A program to eliminate the exotic mosquito capable of transmitting the dengue virus, Aedes aegypti, has been under way in Tennant Creek since 22 February 2004. This followed the finding of this mosquito via routine adult mosquito trapping on 17 February 2004. Further surveys by the Medical Entomology Branch (MEB) of the Centre for Disease Control (CDC) of the Northern Territory Department of Health and Community Services (DHCS) have indicated to date that the dengue mosquito is firmly established in Tennant Creek. Elimination of this mosquito will take a major effort by health and local authorities as well as by the general public in Tennant Creek.

In Alice Springs, the Ilparpa Swamp is the most productive mosquito breeding site for the common banded mosquito, Culex annulirostris. The swamp is of major public health concern due to potential outbreaks of Murray Valley encephalitis (MVE), with the virus transmitted by this mosquito. In 2001, extensive flooding and two MVEV disease cases led to the first aerial control of Ilparpa Swamp, with aerial control also carried out in 2010. In January 2015, Alice Springs again received heavy rainfall associated with monsoonal activity in the north-east, indicating a possible MVEV disease risk. DoH responded by carrying out another aerial control operation in Ilparpa Swamp, with the successful operation jointly funded by the Power and Water Corporation and the Department of Lands & Planning.

There has been some public concern over a possible increase in blowfly numbers since the introduction of Wheelie bins. Some opinion attributes this possible increase in blowfly numbers to the reduction in bin collection frequency from twice per week to once per week. To aid in resolving the issue the Medical Entomology Branch of the NT Department of Health and Community Services, set up an experiment to determine what link existed between Wheelie bins and blowfly numbers.

Sentinel chicken flocks are used to monitor flavivirus activity in Australia. The main viruses of concern are Murray Valley encephalitis (MVE) and Kunjin which cause the potentially fatal disease encephalitis, in humans. Currently 30 flocks are maintained in the north of Western Australia, 9 in the Northern Territory, 12 in New South Wales and 10 in Victoria. The flocks in Western Australia and the Northern Territory are tested year round but those in New South Wales and Victoria are tested only from November to March, during the main risk season. Results are coordinated by the Arbovirus Laboratory in Perth and reported bimonthly.

The Northern Territory Government proposes to convert Berrimah Farm on the southern outskirts of Darwin, NT into an urban residential subdivision. Areas of Berrimah Farm are located within 1.5km of tidal mangrove areas, and were expected to experience seasonal populations of pest biting midges. Seasonally flooded areas located within and adjacent to Berrimah Farm were also expected to be sources of pest and disease carrying mosquitoes. Due to the potential for significant populations of biting insects, the Department of Planning and Infrastructure (DPI) commissioned Medical Entomology (ME), of the Department of Health and Families (DHF) to conduct a biting insect assessment of the Berrimah Farm site.

A biting insect assessment was conducted at the Andranangoo Creek West and Lethbridge Bay West mining prospects from the 29th September to the 1st of October 2005. This included detailed ground surveys for actual and potential mosquito breeding sites, assessment of aerial photography for potential mosquito and biting midge breeding sites, and initial adult biting insect trapping at both mining prospects. The early report production meant that information from subsequent peak season adult biting insect trapping in November 2005, and January and May 2006 had to be produced in a separate supplementary report. Therefore some conclusions in the first report were drawn based on field inspections and desktop observations, and not on trap data. The following report highlights the findings of the supplementary trapping, with new conclusions in regards to mosquitoes and biting midges. Trapping conducted for the Andranangoo Creek West and Lethbridge Bay West Biting Insect Assessment Report (Warchot & Whelan 2005) is referred to as ‘initial trapping’ in this supplementary report.

Burnside Operations Pty Ltd plan to commence mining at the North Point and Princess Louise mine sites, located in the East Burnside Project Area approximately 130km south-east of Darwin. The mining method will be open cut, with ore to be transported to Union Reefs Gold Mine for processing. Workers are to be housed at the mine camp at Cosmo Village. Mine sites have the potential to create or exacerbate mosquito breeding, potentially from the creation of water dams, wetland filters, borrow pits, sediment traps, dry season water discharge, waste water disposal, as well as the construction of roads and mine waste dumps. Mine sites also have the potential to introduce new mosquito species into the Northern Territory, such as the dengue mosquito Aedes aegypti from North Queensland, if equipment was to be sourced from this area. As part of the environmental process, all major development in the NT is required to consider mosquitoes during the preparation of Environmental Impact Statements or Public Environmental reports, to ensure new development does not create new mosquito breeding sites, and also to protect the health of workers.

