Does wetland rehabilitation need mosquito control?

Webb_estuarinewetlands_SydneyOlympicPark_2014Mosquitoes can be more than a nuisance. They pose health risks but could also erode the good will of the community for wetland rehabilitation projects. Wetland rehabilitation needs mosquito control.

It’s a warm February evening. A small and anxious group of residents have gathered in a local community hall to discuss the implications of a local wetland rehabilitation project. Some are angry. One of the first questions comes from an elderly gentleman. Close to tears, he explains how his grandchildren no longer visit due to the plagues of mosquitoes that engulf his property day and night. “What are you guys going to do about it?” he pleads.

I learnt a valuable lesson that night. Trying to explain the best mosquito repellent to use doesn’t go down too well when an audience is facing some significant nuisance-biting impacts around their homes. It doesn’t matter how much DEET is in the repellent, it may well work but is it something you need to wear all day just to get the day to day jobs done around the house? Something more substantial is required and, with hindsight, should have been in place before the first waves of mosquitoes left the local wetlands.

Coastal wetlands are under threat

Sea level rise and climate change  is putting pressure on saltmarshes and urbanisation is eating away land that would otherwise accommodate a landward shift in estuarine habitats. There is nowhere for saltmarshes to spread to so they’re destined to be swallowed up by mangroves. While the mangroves are valuable themselves, they don’t provide the same critical habitats required by many of the internationally protected migratory shorebirds that rely on saltmarshes. Saltmarsh habitats could well disappear from much of the east coast in coming decades if sea levels rise as expected and mangroves continue their march landward.

webb_landinglightswetlandsEstuarine wetlands and mosquitoes

Saltmarshes are home to one of our most important pest and vector mosquito species. While it is important to remember that Aedes vigilax is an Australian native animal and just as much a part of our wetland ecosystems as fish and birds, there is little doubt that it can have substantial impacts with regard to nuisance-biting and the transmission of Ross River virus.

Historically, many of the saltmarshes along the east coast were drained or filled to enable increased cattle grazing (although much of it was under the guise of protection from flooding). Tidal flows were cut off with the construction of levee banks and installation of flood gates. Notwithstanding the impacts of grazing, without tidal exchange, the habitats became brackish water to freshwater dominated systems with a dramatic change in vegetation. Saltmarsh and sedgeland vegetation was steadily replaced by reeds and rushes. Invasive plants such as Phragmites quickly took over many of these wetlands.

webb_floodgates_march2011Bringing back the tides

To combat the degradation of wetlands and impending loss due to climate change, there has been some ambitious wetland rehabilitation projects planned. One of the largest in the southern hemisphere is the Hexham Swamp Rehabilitation Project. Much can be learned from the experience in this wetland just west of Newcastle, NSW, and applied to rehabilitation projects, not only in Australia but overseas as well.

Rehabilitation of Hexham Swamp involved the staged opening of existing floodgates to reinstall tidal flows to an otherwise freshwater system. Many aspects of this project were considered and it is unsurprising that one major issue was the possible impact of mosquitoes. Mosquito populations were something of legend in this area, enough so that there is a “big mosquito” outside the local bowling club affectionately known as “Ossie the Mossie” (coincidently, “Ossie” celebrated her 20th birthday in March 2014).

One of the important considerations when assessing mosquito risk was that there had been a dramatic transformation of the areas surrounding the wetlands in the last 20 years. What was once agricultural land was now residential. This is the same situation right along the east coast of Australia, the rapid urbanisation and swelling residential populations along the coast have put people in the firing line of Aedes vigilax.

The prospect of mosquito control was raised in the early stages of the rehabilitation planning but there was great reluctance from the local authorities to head down that path. The problem is that broad scale mosquito control and ecological rehabilitation are often seen at opposite ends of the wetland management spectrum. I’ve experienced this many times first hand, from scepticism regarding the non-target impacts of biological larvicides to “Apocalypse Now” jokes as helicopters go about routine spraying of local wetlands.

Webb_MosquitoCollectionsIs there such a thing as “environmentally friendly” mosquito control?

The hangover from the actual and perceived impacts of pesticide use more than 50 years ago is still present in the minds of many responsible for managing local wetlands. I say perceived as the development of environmentally sustainable mosquito control programs over the past two decades may not be appreciated amongst those charged with managing wetlands and wildlife.

I feel we need to continue building the case for the range of mosquito control strategies available for our coastal wetlands. Not only do we need to convince local authorities that mosquito populations can be minimised without adversely impacting the local environment but that mosquito control should be a critical consideration in wetland rehabilitation projects. It also has the potential to reduce mosquito-borne disease.

We know that the direct non-target impacts of Bacillus thuringiensis israelensis and s-methoprene are minimal and there is growing evidence that the indirect impacts on local wildlife due to reduced mosquito populations isn’t a major concern. Well-designed projects can also minimise the frequency of treatments while reducing peaks in mosquito activity.

