On this trip we will visit the Ivanpah Valley, roughly 45 minutes southwest of Las Vegas, along the border of California and Nevada. Recently, development has resulted in the loss of roughly 3,200 ha of high quality tortoise habitat. The sweeping views from the north provide context to understand why this landscape is suited for studies of habitat loss, fragmentation, and connectivity. Dr. Dutcher will speak about her research in the area and Scott Cambrin will address goals and objectives from the Clark County perspective.  The Ivanpah Valley is the focal area for ten USGS/UNR research plots that were established in 2015 for the long-term study of desert tortoises in this complex environment. We will visit two of these plots to see anthropogenic disturbances on the landscape, mitigation corridors for connectivity, and hydrological culverts which allow tortoises to safely pass under linear barriers. We will discuss genetic sampling techniques, the functionality of crossing structures and corridors, patterns of emergent population isolation, multi-generational tortoise dispersal (up to 60 km!), and the role of population density in connectivity. We will also search for tortoises (that will likely be tucked into burrows) and scat. Ivanpah Valley is an evolutionary hotspot for tortoises and other species, including western shovel-nosed snakes, desert night lizards, and desert bighorn. To explore connectivity considerations for other taxa, we will chat with a local bird biologist about the valley as a corridor for avian migration, commonly seen southwestern species, and vagrants within the area. We will lunch in scenic and historic Nipton, which was established as a mining camp at the beginning of the last century. The town has served as a refuge for Hollywood stars of yesteryear, a cannabis tourism destination, and a retreat for circus performers. Come enjoy the sites and the science of Ivanpah Valley, an area of central importance to tortoise connectivity range-wide, in a well-studied and rapidly changing classic Eastern Mojave landscape.

In addition to the USGS plots, our second stop will be at the Ivanpah Solar Energy Generating System (ISEGS). We will meet Tim Sisk, NRG Energy, the operator for ISEGS, and Amanda Scheib, Ecocentric-ISEGS Biologist, to see the vegetation on the site.  Rather than clearing the site, the vegetation was mowed to approximately 18 inches.  The growth has been managed regularly since the original mowing in 2010 and 2011.  The status of ongoing desert tortoise studies will also be a topic of conversation.

We will depart the South Point Casino at 0900 on Feb 20 so please arrive by 0845.  The actual meeting place will be determined in early January and all participants will be notified and this description amended. The general itinerary will be to drive to a viewpoint above Primm until 11, ISEGS until 1230, Nipton for lunch until 130, then lastly the USGS site until 330.  Bring water, lunch, snacks, and good walking shoes.  It may be cold and windy so please bring warm clothes.  Expect to walk on flat rocky or sandy surfaces.  Plan on a return of about 4 PM.

Please contact Peter Woodman at email hidden; JavaScript is required for any questions and to register for the trip.  When you register please let Peter know if you can drive and, if so, type of vehicle and number of passengers you can take so he can set up car pools.  While the roads are largely accessible, this field trip does require traveling in a high clearance vehicle.

Interested in recent work in the Ivanpah Valley area? Peter will provide the following:

Brand, L. A., Farnsworth, M. L., et.al. (2016). Mitigation-driven translocation effects on temperature, condition, growth, and mortality of Mojave desert tortoise (Gopherus agassizii) in the face of solar energy development. Biological Conservation, 200, 104-111.

Dickson, Brett G., Scherer, RD, et al. (2019). Multiyear monitoring of survival following mitigation-driven translocation of a long-lived threatened reptile.  Conservation Biology, 33(5), 1094-1105.

Dutcher KE, Nussear KE, et al. (2023) Move it or lose it: Predicted effects of culverts and population density on Mojave desert tortoise connectivity. Plos One 18(9):e0286820

Dutcher KE, Vandergast AG, et al. (2020) Genes in space: What Mojave desert tortoise genetics can tell us about landscape connectivity. Conservation Genetics 21:289-303

Farnsworth, M. L., Dickson, Zachman, BG, et. al. (2015). Short-term space-use patterns of translocated Mojave desert tortoise in southern California. Plos One, 10(9), e0134250.

Hromada SJ, Esque TC, et al. (2020) Using movement to inform conservation corridor design for Mojave desert tortoise. Movement Ecology 8(1):1-18

Vandergast AG, Inman RD, et al. (2013) Evolutionary hotspots in the Mojave Desert. Diversity 5(2):293-319