Hippocampal lesions do not impair the geomagnetic orientation of migratorysavannah sparrows

The avian hippocampal formation is known to participate in naturally occurr ing spatial behavior such as homing in pigeons and cache recovery in food s toring passerines, but its participation in the often spectacular migration s of birds remains uncertain. As a first investigation into the possible ro le of hippocampal formation in migration, the effect of hippocampal formati on lesions on the geomagnetic migratory orientation of Savannah sparrows wa s examined. When tested indoors, hippocampal formation-lesioned sparrows we re able to orient in an appropriate migratory direction indicating no neces sary role for hippocampal formation in geomagnetic migratory orientation. H owever, hippocampal formation-lesioned birds displayed significantly less m igratory (nocturnal) activity, a result that inspires further study.