Category Archives: Climate change

What to do in a heatwave during a time of pandemic crisis and climate emergency

2020-08-11 20.30.06

Stay alert

Stay calm

Stay cool

Don’t melt

Stay aler

Stay cal

Stay coo

Don’t melt

Stay ale

Stay ca

Stay co

Don’t melt

Stay al

Stay c

Stay c

Don’t melt

Stay a

Stay

Stay

Don’t melt

Stay

Sta

Sta

Don’t melt

Sta

St

St

Don’t melt

St

S

S

Don’t melt

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Don’t melt

Don’t

Don’…..

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Filed under Climate change, Poetry

Get a 30% discount if you pre-order my new book Pollinators & Pollination: Nature and Society

PollinatorsandPollination-frontcover

In the next few months my new book Pollinators & Pollination: Nature and Society will be published.  As you can imagine, I’m very excited! The book is currently available to pre-order: you can find full details here at the Pelagic Publishing website.  If you do pre-order it you can claim a 30% discount by using the pre-publication offer code POLLINATOR.

As with my blog, the book is aimed at a very broad audience including the interested public, gardeners, conservationists, and scientists working in the various sub-fields of pollinator and pollination research. The chapter titles are as follows:

Preface and Acknowledgements
1. The importance of pollinators and pollination
2. More than just bees: the diversity of pollinators
3. To be a flower
4. Fidelity and promiscuity in Darwin’s entangled bank
5. The evolution of pollination strategies
6. A matter of time: from daily cycles to climate change
7. Agricultural perspectives
8. Urban environments
9. The significance of gardens
10. Shifting fates of pollinators
11. New bees on the block
12. Managing, restoring and connecting habitats
13. The politics of pollination
14. Studying pollinators and pollination
References
Index

 

 

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Filed under Bees, Biodiversity, Biodiversity and culture, Birds, Butterflies, Climate change, Ecosystem services, Evolution, Flies, Gardens, History of science, Honey bees, Hoverflies, IPBES, Macroecology, Mammals, Moths, Mutualism, Neonicotinoids, Personal biodiversity, Pollination, Rewilding, Tenerife, Urban biodiversity

Ecologists in a time of COVID-19

20200311_140421

Yesterday I was involved in what’s likely to be be my last face-to-face teaching and meetings from some weeks, possibly months.  In the morning my colleague Duncan McCollin and I watched our final year students take part in an assessed debate that pitted two sides against one another to argue whether or not Brexit will have a negative effect on biodiversity.  The students did very well, they had a great grasp of the issues and the facts and figures.  The end result was very much a draw:

2020-03-16 10.35.33

Teaching at the University of Northampton will go online from the end of the week and a field trip for our first year undergraduates that we had planned for this Thursday has been pulled.  Our annual Tenerife Field Course has also been cancelled: this will be the first year since 2003 that I have not visited the island and it’s going to leave a hole in my long-term data sets.  Perhaps the universe is telling me that it’s time to write them up for publication?

Last week I did a quick vox pop on Twitter to ask how COVID-19 has affected ecology field work at other universities:

The response was interesting and it’s clear that overseas field courses have been massively impacted.  Following the UK Government’s advice yesterday about limiting social contact it seems that local field work for student groups will also be affected.  Hopefully those undertaking individual field work, especially PhD and postdoctoral researchers, will still be able to carry out their data collection.  Do let me know in the comments if it’s affecting your work.

There were also some Twitter responses from professional ecological consultants pointing out that they may not be able to carry out surveys of sites for planning and development purposes.  This is yet another way in which COVID-19 is going to impact our economy.

Following the student debate, Duncan and I headed out to catch up with a meeting of the steering group of the Chequered Skipper Reintroduction Project   We missed the morning’s presentations but arrived in time for the lunch and a short field trip:

2020-03-16 14.25.51

The location of the reintroduction is still being kept secret, as is a second site where a further reintroduction of butterflies from the Belgium population is being considered.  However there was much discussion as to whether restrictions on travel means that this would have to be delayed until next year.

On the way to that site, during a 15 minute drive, we spotted seven red kites.  They are now so common that seeing these amazing birds hardly requires comment.  But we should never forget what an incredibly successful conservation story this has been.  To cap it all, when we arrived at the site I had the pleasure of meeting Karl Ivens, one of the main drivers behind the reintroduction of red kites to Northamptonshire. He now estimates the regional population to be a couple of thousand birds.  The guy deserves a statue, or at least a blue plaque on his house!

