Daily relative dog abundance, fecal density, and loading rates on intensively and minimally managed dog-friendly beaches in central California

Highlights: • Intensively- and minimally-managed dog beaches had similar dog fecal densities. • Dogs were estimated to load 0.2 and 1.4 MT (7 and 10 g/m²) of feces on study beaches yearly. • Beach location was associated with increased fecal deposition. • Season and beach wrack also were associated with increased fecal deposition. • Areas located near beach entrances should be targeted for education interventions. - Abstract: Due to increased concerns regarding fecal pollution at marine recreational beaches, daily relative dog abundance and fecal density were estimated on an intensively managed (Beach 1) and a minimally managed (Beach 2) dog beach in Monterey County, California. Fecal loading and factors predictive of fecal deposition also were assessed. After standardizing for beach area, daily beach use and fecal densities did not differ between beaches and yearly fecal loading estimates revealed that unrecovered dog feces likely contributes significantly to fecal contamination (1.4 and 0.2 metric tonnes/beach). Detection of feces was significantly associated with beach management type, transect position relative to mean low tideline, presence of beach wrack, distance to the nearest beach entrance, and season. Methodologies outlined in this study can augment monitoring programs at coastal beaches to optimize management, assess visitor compliance, and improve coastal water quality.