Larval Mosquito Monitoring

The Larval Mosquito Monitoring menu is aimed at allowing you to enter larval mosquito data through a three-step process, which you will be guided through after selecting the site location.

The Larval Monitoring menu can be chosen by clicking on the Monitoring menu and selecting Larval Mosquito Monitoring.

Larval mosquito monitoring menu

Selecting the Larval Mosquito Monitoring menu

Please note: that before you can setup a Larval Mosquito Monitoring Site, you will need to already have set up the Site (if it is new) in the Sites screen.  For more information on how to set up a Site, please see the appropriate help page.

Please note throughout the website if you see fields marked with red asterisks (*) then these are Mandatory fields, and must be filled out before you can save the form you are working on.

The first page of the Larval Mosquito Monitoring menu allows you to input information on larval monitoring sites

The Larval Mosquito Monitoring menu

Of the five fields on the Larval Mosquito Monitoring menu, four are mandatory.  These include:

  • Site – a mandatory field indicating the site location where the dipping for larval mosquitoes takes place;
  • When – a mandatory field for the time and date of the dipping exercise.  This field is automatically completed with the current time and date when you click on the tab.  It can be manually overwritten by typing over the current characters or by changing the date with the calendar function on the right hand side of the field.
  • Trap Type: a mandatory field for the type of dipping technique used.
  • Sampling Officer: a mandatory field where you specify your name or initials
  • Dry Site: this toggle field allows you to tag a site as dry. Any subsequent data entry relating to larval dips and stages for a dry site will result in a pop-up message to ensure valid data entry.
  • Location: Optional field for a different trap location. This should provide a description of the area, such as a distinctive landmark.
  • Type: Optional field for the type of trap found in the other location.

Below these fields are an additional three tabs that include:

  • Environment – allows you to record a range of environmental variables at the time of sampling;
  • Dips – allows you to record the number of larvae per dip; and
  • Instar – allows you to record the approximate percentage of larvae observed within each instar class.

larval tabs

The four tabs of the Larval Mosquito Monitoring records

If you are using the website, you will need to do most of the data entry all at once.  The website is best used when you have completed multiple larval samples, so that you can populate the Dips, Instar, Spot Treatment and Environment tabs at one time for each sample.

Dips Tab

The Dips tab allows you to enter the approximate number of larval mosquitoes within a series of dips at each location.  To help standardise the number of larvae per dip, a range of images have been provided as a guide.  These images include an approximate count of:

  • 10 larvae per dip;
  • 50 larvae per dip;
  • 100 larvae per dip;
  • 500 larvae per dip;
  • 600 larvae per dip;
  • 750 larvae per dip; and
  • 1000 larvae per dip.

These images scroll through from one to the next automatically, but can also be scrolled through by clicking on the white transparent arrows in the centre of each side of the images (see image below).

The Larval Mosquito Monitoring Dips tab

Below the images is a field that automatically calculates the average number of individual mosquito larvae when two or more dips are taken at a site. You now have the ability to simply add your own value in this field.

The two methods here reflect slightly different practices in Western Australia and Victoria.

In the example below, the average of the two dips (875 and 500) are added and divided by the total number of dips (2) to obtain an average of 688 larvae per dip at this site.

Example of the Average number of larvae per dip calculations

After dipping the water source, the number of larvae in the scoop are assessed (refer to the images above) and the estimated number of larvae entered into the field “Dip 1:”.  If multiple dips are taken, values can be added to fields “Dip 2:” through “Dip 10:”.  A maximum of ten dip estimates can be recorded on any one day at any one site.

Please note: the average will re-calculate after each dip value is added.

Once you have chosen these values, you should move on to the next tab.

Please note: that if you hit the “Save Larval Record” button after just filling in these fields above, you will be asked to fill out the mandatory fields across all tabs before you can save the record. Once you have completed all fields on a single tab, you should click on the next tab to continue data entry.

Instar Tab

The Instar tab allows you to estimate the number of larvae at each instar stage.  This is particularly important if chemical treatment is required, as the active ingredient to be used to kill larvae is likely to change between early and late instar stages.


