Could a podcast stop mosquito bites?

podcasting_mozziebites

This week I’m attending OzPod 2016: the Australian Podcast Conference, a workshop at the ABC, Ultimo. Celebrating International Podcast Day, the workshop brings together podcasters for “an event for the expanding podcast industry to escape the studio or office and meet with peers to share experiences, information, insights and ideas around audience acquisition and retention, new technologies, the rise of the podcast in traditional media, monetizing and of course the fine art of storytelling.”

 So, why am I going? I don’t even have a podcast!

I may not have a podcast now but I hope to start playing around with the platform soon as a complement to my other efforts to spread the word on science communication and public health awareness.

I’ve been thinking about kicking off a podcast for a while but have been a little reluctant due to time commitments. More importantly, I’ve also wanted to have a clear idea of what exactly I want to do.

In a previous life, I co-hosted a radio show on FBI Radio (during their test broadcast days) with my wife called “Good Morning Gidget”. It was a Saturday morning show of surf music and interviews with professionals involved in a wide range of coastal-based activities, from marine biologists to surf shop owners. Despite the early start on a Saturday morning, it was a load of fun. I’d also worked behind the scenes producing a couple of music shows. If I had more time, I really would have liked to pursue more work with community radio.

Perhaps podcasting will be the backup plan.

flashforward_swatting

It’s great to listen back to packaged interviews with radio, like the Health Report (I’m talking zika virus) but I was also lucky enough to have a chance to contribute to a few podcasts this year. I spoke with Science On Top about the outbreak of Zika virus and the implications it has for Australia, Flash Forward on what will happen if we eradicate mosquitoes from the planet and ArthroPod on what its like to study mosquitoes for a living!

All these were a lot of fun and were really motivating for me to want to get started with podcasting myself.

I feel like my experience with sound recording and ongoing engagement with media provides a solid background in most of the technical skills I need to get started. I’m hoping I’ll leave the OzPod 2016 conference with a few more tips on story telling and structuring a podcast too.

What I’ve been struggling with is format. I like the conversational nature of most podcasts but as I’ll probably be doing everything myself, perhaps a more structured and edited podcast is the go?

There are very few podcasts I listen to that are built around a one-person show. I’m not sure I could pull it off. Does anyone really want to listen to me ramble on for 20 mins about mosquitoes? 40minutes?

Sometime over the coming summer I hope to launch a short series of podcasts covering some of the basics of mosquito biology and how that relates to the ways we protect ourselves and our families from mosquito bites and mosquito-borne disease. I want to share my fascination with mosquitoes and explore some of the gaps in our understanding of mosquitoes, particularly their role in our local environment. 

Hopefully I can recruit some of my colleagues from around Australia for a chat too so we can share a little about the science behind our public health messages and what life is like to be chasing mosquitoes around swamps all summer

Sound like a good idea? Join the conversation on Twitter and let me know what you think, would you listen to a podcast about Australian mosquitoes?

 

 

 

 

 

 

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Social media and blood suckers showcased at the International Congress of Entomology

instagram_wetlands_webb

Digital technology is changing a lot about how we undertake entomological research and communicate the results of that research to the community and policy makers.

This week in Orlando, Florida, is the International Congress of Entomology (ICE). A huge gathering of entomologists from around the world. While it was a great pleasure to be invited to participate, I couldn’t get over there this time.

I will, however, have a chance to present my work in the Symposium “Entomology in the Digital Age”  Friday, September 30, 2016 (01:30 PM – 04:45 PM), Convention Centre Room W222 A.

In the presentation I’ll share some of the reasoning behind my use of social media to engage the community with both entomological research and public health communication. Most importantly, it will focus on some of the metrics I’ve recorded alongside my use of social media, maintaining a blog of research and writing for outlets such as The Conversation.

I’ve written about my use of social media and how it can help extend the reach of public health messages and presented on the topic alongside a range of great speakers at the 2014 Entomological Society of America meeting in Portland.

This time around, technology is playing an even more direct role in my presentation! I’ve pre-recorded my presentation and it will be shown to the audience on the day among other presentations. I’ll also be checking into the session to answer questions. Despite the fact I’ll need to be up around 1:30am due to time differences, it should be fun.

