weakens the body’s ability to fend off daily challenges, and increases the risk of disease and death. In humans, chronic stress contributes to problems with the cardiovascular, immune and central nervous systems.
We measured cortisol levels in bear faeces to rapidly and reliably check their stress levels.
This was particularly useful because we did not have to restrain the rescued bears, a process that would understandably upset them more than their peers.
Reversing chronic stress in bear sanctuaries
Chronic stress is a massive challenge for the successful rehabilitation of animals into their new environment. Careful monitoring of stress is essential in animal rescue and translocation programs because it can provide information on the physiological resilience of each animal, and help rescuers understand how the animals might respond to humane interventions and veterinary checks.
Rescued bears are given special veterinary care and integrated into the bear sanctuary after several months of careful physiological and behavioural assessments.
Our data show that although not all bears fully recover from living on a bile farm, they generally manage to reduce their stress hormone levels under the rehabilitation program.
Back in 2008, only one-third of farmers accepted the science of climate change. Our 2010-11 survey of 946 irrigators in the southern Murray-Darling Basin (published in 2013) found similar results: 32% accepted that climate change posed a risk to their region; half disagreed; and 18% did not know.
Our latest preliminary research results have also revealed evidence of this change. We surveyed 1,000 irrigators in 2015-16 in the southern Murray-Darling Basin, and found attitudes have shifted significantly since the 2010 survey.
Now, 43% of farmers accept climate change poses a risk to their region, compared with just 32% five years earlier. Those not accepting correspondingly fell to 36%, while the percentage who did not know slightly increased to 21%.
Why would farmers deny the science?
There are many factors that influence a person’s denial of climate change, with gender, race, education and age all playing a part. While this partly explains the attitudes that persist among farmers (who tend to be predominantly male, older, Caucasian, and have less formal education), it is not the full story.
The very fact that farmers are on the front line of climate change also drives their climate change denial. For a farmer, accepting the science means facing up to the prospect of a harsher, more uncertain future.
Yet as these changes move from future prospect to current reality, they can also have a galvanising effect. Our survey results suggest farmers who have seen their farm’s productivity decrease over time are more likely to accept the science of climate change.
Many farmers who have turned to regenerative, organic or biodynamic agriculture talk about the change of mindset they went through as they realised they could no longer manage a drying landscape without major changes to their farming practices.
In addition, we have found another characteristic that is associated with climate change denial is whether farmers have identified a successor for their farm. Many farmers desire to turn their farm over to the next generation, hopefully in a better state than how they received the farm. This is where the psychological aspect of increased future uncertainty plays an important role – farmers don’t want to believe their children will face a worse future on the farm.
We all want our children to have better lives than our own, and for farmers in particular, accepting climate change makes that very challenging. But it can also prompt stronger advocacy for doing something about it before it’s too late.
What can we do?
Whether farmers do or do not accept climate change, they all have to deal with the uncertainty of weather – and indeed they have been doing so for a very long time. The question is, can we help them to do it better? Given the term “climate change” can be polarising, explicit climate information campaigns will not necessarily deliver the desired results.
What farmers need are policies to help them manage risk and improve their decision-making. This can be done by focusing on how adaptation to weather variability can increase profitability and strengthen the farm’s long-term viability.
Farming policy should be more strategic and forward-thinking; subsidies should be removed for unsustainable practices; and farmers should be rewarded for good land management – both before and during droughts. The quest remains to minimise the pain suffered by all in times of drought.
Humans may be Earth’s apex predator, but the fleeting shadow of a vulture or the glimpse of a big cat can cause instinctive fear and disdain. But new evidence suggests that predators and scavengers are much more beneficial to humans than commonly believed, and that their loss may have greater consequences than we have imagined.
In a recent paper in Nature Ecology & Evolution, we summarised recent studies across the globe looking at the services predators and scavengers can provide, from waste disposal to reducing car crashes.
The many roles our fanged friends play
Animals that eat meat play vital roles in our ecosystems. One of the most outstanding examples we found was that of agricultural services by flying predators, such as insectivorous birds and bats.
