  We have analyzed JHKL observations of the stellar population of the ~9
Myr-old eta Chamaeleontis cluster. Using infrared (IR) colour-colour and
colour-excess diagrams, we find the fraction of stellar systems with near-IR
excess emission is 0.60 pm 0.13 (2_sigma). This results implies considerably
longer disc lifetimes than found in some recent studies of other young stellar
clusters. For the classical T Tauri (CTT) and weak-lined T Tauri (WTT) star
population, we also find a strong correlation between the IR excess and H_alpha
emission. The IR excesses of these stars indicate a wide range of star-disc
activity; from a CTT star showing high levels of accretion, to CTT - WTT
transition objects with evidence for some on-going accretion, and WTT stars
with weak or absent IR excesses. Of the 15 known cluster members, 4 stars with
IR excesses delta(K-L) > 0.4 mag are likely experiencing on-going accretion
owing to strong or variable optical emission. The resulting accretion fraction
(0.27 pm 0.13; 2_sigma) shows that the accretion phase, in addition to the
discs themselves, can endure for at least ~10 Myr.