On the way home I was thinking about my next blog post and what to write, and whether or not to bring the pandemic into it.  There’s a lot of information, and misinformation, about COVID-19 online and I’m not qualified to add to that: I’m not an epidemiologist.  However I’d like to link to a few things I think are worth reading.

Over at the Dynamic Ecology blog, Brian McGill has posted an open thread on ecologists discussing the coronavirus pandemic.  There are some interesting contributions in the comments, particularly around the response of the UK Government to the crisis.  I was struck by Jeremy Fox’s comment that Britain has some brilliant epidemiological modelers and that “even if you don’t think much of Boris Johnson or his senior advisers, the modelers who are feeding them information and advice are intellectually honest, hardworking, care deeply about protecting the public, and are as good at their jobs as anybody in the world.”  As I pointed out in a reply, this is undoubtedly true, but a lot depends on whether the government is willing to implement that advice. And its track record so far is not inspiring: for years it ignored expert advice on the effects of badger culling on the spread of bovine TB and continued to kill badgers. It’s only just reversed that decision.  Let’s hope that they have learned from that experience.

I am also hoping that there will be at least one positive outcome from the current pandemic on top of recent extreme weather patterns linked to climate change (for example the drought and fires in Australia that I blogged about in January).  I hope that it serves to  remind the public, governments and large corporations just how dependent on the environment our society is.  Despite our advanced technologies, we are incredibly sensitive to disruptions in the natural world.  As this old piece from the New York Times points out: “most epidemics — AIDS, Ebola, West Nile, SARS, Lyme disease and hundreds more that have occurred over the last several decades — don’t just happen. They are a result of things people do to nature“.   That was in 2012, long before COVID-19 was discovered.  To update this, check out the Wildlife Conservation Society’s ongoing series of articles about the relationship between our destruction of natural habitats, the trade in illegally (and legally) hunted animals, and emerging diseases such as COVID-19.

I realise that I’m fortunate and that there’s a lot that I can do by working from home.  For the next few weeks I’ll be doing just that, supporting students online, completing grant and manuscript reviews, having Zoom/Skype meetings, and completing the book that I am writing.  Stay safe everyone.

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Filed under Australia, Biodiversity, Butterflies, Climate change, University of Northampton

Forest restoration for climate change: don’t forget the pollinators and seed dispersers

2020-02-07 09.29.47

There’s been much discussion in the news and online recently about seed collecting, habitat restoration, and tree planting as a way of storing carbon in an effort to reduce the effects of climate change.  This is one of the (many) elements proposed by the recent Drawdown Framework.  In fact their “Table of Solutions” ranks tropical forest restoration in the top 5 to 10 ways of reducing CO2 in the atmosphere, and temperate forest restoration and planting in the top 20.

At one end of the spatial scale, Markus Eichhorn relates the story of his father’s obsession with collecting oak seedlings to reforest the local countryside.  At the other, there’s some very high profile forest restoration schemes going on at the moment; here’s a couple that immediately come to mind:

Grain for Green – China’s attempt to restore vegetation to abandoned farmland to reduce soil erosion and flooding.  According to the Wikipedia entry “Grain for Green has involved 124 million people in 1,897 counties in 25 provinces……. By 2010, around 15 million hectares of farmland and 17 million hectares of barren mountainous wasteland were converted back to natural vegetation”.

Great Green Wall – a multinational initiative in Africa aimed at restoring the vegetation on the southern edge of the Sahara to combat desertification and mitigate climate change.

Several countries have also made a great deal of noise about marshaling huge public efforts to plant hundreds of millions of trees in a single day,  for example India and Ethiopia.

These big schemes are all well and good: they generate a lot of publicity for actions on climate change and a warm, fuzzy feeling that governments and people are Doing Something.  But there’s a couple of problems.  First of all, planting trees is not enough: we could not plant enough trees in the world to reduce CO2 to pre-industrial levels.  Secondly, planted trees require nurturing.  It is not enough just to put in some young plants and hope for the best; a high proportion of trees die even when well looked after.  If they are just planted and ignored, who knows how many will survive?

However habitat restoration is important; it’s not a silver bullet solution to climate change, but it is part of our toolbox of Things We Can Do.  Just as importantly, restoring habitats provides more opportunities for species to move in response to changing climates, and to recolonise areas from where they have been extirpated.  And of course diverse, functioning ecosystems support human societies in ways both tangible and unquantifiable.