The Larval Mosquito Monitoring Instar tab

The Percentage Total is a shaded field (data cannot be entered on this form) that automatically adds all of the instar stage percentages together to provide an overall percentage.  This figure cannot add up to more than 100% and acts as a guide as Environmental Health Officers enter percentages across the instar stages.  The instars cover 5 stages of larval growth including:

  • Instar stage I;
  • Instar stage II;
  • Instar stage III;
  • Instar stage IV; and
  • Pupae.

Spot Treatment

The Spot Treatment tab allows you to enter chemical spot treatments where you have treated a site while conducting larval dips.  In this tab you can enter one or two products (e.g. chemicals from an approved list) and quantities used at the site.

The following fields are available:

  • Treatment Required: This allows you to specify if a treatment is required at that site, with No selected by default. If you select Yes, at least one Product and Quantity must be specified before you can save the record.
  • Product Used: You can select a chemical from a drop-down list of approved products. In most cases the Product name contains the brand, the product and units (e.g. kg, briquettes, ml).
  • Quantity: a numerical field where you enter the amount of a chemical used in the spot treatment. The value corresponds to the unit type of the product selected.
  • Comments: a free text field to enter information relating to the spot treatment.


Environment Tab

A range of environmental variables have been included to provide data that can later be used for analysing mosquito abundance, species composition and diversity.  Five environmental variables are automatically populated from the nearest Bureau of Meteorology weather station to the site – but you also have the ability to enter your own field observations. This weather data integration works when you select a site, and the information comes through so long the recording time is within 72 hrs of the current time.

The top of the form is split into Field observations on the left, and Bureau of Meteorology Observations (grey boxes) on the right. Below that the Contextual Environmental Data contains a number of variables where you can enter values from local observations or other information sources.

The available fields include:

  • Air Temp (°C) – The air temperature at the time dipping was conducted in degrees Celsius.  A range of values can be added between -10 to 50°C;
  • Humidity (%) – The relative humidity at the time of dipping, expressed as a percentage.
  • Cloud Cover (%) – The percentage of cloud cover observed at the time dipping was undertaken;
  • Wind Direction – Direction of wind selected from a drop down box of 16 choices when the field is clicked upon;
  • Wind Speed (Km/h) – estimated wind speed in kilometres per hour from the drop down selection provided.  This includes:
    • Not recorded – no wind speed recorded at time the trap was set;
    • Calm – low wind;
    • Light (<20 km/h);
    • Moderate (20-30 km/h);
    • Fresh (30-40 km/h);
    • Strong (40-50 km/h); or
    • Gale (>50 km/h).
  • Last Significant Rainfall Date – The date of the last significant rainfall to affect the site (added manually or by using the calendar on the right of the field);
  • Last Significant Rainfall (mm) – The amount of rainfall at the time of the Last Significant Rainfall Date (above) in millimetres;
  • Last Significant High Tide Date – Date of the last significant tide near the dip site (added manually or by using the calendar on the right of the field);
  • Last Significant High Tide (cm) – Height of the last significant high tide recorded at your dip site (in centimetres);
  • Water Temp (°C) – The temperature (in degrees Celsius) of the water at the time of sampling.
  • Current Water Depth at site (cm) – The current depth (centimetres) of water at the location being sampled.
  • pH – the acidity of the water at the time of larval sampling (between 0 and 14), and,
  • Comments –  A free text comments box to add any information about the site that may be useful or explain mosquito abundances at a later date.


The Larval Mosquito Monitoring Environment details tab

By selecting a site you will notice automatically captured values appear in green, and details of the nearest weather station, including the Station name, distance from the site, and the date/time of the latest weather observation.


The Larval Mosquito Monitoring Environment details tab with automated weather data capture

You can click on the “Show all data” button to see the raw data from the Bureau of Meteorology, and the formatted equivalent the system will record against he larval monitoring record.


The “Show all data” button and pop-up of raw and formatted weather data

Once you have entered your Environment data, you should save the larval record before proceeding.  Hit the “Save Larval Record” button to save the information.  When you do this, you will be taken back to the Larval Mosquito Monitoring menu where you will be able to review any of the completed fields across all tabs as per the image below:

Larval Mosquito Monitoring save notification

Save notification after completing a Larval Mosquito Monitoring tab

Please note throughout the website if you see fields marked with red asterisks (*) then these are Mandatory fields, and must be filled out before you can save the form you are working on.