We found studies that showed bats saving US corn farmers over US$1 billion in pest control because they consume pest moths and beetles. Similarly, we found that without birds and bats in coffee plantations of Sulawesi, coffee profits are reduced by US$730 per hectare.
It’s not just birds and bats that help farmers. In Australia, dingoes increase cattle productivity by reducing kangaroo populations that compete for rangeland grasses (even when accounting for dingoes eating cattle calves).
This challenges the notion that dingoes are solely vermin. Rather, they provide a mixture of both costs and benefits, and in some cases their benefits outweigh the costs. This is particularly important as dingoes have been a source of conflict for decades.
One piece of research showed that if mountain lions were recolonised in the eastern United States, they would prey on enough deer to reduce deer-vehicle collisions by 22% a year. This would save 150 lives and more than US$2 billion in damages.
Weighing up the costs and benefits
Although these species provide clear benefits, there are well known costs associated with predators and scavengers as well. Many predators and scavengers are a source of conflict, whether it is perceived or real; particularly pertinent in Australia is the ongoing debate over the risk of shark attacks.
These drastic costs of predators and scavengers are rare, yet they attract rapt media attention. Nevertheless, many predators and scavengers are rapidly declining due to their poor reputation, habitat loss and a changing climate.
It’s time for a change in the conservation conversation to move from simply discussing the societal costs of predators and scavengers to a serious discussion of the important services that these animals provide in areas we share. Even though we may rightly or wrongly fear these species, there’s no doubt that we need them.
The authors would like to acknowledge the contributions of Dr Hawthorne Beyer and Alexander Braczkowski.
My (DM’s) perception of threatened species habitats changed the first time I encountered a population of endangered lizards living under small surface rocks in a heavily cleared grazing paddock. That was 20 years ago, at a time when land managers were well aware of the biodiversity values of conservation reserves and remnant patches of native vegetation. But back then we knew very little about the biodiversity values of the agricultural parts of the landscape.
Much has changed. Research has clearly shown the important ecological roles of different elements of the landscape for maintaining biodiversity on farms, especially for vertebrates such as carnivorous marsupials, frogs, snakes and lizards. Rocky outcrops and areas of surface rock, often termed bush rock, are among them.
Areas of bush rock are biological hotspots. They represent island refuges for specialised plants and animals, and help ecosystems to thrive even in heavily cleared landscapes. In Australia, more than 200 vertebrate species depend on rocky outcrops to survive, and many of these species are found only in agricultural areas.
Recent surveys by The Australian National University on working farms in New South Wales found new populations of the threatened Pink-tailed Worm-lizard. Rocky outcrops and surface bush rock are the reason these reptiles can keep living in grazing landscapes.
Unfortunately, these critical habitats get little protection in agricultural regions. Rocky habitats may look tough, but they are fragile ecosystems and are easily damaged. Vast areas of surface rock have been removed and previously undisturbed outcrops are at risk of being destroyed by legal and routine farming activities.
The new wave of habitat loss
Licensed operators have been removing bush rock for use in landscape gardening for several decades. This is of growing concern, but is not a new threat to our native wildlife. Instead, more sophisticated technology is being developed which turns vast tracts of rocky country into farmland by crushing and destroying surface rock within minutes.
Across Australia, heavy duty sleds are being towed behind tractors to rip and remove rocky breakaways, ridgelines and small outcrops. The machinery operates like a large cheese grater, ripping bedrock with a row of tines, then crushing the displaced rocks with a large roller. These machines are designed to process large areas at once and can crush an entire hectare of rock every hour.
Large areas of Western Australia, South Australia and western Victoria have been subject to widespread rock removal using these machines. This increasing agricultural practice has largely gone unnoticed.
While not illegal, rock-crushing has massive implications for the populations of native mammals, frogs and reptiles in agricultural areas. This approach to farming is at odds with the principle of land sharing, which encourages agriculture and wildlife conservation on the same land. Pressure to maximise productivity by increasing crop yields and intensifying land use could spell disaster for native species that live in these landscapes.