It seems our coastal bats populations are mostly eating moths, not mosquitoes so there is unlikely to be any significant impact on these bats resulting from reduced food. There is no reason why the judicious use of larvicides can’t knock the top off abundant mosquito populations, reduce the pest impacts on local community and not pose a risk to local wildlife. Perhaps it should be considered a critical component of wetland rehabilitation?

redkneeddoteral_kooragangisland_march2015Mosquito control and wetland rehabilitation

In speaking with wetland managers, I try to instil with them the importance of mosquito control. There is a risk that swarms of nuisance biting mosquitoes may erode the good will in the community for wetland rehabilitation. These systems, particularly in the early phases of rehabilitation don’t represent pristine environments and while there may not be a desire to establish ongoing mosquito control programs, some control may prove useful while the wetland comes back into balance with the changed environmental conditions.

Rehabilitation takes time and while there is substantial breakdown of freshwater vegetation it is not going to be ideal for fish and other mosquito predators. It is likely to provide ideal conditions for mosquitoes. Over time, however, fish are likely to increase in both their abundance and penetration into the wetlands and greater tidal flushing will make many of the wetland habitats generally unsuitable for mosquitoes.

Perhaps there is benefit in undertaking control as a show of good will to the local community? After all, engagement with the local community will be critical in the success of wetland rehabilitation projects.

The restoration of tidal flows to Hexham Swamp resulted in an initial increase in the abundance of Aedes vigilax. These increases resulted in substantial nuisance-biting impacts. However, in subsequent seasons, the populations of Aedes vigilax levelled out to comparable levels to those of the surrounding estuarine wetlands. The net result has generally been that the long-term moderate increases in Aedes vigilax populations have been balanced by reductions in Culex annulirostris and Coquilettidia linealis populations as the wetlands shifted from freshwater to saline. The health of the wetlands, as well as the local estuary, is improving.

Mosquito control is only a short-term fix and if the rehabilitation of estuarine wetlands is not carefully planned, there may well be ongoing mosquito impacts. However, reducing any initial impacts will go a long way to ensuring continued engagement of the community with the local wetlands. Cost and the operational considerations may be a barrier for organisations unfamiliar with broadscale mosquito control but these issues can be overcome with the expertise that exists in many parts of the country.

In summary, it is important that mosquito management be considered in the planning process of major wetland rehabilitation projects. There is little doubt that such projects will be required into the future as saltmarsh habitats and other estuarine wetlands are threatened but protection wetlands shouldn’t mean increasing mosquito populations. A balance is required between conservation of environmental health and protection of human health.

A longer version of this article originally appeared in “Mosquito Bites” (the Bulletin of the Mosquito Control Association of Australia).

Managing ‘Mozziegeddon’, Media and Public Health Messages

Sunrise_Mosquitoes

Beer, high tides, public holidays and blood thirsty mozzies. The perfect mix to set the media into a spin. How can you get the best public health messages out about mosquito bite protection?

It was almost as tricky managing the media this summer as it was the mozzies. Since late October, I’ve been interviewed on almost 50 occasions. A mix of pre-dawn calls from radio stations to live crossed to nationally broadcast breakfast televsion to taking talkback and dealing with mobile phone dropouts. It was a sweaty and stressful couple of months….and ‘mozzie season’ still isn’t over just yet.

The last few years have followed a pretty similar pattern. I get my first few calls around August/September. This is usually when we get our first blast of unseasonal heat and there are typically a few stories about people noticing bugs about their home and are worried about an early start to the mozzie season.

Kate_channel9_mosquitotweet

Mozzie season kicked off early

This year we genuinely did have an early start to the mozzie season. The warmest spring on record kicked off the mozzie season early and one of the first big stories I did for Channel 9 News was almost derailed by swarms of mozzies! A few of the crew needed to retreat to the safety of their car. You can listen to me speaking with ABC New Radio here.

Following plenty of rain in early December, mosquito populations starting jumping up along the coast. Just in time for the Christmas holidays. During this period it is pretty common to respond to requests from media to talk about mozzies, particularly if there have been some public health alters from local health authorities.

Getting ready for a live cross to Weekend Today (Channel 9) but what you cannot see in this shot is the hundreds of mosquitoes that were swarming around me, standing in the middle of the mangroves for 20min getting ready for the segment attracted plenty of mozzie attention!

Getting ready for a live cross to Weekend Today (Channel 9) but what you cannot see in this shot is the hundreds of mosquitoes that were swarming around me, standing in the middle of the mangroves for 20min getting ready for the segment attracted plenty of mozzie attention!