See the abstract below…

Taking entomological research from the swamps to the suburbs with social media

Cameron E Webb

Connecting scientists and the community is critical. This is particularly the case for medical entomologists working in the field of mosquito-borne disease where the translation of entomological research into improved public health outcomes is a priority. While traditional media has been the mainstay of public health communications by local authorities, social media provides new avenues for disseminating information and engaging with the wider community. This presentation will share some insights into how the use of social media has connected new and old communications strategies to not only extend the reach of public health messages but also provide an opportunity to promote entomological research and wetland conservation. A range of social media platforms, including Twitter, Instagram, and WordPress, were employed to disseminate public health messages and engage the community and traditional media outlets. Engagement with the accounts of traditional media (e.g. radio, print, television, online) was found to be the main route to increased exposure and, subsequently, to increased access of public health information online. With the increasing accessibility of the community to online resources via smartphones, researchers and public health advocates must develop strategies to effectively use social media. Many people now turn to social media as a source of news and information and those in the field of public health, as well as entomological research more generally, must take advantage of these new opportunities. doi: 10.1603/ICE.2016.94611


If you’re at ICE, you can also catch up with my PhD student David Lilly who’ll be presenting our research into the development of insecticide resistance in bed bugs as part of the symposium “New Insights into Biology, Resistance Mechanisms, and the Management of the Modern Bed Bug” Friday, September 30, 2016, 01:30 PM – 04:45 PM, Convention Center, West Hall F4 (WF4).

Novel insecticide resistant mechanisms in the common bed bug, Cimex lectularius

David Lilly, Cameron E Webb and Stephen Doggett

Introduction: Research on field strains of Cimex lectularius from Australia has identified widespread resistance to pyrethroid insecticides, but variability in the magnitude expressed. To determine if differences in resistance mechanisms exist, collected strains were examined for the presence of metabolic detoxification and/or cuticle thickening. Methods: The presence and relative contribution of detoxifying esterases or cytochrome P450 monooxygenases were assessed. Bed bugs collected from Parramatta (NSW), Melbourne (VIC) – 2 strains, ‘No.2’ and ‘No.4’, and Alice Springs (NT) were exposed in topical bioassays employing deltamethrin and two pyrethroid synergists: piperonyl butoxide (PBO) and EN16/5-1. PBO inhibits both monooxygenases and esterases, whereas EN16/5-1 will inhibit esterases only. Thus in a comparative bioassay, the results can infer the dominant enzyme system. The Parramatta strain was then selected to study the potential presence of cuticle thickening. Nine-day-old male bed bugs were exposed to filter papers treated with the highest label rate of Demand Insecticide®(200mL/10L of 25g/L lambda-cyhalothrin) and were grouped according to time-to-knockdown (< 2 hours, ≥ 4 hours, and survivors at 24 hours). Measurements of mean cuticle thickness at the transverse midpoint of the second leg tarsus were taken under electron microscope. Results/Conclusion: All strains possessed resistance that was inhibited by the synergists, with the Parramatta and Melbourne No.2 indicating esterase-dominance, and Alice Springs and Melbourne No.4 indicating cytochrome P450 monooxygenase-dominance. Cuticular measurements demonstrated that bed bugs surviving deltamethrin exposure had significantly thicker cuticles, denoting a novel form of resistance in these insects. doi: 10.1603/ICE.2016.92553

 

You can also see Stephen Doggett (co-author and photographer of A Guide to Mosquitoes of Australia) speaking on photographing mosquitoes to in the symposium “Insect Photography Symposium: Bringing the Small to the World.


You can join the conversation on Twitter and keep an eye on all the fun in Orlando by keeping an eye on the tweet stream!

 

Taking Australian wetland research to China

jayne_mosquitotrap

My PhD student Jayne Hanford has been super busy this year. Not much more than a year into her candidature and she has already locked away a summer of research and has been presenting her findings at conferences here in Australia as well as overseas.

After recently sharing our research at the Society for Wetland Scientists Annual Conference held in Corpus Christi, Texas, USA and the Mosquito Control Association of Australia conference on the Gold Coast, Jayne is off to China for the 10th INTECOL International Wetlands Conference.

Her research is focused on understanding the links between wetland vegetation, aquatic biodiversity and mosquito populations. Better understanding of these links will assist management strategies that minimise actual and potential pest and public health risks associated with mosquitoes and urban wetlands.

Our abstract for the conference is below:

Is the Biodiversity Value of Constructed Wetlands Linked to their Potential Mosquito-Related Public Health Risks?

Jayne Hanford1, Cameron Webb2, Dieter Hochuli1

1School of Life and Environmental Sciences, The University of Sydney, Australia; 2Department of Medical Entomology, Westmead Hospital and The University of Sydney, Westmead, Australia