Matilda Minerals Limited (Matilda) proposes to develop sand mining operations at Andranangoo Creek West (Andranangoo) and Lethbridge Bay West (Lethbridge), Melville Island, Tiwi Islands, Northern Territory. The proposed operation will extract high grade heavy minerals (HM), specifically zircon and rutile, for export to China. It is estimated that a total of 99,000 t of zircon and rutile will be exported during the anticipated sand mining operation over three and half years. A proposal to mine both sites was submitted to the NT Government in the form of a Notive of Intent Document (URS, 2005). The NT Government determined the project is to undergo formal environmental assessment in the form of an Environmental Impact Assessment (EIS). Part of the EIS process is to conduct a biting insect assessment of the general project areas to determine any public health risks to workers and the potential for mining activities to alter the natural environment and create further biting insect breeding sites. The Medical Entomology Branch was commissioned by URS Australia on behalf of Matilda Minerals to undertake a biting insect assessment at both proposed sandmining sites.

Darwin Clean Fuels Pty Ltd plan to establish and operate a Condensate Processing Facility in Section 5720 and part Section 5633 at the Darwin Business Park at East Arm. The Condensate Processing Facility will produce a range of products, principally unleaded petrol, diesel and kerosene/jet fuel. It is anticipated that the condensate would be sourced principally from the Bayu Undan field in the Timor Sea and North West Shelf off Western Australia. Surface water ponding and mosquito breeding has been an issue in the East Arm area, primarily due to reclamation works conducted for the development of Darwin Business Park and the port facility. Water ponding and mosquito breeding has also been located in Section 5720 and part Section 5633 by the Medical Entomology Branch during previous surveys. The Darwin Business Park is also located adjacent to extensive mangrove areas of Bleesers Creek, Elizabeth River and Hudson Creek, which are expected to be large sources of pest biting midges. Due to the proposed development site and adjacent areas containing potential mosquito breeding sites, and the close proximity of mangrove areas, which are potentially large sources of pest biting midges, the Medical Entomology Branch (MEB) was commissioned by URS Australia Pty Ltd on behalf of Darwin Clean Fuels Pty Ltd to conduct a Biting Insect Assessment for the proposed facility.

A Hazchem Storage Facility is proposed at Section 4239, Hundred of Bagot. Section 4239, Hundred of Bagot is located at Hidden Valley adjacent to extensive mangrove areas of Bleesers Creek and Reichardt Creek in Frances Bay, Darwin Harbour. Section 4239 is proposed to be subdivided in future, with the proposed Hazchem Storage Facility to be built within a 4ha site in Section 4239. The areas adjacent to the proposed development area were also identified as being subject to seasonal pest problems from the salt marsh mosquito Ochlerotatus vigilax (Whelan et al 1994). Other mosquito species of potential significance in the proposed development area include Culex annulirostris and Coquillettidia xanthogaster (Whelan et al 1994). Ochlerotatus vigilax is a vector of Ross River virus (RRV) disease and Barmah Forest virus (BFV) disease, while Culex annulirostris is a vector of RRV, BFV, Murray Valley encephalitis virus (MVEV) disease and Kunjin virus (KUNV) disease. The numbers of these species of mosquitoes in this area indicated there are seasonal risks for mosquito borne disease transmission in the development area. The Medical Entomology Branch (MEB) has been asked to identify any biting insect pest or potential human health problems in the development area, and provide advice on the magnitude of the problem. To do this MEB has referred to past biting insect investigations in the development area (Whelan et al 194), as well as examined the proposed plans for the potential of the development to create or exacerbate existing biting insect problems.

The objectives of the biting insect assessment of the proposed Darwin City Waterfront Redevelopment area is to outline actual and potential biting insect problems within the redevelopment area, and to provide mitigation strategies to prevent or minimise biting insect problems. As with most coastal areas in the NT, the proposed development area is potentially subject to mosquito and biting midge pest problems, and potential mosquito borne disease problems.

The Blacktip Project consists of both offshore and onshore components. The onshore components include the construction and operation of an onshore processing plant, construction and operation of 3km of buried onshore pipeline, and the construction of access roads and construction camp. There were potential biting insect concerns associated with these onshore components of the Blacktip Project. EcOZ Environmental Services was commissioned by Woodside Energy Limited (Woodside) to assist in the preparation of a Draft Environmental Impact Statement (EIS) for the Blacktip Project. EcOZ Environmental Services then commissioned the Medical Entomology Branch of the Department of Health and Community Services to provide information on biting insects likely to affect the Blacktip Project.