A few things helped keep mozzies in the news. There were health warnings from local authorities after the detection of Ross River virus in southern Sydney. There were warnings about a new outbreak of dengue in Far North QLD. Flooding in central Australia also prompted warnings of outbreaks of mosquito-borne disease.

Then there was this piece I wrote on why mosquitoes bite some people more than others that attracted plenty of attention too….over 1.2 million readers in fact (thanks to republication by IFLS, SBS and Mamamia)!

Moztralia Day Mozziegeddon

As we headed towards our national holiday weekend and Australia Day celebrations, there were warnings that a big boost in mosquito populations were on their way. Yes, “mozziegeddon” was coming and the pesky little biters were set to turn our long weekend into a “moztralia day bloodbath“. Worse still, those taking part in the traditional Australia Day past time of beer drinking were being scared off the booze by fears of becoming “mozzie magnets“.

mozziegeddon_news_palzanetti

“Mozzigeddon” turns Australia Day into Mozztralia Day! Great cartoon by Paul Zanetti accompanying a story at News.com

There is little surprise that stories about beer drinking and mozzies attract plenty of attention. It does almost every year. However, this year was a little different because health authorities were concerned about potential increases in mosquito populations and given recent detections of mosquito-borne pathogens such as Ross River virus, there was concern about public health risks. Those risks range from both the north coast of NSW to north-west of WA!

There was plenty of mosquito media coverage from SE QLD too. Local authorities were battling big mosquito populations and trying to control “3000 known mosquito breeding sites” the next generation of mosquitoes hatching following heavy rain and tidal flooding of local wetlands.

Local insect repellent manufacturers were also taking advantage of the boost in mosquito numbers. I’ve noticed an increase in tv and radio ads spruiking mosquito repellents and Aerogard also sent out “swat” teams to local parklands around Sydney on Australia Day promoting their “Mozzie Index“* website!

Aerogard "Bite Busters" hit the prime picnic spots around Sydney on Australia Day

Aerogard “Bite Busters” hit the prime picnic spots around Sydney on Australia Day

How could this media interest help spread the word on effectively stopping mosquito bites?

In the lead up to the long weekend I spoke with the breakfast show on 2UE (you can listen to the interview via link), Angela Catterns on 2UE, Chris Smith on 2GB as well as Robbie Buck and Linda Mottram on 702 Sydney. I provided a couple of brief grabs for news bulletins and even did my first live cross for the Sunrise breakfast program on Channel 7. You can also listen to interviews with 2SER, ABC Perth and ABC South East SA. [update 26 February 2015. There were a few more interviews, one fun one was with Richard Stubbs for 774 ABC Melbourne and you can listen in below, another was with Dom Knight on 702 ABC Sydney and you can read about that here. and I also chatted with Patricia Karvelas on Radio National Drive and you can listen here.]

It can be tricky getting good public health messages out during these very brief interviews, particularly for television. Radio can be pretty good as there is often plenty of time to get the message out (sometimes even time for talk back callers and questions) but for some of the commercial stations, time can be brief. Television is particularly challenging, I usually spend more time in the make up chair than being interviewed!

This summer I’ve been determined to ensure some key messages get out, particularly about choosing and using insect repellents most effectively. This is an issue I feel strongly about and I have an article coming out shortly in the Medical Journal of Australia on how local health authorities can do this a little better.

The two key messages were “if you’re using botanical based topical repellents, they need to be reapplied more frequently than the recommended DEET and picaridin based repellents” and “when using repellents, they must be applied as a thin coat over all exposed skin to get the best protection, not a dab here and there”.

Overall, I think I managed to get these two points into most radio and television interviews and I was happy to see that the general message got through in a lot of the print/online media too.

Below are some of my tips on getting a specific message out while dealing with the media.

1. Prepare. You would practice giving a conference presentation ahead of time so why not prepare for media? Think about the messages and how you can deliver them. What questions might you get asked? What will be the style of the presenter? Are there any questions you may be asked that you may want to avoid answering (e.g. questions of a political nature or something that could embarrass your employer)? How can you do that?

2. Learn from the professionals. If know you’re going to do some media in the coming weeks or months. Spend some time listening to talk back radio and reading newspapers. Take note of the number and length of quotes journalists use in articles. Make their job a little easier by providing concise quotes where possible. How do radio broadcasters conduct interviews? Listen to politicians and journalists being interviewed. How do they get their message across (or don’t in some circumstances). What makes you “switch off” from an interview – is it the topic or interviewee?

3. Create bridges between questions and your message. This is the thing I’ve found quick tricky but once you’ve got the hang of it, you can more effectively get the message out. There may not be a question asked that specifically relates to the message you need to get out. Learn how to transition from a brief response to the question asked onto the key messages you want to get out there. Don’t just launch off into your spiel at first chance, it is important to engage with presenter too, its a subtle art but like all things, it is only hard before it becomes easy.