With all of this in mind I was interested to read a piece by John Carey in PNAS entitled   “The best strategy for using trees to improve climate and ecosystems? Go natural“. There’s some really inspiring stories in here, it’s well worth taking a look.  The main message of the article is that allowing forest vegetation to naturally regenerate, from seeds, and dormant roots and stumps, is by far the best way to ensure that trees survive and the restoration is successful.  However there’s something fundamental missing from that article: the role of species interactions in determining the survival of these forests over long time scales.

The vast majority of the world’s plants are animal pollinated; this includes trees.  Even in the UK where we often associate trees with wind pollination, about 65% of our native species are insect pollinated.  In the tropics this can rise to 100% of species within a community.  Although many of those trees can engage in some self-pollination, in the long term this is likely to result in genetic problems associated with inbreeding.  Outcrossing sex is common in plants for a good reason.

Similarly many trees require animals to move their offspring away from the parent plant.  This avoids competition between parent and offspring, and the impacts of diseases and pathogens caused by the Janzen-Connell Effect.  I don’t have any comparable statistics on the proportion of trees, regionally and globally, that use animals as seed dispersers (does anyone?  Please comment below if I’ve missed something).  But I’m willing to bet that it’s a high proportion.

Without pollinators and seed dispersers, restored forests will not flourish in the long term.  There seems to be an implicit assumption that once the forests are established, the pollinators and seed dispersers will follow.  That may be true up to a point, but it shouldn’t be taken for granted, particularly for isolated fragments of forest with no ecological connections to more established areas of woodland.  These are the aspects that are missing from John Carey’s (otherwise fine) article, and indeed from wider discussions about forest restoration and tree planting.  As so often when we talk about the conservation of biodiversity we neglect to consider the role of species interactions.  I’ve been trying to press home that point for years, on the blog and in papers, and I was pleased to see an interesting contribution to this topic by Pedro Luna and colleagues from Mexico on “Measuring and Linking the Missing Part of Biodiversity and Ecosystem Function: The Diversity of Biotic Interactions“.

Let’s not forget: species do not occur in isolation, and the biodiversity of species interactions in fundamental to the ecology of the planet.

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Impact of extreme events on pollinators: download it for free

SHOCKs image

In my last post I highlighted a couple of recent papers on climate change and extreme events, and how they impact pollinators.  The Erenler et al. (2020) mini-review paper that I mentioned has now been published and is available for free download for the next 50 days.  Follow the hot link here:

Erenler, H.E., Gillman, M.P. & Ollerton, J. (2020) Impact of extreme events on pollinator assemblages.  Current Opinion in Insect Science 38: 34-39

This review is one of several from a themed issue of Current Opinion in Insect Science devoted to Ecology.  The issue is edited by Tom Ings from Anglia Ruskin University and Sarah Arnold from University of Greenwich.

 

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Filed under Biodiversity, Climate change

Pollinators, climate change, and extreme events: two recent publications

SHOCKs image

Well, we’re back in the UK now and have just about got over the jet lag.  I’ve returned to teaching, admin, and meetings, and both Karin and I are trying to find time to finish our books.  But the persistent backdrop to our stay in Australia – the bushfires and the role of climate change, and the ensuing tensions between scientific evidence and politics – is still fresh in our minds.  It’s timely, then, to highlight two new papers that focus on extreme events, climate change and pollinators.  The first is one of my own, led by Dr Hilary Erenler who carried out her PhD research in my group.  It’s an invited mini-review in the journal Current Opinion in Insect Science entitled “Impact of extreme events on pollinator assemblages” (Erenler et al. 2020).  The review is available as a pre-print on the journal’s website; we’ve not yet even seen the proofs, though the final version should not be too different.  If you want a copy, just ask.

