Leptonycteris yerbabuenae is a bat with a distribution range from southern
USA to El Salvador. A distinctive feature of the species is the seasonal accumulation of
subcutaneous fat. Since this specie does not hibernate, it has been speculated that this
energy reserve is used for migration and reproduction or when food availability
decreases. As the role of fat in populations of southern Mexico is unknown, we carried
out this study to determine the fat accumulation pattern and the role it plays during an
annual cycle in a resident colony of this taxon. Results show that males follow a
seasonal pattern, which begins with fat accumulation in February and peaks in May,
right when the mating period begins. After this period, the amount of fat steadily
decreases and disappears during November-January. We also found that the body and
testicular mass are positively related with the amount of accumulated fat and with the
development of an interscapular dorsal patch. Data suggest that stored fat is used for
reproductive purposes and as an energy reserve to stay longer in the breeding colony,
and that the interscapular dorsal patch may be taken as the evidence of reproductive
success.
Keywords: Body mass, Dorsal patch, Fat pattern, Mating behavior, Subcutaneous
fat, Testicular mass.