Milingimbi is an Aboriginal community in Arnhem Land, 206 km West from Nhulunbuy. The population is 920 (NT government intranet, 30/6/2003). The community is located on Milingimbi Island. Near the end of February 2003 the Milingimbi community council expressed concerns over increased mosquito numbers to Environmental Health, who requested the Medical Entomology Branch to visit the community, assess the situation and advise on strategies to reduce mosquito problems. Two MEB officers visited Milingimbi on 7-9 April 2003 and carried out a comprehensive biting insect survey, including biting insect trapping, larval mosquito surveillance and a receptacle survey. The results of this survey and the assessment are presented in this report. A mosquito survey had previously been carried out in Milingimbi in 1983, and was documented in a MEB branch report.

There are many examples of development in the Darwin region that have led to enormous populations of a range of mosquito species, severely effecting residents in nearby areas and requiring costly rectification. To aid planners in their design of the proposed Newton development, the Medical Entomology section of the department of Health and Families has made collections of biting midges and mosquitoes form march 1984 to April 1985 in and around the proposed development area between the Elizabeth and Blackmore Rivers, south-west of Palmerston. Additional surveys of biting midge breeding areas were made in late 1987. This report analyses the result and suggest methods of minimising the adverse effects of the biting insect present in the proposed development area, and outlines some construction guidelines to avoid exacerbating the problem.

Medical Entomology of the Department of Health and Families (DHF) was requested by the Department of Construction and Infrastructure (DCI) to investigate biting midge abundance in Lot 4243 Town of Palmerston, particularly the area of Lot 4243 between the BMX club and Elrundie Ave/Wishart Rd. Lot 4243 is within the vicinity of tidal mangrove creeks that are known sources of pest biting midges, as revealed by previous baseline investigations around the Durack subdivision (Whelan et al 1998, Shivas & Whelan 2001). The area of Lot 4243 is being considered for the siting of rugby ovals and grandstand facilities, and there is the potential that nearby tidal mangrove creeks could provide appreciable levels of pest biting midges to the subject site.

Biting midges are small blood sucking flies in the family Ceratopogonidae. They are commonly referred to as "sandflies" in northern Australia. The term "sand fly" is a misused term for a number of families of small biting flies. Culicoides ornatus is becoming an increasing problem across northern Australia due to urban development encroaching nearer to their major breeding places. They can impose serious restrictions on outdoor activities within flight range of their mangrove breeding sites due to the extremely annoying and painful bites, and to the discomforting after effects of the bites.

Compass Resources NL is proposing the development of the Browns Oxide mine, located in the Northern Territory approximately 65km south of Darwin and 7km north-west of Batchelor (Figure 1).The project is currently under construction. Compass Resources NL proposes to utilise open cut mining methods and a conventional hydrometallurgical process to extract approximately 3.9 million tonnes of oxide ore and produce copper, cobalt and nickel over a four year period (Public Environmental Report (PER) - Enesar Consulting Pty Ltd 2005). Mine sites have the potential to create or exacerbate mosquito breeding, from the creation of water dams, wetland filters, borrow pits, sediment traps, pit water discharge, waste water disposal, as well as the construction of roads and mine waste dumps. Mine sites also have the potential to introduce new mosquito species into the Northern Territory, such as the dengue mosquito Aedes aegypti from North Queensland, if equipment is sourced from this area. Therefore, all major development in the NT is required to consider mosquito breeding during the Environmental Assessment process, to ensure development does not create new mosquito breeding sites.

Culicoides omatus Taylor is one of the main pest species of biting midge in northern Australia (Reye 1992). It has a coastal distribution from the north of WA to the south of Qld. Its breeding sites are known to occur within mangroves and its presence can create a major pest problem for 1.5 km inland of mangrove areas (Reye 1973, Whelan 1990). Although its larval habitat has been shown to occur around mean high water neap (MHWN) within mangroves in eastern Australia (Reye 1992), previous studies near Darwin have been unsuccessful in identifying its larval habitat (Reye and Lee 1962, Leihne et al. 1985). Darwin differs from eastern Australia in having a very high tidal range of approximately 8 m and very pronounced wet and' dry seasons. This paper discusses the results of a 2 yr study into the distribution of the immatures in mangroves near Darwin. Knowledge of the biology of the immatures is necessary for both assessing the potential of control methods aimed at this stage of the midge's life-cycle and to predict the potential pest problems of land adjacent to mangroves.

The Chronicle is a newsletter that delivers timely updates and summaries on NT and interstate projects, innovations and related activities in the area of chronic disease.

Cockroaches can be significant pest and potential public health problems in the tropics. The guide and recommendations below have been produced with public buildings in mind but can equally apply to private premises. They have been aimed at the German cockroach as they are more common in institutions and residential premises in the Northern Territory but the principles apply equally to the larger American cockroach. They are aimed at the owner or occupier conducting the control, rather than engaging a licensed pest control operator.