Agassiz's desert tortoise and egg data from the Sonoran Desert of California (1997-2000, 2015-2018)
Data for journal manuscript: “Unscrambling” the drivers of egg production in the Mojave desert tortoise: Climate and individual attributes predict reproductive output
Dates
Publication Date
2020-09-03
Time Period
1997
Time Period
1998
Time Period
1999
Time Period
2000
Time Period
2016
Time Period
2017
Time Period
2018
Citation
Puffer, S.R., Lovich, J.E., and Cummings, K.L., 2020, Agassiz's desert tortoise and egg data from the Sonoran Desert of California (1997-2000, 2015-2018): U.S. Geological Survey data release, https://doi.org/10.5066/P97XT7HF.
Summary
These data were compiled to evaluate reproductive output of Agassiz's desert tortoises (Gopherus agassizzi) in relation to environmental and individual-level variables. We collected data from four study sites in the Sonoran Desert of California, including two separate populations within Joshua Tree National Park, one population located on the northern versant of the Orocopia Mountains, and one population located at the extreme western end of the Coachella Valley. These data represent eight reproductive seasons that spanned over 20 years (1997-2000, 2015-2018). These data were compiled and added to a larger database with additional records collected by other scientists from eight other study sites in order to detect drivers of reproductive [...]
Summary
These data were compiled to evaluate reproductive output of Agassiz's desert tortoises (Gopherus agassizzi) in relation to environmental and individual-level variables. We collected data from four study sites in the Sonoran Desert of California, including two separate populations within Joshua Tree National Park, one population located on the northern versant of the Orocopia Mountains, and one population located at the extreme western end of the Coachella Valley. These data represent eight reproductive seasons that spanned over 20 years (1997-2000, 2015-2018). These data were compiled and added to a larger database with additional records collected by other scientists from eight other study sites in order to detect drivers of reproductive output in G. agassizii across its range. In our studies, mature female tortoises (straight-line carapace length ≥ 200 mm) 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 reproductive status, clutch sizes and number, and total annual egg production (TE). As a federally listed species, it is important to understand variables affecting desert tortoise reproductive ecology for effective management of the species.
The purpose of these data are to provide a better understanding of the environmental and individual-level variables affecting reproductive output of Agassiz's desert tortoises. These data were added to a much larger dataset that included records collected by other scientists on reproductive output in female tortoises across a total of 12 study sites. All of these data related to egg production were used to build a range-wide predictive model of reproductive output as a function of climate variation and individual-level attritubutes (body size and prior-year reproductive status). As a conservation-reliant species, having a better understanding of the variables affecting desert tortoise reproductive output will allow for more effective management of the species.
Rights
The author(s) of these data request that data users contact them regarding intended use and to assist with understanding limitations and interpretation. Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty.
Preview Image
Jeff Lovich, Ph.D., with tortoise near Palm Springs