Green’s Dictionary of Slang

(orig. Aus.) a homosexual man; thus tan-tracking, anal intercourse (irrespective of genders incolved).

1984		J. Green Dict. Contemporary Sl. 281/2: tan-tracker n. (Aus. use) homosexual male.
1985		‘Thommo’ Dict. Aus. Swearing & Sex Sayings 128: TAN TRACKIN’ — Anal intercourse male or female.
1986		B. Hudson First Aus. Dict. Vulgarities n.p.: tan tracker, an aggressive homosexual.
1992		Aldrich & Wotherspoon Gay Perspectives 44: Ride the tan track and tan-track rider and dirt-track rider are only marginally less blunt. The same idea is involved in the variants on chocolate.