Some argue that using this new technology reduces soil damage by minimising how often agricultural machinery passes over the land. But this is not enough to offset the loss of this critical habitat. Surely we should be trying to find ways to protect and manage these environments in our cropping landscapes rather than developing ways to destroy them?
A gap in the law
The removal of bush rock is listed as a key threatening process under the Threatened Species Conservation Act 1995. However, this does not include the removal of rock where it is necessary for carrying out a development or activity with an existing approval under the Environmental Planning and Assessment Act. Nor does it prevent the removal of rock from paddocks when it is a necessary part of routine agricultural activity.
This loophole in the legislation could spell disaster for threatened species that rely on bush rock on private property to survive. For example, the Grassland Earless Dragon is thought to have gone extinct in Victoria as a result of habitat loss, including the removal of critical surface rock habitat from across its former range.
It would be a real shame to lose more threatened species to poorly planned and completely avoidable agricultural practices – especially when so many progressive landholders are actively trying to restore and improve biodiversity on the land.
National Party MP George Christensen has invited other Nationals to join the recently formed pro-coal “Monash Forum”. But is coal in the best interests of their rural constituents, particularly farmers?
Farmers stand to lose from any weakening of the government’s climate change policies. That is why farmers and their political representatives should be concerned about a current review of the government’s greenhouse gas reduction policy.
What is at stake here is the strange-sounding idea of carbon farming. To explain this idea takes several steps, so bear with me.
The policy under review is a legacy of the Abbott era. As prime minister, Tony Abbott abolished the carbon tax and replaced it with an Emissions Reduction Fund (ERF). The ERF was to be used to pay businesses to reduce their carbon emissions, or to capture and sequester (store) carbon dioxide already in the atmosphere.
regenerating native forest on previously cleared land
changed farming practices to allow for crop stubble retention
capturing and destroying the methane from effluent waste at piggeries.
How does carbon farming work?
To make it all work, the government first created the system of Australian Carbon Credit Units (ACCUs). This system commodifies the outputs of carbon farming, so these can be traded.
In this system, a carbon farmer must show either a reduction in emissions, or carbon sequestration (or ideally both), according to clearly specified criteria. The government will then issue (free of charge) one credit for every tonne of carbon dioxide (CO₂) – or CO₂ equivalent – abated in this way. Farmers can then sell these credits, thus receiving a direct financial return for their efforts.
The primary buyer of ACCUs at the moment is the government, via its Emissions Reduction Fund. Farmers (individually or as collectives) who want to embark on carbon farming projects are asked to nominate a price they would need to make it profitable for them to go ahead with the project. Through a reverse auction, the fund selects the lowest-price proposals.
In this way, the government gets the greatest carbon abatement for the least money. Successful bidders embark on their projects knowing that they have a guaranteed price for their carbon abatement outcomes. There is nothing magical or mystical about it. It is simply the price at which the buyer and sellers of carbon credits find it mutually advantageous to do business.
The average price paid at the last auction round was A$12 per tonne of CO₂ abated. This is the current carbon price in this particular market.
The Safeguard Mechanism
A second potential set of buyers of carbon credits was created by the Safeguard Mechanism, introduced by the Abbott government. This caps emissions from big industrial emitters in order to to ensure that abatement achieved by the ERF is not offset or cancelled out.
The cap is set at whatever the maximum emission rate from the emitter has been. So it is not designed to reduce emissions from these big emitters, but simply to hold them to current levels.
This policy is now beginning to bite. The government has just announced that in the first period for which the policy has been in effect, some 16 large emitters were in excess and had to buy 448,000 carbon credits to remain in compliance. Among the biggest buyers were:
Anglo Coal’s Capcoal mining operations
Glencore’s Tahmoor Coal
Rio Tinto’s Alcan Gove aluminium operations
BHP Billiton Mitsubishi Coal/BM Alliance.
These companies bought their credits from carbon farmers who abated more carbon then they had calculated, and so had a surplus left over for sale.