In this essay we focus on what we term SHOCKS: events that provide a Sudden, High-magnitude Opportunity for a Catastrophic ‘Kick’ to the environment that can negatively affect pollinator assemblages in many different ways.  Such events can be natural, human-mediated or human-enhanced, and occur suddenly, at a high-magnitude and with possibly catastrophic outcomes for those pollinators. There are many examples of such SHOCKs, as we illustrate in the figure above which comes from the paper.  However one of our main conclusions is just how little we understand about the outcomes of such events on pollinators.  Ideally we need before, during and after event monitoring to assess how pollinators have been affected and may respond.  But SHOCKs are, by their very nature, infrequent and unpredictable, and often we don’t have the baseline data with which to compare to post-event data.  I know from conversations with Australian pollination ecologists that some have had their field sites burned and they are going to use this as an opportunity to assess how the fires have impacted pollinators.  Field experiments such as the one by Biella et al. (2019) that I discussed last year, in which flowers were removed from a plant community, may also give us some insights into the response of plant-pollinator networks to sudden SHOCKs.  But we need more research focus on this topic, especially consideration of how the impacts of SHOCKs can be reduced and mitigated.

One set of emerging human-enhanced SHOCKs highlighted by Erenler et al. (2020) is extreme weather events that are being exacerbated (in scale or frequency) by anthropogenic climate change.  We cite several papers and reviews that have considered this, but there’s still few empirical studies that have actually looked at how weather SHOCKs might be impacting pollinators.  It’s therefore timely that this week’s Science includes a very impressive study of how climate change has affected populations of bumblebees (Bombus spp.) in Europe and North America (Soroye et al. 2020).

The title of the paper rather gives away its findings:  “Climate change contributes to widespread declines among bumble bees across continents“.  This study shows that, for the 66 species of Bombus studied, there had been a decline in species diversity in 100 km x 100 km quadrats of, on average, 46% in North America and 17% in Europe.  This loss of diversity has occurred in the period 2000–2014, relative to a baseline of 1901–1974.  Using some sophisticated analyses they show that climate change has been the main driver of these losses, and has been more important than factors such as changes in land use, pesticides, etc.  Which is not to discount those other contributors to pollinator loss: they can interact with climate change and are all part of the assault that we are imposing on the environment.

The most significant finding of the Soroye et al. (2020) study, and the reason why I’m discussing Erenler et al. (2020) in the same post, is that it’s extreme heat which seems to be the driving factor in determining Bombus declines.  Bumblebees are large, hairy insects because they are adapted to cooler conditions: they are not, by and large, tropical insects, except in mountainous areas.  Not surprisingly, then, it is the number of days of temperatures higher than those historically encountered by particular bee species that is the main driver of their loss from a region.  In relation to the figure above, this is the result of human-enhanced SHOCKs, and for heat-sensitive species like bumblebees, they are occurring more often than we had imagined when we wrote our review.  I fear that the coming years will see more examples of this as the effects of anthropogenic climate change continue to play out and our world experiences more extremes of weather events that are hotter, wetter, colder, drier, windier, and more combustible than we have previously known.

References

Biella P., Akter A., Ollerton J., Tarrant S., Janeček Š., Jersáková J. & Klecka J. (2019) Experimental loss of generalist plants reveals alterations in plant-pollinator interactions and a constrained flexibility of foraging. Scientific Reports 9: 1-13

Erenler, H.E., Gillman, M.P. & Ollerton, J. (2020) Impact of extreme events on pollinator assemblages.  Current Opinion in Insect Science (in press)

Soroye, P., Newbold, T. & Kerr, J. (2020) Climate change contributes to widespread declines among bumble bees across continents. Science 367: 685-688 [see also the commentary by Bridle and van Rensburg pp. 626-627 of the same issue]

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Filed under Australia, Bees, Biodiversity, Climate change

Neither left nor right, but international environmentalism: Australia reflections part 8

2020-01-13 12.17.33

The NASA Earth Observatory reported this week that “explosive fire activity” has caused smoke from the Australian bushfires to enter the stratosphere and be carried half way around the world.  That smoke is currently creating hazy skies and colourful sunrises and sunsets across South America.  In the coming months the smoke will complete a full circuit and arrive back in Australia, and then continue onwards … for who knows how long?

Nothing I’ve read this week sums up better the fact that the world’s environmental challenges, including climate change, are global in scale and scope.  They therefore require global initiatives to solve.  But as I’ll argue below, equating “green” politics with the left and “anti-environmental” policies with the right is an unhelpful characterisation.

Despite the need for global action, the world’s political landscape seems to be going in the opposite direction.  Inward-looking, right-wing populism is on the rise, and governments are hunkering down into a siege mentality of denying that there are any environmental problems that require serious, long-term action.  The Australian government, bolstered by the Murdoch-owned media empire (see Michael Mann’s recent piece on this in Newsweek), sees the bushfire crisis as “business as usual” even though all the evidence is to the contrary – demonstrated in this interesting piece from two Australian climate scientists.