 Stormwater treatment wetlands constructed in cities can enhance the sustainability of urban biodiversity by providing wildlife refuge areas and habitat connectivity. However, the creation of wetlands for stormwater infrastructure can increase risks to public health and wellbeing by proliferating nuisance-biting and pathogen-transmitting mosquitoes. In severe cases, this proliferation can erode goodwill in the community for creating and protecting valuable wetland systems.  We compared mosquito assemblages at 24 natural and constructed urban wetlands in the greater Sydney region, Australia. Our aim was to determine if stormwater wetlands constructed with the goal to support high biodiversity value also had reduced associated mosquito risks. Wetlands were located across a gradient of urbanisation determined by surrounding human population density, and included sites with different aquatic and riparian habitat complexity and availability. Adult and larval mosquitoes and aquatic macroinvertebrates were sampled on two occasions through summer and autumn. Aquatic macroinvertebrates were used to derive health indices, as well as being a relative measure of aquatic diversity.  Diversity of adult mosquito species was high, and abundance varied greatly between wetlands. Macroinvertebrate assemblages were also highly variable between sites. Wetlands with greater habitat complexity had lower adult mosquito abundance and greater mosquito species diversity, compared to stormwater-specific wetlands with minimal available habitat. As expected, mosquito assemblages did not respond to urbanisation and aquatic macroinvertebrate assemblages per se, but appeared to respond to a complex suite of coarse and fine-scale features that may affect a wetland’s biodiversity value.  Effectively integrating wetlands into cities requires balancing their design for water infrastructure purposes, biodiversity resources and public health and wellbeing requirements. Understanding the risks as well as the benefits will enhance the value of constructed urban wetlands in sustainable cities while minimising public health risks posed by mosquitoes.

Jayne will be speaking in the “The next generation of wetland science: ecosystems, applications, and engineering” session in the Nanhu Room 1520-1530 on Wednesday 21 September.

You can keep an eye on whats happening in China by following Jayne on Twitter and checking the hashtag

westernsydneywetlands

The Society for Wetland Scientists Annual Conference held in Corpus Christi, Texas, USA back in May included a paper by Jayne titled “Risky Wetlands? Conflicts between biodiversity value and public health” and prompted some great feedback and discussion among wetland scientists at the meeting. It was a successful trip and a timely reminder that I must get to one of the SWS meetings sometime soon, perhaps Puerto Rico?

Keep an eye out for Jayne’s research publications soon!

 

 

 

Around the world in a thousand fleas

fleas

The International Congress for Tropical Medicine and Malaria (ICTMM) kicks off in Brisbane, QLD, Australia this week running from 18 through 22 September. This is a big conference and wonderful for local researchers to be showcased to an audience of international scientists from our own backyard in QLD.

I couldn’t make this meeting unfortunately but luckily my wonderful PhD student Andrea Lawrence will be presenting some of our flea research as part of the Australian Society of Parasitology conference that is incorporated into ICTMM this time around.

Andrea has been doing some excellent research during her candidature and you can read some of it here [Evaluation of the bacterial microbiome of two flea species using different DNA isolation techniques provides insights into flea host ecology] and here [Integrated morphological and molecular identification of cat fleas (Ctenocephalides felis) and dog fleas (Ctenocephalides canis) vectoring Rickettsia felis in central Europe].

This week she will be sharing her research into the genetics of global cat flea populations. You can catch Andrea on Tuesday 20 September in the Zoonoses session in M4, 13:00-15:00.

Our abstract is below:

One thousand fleas from fifty countries: global genetic structure and morphometrics of the common cat flea (genus Ctenocephalides) reveals phylogeographic patterns and resolves the generic complex.

Andrea Lawrence, Cameron E. Webb and Jan Šlapeta

School of Life and Environmental Sciences (SoLES), Faculty of Veterinary Science, The University of Sydney, Australia and Department of Medical Entomology, The University of Sydney and Pathology West, ICPMR, Westmead, Australia

The common cat flea and its relatives (genus Ctenocephalides) are considered the most successful ectoparasites on earth. The widespread parasitisation of these insects on mammals closely associated with humans (e.g. dogs and cats) represents significant potential for vector borne disease transmission. Fleas of the genus Ctenocephalides represent a unique model to study the effects of modern human migration and geographic and climatic barriers on parasite diversity and diversification. We have amassed a world-wide collection of Ctenocephalides over a period of 7 years, and analysed over 1000 flea samples from ca. 50 countries representing all continents bar Antarctica. Novel integration of morphology, morphometrics and molecular identification and phylogenetics using a combination of four mitochondrial and nuclear DNA markers, reveals phylogeographic patterns and evolutionary relationships of global cat flea populations. These techniques provide resolution of the long disputed Ctenocephalides generic complex, which has not yet been definitively resolved despite its significance in veterinary and public health. Understanding of contemporary population structure inferred from global phylogeographic analysis has implications for parasite and flea-borne disease management. It is hoped that this work will form the authoritative estimation of the origin of the genus Ctenocephalides and the subsequent species evolution and migratory radiation.

Keep an eye on the official conference hashtag [#ICTMM2016] and why not follow Andrea on Twitter for more!

The lead image on this article is modified from Andrea’s paper, “High phylogenetic diversity of the cat flea (Ctenocephalides felis) at two mitochondrial DNA markers

 

 

 

 

 

Can social media help translate research to practice and promote informed public health messages?

I’m a Senior Investigator with the Centre for Infectious Diseases and Microbiology – Public Health. One of our primary focuses is translating research into improved public health outcomes. With NSW Population Health and Health Services Research Support Program assisting our work, we’re exploring new ways to achieve this objective. My experience of using social media was selected to be showcased among other case studies in 2015. 