But what is most interesting is the price that excess emitters were willing to pay for the surplus credits. Most of the sales were in the region of $14-15 per tonne (T), but the price rose to $17-18/T as the deadline approached.
This means that the price spiked at 50% higher than the most recent ERF auction price of $12/T.
Commentators describe this as a secondary market, and the price in this market is exciting news for carbon farmers. According to Australian Carbon Market Institute CEO Peter Castellas, “Australia now has a functioning carbon market.” Carbon farmers – who make up an increasing proportion of the Nationals’ constituency – will do well if this market expands.
One way to develop the market would be to slowly lower the caps on big emitters so they must either buy more carbon credits or find ways to reduce their own emissions.
From this point of view, there is good reason to progressively and predictably reduce the emissions allowed under the Safeguard Mechanism.
The current review
Here’s where we get to the current review. As already noted, the Safeguard Mechanism does not seek to reduce emissions from big emitters. In fact, it allows for an increase in emissions to accommodate business growth. Nevertheless, big emitters are still unhappy.
The government’s review is a response to business concerns. An initial consultation paper has proposed making it easier to raise the cap on a company’s emissions as its activity grows.
If the rules are altered in this way, the demand for carbon credits may stall, and even decline, bringing to an end to this promising new source of revenue for farmers.
That is why members of parliament with rural constituencies should take note. Rural MPs should not sit by and allow the government to respond to the interests of the coal industry and other lobby groups.
Carbon farming depends on reducing the caps under the Safeguard Mechanism, not raising them. This would also be a step in the direction of achieving the emissions reduction target to which Australia agreed at the Paris meetings in 2015.
Bren Smith, an ex-industrial trawler man, operates a farm in Long Island Sound, near New Haven, Connecticut. Fish are not the focus of his new enterprise, but rather kelp and high-value shellfish. The seaweed and mussels grow on floating ropes, from which hang baskets filled with scallops and oysters. The technology allows for the production of about 40 tonnes of kelp and a million bivalves per hectare per year.
The kelp draw in so much carbon dioxide that they help de-acidify the water, providing an ideal environment for shell growth. The CO₂ is taken out of the water in much the same way that a land plant takes CO₂ out of the air. But because CO₂ has an acidifying effect on seawater, as the kelp absorb the CO₂ the water becomes less acid. And the kelp itself has some value as a feedstock in agriculture and various industrial purposes.
After starting his farm in 2011, Smith lost 90% of his crop twice – when the region was hit by hurricanes Irene and Sandy – but he persisted, and
now runs a profitable business.
His team at 3D Ocean Farming believe so strongly in the environmental and economic benefits of their model that, in order to help others establish similar operations, they have established a not-for-profit called Green Wave. Green Wave’s vision is to create clusters of kelp-and-shellfish farms utilising the entire water column, which are strategically located near seafood transporting or consumption hubs.
The general concepts embodied by 3D Ocean Farming have long been practised in China, where over 500 square kilometres of seaweed farms exist in the Yellow Sea. The seaweed farms buffer the ocean’s growing acidity and provide ideal conditions for the cultivation of a variety of shellfish. Despite the huge expansion in aquaculture, and the experiences gained in the United States and China of integrating kelp into sustainable marine farms, this farming methodology is still at an early stage of development.
Yet it seems inevitable that a new generation of ocean farming will build on the experiences gained in these enterprises to develop a method of aquaculture with the potential not only to feed humanity, but to play a large role in solving one of our most dire issues – climate change.
Globally, around 12 million tonnes of seaweed is grown and harvested annually, about three-quarters of which comes from China. The current market value of the global crop is between US$5 billion and US$5.6 billion, of which US$5 billion comes from sale for human consumption. Production, however, is expanding very rapidly.
Seaweeds can grow very fast – at rates more than 30 times those of land-based plants. Because they de-acidify seawater, making it easier for anything with a shell to grow, they are also the key to shellfish production. And by drawing CO₂
out of the ocean waters (thereby allowing the oceans to absorb more CO₂ from the atmosphere) they help fight climate change.
