These data were acquired from 7 study sites distributed across the range of Gopherus agassizii. Data were collected from 1997 to 2002 as part of three separate studies, although data were not collected at all sites in each year. Radio-transmitters were attached to the carapace of 151 females and VHF radio-telemetry was used to relocate animals to assess reproductive status. Egg production was determined from X-radiographs taken weekly/biweekly intervals (depending on the study) using a portable X-ray machine between April and July or August of each year. In addition, the mean carapace length (MCL) of each tortoise was measured at each time of capture or recapture using calipers (mm). A nesting event was recorded if a female previously observed with eggs was observed without eggs during a subsequent X-ray session.

These data were compiled to evaluate the reproductive ecology of Agassiz's desert tortoises (Gopherus agassizzi) in the Sonoran Desert of California using two populations within Joshua Tree National Park, including five reproductive seasons that spanned 20 years (1997-1999, 2015-2016). Compared to their conspecifics inhabiting the Mojave Desert, the reproductive ecology of G. agassizii in the Sonoran Desert is understudied. Climatic variation between the two deserts can affect reproductive ecology, including fecundity and clutch phenology. Mature female tortoises (straight-line carapace length ≥ 20 cm) outfitted with radiotransmitters were located and X-radiographed approximately every 10-14 days during the reproductive season (April-July). The appearance of shelled eggs on X-radiographs allowed for the determination of clutch phenology (dates of appearance and disappearance of shelled clutches), as well as clutch size, clutch number, and X-ray egg width (XREW). XREW was measured at the widest portion of each egg, from the outermost point of each side of the shell, using dial calipers for film and K-PACS software for digital X-radiographs. XREW was determined from the first X-radiograph in which a clutch of eggs was clearly detectable. Data were also compiled on temperature and cumulative precipitation by wet and dry seasons using WestMap (https://cefa.dri.edu/Westmap/), and these data were used to reflect how temperature and precipitation potentially affect reproductive ecology. As a federally listed species, it is important to understand geographic variation in desert tortoise ecology for effective management of the species.

These data were compiled to evaluate the reproductive ecology of Agassiz's desert tortoises (Gopherus agassizzi) in the Sonoran Desert of California using two populations within Joshua Tree National Park, including five reproductive seasons that spanned 20 years (1997-1999, 2015-2016). Compared to their conspecifics inhabiting the Mojave Desert, the reproductive ecology of G. agassizii in the Sonoran Desert is understudied. Climatic variation between the two deserts can affect reproductive ecology, including fecundity and clutch phenology. Mature female tortoises (straight-line carapace length ≥ 20 cm) outfitted with radiotransmitters were located and X-radiographed approximately every 10-14 days during the reproductive season (April-July). The appearance of shelled eggs on X-radiographs allowed for the determination of clutch phenology (dates of appearance and disappearance of shelled clutches), as well as clutch size, clutch number, and X-ray egg width (XREW). XREW was measured at the widest portion of each egg, from the outermost point of each side of the shell, using dial calipers for film and K-PACS software for digital X-radiographs. XREW was determined from the first X-radiograph in which a clutch of eggs was clearly detectable. Data were also compiled on temperature and cumulative precipitation by wet and dry seasons using WestMap (https://cefa.dri.edu/Westmap/), and these data were used to reflect how temperature and precipitation potentially affect reproductive ecology. As a federally listed species, it is important to understand geographic variation in desert tortoise ecology for effective management of the species.

This dataset provides spatial predictions of habitat suitability for Gopherus agassizii (Agassiz’s desert tortoise), Gopherus morafkai (Morafka’s desert tortoise) and a pooled-species model under current conditions (1950 – 2000 yr). The raster layers contained here accompany the manuscript Inman et al. 2019 and were used to evaluate subtle ecological niche differences between Gopherus agassizii and Gopherus morafkai, and identify local species-environment relationships. Spatial predictions of habitat suitability were created using MaxEnt version 3.4.0 (Phillips et al., 2006), a widely-used software for SDM in presence-background frameworks. Detailed methods are provided in Inman et al. 2019. Inman et al. 2019. Local niche differences predict genotype associations in sister taxa of desert tortoise. Diversity and Distributions. https://doi.org/10.1111/ddi.12927

