We report precise Doppler measurements of the nearby ( d = 10.34 pc ) M dwarf Gl 649 that reveal the presence of a planet with a minimum mass M _ { P } \sin i~ { } = 0.328 M _ { Jup } in an eccentric ( e = 0.30 ) , 598.3 day orbit .
Our photometric monitoring reveals Gl 649 to be a new variable star with brightness changes on both rotational and decadal timescales .
However , neither of these timescales are consistent with the 600-day Doppler signal and so provide strong support for planetary reflex motion as the best interpretation of the observed radial velocity variations .
Gl 649 b is only the seventh Doppler-detected giant planet around an M dwarf .
The properties of the planet and host-star therefore contribute significant information to our knowledge of planet formation around low-mass stars .
We revise and refine the occurrence rate of giant planets around M dwarfs based on the California Planet Survey sample of low-mass stars ( M _ { \star } < 0.6 M _ { \odot } ) .
We find that f = 3.4 ^ { +2.2 } _ { -0.9 } % of stars with M _ { \star } < 0.6 M _ { \odot } harbor planets with M _ { P } \sin i~ { } > 0.3 M _ { Jup } and a < 2.5 AU .
When we restrict our analysis to metal-rich stars with [ Fe/H ] > +0.2 we find the occurrence rate is 10.7 ^ { +5.9 } _ { -4.2 } % .