Transportation infrastructure has fragmented previously contiguous habitat and reduced connectivity among populations of the Mojave desert tortoise (Gopherus agassizii). Over 55,312 km of roads exist throughout tortoise habitat. Tortoise road mortality is a significant issue relative to recovery of this species. Therefore, the U.S. Fish and Wildlife Service (USFWS) has identified installation of permanent exclusion fencing with culvert crossing structures as a significant priority for desert tortoise recovery. If crossing opportunities are inadequate or culvert structures are not conducive to movement of tortoises, connectivity among adjacent habitats may be permanently altered resulting in subdivision of desert tortoise populations and fragmentation of habitat. Identifying effective culvert designs that best facilitate tortoise movement is crucial for this species' survival and recovery. We used data from camera traps to evaluate the safety and functionality of culvert designs for desert tortoises. We installed eighteen motion sensitive camera traps where attached to both ends of nine tortoise-specific wildlife pre-existing corrugated metal drainage culvert underpasses of various lengths and diameters, which are located along US 93, where tortoise fencing has been installed. Seventy-one motion sensitive camera traps were installed along a portion of US 95 where tortoise fencing and ten concrete box culverts had recently been constructed. Tortoises were observed entering and crossing through both corrugated metal drainage culverts and concrete box culverts at various rates. Openess factor does not appear to be a significant factor for determining whether a tortoise will enter and cross through a culvert. In fact, tortoises appear to exhibit a preference for the smaller diameter corrugated metal culverts because of their similarity to burrows, which they use for shelter and thermoregulation. On several occasions, tortoises have been observed to enter the culverts and remain in them for extended periods of time, while other individual tortoises were observed to frequently complete crossings in short periods of time. Adult tortoises were more likely to enter and cross through upon approach to the entrance of a culvert than juvenile tortoises. The concrete box culverts presented several safety issues because they were designed for dual purpose to function both as crossing structures for tortoises and to address hydrological issues, such as heavy sheet flow during storms. The USFWS and the Bureau of Land Management collaborated with the Nevada Department of Transportation to develop modifications to the concrete box culvert designs that would address safety issues for tortoises while allowing for hydrological functionality. We will continue to monitor these culverts with our camera traps to evaluate the functionality of our modifications and effects of seasonal climate variation to tortoise use and movement.