TARGETED GRAZING FOR INVASIVE GRASS MANAGEMENT IN THE SAN JOAQUIN DESERT

Steven J Hromada; Fresno Chaffee Zoo; stevehromada@gmail.com; Ranae Sullivan, Emily Bergman, Caroline Mackenzie, Danielle Dillard, Tim Bean, Michael Westphal, Rory Telemeco

Remaining San Joaquin Desert habitats are often dominated by non-native annual grasses which form thick thatch and reduce bare ground, thus degrading habitat for endemic species. This has hindered recovery of blunt-nosed leopard lizard (Gambelia sila; BNLL) and giant kangaroo rat (Dipodomys ingens; GKR). We have been releasing captive-reared BNLL to Panoche Plateau, Fresno County, since 2023; GKR were confirmed to have recolonized in 2024. Dense annual grass cover has hindered BNLL reintroduction efforts. During spring 2025, we established four 2-ha grazing plots on Panoche Plateau and grazed 200 sheep in each for a short period. To document the floral and faunal responses to grazing, we used BLM AIM protocols, released 35 captive-reared BNLL into grazed plots and adjacent roads, and established small mammal mark-recapture plots. Grazed plots had lower herbaceous height and foliar cover, though no difference in bare ground than control plots. Most BNLL released into grazed plots (88%) remained within, and 87.5% of the BNLL released on roads used the plots. GKR detections occurred exclusively on grazed plots, which also had higher captures of Heerman’s kangaroo rats (Dipodomys heermani). Though preliminary, our results suggest that short-term, intensive sheep grazing may benefit San Joaquin desert fauna.

Habitat Restoration and Bees 
Friday 8:45 AM