California Pronghorn Likely Tables Migration Corridors

The Likely Tables herd contains migrants, but this herd does not migrate between traditional summer and winter seasonal ranges. Instead, much of the herd displays a nomadic tendency, slowly migrating north for the summer using various high use areas as they move. Therefore, annual ranges were modeled using year-round data to demarcate high use areas in lieu modeling specific winter ranges. A high use area being used during winter by many of the collared animals is west of the Warner Mountains, east of U.S. Highway 395, and north of Moon Lake. Some animals live in the agricultural fields west of U.S. Highway 395. There appears to be little if any movement across the highway, which is fenced on both sides in this area. Summer ranges are spread out, with some individuals moving as far north as Goose Lake. A few outliers in the herd moved long distances south toward the Lassen herd or east to Nevada. Drought, increasing fire frequency, invasive annual grasses, and juniper encroachment negatively affect pronghorn habitat. Recent population surveys indicate a declining population (Trausch and others, 2020). Juniper removal on public and private lands have potential to improve habitat quality and potentially reduce predation (Ewanyk, 2020). Fences on public and private lands affect movement corridors and increase crossing and/or migration times. Recent fence modifications on BLM lands have shown potential to ease pronghorn movements (Hudgens, 2022). These mapping layers show the location of the migration corridors for pronghorn (Antilocapra americana) in the Likely Tables population in California. They were developed from 29 migration sequences collected from a sample size of 17 animals comprising GPS locations collected every 1-4 hours.

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  "geospatial"
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