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While it is difficult to observe the first black hole seeds in the earlyUniverse, we can study intermediate mass black holes (IMBHs) in local dwarfgalaxies for clues about their origins. In this paper we present a sample ofvariability--selected AGN in dwarf galaxies using optical photometry from theZwicky Transient Facility (ZTF) and forward--modeled mid--IR photometry oftime--resolved Wide--field Infrared Survey Explorer ({\it WISE}) coaddedimages. We found that 44 out of 25,714 dwarf galaxies had optically variableAGN candidates, and 148 out of 79,879 dwarf galaxies had mid--IR variable AGNcandidates, corresponding to active fractions of $0.17\pm0.03$\% and$0.19\pm0.02$\% respectively. We found that spectroscopic approaches to AGNidentification would have missed 81\% of our ZTF IMBH candidates and 69\% ofour {\it WISE} IMBH candidates. Only $9$ candidates have been detectedpreviously in radio, X-ray, and variability searches for dwarf galaxy AGN. TheZTF and {\it WISE} dwarf galaxy AGN with broad Balmer lines have virial massesdown to $10^{5.5}M_\odot$ and for the rest of the sample, BH masses predictedfrom host galaxy mass range between$10^{5.2}M_\odot<M_{\text{BH}}<10^{7.3}M_\odot$. We found that only 5 of 152previously reported variability--selected AGN candidates from the PalomarTransient Factory in common with our parent sample were variable in ZTF. Wealso determined a nuclear supernova fraction of $0.05\pm0.01$\% year$^{-1}$ fordwarf galaxies in ZTF. Our ZTF and {\it WISE} IMBH candidates show the promiseof variability searches for the discovery of otherwise hidden low mass AGN.

Variability-selected intermediate mass black hole candidates in dwarf galaxies from ZTF and WISE