4. Post-interview review. I’ll often take notes after an interview that help prepare for the next one. Things like the type of questions asked or how I answered questions, particularly if I feel my responses were clunky or I rambled a little! I’ve always found it interesting that slight differences in the way that questions are asked can often throw you off balance in an interview. If there are talkback callers, what questions were asked, especially if there was something out of left field! Making a note of these can help when preparing for the next batch of media.

5. Keep track of media activity. You never know when it may come in handy when applying for a promotion, grant or new job. I try to keep track of all media activities by recording the date, journalist, media outlet and brief description of topic. You can also speak to your local media and communications unit to see if they gather statistics on these things too. The team at the University of Sydney are great and it is fascinating to compare the analysis of different media activities, their reach and estimated value.

Perhaps the trickiest thing in all this is assessing whether this media activity actually helped the community prevent mosquito bites. It will be almost impossible to tell from human notification data on mosquito-borne disease given the numbers jump around so much from year to year anyway. What really need is some more attitudinal studies to see how people seek out and follow advice provided by local health authorities on mosquito-bone disease prevention strategies. Another thing for the “to do” list

Webb_NineNews_March2015[update 21 March 2015] Following the detection of Ross River virus amongst mosquitoes collected in NSW combined with a dramatic increase in human notifications of Ross River virus disease, there was another wave of interest by local media. You read a piece at the Sydney Morning Herald and watch a segment with me from Nine News.

Why not join the conversation on Twitter?

*A disclaimer: I provided some assistance to a local PR company back in 2012 that developed the “Mozzie Index” for Aerogard, particularly some info on the associations between mosquitoes and local environmental conditions.

Australian mosquitoes discovered in California: What does it mean?

AedesnotoscriptusThe movement of mosquitoes around the world is more likely to drive the spread of mosquito-borne disease outbreaks than a changing climate. Health authorities received yet another reminder of how easily pest mosquitoes can move about with human activity. They can sneak in and set up home before we even know they’re there.

Mosquitoes deserve more credit. We’re impressed with the adaptation of birds, fish and frogs to narrow ecological niches or extreme environments. How about showing the same respect for these insects that have left behind their life in tree holes or leaf axils and moved into our cities. They’ve switched tastes from primates to people and their pets. They may only fly short distances but we help move them around the world with increasing frequency accompanying globalisation and discounted airfares.

Exotic mosquitoes and international travel

Long before planes made the planet a much smaller place, we were already moving mosquitoes massive distances. It could probably be argued that the brown house mosquito, Culex quinquefasciatus, first came to Australia in water filled barrels with the first fleet and the movement of the Yellow Fever mosquito, Aedes aegypti, and associated pathogens from the Caribbean to Philadelphia and triggered a catastrophic outbreak of disease in 1793.

In more recent times, the spread of the Asian tiger mosquito, Aedes albopictus, has been well documented and has raised concerns amongst international health authorities with regard to outbreaks of disease caused by dengue and chikungunya viruses.

This week saw the announcement that a mosquito, Aedes notoscriptus, had made its way from (most likely) Australia to California. The news attracted plenty of attention from media in Australia and North America. The mosquito discovery was due to the diligence of two agencies in Los Angeles, The Greater Los Angeles County Vector Control District and San Gabriel Valley Mosquito and Vector Control District. The joint media release from these two agencies described the discovery and identification:

“During an expanded search this summer for the invasive Asian tiger mosquito, staff from the San Gabriel Valley Mosquito and Vector Control District (SGVMVCD) and the Greater Los Angeles County Vector Control District (GLACVCD) collected unusual specimens from a couple of homes. After someinitial research, photographs of the mosquito were sent to Dr. Cameron Webb and John Clancy with theMarie Bashir Institute of Infectious Diseases and Biosecurity at the University of Sydney, Australia and they confirmed it to be Aedes notoscriptus.”

 

This was a great example of international collaboration. There was also little doubt that without the availability of high quality photographs we wouldn’t have been able to offer such a rapid identification. Not so long ago we would have had to ship specimens back and forth to confirm identification.

What does this mean for California?

Apart from questions regarding how this mosquito made it half way around the world, the critical issue now is to assess what pest or public health risk this mosquitoes poses to Los Angeles, California and North America more generally.

Aedes notoscriptus (commonly referred to as the ‘backyard mosquito’) is widespread in Australia. From the cold climates of Tasmania to the tropical north of the country. The mosquito is also found in New Zealand, Western Pacific and Indonesia.

The mosquito is closely associated with urban areas. Eggs are laid in a wide range of natural and artificial water-holding containers. There are very few Australian’s who haven’t been bitten by this mosquito. It is a constant companion at summer BBQs and is considered a nuisance-biting pest, mostly biting in the afternoon and early evening. However, it does have broad tastes when it comes to blood feeding. The abundance of this mosquito is relatively low compared to some of our “wetland” mosquitoes (such as Aedes vigilax and Culex annulirostris) and the mosquito doesn’t fly far, generally less than 200m.