Nuisance-biting mosquitoes and mosquito-borne disease are concerns for local authorities in Australia. 2015 saw the largest outbreak of mosquito-borne Ross River virus disease for more than 20 years with over 9,500 cases nationwide. In NSW, there were 1,633 cases compared to the annual average since 1993 of 742 cases per year. Notwithstanding the current outbreak, other endemic, as well as exotic, mosquito-borne pathogens represent future threats to public health.

As there is no large-scale mosquito control program in NSW, reducing the contact between mosquitoes and people is primarily achieved through the promotion of personal protection measures. NSW Health promotes the use of topical insect repellents in combination with behavioural change to avoid natural mosquito habitats and the creation of mosquito habitats around the home. This information is typically provided in the form of posters, brochures, online factsheets, and seasonal or outbreak-triggered public health messages issued by Local Health Districts or the NSW Ministry of Health.

With the emergence of new communications technologies, particularly the rise in popularity of social media, there are new opportunities for public health communications.

The aim of the current research was to determine the reach of public health messages through social media by tracking engagement, audience and relative value as assessed by media monitoring organisations and metrics provided by hosting services of social media platforms.

Assessing activities and processes

Dr Cameron Webb (CIDM-PH) has focused much attention on filling the gaps between current public health messages and findings from recent research into topical mosquito repellents.[1] For example, while public health messages provide accurate information on the insect repellents that provide the best protection, there is a paucity of information provided on how best these products should be used by individuals and those they care for.

Dr Webb’s engagement with mass media, online media (e.g. The Conversation), a personal blog (e.g. Mosquito Research and Management) and social media (e.g. Twitter) has resulted in substantial exposure of focused and informed public health messages. From mid-2014 through to the end of 2015, Dr Webb participated in over 80 mass media articles and interviews in print, online, radio and television media with public health information reaching an estimated audience of over 10 million people.[2] The focus of his messaging around mosquito-borne disease was to highlight the best way for the community to choose and use mosquito repellents; stressing the importance of active ingredients and application methods. This fills a gap in the current provision of public health information while also augmenting public health alerts and messages associated with the 2015 outbreak of Ross River virus disease.

Social media has become a “go to” source of information for much of the community. Information shared on Facebook, Twitter, Instagram, and YouTube has the potential to shape the habitats and behaviour of the community. Dr Webb is active on Twitter (currently followed by over 4,500 people); he uses the platform to engage with the social media accounts of journalists and broadcasters to establish a voice of authority in the field of mosquito-borne disease prevention and extend the reach and exposure of public health messages broadcast through mass media. Using Twitter to share links to informed articles following interviews reached hundreds of thousands of people by being shared by the social media accounts of journalists, media outlets, government organisations and community groups. During the 2014-2015 summer, tweets by Dr Webb reached an estimate 1.28 million people.[3]

Dr Webb regularly writes open access articles on his website, attracting around 250 daily visitors with over 117,000 article views.[4] In addition to his personal website, Dr Webb regularly contributes articles to The Conversation (a website for academics to share expert opinion and write about their latest research). His articles have attracted over 120,000 readers. However, one article “why mosquitoes seem to bite some people more” (published 26 January 2015) has alone been read by over 1.3 million people.[5] This “non-scholarly” writing not only establishes CIDM-PH scientists as authorities in public health matters but can also assist in directing the public to official health guidance provided on official websites and other sources.

Dr Webb’s activities provide a framework for how health authorities may engage with social media to extend public health messages. Organisations or individuals can connect health authority information with the community through media outlets. He has been invited to share his experiences in this field at local and international conferences and workshops including those coordinated by the Public Health Association of Australia, Australian Entomological Society and Entomological Society of America. In addition, Dr Webb has been invited to provide lectures on the benefits of social media for public health advocacy to undergraduate and post-graduate students at the University of Sydney.

While traditional messaging provided by health authorities will remain a staple in public health campaigns, social media provides a connection between traditional and emerging media and communication organisations. This increased connectivity between public health advocates, the media and community has the potential to greatly improve the awareness of mosquito-borne disease and increase the rate of uptake and application of strategic personal protection measures.

References

  1. Webb C.E. (2015). Are we doing enough to promote the effective use of mosquito repellents? Medical Journal of Australia, 202(3): 128-129.
  2. Estimated audience reported by Kobi Print, Media and Public Relations, University of Sydney, 23 April 2015, based on data provided by media monitoring organisation isentia.
  3. Estimated from total “tweet impressions” for the period October 2014 through April 2015 provided by Twitter Analytics (https://analytics.twitter.com/user/Mozziebites/home accessed 30 April 2015)
  4. Data provided by WordPress statistics (accessed 18 December 2015)
  5. Data provided by The Conversation metrics (accessed 18 December 2015)

This article was originally published by NSW Health showcasing some of the work within the NSW Population Health and Health Services Research Support Program. You can see the original article here.

