  The host galaxy of the long-duration gamma-ray burst (GRB) 031203 (HG031203)
offers a precious opportunity to study in detail the environment of a nearby
GRB. The aim is to better characterize this galaxy and analyse the possible
evolution with time of the spectroscopic quantities we derive. We analyse
HG031203 using a set of optical spectra acquired with the ESO-VLT and Keck
telescope. We compare the metallicity, luminosity and star formation properties
of this galaxy and of the other supernova-long gamma-ray burst hosts in the
local universe (z<0.2) against the KPNO International Spectroscopic Survey.
HG031203 is a metal poor, actively star forming galaxy (star formation rate of
12.9+/-2.2 {M_{sun} yr^-1) at z=0.1054. From the emission-line analysis we
derive an intrinsic reddening E_{HG}(B-V)\approx 0.4. This parameter doesn't
show a compelling evidence of evolution at a month time-scale. We find an
interstellar medium temperature of 12500 K and an electronic density of
N_{e}=160 cm^-3. After investigating for possible Wolf-Rayet emission features
in our spectra, we consider dubious the classification of HG031203 as a
Wolf-Rayet galaxy. Long gamma-ray burst (LGRB) and supernova hosts in the local
universe (z<0.2) show, on average, specific star formation rates higher than
ordinary star forming galaxy at the same redshift. On the other hand, we find
that half of the hosts follows the metallicity-luminosity relation found for
star-burst galaxies; HG031203 is a clear outlier, with its really low
metallicity (12+\log{{O/H}}=8.12+/-0.04).
