The opening 60-minute edition, from the corporation's natural history unit held a largely stable audience throughout but managed to peak eith 8.9 million (32.4%) halfway through.
The prestigious programme, that took four years to make, managed to outperform recent high profile natural history programmes on BBC1. Life in the Undergrowthin November 2005, in a similar 9pm slot had 4.9 million (19%) while Life of Mammalsin January 2002 appealed to 6.2 million (23%).
Panet Earth 's sister series, Blue Planet, also got off to a cracking start in September 2001 with the first episode drawing 9.7 million (37.2%).
ITV1's two hour whodunnit Midsomer Murderscouldn't quite match BBC1 despite adding an extra 400,000 viewers from the previous week. The second instalment of the current series averaged 8.4 million (34.9%).
The spoils went to the commercial network at 8pm as the final part of Wild at Hearttook 9 million (35%).
It comfortably had the edge over BBC1's celebrity singing contest Just the Two of Uswhich ended its run, also at 8pm, on 6.1 million (23.5%).
With both the two main terrestrial broadcasters dominating viewing the remaining channels had to fight over the scraps.
BBC2's Facing the Truthconfronted 1 million (3.6%) at 8pm while Top Gear: the Challenges!, an hour later, had 1.7 million (6.2%).
Channel 4's Invasionfound a reasonable 1.8 million (6.9%) but a re-run of The 100 Greatest Pop Videosfrom 9pm managed just 800,000 (7.7%).
Five turned its entire peaktime schedule to films. Sphere at 7.30pm drew 1.1 million (4%) while Starship Troopers 2: Hero of the Federationat 10pm found 1.5 million (9.3%.
All-hours shares for Sunday 5 March 2006: ITV1 - 22.6%, BBC1 - 21.4%, BBC2 - 7.2%, C4 - 7.1%, Five - 5.9%, multichannel - 35.8%.
Peaktime (7pm-10.30pm) shares: ITV1 - 35%, BBC1 - 26%, BBC2 - 5%, Five - 5%, C4 - 4%, multichannel - 25%.