Elsewhere in the world, Presidents Bolsonaro in Brazil and Trump in the USA are tearing up environmental regulations and “green tape” and allowing “the people” (or at least big business interests) to ransack the natural world for their own gain.  At the same time, one of the less-well-reported elements of Boris Johnson’s various speeches over the past few months has been its emphasis on the environment (he even used the word “biodiversity” in one of them) and the pressure he put on the other leaders of the G7 countries at their most recent meeting.  Perhaps that should come as no surprise given that Boris’s father, former Conservative MEP Stanley Johnson, has sound credentials as an environmentalist, particularly during his time with the European Commission. Indeed, in the mid 1980s Stanley Johnson received an award from Greenpeace for “Outstanding Services to the Environment”.  He’s even written for The Guardian, which is not the natural home for a member of the Conservative party.  There are other Conservatives with sincere pro-environmental attitudes (Zac Goldsmith and Rory Stewart come immediately to mind) and whatever you may think about their views on other topics, you can’t doubt their sincere environmental commitments.  And of course there are pro-environmental politicians in the Labour Party, and the Liberals and the SNP and Plaid Cymru and…..well, just about all of them.

Globally, both right- and left-governed states have variable environmental policies. Two countries recently reported that they had made extraordinary progress in tree planting restoration schemes: India (a right-wing, populist government) and Ethiopia (much more left-leaning).  China (communist in name but who knows what we should call it?) has a very mixed record on the environment, with huge investments in both solar power and coal mining.  It’s hard to get firm environmental data out of communist North Korea but the evidence so far suggests that they are not doing well: see this piece from 2009 by journalist Peter Hayes.

Closer to home, in the last few months on Twitter I’ve been called an “eco-loony” by a farmer; told that my objections to the High Speed 2 (HS2) rail infrastructure project were providing support for climate change deniers by a couple of train buffs; and accused of “sleeping with the enemy” by an environmental activist who didn’t like my stance on another large project.  The latter also tweeted a made-up quote from me to emphasise just how morally corrupt I was. Irony was lost on them I think.  I don’t know the political allegiances of those individuals but if I was a betting man I’d be fairly sure of a good return – definitely a mix across the spectrum.

Hopefully these examples make something abundantly clear: the relationship between politics and environmentalism is not straightforward.  That’s been obvious to me, and many others, for a long time.  But I’m not sure how widely understood this is because the impression that is presented to the public by both the right- and left-leaning media, is that “green equals left”.  And whilst there may be some truth to that currently in relation to the political alliances formed between various Green Parties, there is no historical basis for this correlation.  It’s even mixed up in the minds of the modern-day socialists. A few months ago a left-wing journalist opined that the left had “always” been pro-environmental, yet the (supposedly) socialist website Spiked has been publishing pieces arguing that environmentalists are against the working class and that de-carbonisation strategies will cost jobs – see this piece for instance.  Before anyone comments, I’m aware that Spiked has an odd and paradoxical history…..

Historically, both the far left and the far right have a mixed track record on the environment.  I read an appalling story recently about the Soviet Union whaling fleet killing whales simply to meet targets, not because they were of value economically; the author described it as “the most senseless environmental crime of the 20th century“.  However, communist Cuba set aside 10% of its area as national parks and biosphere reserves, and has a strong environmental track record.  In the 1950s, Maoist China had a policy of killing sparrows and other “pests” that was partly the cause of the Great Chinese Famine in which tens of millions of people died of starvation.  The first National Parks in the world were set up in the USA by what we could broadly consider conservative presidents, but the American legacy of nuclear testing and the fossil fuel industry is nothing to be proud of.  Finally, there is a long history of “green” fascism, from the environmental policies of the Nazis (I’ve not read this book but it looks fascinating), to individuals such as Jorian Jenks who was a founding member of the Soil Association, to modern day “eco-fascists” whose justification for carrying out mass-murder and domestic terrorism is rooted in arguments about reducing population growth in order to “save the Earth”.