The stupendous potential of seaweed farming as a tool to combat climate change was outlined in 2012 by the University of the South Pacific’s Dr Antoine De Ramon N’Yeurt and his team. Their analysis reveals that if 9% of the ocean were to be covered in seaweed farms, the farmed seaweed could produce 12 gigatonnes per year of biodigested methane which could be burned as a substitute for natural gas. The seaweed growth involved would capture 19 gigatonnes of CO₂. A further 34 gigatonnes per year of CO₂ could be taken from the atmosphere if the methane is burned to generate electricity and the CO₂ generated captured and stored. This, they say:
…could produce sufficient biomethane to replace all of today’s needs in fossil-fuel energy, while removing 53 billion tonnes of CO₂ per year from
the atmosphere… This amount of biomass could also increase sustainable fish production to potentially provide 200 kilograms per year, per person, for 10 billion people. Additional benefits are reduction in ocean acidification and increased ocean primary productivity and biodiversity.
Nine per cent of the world’s oceans is not a small area. It is equivalent to about four and a half times the area of Australia. But even at smaller scales,
kelp farming has the potential to substantially lower atmospheric CO₂, and this realisation has had an energising impact on the research and commercial
development of sustainable aquaculture. But kelp farming is not solely about reducing CO₂. In fact, it is being driven, from a commercial perspective, by sustainable production of high-quality protein.
What might a kelp farming facility of the future look like? Dr Brian von Hertzen of the Climate Foundation has outlined one vision: a frame structure, most likely composed of a carbon polymer, up to a square kilometre in extent and sunk far enough below the surface (about 25 metres) to avoid being a shipping hazard. Planted with kelp, the frame would be interspersed with containers for shellfish and other kinds of fish as well. There would be no netting, but a kind of free-range aquaculture based on providing habitat to keep fish on location. Robotic removal of encrusting organisms would probably also be part of the facility. The marine permaculture would be designed to clip the bottom of the waves during heavy seas. Below it, a pipe reaching down to 200–500 metres would bring cool, nutrient-rich water to the frame, where it would be reticulated over the growing kelp.
Von Herzen’s objective is to create what he calls “permaculture arrays” – marine permaculture at a scale that will have an impact on the climate by growing kelp and bringing cooler ocean water to the surface. His vision also entails providing habitat for fish, generating food, feedstocks for animals, fertiliser and biofuels. He also hopes to help exploited fish populations rebound and to create jobs. “Given the transformative effect that marine permaculture can have on the ocean, there is much reason for hope that permaculture arrays can play a major part in globally balancing carbon,” he says.
The addition of a floating platform supporting solar panels, facilities such as accommodation (if the farms are not fully automated), refrigeration and processing equipment tethered to the floating framework would enhance the efficiency and viability of the permaculture arrays, as well as a dock for ships
carrying produce to market.
Given its phenomenal growth rate, the kelp could be cut on a 90-day rotation basis. It’s possible that the only processing required would be the cutting of the kelp from the buoyancy devices and the disposal of the fronds overboard to sink. Once in the ocean depths, the carbon the kelp contains is essentially out of circulation and cannot return to the atmosphere.
The deep waters of the central Pacific are exceptionally still. A friend who explores mid-ocean ridges in a submersible once told me about filleting a fish for dinner, then discovering the filleted remains the next morning, four kilometres down and directly below his ship. So it’s likely that the seaweed fronds would sink, at least initially, though gases from decomposition may later cause some to rise if they are not consumed quickly. Alternatively, the seaweed
could be converted to biochar to produce energy and the char pelletised and discarded overboard. Char, having a mineralised carbon structure, is likely to last well on the seafloor. Likewise, shells and any encrusting organisms could be sunk as a carbon store.
Once at the bottom of the sea three or more kilometres below, it’s likely that raw kelp, and possibly even to some extent biochar, would be utilised as a food source by bottom-dwelling bacteria and larger organisms such as sea cucumbers. Provided that the decomposing material did not float, this would not matter, because once sunk below about one kilometre from the surface, the carbon in these materials would effectively be removed from the atmosphere for at least 1,000 years. If present in large volumes, however, decomposing matter may reduce oxygen levels in the surrounding seawater.
