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We present deep, narrowband imaging of the nearby spiral galaxy M101 and itsgroup environment to search for star-forming dwarf galaxies and outlying HIIregions. Using the Burrell Schmidt telescope, we target the brightest emissionlines of star-forming regions, H$\alpha$, H$\beta$, and [OIII], to detectpotential outlying star-forming regions. Our survey covers $\sim$6 squaredegrees around M101, and we detect objects in emission down to an H$\alpha$flux level of $5.7 \times 10^{-17}$ erg s$^{-1}$ cm$^{-2}$ (equivalent to alimiting SFR of $1.7 \times 10^{-6}$ $M_\odot$ yr$^{-1}$ at the distance ofM101). After careful removal of background contaminants and foreground M stars,we detect 19 objects in emission in all three bands, and 8 objects in emissionin H$\alpha$ and [OIII]. We compare the structural and photometric propertiesof the detected sources to Local Group dwarf galaxies and star-forming galaxiesin the 11HUGS and SINGG surveys. We find no large population of outlying HIIregions or undiscovered star-forming dwarfs in the M101 Group, as most sources(93%) are consistent with being M101 outer disk HII regions. Only two sourceswere associated with other galaxies: a faint star-forming satellite of thebackground galaxy NGC 5486, and a faint outlying HII region near the M101companion NGC 5474. We also find no narrowband emission associated withrecently discovered ultradiffuse galaxies and starless HI clouds near M101. Thelack of any hidden population of low luminosity star-forming dwarfs around M101suggests a rather shallow faint end slope (as flat as $\alpha \sim -1.0$) forthe star-forming luminosity function in the M101 Group. We discuss our resultsin the context of tidally-triggered star formation models and the interactionhistory of the M101 Group.

A Deep Census of Outlying Star Formation in the M101 Group