  We study the heavy baryon mass spectrum on gauge configurations that include
2+1 flavors of dynamical improved staggered quarks. A valence clover heavy
quark is combined with two improved staggered light quark propagators to form
baryons with different flavors. We are using MILC coarse gauge configurations
with a lattice spacing of about 0.12 fm. In this preliminary investigation, we
explore the chiral limit by studying two light sea quark masses, three
different strange valence quark masses, and nine different light valence quark
masses ranging from 0.1 to 0.4 times the nominal strange quark mass.