Large volumes of kelp already reach the ocean floor. Storms in the North Atlantic may deliver enormous volumes of kelp – by some estimates as much as 7 gigatonnes at a time – to the 1.8km-deep ocean floor off the Bahamian Shelf.
Submarine canyons may also convey large volumes at a more regular rate to the deep ocean floor. The Carmel Canyon, off California, for example, exports large volumes of giant kelp to the ocean depths, and 660 major submarine canyons have been documented worldwide, suggesting that canyons play a significant role in marine carbon transport.
These natural instances of large-scale sequestration of kelp in the deep ocean offer splendid opportunities to investigate the fate of kelp, and the carbon it contains, in the ocean. They should prepare us well in anticipating any negative or indeed positive impacts on the ocean deep of offshore kelp farming.
Only entrepreneurs with vision and deep pockets could make such mid-ocean kelp farming a reality. But of course where there are great rewards, there are also considerable risks. One obstacle potential entrepreneurs need not fear, however, is bureaucratic red tape, for much of the mid-oceans remain a global commons. If a global carbon price is ever introduced, the exercise of disposing of the carbon captured by the kelp would transform that part of the business from a small cost to a profit generator. Even without a carbon price, the opportunity to supply huge volumes of high-quality seafood at the same time as making a substantial impact on the climate crisis are considerable incentives for investment in seaweed farming.
Climate change and extreme weather events are already impacting our food, from meat and vegetables, right through to wine. In our series on the Climate and Food, we’re looking at what this means for the food chain.
The concentration of carbon dioxide in our atmosphere is increasing. Everything else being equal, higher CO₂ levels will increase the yields of major crops such as wheat, barley and pulses. But the trade-off is a hit to the quality and nutritional content of some of our favourite foods.
In our research at the Australian Grains Free Air CO₂ Enrichment (AGFACE) facility, we at Agriculture Victoria and The University of Melbourne are mimicking the CO₂ levels likely to be found in the year 2050. CO₂ levels currently stand at 406 parts per million (PPM) and are expected to rise to 550PPM by 2050. We have found that elevated levels of CO₂ will reduce the concentration of grain protein and micronutrients like zinc and iron, in cereals (pulses are less affected).
The degree to which protein is affected by CO₂ depends on the temperature and available water. In wet years there will be a smaller impact than in drier years. But over nine years of research we have shown that the average decrease in grain protein content is 6% when there is elevated CO₂.
Because a decrease in protein content under elevated CO2 can be more severe in dry conditions, Australia could be particularly affected. Unless ways are found to ameliorate the decrease in protein through plant breeding and agronomy, Australia’s dry conditions may put it at a competitive disadvantage, since grain quality is likely to decrease more than in other parts of the world with more favourable growing conditions.
There are several different classes of wheat – some are good for making bread, others for noodles etc. The amount of protein is one of the factors that sets some wheat apart from others.
Although a 6% average decrease in grain protein content may not seem large, it could result in a lot of Australian wheat being downgraded. Some regions may be completely unable to grow wheat of high enough quality to make bread.
But the protein reduction in our wheat will become manifest in a number of ways. As many farmers are paid premiums for high protein concentrations, their incomes could suffer. Our exports will also take a hit, as markets prefer high-protein wheat. For consumers, we could see the reduction in bread quality (the best bread flours are high-protein) and nutrition. Loaf volume and texture may be different but it is unclear whether taste will be affected.
The main measure of this is loaf volume and texture, but the degree of decrease is affected by crop variety. A decrease in grain protein concentration is one factor affecting loaf volume, but dough characteristics (such as elasticity) are also degraded by changes in the protein make-up of grain. This alters the composition of glutenin and gliadin proteins which are the predominant proteins in gluten. To maintain bread quality when lower quality flour is used, bakers can add gluten, but if gluten characteristics are changed, this may not achieve the desired dough characteristics for high quality bread. Even if adding extra gluten remedies poor loaf quality, it adds extra expense to the baking process.
