How effective is camera trapping in monitoring grassland species in the southern Pampas ecoregion?

We assessed the efficiency of camera trapping in monitoring bird and mammal species in the grasslands of Tandilia Mountains by calculating the naive occupancy, capture rate, and time to the first detection for each species. We compared the observed richness with the reported richness from online databases. We performed species accumulation curves to estimate the sampling effort necessary to detect bird and mammal species. We detected 50 bird and 15 mammal species. The top 5 bird species (Chalk-browed Mockingbird, Rufous-collared Sparrow, Rufous Hornero, Great Pampa-Finch, and Spotted Nothura) accounted for 48% of all detected individual birds, with naive occupancy of 21-25% and mean times for the first detection between 6 and 9 days. The top 5 mammal species (Pampas fox, large hairy armadillo, European hare, Molina's hog-nosed skunk, and Geoffroy's cat) accounted for 81% of all detected individual mammals, with naive occupancy of 32-77% and mean times for the first detection between 4 and 7 days. A sampling effort of 2 weeks was the optimal balance between effort and result qualities. We detected all the reported richness of mammals and half of the reported grassland-associated birds. We provide valuable information for future grassland species monitoring with camera trapping in Neotropical grasslands.