The low natural dispersal of the mosquito is thought to have contributed to the emergence of subpopulations in some regions of Australia. More recent studies have found that phylogenetic analyses of DNA sequence data from mitochondrial markers indicate the mosquito is a complex of divergent genetic lineages, some geographically restricted, others widespread. There is, however, no doubt assisted movement of mosquitoes is also occurring around the country. As with any container-inhabiting mosquito, human movement will drive the spread of this mosquito in North America.

From a public health persepctive, Aedes notoscriptus is a less significant nuisance-biting pest than Aedes albopictus and Aedes aegypti. However, it is a vector of arboviruses and parasites. Aedes notoscriptus is an effective vector of Ross River and Barmah Forest viruses. A range arboviruses have also been isolated from field collected specimens in many parts of the country and the mosquito has been implicated in Ross River virus transmission in major cities including Sydney and Brisbane. Neither Ross River virus or Barmah Forest virus are known to exist in California.

Fortunately, the mosquito is generally not considered an effective vector of dengue viruses, West Nile virus, Yellow Fever virus or, chikungunya virus but it has been shown to be susceptible to Rift Valley fever virus. Aedes notoscriptus is an effective vector of dog heartworm, Dirofilaria immitis.

How did it get there?

We may never know. Mosquitoes can be moved about in lots of different ways, from cargo holds in aircraft and ships to baggage and belongings of individuals. Industrial, mining and agricultural equipment may provide a route of movement too.

Given that established populations have been discovered, it may be more likely that personal belongings may have been moved to California from Australia or New Zealand with travellers or family relocating for work. Perhaps surveys of the local community, combined with genetic analysis of the specimens will help answer this question.

The take home message for local authorities, both in California and Australia, is that the mosquito did make the trip, slipped through the cracks of quarantine and become established. While this introduction may not pose a significant impact to California, the introduction of Aedes albopictus to Australia could have far more substantial impacts. If we can export our mosquitoes, we should remain vigilant of the potential for exotic mosquitoes to find their way to us from Asia, Europe or the Americas.

What should authorities do?

There are already strategies in place for the surveillance and control of container-inhabiting mosquitoes in California. These strategies would prove effective in tracking and controlling Aedes notoscriptus. The one advantage authorities have is that Aedes notoscriptus is readily collected in carbon dioxide baited light traps whereas Aedes albopictus and Aedes aegypti are generally not collected as often by these traps.

In summary, the mosquito should not be considered a major pest or public health risk. The priority for local authorities should remain the other container-inhabiting species such as Aedes albopictus and Aedes aegypti. Notwithstanding these species, other mosquitoes associated with urban environments, particularly Culex spp., are currently playing an important role in one of the largest outbreaks of West Nile virus. In fact, the “proportion of mosquitoes infected with West Nile virus is at the highest level ever detected in California“.

Californian authorities have enough on their plate without the extra worry of an Australian hitchhiker turning up and moving in!

The wonderful photo of Aedes notoscriptus at the top of this post is provided by Jared Dever, Direcror of Communications, at Orange County Vector Control District.

What can the outbreak of dengue in Japan tell us about future mosquito-borne disease risk?

dengue_japantimesConsidered free of dengue for around 70 years, Japan is now facing an outbreak of mosquito-borne dengue virus centered around a popular Tokyo city park. How could this happen?

Dengue is typically associated with tropical regions. However, outbreaks of dengue have occurred in temperate regions historically. That includes major outbreaks in Japan. In fact, dengue has been a notifiable disease in Japan since 1999; regulated by the Infectious Disease Control Law.

The last major outbreak was in 1942-1945. Breaking out in Nagasaki in August 1942, over 200,000 cases were suspected to have occurred, making it one of the largest temperate zone dengue outbreaks on record. It is interesting that, at the time, there was an extensive network of water tanks to enable response to fires triggered by bombing during the war. These tanks supported “innumerable” populations of the Asian Tiger Mosquito, Aedes albopictus. Also contributing to the problem was an inability to undertake large-scale insecticide applications at the time.
Then, for around 70 years, dengue disappeared. Until 2014.
Local authorities This picture taken on August 28, 2014 shows a worker spraying insecticide at the Yoyogi park, one of the largest open spaces in central Tokyo, believed to be the source of the mosquito-borne dengue fever. An outbreak of dengue fever in Japan -- the first since World War II -- could have affected up to 20 people, media reported on September 1, as officials confirmed three more cases.      (Photo Source: AFP via ABC News)

Local authorities undertake spraying in Tokyo’s Yoyogi Park. (Photo Source: AFP via ABC News)

The first case of dengue in this current outbreak was reported at the end of August 2014 but in the space of a week or so, many more cases were identified. To date (9 October 2014) there has been a total of 151 confirmed locally acquired cases of dengue (this includes an Australian traveller). The majority to these cases have been centred around the popular Yoyogi Park in Tokyo.