Nutrition will also be affected by reduced grain protein, particularly in developing areas with more limited access to food. This is a major food security concern. If grain protein concentration decreases, people with less access to food may need to consume more (at more cost) in order to meet their basic nutritional needs. Reduced micronutrients, notably zinc and iron, could affect health, particularly in Africa. This is being addressed by international efforts biofortification and selection of iron and zinc rich varieties, but it is unknown whether such efforts will be successful as CO₂ levels increase.
What can we do about it?
Farmers have always been adaptive and responsive to changes and it is possible management of nitrogen fertilisers could minimise the reduction in grain protein. Research we are conducting shows, however, that adding additional fertiliser has less effect under elevated CO₂ conditions than under current CO₂ levels. There may be fundamental physiological changes and bottlenecks under elevated CO₂ that are not yet well understood.
If management through nitrogen-based fertilisation either cannot, or can only partly, increases grain protein, then we must question whether plant breeding can keep up with the rapid increase in CO₂. Are there traits that are not being considered but that could optimise the positives and reduce the negative impacts?
Selection for high protein wheat varieties often results in a decrease in yield. This relationship is referred to as the yield-protein conundrum. A lot of effort has gone into finding varieties that increase protein while maintaining yields. We have yet to find real success down this path.
A combination of management adaptation and breeding may be able to maintain grain protein while still increasing yields. But, there are unknowns under elevated CO₂such as whether protein make-up is altered, and whether there are limitations in the plant to how protein is manufactured under elevated CO2. We may require active selection and more extensive testing of traits and management practices to understand whether varieties selected now will still respond as expected under future CO₂ conditions.
Finally, to maintain bread quality we should rethink our intentions. Not all wheat needs to be destined for bread. But, for Australia to remain competitive in international markets, plant breeders may need to select varieties with higher grain protein concentrations under elevated CO2 conditions, focusing on varieties that contain the specific gluten protein combinations necessary for a delicious loaf.
European colonisation brought a different and more pervasive change, clearing land, building cities, damming rivers and establishing an increasingly mechanised and industrialised agriculture.
These iconic but changed landscapes inspired the romantic art of Arthur Streeton and poetry of Banjo Paterson among many others — and helped forge a young nation’s identity.
Change can happen surprisingly quickly. Often before we know it we’ve gone too far and need to scramble for fixes that are so often costly, slow and ultimately inadequate.
For example, in South Australia, researchers in the early 1960s raised the alarm that the feverish post-war period of soldier resettlement, land clearance and agricultural development threatened entire native plant and animal communities with extinction. The government’s response over the following 30 years was to expand greatly the conservation reserve network and eventually prohibit land clearing.
Is the balance right? Opinion varies. Many would say no, and consider the status quo to be stacked strongly against the environment.
Others see agriculture as entering a boom time, driven by growing population and rising food prices. Substantial interest from overseas investors in Australian agricultural land reflects this opportunity.
Demand for more secure sources of energy has generated rapid expansion of coal seam gas and wind power generation, and the development of northern Australia remains a bipartisan priority.
Worldwide, Australia is not alone — many international examples also exist of recent, massive, rapid and accelerating changes in how land is used.
Australia has historically taken a hands-off approach to managing land use change, instead focusing on increasing the productivity and competitiveness of agriculture. Apart from a handful of planning and environmental regulations, the use of land has been subject to minimal governance or strategic direction.
Where to from here?
What is it that Australians really want from our land? We know what we don’t want: wall-to-wall crops, pasture, buildings, gas wells, mines, wind farms or trees.
We can expect healthy debate around the margins, but, in general, diversity, productivity and sustainability seem to be widely valued. Most of us want to leave the place in decent condition for future generations.
Europe has had this conversation and knows what it wants from its landscapes — and it’s not afraid to pay for it (for instance, through agricultural subsidies). A deep aesthetic and cultural heritage is the central objective, with a balance of recreation opportunities, tourism, a clean and healthy environment and high-quality produce all being high priorities.
Once we know what we want, we can work out how to get there.