It’s telling that Big Capitalism is starting to think more seriously about global environmental problems, how they can be solved, and at the same time create jobs and prosperity (and a buck or two for investors – I’m not naive).  Outgoing head of the Bank of England Mark Carney  has argued that firms and banks need to stop investing in fossil-fuels.  Many are following his lead, or are ahead of that curve, including the bank Goldman Sachs and the $7 trillion investment firm BlackRock which has recently stated that “climate change will become the centre of the firm’s investment strategy“.  Nobel Prize-winning economist Paul Krugman  has argued this week that Australia is showing us “the road to hell” and that governments and businesses of all political stripes and inclination better get on board with the environmental agenda.  Soon!

I firmly believe that neither the left nor the right are the friend nor the foe of environmentalism: there are plenty of historical and current examples of rapacious right-wing and left-wing governments, and also examples of such governments being highly pro-active at reducing  their country’s environmental impact.  The one thing that seems to me to be environmentally damaging is a rigid ideology that is followed through regardless of where it is positioned.

The title of this piece is a word play on a slogan adopted by the Socialist Workers Party: “Neither Washington nor Moscow but International Socialism”.  The environmental challenges facing our planet, our species, and the species with which we share this biosphere, are international in scope and it requires international, multi-partisan political action to address.   Whatever your personal political leanings, if you care about the planet, that statement must be blindingly obvious.  That’s why I’m so supportive of organisations like the UN’s IPBES (Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services).  Now, more than ever, the world needs this level of pan-national leadership.

If I’ve learned one thing as an ecologist it’s that the world is a complex, historically contingent and often unpredictable place: simplistic notions of socialism = good/bad and capitalism = good/bad are not going to solve the current crisis of climate change, loss of biodiversity, pollution, and a host of other environmental problems.  Only thinking outside of narrow ideologies is going to do that, and using the tools and strategies that are available to us, including market forces, open democracy, local activism, global movements, and whatever else works.  I’m still optimistic that the world can provide humanity with the kind of  metaphorical “pleasant walks” that Charles Darwin wrote about when he visited the Royal Botanic Gardens, Sydney:

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But we have to act fast.  Otherwise the ruins of civilization, and of the biosphere, may be our species’ legacy: that’s why I chose the image that opens this piece.

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Filed under Australia, Biodiversity, Charles Darwin, Climate change, IPBES

Just published: Interactions between birds and flowers of Rhododendron spp., and their implications for mountain communities in Nepal – download it for free

Figure 3

Back in April I posted a series of reports on a student field trip that I was involved with in Nepal, supporting our University of Northampton partner college NAMI in Kathmandu; the first one is here.  During that trip, my NAMI colleagues and I made some interesting observations about the role of generalist passerine birds and specialist flower-feeding sunbirds as pollinators of rhododendrons in the Himalayas.  This was subsequently followed up with another set of observations in which I didn’t take part, and then written up as a short research note.  I’m pleased to say that it has now been published in the new, open-access journal Plants, People, Planet.  Here’s a link to the paper which you can download for free:

Ollerton J., Koju N.P., Maharjan S.R. & Bashyal B. (2019) Interactions between birds and flowers of Rhododendron spp., and their implications for mountain communities in Nepal. Plants, People, Planet 00:1–6. https ://doi.org/10.1002/ppp3.10091

The report really asks more questions than it answers.  It points out how important these rhododendron forests are for the people of Nepal but that we know virtually nothing about the pollination biology of the dominant trees and therefore the long-term persistence of Rhododendron species in the face of forest exploitation and climate change.  Our hope is that it stimulates both further research on the topic and increased awareness of how important it is to protect these habitats.

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Filed under Biodiversity, Birds, Climate change, Pollination, University of Northampton

How are the Australian bushfires affecting biodiversity? Australia reflections part 4

2019-12-24 14.10.52

Australia’s vast, unprecedented wildfires are going to have a devastating effect on the biodiversity of the country.  To fully understand why this is the case, you need to know something about where species occur and why.

Australia is a land of lizards.  Karin and I see them everywhere we walk and frequently encounter them in gardens.  Reptiles are the most diverse group of vertebrates in Australia, with more than 1000 described species.  Of these, over half are lizards.  One family alone, the skinks (Scincidae) accounts for almost 440 species, with species new to science being described every year.  Some of these lizards are physically extremely impressive, particularly the dragons (Agamidae – about 90 species) and the monitors or goannas (Varanidae – 30 species).  We encountered lace monitors (Varanus varius) over Christmas at Port Macquarie, in coastal bushland and (very dry) rainforest at Sea Acres National Park (see photos above and below):

2019-12-26 10.06.02

Spot the goanna:

2019-12-24 11.10.25

Growing up to two metres in length, they seem to arrogantly swagger through the bush as though they own it; which of course they sort of do – they were here millions of years before people arrived.  Smaller but still impressive are the Eastern water dragons (Intellagama lesueurii) – here’s male and female checking one another out:

2019-12-24 11.23.26

Much smaller but more charming are the various skinks that seem to inhabit every garden and green space in the city; this one seems to be the Eastern water skink (Eulamprus quoyii):

2020-01-02 13.02.24

And here’s where we get to the main point of this post.  All of the lizards I mentioned above are endemic to Australia, it’s the only place on Earth where they naturally occur.  But they are all widespread species found across a huge area in the east of the country, from Queensland to Victoria, a linear distance of over 2,000 km.  This is unusual for species in Australia, and indeed in the rest of the world; most organisms naturally occur over a much smaller area.  To see what I mean, look at the image below from Steve Wilson & Gerry Swan’s book A Complete Guide to Reptiles of Australia:

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The maps adjacent to each species description illustrate the distribution of these organisms. The garden skink and the grass skink live in suitable habitat over vast areas. But the other two species are much more restricted in their ranges, which are so small that they need to be highlighted with arrows.  The elongate sunskink (Lampropholus elongata) for instance is found only “in the vicinity of Grundy Fire Tower and “The Flags”” at 1180-1455 m in the Great Dividing Range.  This is more typical of species distributions in Australia: most are restricted, and some are extremely restricted.  This is true of other reptiles, plants, birds, insects and fungi, in fact all major groups, not just the lizards.  Such a skewed distribution of species occurrences, with many rare and localised, and a few common and widespread, is natural; it’s an outcome of the processes of natural selection and evolution.  But it’s been exacerbated by habitat loss across the world, including Australia.  According to the Wilderness Society of Australia, the country “has lost 25% of rainforest, 45% of open forest, 32% of woodland forest and 30% of mallee forest in 200 years”.

But even these figures do not reflect the full scale of the loss: I’ve seen estimates that more than 90% of the temperate rainforest exemplified by Sea Acres National Park has been destroyed.  Given what I’ve said about the limited distribution of many species, that must mean that locally endemic species have gone extinct in the past.  The huge extent of some of the Australian bushfires, individually covering tens of thousands of hectares and collectively around 6 million hectares, means that most or all of a species’ population could be wiped out.  To give just one example, a small marsupial mammal, the Kangaroo Island dunnart (Sminthopsis aitkeni), is found only on Kangaroo Island.  Indeed, it’s restricted to the western part of the island, where a large bushfire has been raging out of control in recent days.  We will only know whether this species has survived, and in what numbers, once ecologists are able to survey the area once the danger is over.

However even for widespread species the fires can have a massive effect on their genetic diversity, which is an important component of biodiversity.  When we lose individuals from a population we lose genetic variants too.  A recent assessment by ecologists at the University of Sydney has suggested that almost half a billion reptiles, mammals and birds have been killed so far by the fires.  Losses of trees and other flowering plants, as well as insects, spiders and so forth, will be much, much greater of course.

This destruction of biodiversity has a human impact too.  On television news reports we’ve heard farmers and fire fighters describing the emotional trauma of seeing animals on fire and hearing the screams of koalas as they burn in the tree tops.  All of this biodiversity serves to ensure that Australian ecosystems function effectively and sustainably now and in the future. Ecosystems which are crucial for reducing the future effects of climate change, for ensuring supplies of fresh water, supporting agriculturally-important pollinators and predators of pests, and bringing in billions of tourist dollars.  All in all these fires are a tragedy for Australian biodiversity, as well as for the human population of this fabulous country.

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Filed under Australia, Biodiversity, Biogeography, Climate change, Mammals

A land of fire and water: Australia reflections part 3

Fire and water; those opposing elements have been our constant companions during this trip to Australia.  All the major international news media have been reporting on how serious the bush fire situation is in the south east of the continent.  In East Gippsland, Victoria, tens of thousands of residents and holiday makers have been advised to leave the area.  Four thousand of those who haven’t left were forced to spend last night on the beach, as fires got closer to the town of Mallacoota.  These are just the latest examples of climate change refugees in their own country, something I highlighted in a post about our visit to the USA earlier this year.  Of course, Australia is a continent that is used to bush fires, they are nothing new.  But what is new is the scale of these fires and the extended drought and high temperatures that are making the landscape more flammable than ever.