Should we start pulling out mangroves to save our wetlands?

mangroves_webb_SOPA_November2015

You have no idea how badly I wanted to jump down into the thick black mud.

I don’t remember much about primary school but I do have strong recollections of an assignment on the importance of mangroves to the ecology of the Parramatta River. Perhaps not the assignment itself, but I do remember Mum and Dad taking me down to the river and I drew some pictures of the twists and turns of branches and trunks and the finger-like pneumatophores punching up through the thick dark grey mud. It may only have been 10 minutes drive from home in Western Sydney but it was a glimpse into a world so strange and alluring, how could it not have made an impact on me?

I remember the great disappointment of my parent’s stern words keeping me from jumping down below the high water mark and into the mud. The same feelings of frustration and disappointment when stopped from doing other fun things like playing in stormwater drains, letting off firecrackers or swimming in rips!

Mangroves don’t just attract the attention of young environmental scientists. Exploiting a unique place between the land and sea, mangroves have intrigued and fascinated many before me with the first descriptions, by Greek mariners, thought to date back to 325BC. What were these plants that seemed to defy logic, growing half submerged in salty water?

Almost thirty years after my primary school assignment, with sandshoes replaced by gumboots, that childhood disappointment of adventure squashed is now matched by the realisation that mangroves aren’t perfect. In fact, they’re a threat to some of the other plants and animals found in our local local estuaries.

Now I spend most of my summer coated in that same dark grey mud, covered in mosquito bites and thinking about how important mangrove management will be for the future of our coastal wetlands.

mangroves_duckcreek

More than mangroves

There is little doubt mangroves are an ecologically important habitat. They provide a home for a wide range of creatures, from bacteria to birds. Rich in nutrients and hiding places, mangroves are perfect nurseries for fish and crustaceans. Bird and bats and rodents and reptiles all find a home here too.

They’re threatened by climate change but they may also play a critical role in protecting our shoreline against sea level rise and storm surges. Sea level rise itself may knock out mangrove forests too but mangroves could also mitigate the impacts of climate change by storing carbon. In fact, the role estuarine wetlands may play in keeping carbon dioxide out of the atmosphere could be critical.

Make no mistake, mangroves are important. Thing is, it is also important to also remember that estuarine wetlands are more than just mangroves.

When we talk about estuarine wetlands, we’re grouping together a number of habitats that  include seagrass, saltmarsh, sedgelands and mudflats as well as mangroves. Each of these habitats play an important role in the functioning of the estuary as a whole but they each, individually, provide something specific to the wildlife that utilise the wetlands.

darkmangroves

Saltmarshes are critically important and are in desperate need of conservation. In NSW they’re listed as Endangered Ecological Communities. As well as urbanisation and pollution, a changing climate and sea level rise risk severely degrading the quality of these habitats.

One of the key threats facing saltmarshes is a native plant. A native estuarine wetland plant. Mangroves.

The encroachment of mangroves into saltmashes is a serious problem. This is happening in many parts of the world. It is a strange situation in which one native plant is taking over another and with these ecological shifts, there are knock-on effects to other components of the wetland ecosystem. Most importantly, nesting and feeding shorebirds.

saltmarsh_SOPA

Are mangroves really a threat?

The mangroves are just doing what mangroves do. The reason they’re threatening saltmarshes is due to our modification of local environments.

Urban runoff reduces the salinity of these wetlands and this reduced salinity not only removes the ecological advantages of salt-tolerent saltmarsh plants, such as Sarcocornia quinqueflora and Sporobolus virginicus, but it helps mangrove seeds and seedlings survive the otherwise harsh environmental conditions of saltmarshes. Lower the salinity, increase the invasive potential of mangroves.

Frequent dryness and highly salty conditions are a saltmarsh’s best defense against invading mangroves.

Filling in wetlands and the construction of seawalls, roadways and other infrastructure give saltmarshes little refuge or respite from these threats. While mangroves encroach from the sea, there is nowhere for saltmarshes to migrate to when dealing with sea level rise.

They’re cornered and under attack but even where the plants are persisting, the quality of habitat they provide for local wildlife is slowly degraded by colonising mangrove seedlings.

Blackwingedstilt_henandchickenbay_1september2015

There are many waterbirds that use our local estuaries that are under threat. Saltmarshes are great habitats for migratory shorebirds. There are plentiful resources in the form of insects and other invertebrates within the sediments. The birds can nest on the marsh and as they can see all around, predators are easy to spot. They feel safe.

There have been declines in the White-fronted Chat populations around Sydney. Many other populations of wading birds associated with Australia’s coastal wetlands are in decline too. Mangrove invasion isn’t the only thing to blame but it is an issue that needs to be addressed.

For many of these birds, the encroachment of mangroves into mudflats and saltmarshes is a problem. Its a problem for their foraging and nesting. Once mangrove seedlings start popping up on the middle of the saltmarsh, all those advantages of a wide open habitat in which predators are easy to spot are lost.

