erc-track-exclude-types

erc-track-exclude-types is a variable defined in `erc-track.el'.
Its value is

("NICK" "333" "353")

Documentation:
List of message types to be ignored.
This list could look like '("JOIN" "PART").

By default, exclude changes of nicknames (NICK), display of who
set the channel topic (333), and listing of users on the current
channel (353).

You can customize this variable.