[update 1 November 2014] Tokyo’s Yoyogi Park finally reopened after the outbreak was first detected but it was closed for 57 days. As well as a serious inconvenience to the people of Tokyo, there is little doubt this has had a substantial economic impact on the city. It would be fascinating to know if the outbreak impacted tourism.

[update 5 December 2014] A newly published paper reports on the molecular analysis of isolates of dengue virus from 19 confirmed cases of infection from Tokyo. The analysis showed that the outbreak was triggered by a single incursion of dengue virus type 1 (DENV-1) and that analysis of the envelope protein genome sequence from 3 patients revealed 100% identity with the strain from the first patient.

Some of the media coverage has focused in the role that climate change may have played on triggering this outbreak. However, the outbreak is not the result of a changing climate. International travel and a cool climate tolerant mosquito are to blame. Perhaps complacency regarding the risks associated with this mosquito predisposed the region to this outbreak too?

aedes_albopictus_SteveDoggett

The Asian Tiger Mosquito, Aedes albopictus. (Source: Stephen Doggett, Pathology West – ICPMR Westmead)

The Asian Tiger Mosquito, Aedes albopictus, is a cool climate tolerant mosquito closely associated with water holding containers in urban environments. The mosquito is a severe nuisance-biting pest and second only to the Yellow Fever Mosquito (Aedes aegypti) in its importance in transmitting dengue virus. It is also very effective at transmitting chikungunya viruses. The expanding range of Aedes albopictus internationally is of critical importance to outbreaks of the disease. It is raising concerns regarding the transmission of chikungunya virus in North America this year.

Aedes albopictus provided the tinder that an infected traveller ignited to kick off this dengue outbreak.

There were warnings this was coming. Much of the media coverage has emphasised that this is the first local outbreak of dengue in 70 years. In fact, there was an intriguing case last year that should have put local authorities on notice.

In January 2014 there was news that a German tourist had contracted dengue. In Japan.

In a published case report, a woman sought treatment in a hospital in Berlin, Germany, in after returning from two weeks of travel in August-September 2013 to Honshu Island, Japan. Her travel route was via Frankfurt International Airport to Tokyo Narita International Airport and return. She did not visit any regions considered to have endemic dengue activity. The authors note that this case was “the first recognised case of locally acquired dengue (DENV) infection in Japan for more than 60 years”.

Following this reported case, authorities undertook surveys that revealed high population densities of Aedes albopictus within the urban areas of Japan. It is interesting to note that, despite using a surveillance method that is typically not effective at collecting Aedes albopictus (carbon dioxide baited light traps), some of the largest densities of mosquitoes were collected from Tokyo. Interestingly, a 2010 study into the blood feeding behaviour of Aedes albopictus in Japan showed that over 68% of mammalian blood meals identified were human and the authors concluded that the mosquito may play a role in outbreaks of dengue and chikungunya viruses.

I cannot find any reports of mosquito control, either source reduction or insecticide treatment, were undertaken in response to these findings.

Average number of Aedes albopictus collected using human bait collection and CDC miniature traps in urban areas of Japan (Source: International Journal of Infectious Diseases)

Average number of Aedes albopictus collected using human bait collection and CDC miniature traps in urban areas of Japan in September 2013 (Source: International Journal of Infectious Diseases)

There are clearly some warnings that authorities, both in Japan and elsewhere, should take from this event. Most importantly, the presence of Aedes albopictus should not be underestimated in increasing the risk of local dengue outbreaks. While the published report of the dengue infection in the German tourist prompted debate (see here and here) about the future of local dengue outbreaks in Japan, it is clear now that where Aedes albopictus occurs, so does the risk of dengue. Control of this mosquito should be undertaken, not only to reduce the nuisance-biting impacts but to also reduce public health risk. Clearly, August and September seem to be a high risk period around Tokyo.

While locally acquired cases of dengue were unknown since the 1945, Japanese travellers were regularly returning home infected with the pathogens. A recent study of 540 Japanese travellers demonstrated that, not only was Indonesia and the Phillippines destinations of high risk, but that August and September were peak periods when infected travellers were returning home from these endemic regions. An eerie coincidence considering the cases in August/September in both 2013 and 2014. Where these traveller, not climate change, triggered outbreaks in Japan? (the debate about climate change driven dengue outbreaks in other regions of SE Asian could be left for another day)

Rate of reported dengue cases per 100 000 travellers by month and countr y visited,* Japan, 2006–2010

Rate of reported dengue cases per 100 000 Japanese travellers by month and country visited, 2006–2010. It is interestign to note that only data for 2010 on travellers to Indonesia is reported. (Source: Western Pacific Surveillance Response Journal)

Australian authorities should take note of what has happened in Japan. While understanding the routes of entry of Aedes albopictus into new regions is critical, developing strategic surveillance and control responses to the introduction of the mosquito are of equal importance.