There’s currently a lot of media discussion in Australia about how landscapes were managed historically by Aboriginal peoples, whose selective and regular burning of the bush reduced fuel loads.  Karin and I have just returned from Port Macquarie where we enjoyed Christmas with an Australian branch of our family.  Several of them have spent a considerable amount of time working with remote Aboriginal communities in the Northern Territory.  We were told a story about an Aboriginal elder who asked one of our relatives to drive him out to an area of bush that had not been burned for over a decade.  It was that elder’s role to burn this land at regular intervals, a family tradition that went back generations.  Having driven for several hours along dirt roads, the elder asked to stop; he hopped out of the vehicle, went up to a patch of dry grass, and casually set fire to it with a small lighter he was carrying.  After pausing a few seconds to make sure that the flame had caught he hopped back into the car and said “Let’s get out of here”.  An hour back down the road the companions stopped and looked back.  The whole landscape was aflame, with a column of black smoke rising, I was told, in a mushroom cloud “like a nuclear explosion”.

This sounds extreme, but these areas are isolated and a long way from any human settlements or infrastructure.  Such activities have been part of toolbox of ways in which Aboriginal peoples have managed these landscapes for thousands of years.  By burning areas on a regular cycle the negative effects of large, out-of-control fires are reduced, and opportunities for seedling establishment and fresh foliage for animals to browse are created.  There’s more information about these practices here and here.

In the more heavily populated parts of Australia, and in the adjacent national parks, fires have long been suppressed, such that when they do occur they are much more violent conflagrations, over a greater area, than would normally be the case.

On one of our trips near Port Macquarie we came across an area of woodland that had burned recently, separated by a small road from an adjacent block that had not burned.  In the following set of images I’ve alternated the two blocks so you can see what the woodland looked like before and after burning.  But remember that this was not an especially intense fire; the trees are still living, and there is foliage in their crowns.  Once there’s been some rain and a chance for the vegetation to regrow, the previously burned block will look identical to the currently unburned area.  Indeed in one shot you can already see some green shoots emerging from the ground:

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So fire in itself is not a problem for these natural communities.  What is a problem, for nature and for the communities of people who live in and around these woodlands, is the intensity, the scale and the frequency of the fires that are currently occurring.  This morning Karin and I watched silently to a news report of yet another volunteer fire fighter who had lost his life overnight.  In this case he had been part of a crew whose 10 tonne fire truck had been lifted up and overturned by cyclone-strength winds created by the blaze itself – there’s a BBC news account of the tragedy here.  “Unprecedented” is a word we’re hearing a lot on ABC News.

Evidence for the number and size of the fires was everywhere in and around Port Macquarie, as we observed when we took a drive up to the peak of North Brother Mountain in Doorgan National Park.  From a height of about 470 m (1500 ft) we could see some amazing panoramic views of the region that also showed black fire scars on the landscape – this is looking south:

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Looking north there’s little evidence of the fires – some have occurred there but much smaller in scale.  But there is a lot of that second element, water.  We were able to explore some shallow coastal lagoons fringed with grey mangroves (Avicennia marina):

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Mangrove habitats are fascinating places that are ecologically important as nurseries for marine fish and invertebrates.  They also provide physical protection to coastlines, acting as a buffer to storm surges that would erode the land.  In recognition of this, a recent project around Port Macquarie has involved restoration of these mangrove areas and was instigated by commercial oyster farmers and a local fishing  society.  I’m particularly intrigued by the upward-pointing aerial roots of mangroves; termed pneumatophores, they function to provide oxygen to the trees, but also increase the physical complexity of the floor of the lagoon, providing habitats for small animals:

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But evidence of the drought in this part of the world is never far away.  On our seven-hour train trip back to Sydney we passed mile after mile of parched farmland, with dried-up waterholes and dust-filled streams.  The only thing stopping it from burning is the absence of vegetation:

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As I complete this blog post, it’s 31st December and we’re back in Coogee Bay, ensconced in the apartment of my colleagues Angela and Stephen.  They have headed to Stephen’s native Canada to visit family.  It’s going to be cold!  We’re very happy to house sit and see in the New Year in warmer climes.  Best wishes for 2020 to all of my readers: let’s hope that it’s the start of an environmentally more enlightened decade.

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Filed under Australia, Biodiversity, Climate change, Ecosystem services