Imagine you’re a black-winged stilt. You’re trying to find a safe place to nest. A perfect place would be a raised area of saltmarsh surrounded by water. A dead flat saltmarsh with clear lines of sight for dozens of meters around. You’ll be able to see an approaching predator (like a fox or a feral cat) from far enough way to escape with plenty of time to spare. Now, stick a few mangrove seedlings here and there. They start to obscure your view. They’ll give sneaky predators a place to hide. Even if there are not predators about, you’ll probably get nervous. You’ll probably spend more time thinking about the threat of predators and less time foraging for food.

As mangroves move in, the birds will leave. Long before the saltmarsh is over run by mangroves, out-competed by the shade of establishing young mangroves, the quality of the habitat for many shorebirds will have already been lost. There may be some plants remaining but the ecological role of the habitat is gone.

Parramatta_ConradMartens

Do historic paintings provide conflicting evidence to the commonly held view that mangroves have always been present along the Parramatta River? (Parramatta River, c. 1837, Conrad Martens (1801-78) via Australian Art Auctions)

Painting the picture of change in the local wetlands

How can we predict what will happen in the future if we haven’t learned from the past?

Tracking change in these wetlands is important. The use of photography has played an important role in tracking environmental change for a long time. Aerial photography and satellite imagery have helped reveal dramatic changes in vegetation associated with Australia’s coastal wetlands. This analysis has demonstrated the encroachment of mangroves into saltmarshes and this encroachment is considered a key threatening process of this endangered ecological community.

How can we track the encroachment of mangroves? While technology has helped reveal current changes in mangrove encroachment, other uses of imagery can explore relatively recent “urban myths” about historic mangrove distribution.

Thinking back to that school assignment, I remember being told how important mangroves were to the local environment. We we taught that, here in Sydney, that mangroves were always part of the Parramatta River estuary, that they have alwasy been a critical component of the river’s ecology. Was this really the case?

There has been some brilliant detective work done to determine the historic distribution of mangroves along the Parramatta River in this paper titled “Estuarine wetlands distribution along the Parramatta River, Sydney, 1788–1940: implications for planning and conservation“. The authors have used old photos and, in particular, some of the earliest paintings from the Sydney region (together with notes from settlers at the time) and found that the estuary was dominated by mudflats and saltmarsh habitats and that extensive areas of mangroves did not occur until the 20th Century.

To quote the author, Lynette C. McLoughlin:

“These historical sources indicate that in the 19th century extensive mudflats and saltmarsh communities dominated the inter-tidal zone, with mangroves more limited to creek fringes and some patches in bays for much of the period. In the upper river from Subiaco Creek to Parramatta, there is no evidence for the presence of mangroves until the 1870s. Following settlement and increased sedimentation, inter-tidal mudflats expanded, mangroves colonised up river and out onto mudflats in bays in the latter part of the 19th century, followed by expansion into saltmarsh in the 20th century.”

It is only relatively recently that mangroves have really flourished along the river.

There is absolutely no doubt they were always present, tucked away in the tiny bays and inlets of what became known as Sydney Harbour but it was the mudflats and saltmarshes that dominated much of the estuary. These habitats, no doubt, provided a rich and productive habitat for shorebirds and other wildlife.

mangroves_Dec2015_HenandChickenBay

So, where to from here?

Globally, mangroves are a critical component of wetland ecosystems. There is little doubt of that, and little doubt that in many parts of the world, even here in Australia, they are under threat. But so is saltmarsh and, saltmarsh is far less likely to be given the chance to demonstrate the resilience that mangroves will to continued changed environmental conditions results from a rising sea level and surging urbanisation.

Not just saltmarsh but mudlfats too.

Coastal authorities are increasingly aware of the need to balance protection of mangrove forests and the benefits they provide but also the conservation of saltmarsh and mudflats that are so critical to shorebirds.

The reality is, there will need to be a program of mangrove culling to sustain conservation of saltmarsh habitat. You need a permit to remove mangrove seedlings but a seasonal program of removal would be greatly beneficial in stopped the spread of mangroves into saltmarsh habitats. Local authorities are incorporating mangrove removal programs in their local wetland rehabilitation programs.

Removing young seedlings is easy, you can pull them straight out of the wet mud. Wouldn’t take much to organise a team of volunteers to move through the local saltmarsh removing seedlings. Perhaps in Autumn when the migratory shorebirds have left and the mosquito populations aren’t so bad?

The idea that native vegetation should be actively removed from habitats sounds at odds with environmental conservation. However, we need to maintain our wetlands for our future generations and the next generations of birds, and fish and crustaceans that rely on them now where few other opportunities exist.

mangrove_boardwalk_Jan2016

2 February is World Wetlands Day. Please get out into your local wetlands, or at least make a pledge to visit your nearby wetlands sometime soon.

