Bummer was a black-and-white Newfoundland or Newfoundland cross who established himself outside the saloon of Frederick Martin in 1860 and quickly proved to be an exceptional rat-killer.  His ratting talent spared him the fate of the former owner of the territory, Bruno, who had been poisoned with strychnine shortly before Bummer's arrival. According to a 1901 retrospective published in the "San Francisco Call", he had been owned by Ned Knight, a reporter for the "Daily Alta California" and had followed him to San Francisco from Petaluma. He scraped a living begging scraps from passers-by and the patrons of the saloon and other establishments along Montgomery Street.