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Despite the important advances in space asteroseismology during the lastdecade, the early phases of evolution of stars with masses above $\sim$15M$_{\odot}$ have been only vaguely explored up to now. Our goal is to detect,analyze and interpret variability in the early-B type supergiant HD\,2905 usinglong-term, ground based, high resolution spectroscopy. We gather a total of1141 high-resolution spectra covering some 2900 days. We complement theseobservations with the $Hipparcos$ light curve, which includes 160 data pointsobtained during a time span of $\sim$1200 days. We investigate spectroscopicvariability of up to 12 diagnostic lines by using the zero and first moments ofthe line profiles. We perform a frequency analysis of both the spectroscopicand photometric dataset. HD\,2905 is a spectroscopic variable with peak-to-peakamplitudes in the zero and first moments of the photospheric lines of up to15\% and 30 \kms, respectively. The amplitude of the line-profile variabilityis correlated with the line formation depth in the photosphere and wind. Allinvestigated lines present complex temporal behavior indicative ofmulti-periodic variability with timescales of a few days to several weeks. TheScargle periodograms of the {\it Hipparcos\} light curve and the first momentof purely photospheric lines reveal a low-frequency amplitude excess and aclear dominant frequency at $\sim$0.37 d$^{-1}$. In the spectroscopy, severaladditional frequencies are present in the range 0.1 - 0.4 d$^{-1}$. These maybe associated with heat-driven gravity modes, convectively-driven gravitywaves, or sub-surface convective motions. Additional frequencies are detectedbelow 0.1 d$^{-1}$. In the particular case of H$\alpha$, these are produced byrotational modulation of a non-spherically symmetric stellar wind.

Low-frequency photospheric and wind variability in the early-B supergiant HD 2905