If you have noticed small black containers like this along your HDB corridors or in public areas, they are known as Gravitraps.
The Gravitraps have been distributed and placed at various parts of Singapore to trap the female Aedes aegypti mosquitoes which transmit dengue and Zika viruses.
The female Aedes adult mosquitoes will be drawn into the dark interior of the container to lay eggs and get trapped within.
The existing network of 50,000 Gravitraps forms a surveillance system that allows the National Environment Agency (NEA) to deploy officers to areas of higher priority.
Earlier in September, NEA said that an additional 14,000 Gravitraps will be deployed to manage dengue clusters in residential areas by the end of 2019.
Misused as ashtrays
A Facebook post by Roads.sg on Nov. 16 highlighted that some Gravitraps placed along the roadsides have been misused as ashtrays.
The lid of the container was removed and unwanted cigarette butts were thrown into the Gravitrap as shown in the photo.If you cannot see the post, here's the photo:
Leave the Gravitraps alone
While such behaviours might be due to ignorance, they nevertheless thwart the efforts in reducing mosquito breeding at dengue clusters.
The Gravitraps help NEA to prioritise its resources in monitoring dengue clusters by allocating more officers to search for and destroy breeding spots based on the number of mosquitoes found in the Gravitraps.
Disruption to the network of Gravitraps may result in delays in tackling the dengue problem in residential estates.
Hence, members of the public are advised not to remove or tamper with the Gravitraps.
Top photo collage via Roads.sg and NEA