Since the discovery of Aedes albopictus in the Torres Strait in 2005, there has been much debate, together with data crunching and computer modelling, with regard to the possible spread of the mosquito across the mainland. There is evidence that the mosquito can survive at cooler climates in Australia and can spread some of our local pathogens. What will it mean for Australia to have a severe nuisance-biting pest and potential vector of dengue and chikungunya viruses inhabiting our major cities such as Brisbane, Sydney, Melbourne and Perth?

We should be mindful that this mosquito may not naturally spread south from the north, it may sneak in through the back door. It already has. The mosquito was discovered, and fortunately eradicated, from Melbourne in 2012. Exotic mosquitoes continue to be intercepted at our ports.

Perhaps we can’t stop Aedes albopictus reaching mainland Australia. Efforts continue to keep the mosquitoes at bay but, in reality, we may be overwhelmed. We cannot fill enough cracks to stop them slipping through.

What we need are strategic responses to the incursions of the mosquito. Authorities need to build capacity for quick response surveillance and control. Traps and insecticides are cheap, expertise on the ground by those responsible for catching and killing the mosquitoes is not. The traps and control measures currently used to control pest mosquitoes associated with wetlands will not be easily be transferable to the control of container-inhabiting mosquitoes. We need to review our approaches to mosquito control should Aedes albopictus be introduced. Time may be on our side for the moment but for how long? Will we one day see outbreaks of dengue in Sydney’s Centennial Park?

Why not join the conversation on Twitter?

Can social media help track environmental change?

saltmarshrehabilitation_KGIA picture may well tell a thousand words but what if that picture is tweeted, shared and liked? Could social media help engage the community with local wetlands? Could it assist in crowd sourced tracking of environmental change?

After the fire comes the photos

Using photography to track post-bushfire environmental change is common in Australia where bush fires are a part of life. Scientific publications and technical reports produced across the country have used “before and after” photos to highlight the dramatic change, and equally dramatic recovery, seen in the Australian bush after fire.

How can we incorporate social media in tracking this post-fire recovery? Perhaps it could even play a role in boosting the spirits of the local community seriously impacted by bushfire? The recovery of communities is as important as recovery of the environment. A recent study has highlighted the importance of social networks in the community and perhaps opportunities to share interactions with the environment through social media would provide further opportunities for engagement.

Bushfires are a natural part of the Australian environment and photography plays a key role in reminding us that our vegetation can respond remarkably after even the most intense fires (Source: CSIRO)

Bushfires are a natural part of the Australian environment and photography plays a key role in reminding us that our vegetation can respond remarkably after even the most intense fires (Source: CSIRO)

An example of engaging social media in bushfire recovery comes out of California. I’m particularly taken by the use of social media as a critical component of the program tracking recovery from bush fires that swept through Mt. Diablo in 2011. The project is coordinated by the Nerds for Nature team, inspired by the initiative of Sam Droege and his Monitor Change project.

The idea is based around members of the community taking photos at set locations with set perspectives and compiling those photographs shared through social media, to create a crowd sourced time lapse animations of post-bush fire recovery (you can read a little more about it here). What makes this so neat is the simplicity. Clear signage and a simple bracket for lining up your camera/phone. The website interface is great too. The team behind the project have provided some detailed instructions that form a great basis for adapting this approach to a local environment (they also point out that this project may not be as simple to implement as you may think…).

Tracking bushfire recovery with crowd sourced photographs! (Originally tweeted by Sergei Krupenin in reference to Nerds for Nature program)

An Australian take on crowd sourced “environmental change” photography

Another example of using photography to track environmental change is the Australian Fluker Post project. Similar to the approach by the Nerds for Nature team, this project, coordinated by Dr Martin Fluker at Victoria University, is a “citizen science system designed to allow community members to contribute towards the ongoing care of various natural environments by taking photographs”.

“Fluker Posts” are installed at key locations and members of the community can use their own cameras to take photos and then email them to coordinators. As well as collecting material to assist local land managers, this project may have a more subtle influence on conservation by engaging the community with the local environment. By providing an opportunity for local residents (as well as regular visitors) to track the changes in their local environment, it would be hoped that a connection and care for the local environment would increase. As well as directly changing behaviour that may threaten local habitats or wildlife, the community (and by extension local decision makers) are more likely to be supportive of rehabilitation efforts.

