In the early 1990s, I went on a vacation to Bali. There were a range of indigenous geckos, emblematic to the local culture, which are around 120 millimetres long as adults and partially transparent. These geckos have an incredible ability to climb even on glass surfaces and ceilings.
At the time, I admired their ability to hunt mosquitoes and small insects. The coastal areas of northern NSW and S.E. Queensland, and I understand Perth and the Northern Territory, have seen the rise of these aliens in urban and rural settings. Whilst I admire their ability to reduce pest insect numbers, they are becoming an introduced species to compete in infamy with the introduced Cane Toad.
The Sunshine Coast has been invaded by alien geckos, who have a nasty attribute of gluing their droppings on all surfaces, such that any unwashed outdoor area or alfresco BBQ is likely to have a plethora of gecko droppings deposited in a few weeks. There have also been insurance claims that were not covered by warranty due to geckos becoming stuck in the intakes and electrical mechanisms of split system air conditioners, causing extensive damage and cost.
The gradual warming in temperature has also allowed tropical cockroaches to survive winter inside without the seasonal reduction seen previously. Tropical termites have been slowly migrating and extending their range. The incidence of dengue fever in Cairns has become a major concern, as has the spread of tropical diseases such as chikungunya and malaria. Climate change is a serious threat to bio-security and public health.
Is it time our public infrastructure and building codes, and our electrical and plumbing codes, began to prepare for the likely consequence of an increase in the range and scope of pest species and organisms?
Let us consider termites and borers as an example. These insects currently destroy and damage properties of an extensive area. However, the termites from the Northern Territory and northern Queensland, previously unknown in the South, have begun to take a bridge head. Soil micro-organisms which can cause serious illness and death may also extend their range previously above Gladstone, and migrate south as winters become milder and the cooler periods in the sub tropics abate.
Less well understood is the migration of large predators. Salt water crocodiles may be easily able to survive mild winters and extend their range. Great white sharks are now known to migrate to Moreton bay to breed whereas previously their range was to remain in the waters south of Moreton Bay. Will they adapt to warmer conditions, or will they retreat south?
Moreton Bay before European settlement had large areas of coral and reef. Tropical fish and species have been noted by divers and fishers to be migrating and extending their range.
Other pest species include seagulls and ibis, which have become well fed on our urban dumps. They have increased in numbers to the point where one must conclude they are in plague proportions. Large flocks of seagulls and ibis are displacing other native species and are voracious killers of native wildlife and other birds’ young. Serious consideration should be considered to cull their numbers as an environmental disaster. I have witnessed seagulls killing native and migratory birds on the barrier reef, and feed all year on coastal dump sites.
Bat colonies have invaded urban areas in periods of severe drought, and when colonies are distressed they can harbour serious pathogens such as the Hendra virus.
Another pest species has been fire ants, and although great efforts have been undertaken to eradicate their nests, because the climate in our sub-tropical areas is so similar to their native South America, they have proven extremely difficult to control.
Standing water is likely to become an issue as mosquitoes harbor and spread a number of diseases, such as Ross River fever, malaria, and the Zika virus. In our public infrastructure and in our residences, greater monitoring and measures should be introduced to reduce the incidence of mosquitoes.
How could the changing climate and incidence of invasive species and pests be reflected in building and health codes?
Our hygiene regulations and building codes have been designed to reduce the incidence of tropical diseases such as legionnaires in air conditioning, greater measures should be required in Northern NSW and Perth.
Our kitchens in commercial settings and residences should be modified to improve the hygiene and cleanliness of surfaces, and reduce the areas where vermin can hide and breed. High-rise and medium density housing, as well as commercial kitchens, need to consider measures to reduce vermin such as mice and rats, and to implement cool areas for waste storage. A casual inspection of the back of house of many restaurants and kitchens reveals that they are often havens for vermin and pathogens.
The cleaning of public areas in commercial buildings, hospitals, multi-residential areas and lifts may require to be codified and monitored. Many viruses are spread by contact with residue from infected persons. What exposure is there, for instance, in an 80-storey residential tower in a lobby through which thousands move every hour?
Building codes should reflect the more aggressive nature of pathogens and introduced vermin to public health and to the impact on the environment and native fauna and flora.
When you next see a beautiful gecko introduced from Indonesia and South East Asia, you should do well to also consider the local species which have been displaced.
Insurance rates for all forms of property have been impacted by adverse and extreme weather. In the near future, introduced species and pathogens which have moved beyond their normal range are likely to cause extensive damage and health impacts unless our hygiene and construction codes are modified to account for the predicted two degree minimal warming which is anticipated over the next 50 years.
Alien reptiles, pathogens, insects such as tropical mosquitoes, termites and other timber borers as well as fungi in residential settings should be considered a higher priority in any revision of Australian standards and building codes.