Learn more about Australia’s amazing mangroves by dropping by MangroveWatch and picking up the excellent Australia’s Mangroves by Norm Duke. There is also an extremely useful text on Australian Saltmarshes that is essential.

Finally, check out one of the most extensive resources on urban wetland management, including estuarine wetlands, via the free eBook produced by the Sydney Olympic Park Authority titled “Workbook for Managing Urban Wetlands in Australia“. Read a brief article on our analysis of the use of this resource in the latest issue of Wetlands Australia, see “Insights from the use of an online wetland management resource” by Webb and Paul (pages 26-27).

What are you doing for World Wetlands Day? Join the conversation on Twitter!

Want to learn more about the amazing world of Australian mosquitoes? Check out “A Field Guide to Mosquitoes of Australia” out now through CSIRO Publishing. Over 200 pages containing a pictorial guide to almost 100 different mosquitoes along with tips on beating their bite and protecting your family from the health risks of mosquitoes. You can order online or through your favourite local bookstore or online retailer.

 

How to beat the bite of backyard mosquitoes

dude_sandpit_30032014Summer is here and you’ll want to know how to spend time in the backyard without a barrage of bites from pesky mosquitoes!

There is little doubt mosquitoes are a nuisance but in some parts of Australia but they can also pose a health risk. Around 5,000 people a year are infected with Ross River virus. In fact, 2015 saw the biggest outbreak of mosquito-borne Ross River virus disease ever recorded in Australia.

I recently shared ten tips on keeping free of mosquito bites with the University of Sydney that proved popular so now here are five top tips (with a bit more detail) to help reduce the risk of mosquito bites and get the most out of your backyard this summer!

Water water everywhere, just what mozzies love

Don’t let mosquitoes find a home around your home.

The immature stages of mosquitoes (commonly known as wrigglers) are found in free-standing water so drain, tip out or cover any water holding containers. These can range from buckets and discarded tyres to children’s toys and slumped tarpaulins covering boats or trailers.

Flush out your bird baths with a hose once a week (you can also scrub it with wire brush to dislodge any mosquito eggs). Mosquitoes can even find a home in your pet’s water bowl so empty before refilling at least once a week.

Can you see a puddle or pool of water? There are probably mosquitoes in there, or dozens of eggs waiting to hatch.

Pot plant saucers (particularly “self watering” pots) are great places for mosquitoes. If you fill saucers with sand, the moisture will be trapped but there won’t be any “free standing” water for mosquitoes to use. Good for the plants, bad for mosquitoes.

Sometimes the problem comes from above. Check your roof gutters, when they get blocked with leaves and water is trapped it provides habitat for mosquitoes. Same goes for courtyard drains, make sure you clean out soil, sand and other debris that might trap pools of water.

Make sure you keep your swimming pool chlorinated. Neglected swimming pools can harbour mosquitoes, especially mostly empty in-ground pools that partially fill following rainfall.

Webb_bucketsofrainwater

It may seem like a good idea to store water around the home to help keep plants going during a long hot summer but any water, from a full rainwater tank to a few drops in the base of a pot plant saucer, can make a great home for mosquitoes!

Spray with care (if you really need to)

A range of products is available that will help control mosquitoes. It is important to ensure that any product used is registered with the Australian Pesticides and Veterinary Medicines Authority (APVMA). The APVMA test products for their effectiveness and safety and it is critical that the instructions on the insecticide label are followed.

The insect growth regulator methoprene (NoMoz) and the monomolecular film (Aquatain) can both be used to stop mosquitoes emerging from backyard habitats. A few pellets of methoprene or a few drops of monomolecular film into water can be enough to provide a month or so of mosquito control. It was once common practice to put a teaspoon of kerosene into rainwater tanks (the kerosene floats on the surface of the water, drowning mosquito wrigglers), now monomolecular films can be used. Keep in mind though, if your rainwater tank is properly screened, you don’t need to worry about putting anything inside.

For mosquitoes flying in from beyond the backyard, sometimes you need to use insecticides. Insecticide sprays generally fall into one of two categories. “Knockdown” sprays are designed to kill flying insects while they’re buzzing about. While they’ll certainly kill mosquitoes, mosquitoes are far less likely to be randomly flying about in the backyard. They’re usually a little more sneaky than that. A better option will be “surface sprays” that provide some residual control and kill the mozzies where they hide out.

Residual insecticides (typically containing synthetic pyrethroids and often marketed as “surface sprays”) can be applied to cool and shaded areas. The most effective places will be under outdoor furniture, the shaded sides of buildings, verandas or within vegetation. While these products are safe for people and pets, they are likely to impact non-target insects too (e.g. bees, butterflies, beetles) so should be employed judiciously, especially if spraying on plants. Never spray them into or around ponds as these insecticides can be toxic to fish. Always check the label of the insecticide for directions.