An example of a newly installed Fluker Post ready to help track environmental change (Source: The Fluker Post Project)

An example of a newly installed Fluker Post ready to help track environmental change (Source: The Fluker Post Project)

You can see examples of photos from the various Fluker post locations here but you can also keep up to date with various projects at the Fluker Post Facebook page. A relatively new venture has just kicked off using this “technology” to engage with school students – a great idea!

Tracking tidal changes

Another great example of crowd-sourced tracking of the potential environmental change is the  Witness King Tides program. The program is coordinated by Green Cross Australia and calls of members of the community to submit photos taken during king tide events (the highest of the spring tides each month) to help generate an indication of what may happen in the future with sea level rise. There is a wonderful collection of photo albums here from across Australia.

This idea of a crowd-sourced collection of photographs tracking tidal events has been tried in the past. Most notable was a collection of photos contributed to by over 250 people taken during a major tide event in 2009. A useful document was produced by NSW Office of Environment and Heritage. It highlights an important issue in relation to potential impacts of sea level rise. The first wave of impacts may not be catastrophic but they will be disruptive.

While images of major cities underwater often accompany media reports of rising sea levels and plans for adaptive responses, in many parts of Australia, increasing frequency of these “higher than usual” tides will cause disruption to cities and townships in other ways. Blocking stormwater systems, forcing the closure of roads and delays with ferry services. In addition to this, there is the increasing risk of coastal erosion and loss of amenities in coastal regions.

SOPA_kingtides

“Before and after” shots of a cycleway through Sydney Olympic Park in January 2014. Higher than expected spring tides flooded many of the pathways, cycleways and boardwalks in the local area causing much disruption; perhaps a sign of things to come if rising sea levels make these event more frequent.

One of the problems with this method, however, is that these photographs end up being “one offs”. Without a comparison to “normal” conditions, it can sometimes be difficult to gauge the significance of tidal inundation without being familiar with the local area. Fortunately, there are many examples where contributors send both “before” and “after” tidal inundation shots and they do provide a stunning visual representation of the disruption sea level rise may cause. Perhaps the incorporation of “photography points” (following the examples from the Flucker Post or Nerds For Nature teams) at key locations would be a useful addition to the program?

This approach has been adopted bytThe City of Manduarh in Western Australia with their  Tidal Image Mandurah Project. The community has been asked to take photos at key locations with a view that images of tidal events such as storm surges, high tide and erosion will help track change. Nothing too fancy in these locations either, just a strategically placed spray painted blue camera!

An example of the spray-painted blue camera on a beachside post inviting members of teh community to take and share a photo of Florida Beach (Source City of Mandurah)

An example of the spray-painted blue camera on a beachside post inviting members of the community to take and share a photo of Florida Beach (Source: City of Mandurah)

Tracking constructed wetland change

Where would I like to see this implemented? I’ve had the opportunity to work in and around many newly constructed wetlands. These have ranged from small freshwater wetlands in urban areas to extensive rehabilitated estuarine wetlands. The common denominator across all these sites has been vegetation change. I cannot be out there every week taking photos but it would be great if there was a collection of photos being shared by the local communities that I could tap into.

There are some great examples of interpretive signage around our local wetlands. There is also a shift in thinking from traditional interpretive signage to take advantage of new technologies so why not include social media to engage visitors and local community further? Perhaps social media networking should be included in wetland management plans?

Signage at Gungahlin Wetlands, ACT

Signage at Gungahlin Wetlands, ACT. An example of structures associated with urban wetlands that can be modified to include opportunities for social media use through the use of recommended hashtags (for Twitter or Instagram) and/or brackets for placing cameras/smartphones

A simple addition of a bracket and details on sharing photographs could easily be incorporated into local signage as it is installed and/or updated. As well as tracking changes in vegetation growth in and around constructed and rehabilitated wetlands, the encroachment of mangroves into mudflats or sandy shores along urban estuaries could be a focus too. Of course, storm events and unusually high tides could be documented too. An added bonus would be if some rare or unusual wildlife popped up in photographs.

Educational signage of this nature are common place around wetlands in Sydney, could the inclusion of some guidelines for social sharing images help track mangrove incursion into shoreline habitats?

Educational signage of this nature is common place around wetlands in Sydney, could the inclusion of some guidelines for social sharing images help track mangrove incursion into shoreline habitats?

There are plenty of other ways social media can assist environmental conservation and rehabilitation. Pozible and Landcare have recently announced the launch (and called for the submission of proposals) of a new global crowdfunding partnership called The Landcare Environment Collection, an opportunity to showcase and support the crowdfunding campaigns of environmental groups in Australia and around the world.

Perhaps I need to prepare a proposal for the installation of some “social sharing” camera stands…

Why not join the conversation on Twitter and help share other examples of where social media could help track environmental change.