CSIRO’s recent National Outlook mapped Australia’s potential future pathways. A companion paper in Nature found that it is possible to achieve strong economic growth and reduce environmental pressure, if we put the right policies in place now. It provides a glimpse of how our rural lands might respond to coalescing future change pressures.
Who knows? A pay rise while watching trees grow could be an attractive proposition for our ageing farmers. Complementary biodiversity payments could also help arrest declines in wildlife and help it adapt to climate change.
But trade-offs are likely. Trees use a lot more water than crops and pasture, so we will need to think carefully about managing water resources.
Australians care about their land and are more aware than ever about what is happening to it. While we can have some control over the future of our land, and we do exercise this control in certain circumstances (such as urban planning), our long-term approach to rural land has been to let environmental and economic forces play out and let the invisible hand of economics determine what will be.
Given the pace at which change can happen, a smarter approach will be to start the conversation, work out what it is we want from our land, and put the policies and institutions in place to get us there.
Agricultural research and management programs often deal with these interactions by focusing on simplistic “good” and “bad” labels: aphids are annoying pests, for example, whereas bees are little angels.
In reality, however, no animal is 100% a “goodie” or “baddie” – their effects on crop production vary with context. Interactions between animals and crops are influenced by seasons, landscapes, management practices, and other animals. They can also be affected by the social, cultural and economic values of the local farming community. The same species can be “good” in one system and “bad” in another.
It sounds complicated, because it is. But this is where ecological research can help. Understanding the interplay between these factors will help ensure that farms can protect wildlife while also providing us with food and other resources.
Good versus bad?
When we reviewed 281 papers that evaluated increases or reductions in crop yields due to wild birds or insects on farms, we found that the binary view of “good” and “bad” animals is still widespread.
Of the studies we looked at, 53% (mostly in the agricultural sciences) focused on identifying and managing the “baddies”, by weighing up costs that animals create for farmers by damaging crops. Another 38% (mostly ecology and conservation studies) calculated the impact of the “goodies”: benefits such as pollination and pest control. Only 9% of the studies we reviewed considered both costs and benefits in a single system.
This shows that most scientific studies are still taking an approach that is too simplistic. Attempting to link increases or reductions in crop yields with a single pest or helper species doesn’t usually tell the whole story. It doesn’t tell us about other factors that influence crop yields, like seasonal changes in animal activity, effects of different management practices, or interactions between different animal species.
Because so many studies have focused on quantifying the effect of one group of animals (such as bees), or focused on effects at one crop development stage (for example, using fruit set as an indicator of pollination efficiency), the overall body of knowledge on how wild animals affect crops has become disjointed and sometimes contradictory.
In a second paper, we suggest a new way to address these complex issues that considers the social and environmental contexts of crop production across the entire growing season. By looking at the interplay between the various positive and negative effects, we can gain a more realistic estimate of how crop yields are affected by wild animals.
Here’s an example. In Australian almond orchards, native birds are often considered pests because they can cause crop losses by pecking at developing fruit. But after harvest has finished, the same birds also remove the decaying “mummy” nuts left on trees. Growers sometimes use paid manual labour to remove these nuts, because they harbour disease and pests that can damage the trees.
A cost-benefit analysis of shows that the positive economic value of the birds cleaning up the mummy nuts outweighs the cost of crop losses from damaged almonds. Averaged across the entire plantation, the presence of the birds is a net positive for farmers. This means that letting birds do their thing could be more cost-effective for growers than deterring the birds and then paying people to remove the mummy nuts. But without this cost-benefit approach, it easy to imagine how farmers would persist in viewing the birds as crop pests and shooing them away.
Very few studies have considered how wild animals create this type of cost-benefit trade-off in farming ecosystems. Yet this approach is central to the study of ecology, and there are obvious parallels between natural and agricultural systems. Both, for instance, have pollination and pest control as key functions.
Productive farms have complex cycles of interactions between crops, wild animals and people. These cycles need to be sustained, not isolated from the system. As with any ecosystem, understanding is the first step towards protection.