I once asked a local resident if this type of spraying worked in reducing mosquito numbers around the home. “Yeah, it killed everything” they replied. We really don’t want to be killing everything so please be careful when using these products.

vintage_bugspray_

Vintage insecticide advertising (Source: Envisioning the American Dream)

Topical mosquito repellents will remain the first line of defence for many when mosquitoes are out in force. Products that contain DEET (diethyltoluamide) or picaridin will provide the longest lasting protection but make sure they’re applied correctly. You’ll need a thin coverage of all exposed skin. A dab “here and there” won’t be enough. Plant-based products (e.g. tee tree oil) will provide some protection but will generally need to be applied more frequently than the other repellents to ensure long lasting mosquito bite protection.

Burning coils and switching on zappers

The smell of mosquito coils is up there with the smell of sunscreen and BBQs as a reminder of summer. Mosquito coils and sticks are good at reducing the number of mosquito bites but they’re unlikely to stop them all. A recent study found little evidence that burning mosquito coils prevents malaria so don’t expect all biting mosquitoes to stop once you light up a coil. Make sure you use coils or sticks that contain insecticide (e.g. pyrethroid) and not just botanical extracts (e.g. citronella) as the insecticides will actually kill some mosquitoes.

Never sleep in an enclosed room with a mosquito coil burning. Seriously, don’t keep a mosquito coil burning overnight in your bedroom.

There is a range of “smokeless” ways to beat mosquitoes too. These are either plug-in or butane powered units that heat insecticide impregnated pads, or reservoirs of liquid. Most of these types of units are designed for indoor use but they’ll work just as well in sheltered balconies or courtyards too. Like the insecticide impregnated coils and sticks, these products provide the best bite protection but without the smoke.

You can also forget about the various types of mosquito traps on the market. Some may catch mosquitoes but never enough to stop bites in the backyard. Electrocuting traps and those with UV lights are generally ineffective at catching mosquitoes, you’ll catch many more non-biting flies, moths and beetle than mosquitoes.

birdhouse

Encourage the creatures that will eat mosquitoes

Mosquitoes are food for fish, frogs, birds and bats. Can they help keep mosquito numbers down?

Fish eat mosquito wrigglers so release some (native fish preferably) into your ornamental ponds. Best not release “mosquitofish” (aka the plague minnow, Gambusia holbrooki) as these will chomp through more than just mozzies (say good bye to native fish and tadpoles!). Contact your local council who can provide some advice on what fish may be best suited to your local area. If you’ve got frogs about, tadpoles won’t munch through many wrigglers, but having frogs about is reward enough anyway!

Many claim that encouraging birds or bats to move in around the house will help reduce mosquitoes. A garden of native shrubs and ground covers will provide a home for small insect-eating birds so at least some local animals will be snacking on mozzies. But don’t buy bird houses and bat boxes expecting all the bites to disappear. Although birds and bats do eat mosquitoes, they don’t eat anywhere near enough to reduce nuisance biting. Encourage these creatures because they’re nice to have around, not because they’ll provide pest control.

There are some mosquitoes whose wrigglers will actually eat the wrigglers of other mosquitoes. The news gets even better because these mosquitoes (Toxorhynchites speciosus) don’t even bite (they’re also film stars)! Unfortunately, there will never be enough of them to eat enough mosquitoes to make a difference having them around (as well as other mosquito eating arthropods such as dragonflies, spiders, beetles and damselflies) can only help, even if it is just a little bit.

mosquitorepellentplants

Mosquito repellent plants aren’t repellent

Sounds like a dream that you could plant something in the garden that would “naturally” keep mosquitoes away. Problem is, none of the plants promoted as “mosquito repelling” provide any substantial protection.

Experiments in Africa found that some potted plants repelled around 30-40% of the mosquitoes. I’m somewhat sceptical of that success. Whenever I’ve tested spatial repellents, especially those containing plant extracts that are actively released in one way or another, I rarely get that success. Whole plants? I’m not so sure.

If you check out your local nursery, you may find a plant called “Mozzie Blocker” for sale. This plant is the Lemon Scented Gum (Leptospermum liversidgei). While the extracts from these types of trees (Leptospermum and Melaleuca species) have been shown to repel some mosquitoes, there is no evidence that the whole plant will reduce mosquito bites. It is worth remembering that these plants populate coastal swamp forests and I know from experience that these are some of the most intense places for biting mosquitoes you can find!

In summary, the nuisance caused by local mosquitoes will often be determined by the environment around your home as much as those in it but there are still things you can do to reduce their bites. Most important of all is ensuring you’re not creating opportunities for mosquitoes to breed and hang out in your backyard!

What’s your favourite way to beat the bite of backyard mosquitoes? Join the conversation in Twitter!

Want to learn more about the amazing world of Australian mosquitoes? Check out “A Field Guide to Mosquitoes of Australia” out now through CSIRO Publishing. Over 200 pages containing a pictorial guide to almost 100 different mosquitoes along with tips on beating their bite and protecting your family from the health risks of mosquitoes. You can order online or through your favourite local bookstore or online retailer.