York University (England) have carried out work using radio-tagged ants. However, the method is currently limited to collected data from individual ants as they pass a fixed point. Otherwise, the ants could be marked in some way to identify and observe individual behaviour (e.g. dot of coloured paint). 

Paint is by-far the most common method; however, work done in my own lab has attempted to advance methods for intranidal observations. I have not been able to publish on this methodology, as my research has since gone in a different direction. The strategy still depended upon individual labeling of ants before placement into arena (with appropriate filming apparatus), but it also utilized QR codes instead of unique color combinations. These QR codes were designed to be tracked using a video analyzing program written in Python. The lab technicians who inherited my contributions, as far as I am currently aware, were not able to perfect the method. In my opinion, if one were to optimize this strategy, one would need to incorporate an embedding of an algorithm recognizing individual over-lap and a respective-observation history that is upkept with each experimental set up (this would prevent oversight in individual counts and could correct upon missed ants or ants that have left to forage, etc.). There are many open-source algorithms available online that could facilitate this objective (i.e., IBM Watson's visual recognition software is currently available to all who wish to incorporate use of the API into their own apps, etc.).

Hi,

you can use paint, is the best method. Look for some articles from Deborah Gordon, she did some great experiments painting ants.

https://scholar.google.es/citations?user=_e5OvWgAAAAJ&hl=es&oi=ao

Dear Chiawen, I hope you have a nice day.

As Colbie and Pedro said, the best method to track and identify ants in the colony is painting the target ants. This method also was used to track individual bees in the entire beehive. Personally, I used this method to track and identify some individual ants related with intrafloral and extrafloral nectaries. For me, this method was very useful to distinguish each ant in the plants.

This method also was used to track individual bees in the entire beehive. Personally, I used this method to track and identify some individual ants related with intrafloral and extrafloral nectaries. For me, this method was very useful to distinguish each ant in the plants.

Personally, I used this to track and identify some individual ants related with intrafloral and extrafloral nectaries. For me, this method was very useful to distinguish each ant in the observed plants.

Best regards, 

Cristian