This dataset provides spatial predictions of habitat suitability for Gopherus agassizii (Agassiz’s desert tortoise), Gopherus morafkai (Morafka’s desert tortoise) and a pooled-species model under current conditions (1950 – 2000 yr). The raster layers contained here accompany the manuscript Inman et al. 2019 and were used to evaluate subtle ecological niche differences between Gopherus agassizii and Gopherus morafkai, and identify local species-environment relationships. Spatial predictions of habitat suitability were created using MaxEnt version 3.4.0 (Phillips et al., 2006), a widely-used software for SDM in presence-background frameworks. Detailed methods are provided in Inman et al. 2019. Inman et al. 2019. Local niche differences predict genotype associations in sister taxa of desert tortoise. Diversity and Distributions. https://doi.org/10.1111/ddi.12927

These data refer to habitat and activity data collected for female desert tortoises being monitored as part of a study on juvenile rearing and translocation for population augmentation purposes. The females were affixed with radio transmitters and radio tracked at least monthly to maintain knowledge of whereabouts. During those tracking events activity data were collected (surface or in burrows) and predominate habitat community recorded. Ancillary to this goal a habitat use study was conducted to determine the type of habitat occupied by females. Thus the data reference female morphology, activity, and a single instance of habitat use.

These data refer to habitat and activity data collected for female desert tortoises being monitored as part of a study on juvenile rearing and translocation for population augmentation purposes. The females were affixed with radio transmitters and radio tracked at least monthly to maintain knowledge of whereabouts. During those tracking events activity data were collected (surface or in burrows) and predominate habitat community recorded. Ancillary to this goal a habitat use study was conducted to determine the type of habitat occupied by females. Thus the data reference female morphology, activity, and a single instance of habitat use.

These estimated precipitation data were compiled using the WestMap web site (http://www.cefa.dri.edu/Westmap/). We selected pixels on the map shown on their web site that were in the core of our study areas: one near Palm Springs, California and the other at Sugarloaf Mountain in the Tonto National Forest of Arizona. WestMap uses PRISM data to make point measurements of climate data and a digital elevation model of terrain to create estimates of monthly climate elements. Estimates are derived for a 4km grid, for ease in mapping and GIS applications. PRISM is an integrated set of rules, decision making, and calculations designed to imitate the process an expert climatologist would go through when mapping climate data. We were interested in precipitation data for two hydroperiods: winter precipitation (October-March) and summer precipitation (June-September). These two periods are important for desert tortoise ecology since they trigger germination of food plants in the spring and in the summer.

These estimated precipitation data were compiled using the WestMap web site (http://www.cefa.dri.edu/Westmap/). We selected pixels on the map shown on their web site that were in the core of our study areas: one near Palm Springs, California and the other at Sugarloaf Mountain in the Tonto National Forest of Arizona. WestMap uses PRISM data to make point measurements of climate data and a digital elevation model of terrain to create estimates of monthly climate elements. Estimates are derived for a 4km grid, for ease in mapping and GIS applications. PRISM is an integrated set of rules, decision making, and calculations designed to imitate the process an expert climatologist would go through when mapping climate data. We were interested in precipitation data for two hydroperiods: winter precipitation (October-March) and summer precipitation (June-September). These two periods are important for desert tortoise ecology since they trigger germination of food plants in the spring and in the summer.

This dataset provides spatial predictions of clustering and the genotype association index for the Mojave genotype in local species-environment relationships of Desert Tortoises (Gopherus agassizi and Gopherus morafkaii) for individuals in the subregion encompassing the genetic sampling locations used by Edwards et al. (2015). This region offered an opportunity to explore habitat selection across the ecotone between the Mojave and Sonoran deserts and the secondary contact zone between G. agassizii and G. morafkai, and is referred to as the focal study area. The raster layers contained here accompany the manuscript Inman et al. 2019 and were used to identify multivariate clusters and map them back to geographic space. Inman et al. 2019. Local niche differences predict genotype associations in sister taxa of desert tortoise. Diversity and Distributions. https://doi.org/10.1111/ddi.12927