Rats Devastate 100,000 Acres California Almond Orchards, Causing $109M-$311M Losses

California's almond industry, valued at $4.7 billion and responsible for more than 75% of global production, is experiencing a severe rat infestation affecting over 100,000 acres, primarily in the Central Valley including San Joaquin, Merced, Fresno, Kings, and Kern counties. The surge in roof rats has caused significant damage to almond trees, irrigation systems, and farm equipment, resulting in estimated losses between $109 million and $311 million, with some reports highlighting damage to 10% of trees per acre and a 20% reduction in nut yields. Experts attribute the infestation to factors such as unplanted farmland due to drought, increased rainfall promoting vegetation growth, pesticide restrictions, and abandoned orchards serving as pest refuges. Control efforts including bait stations, snap traps, fumigation, and owl boxes have proven costly and only partially effective, with rats adapting by burrowing underground and using irrigation canals to spread. University of California-Davis rodent expert Roger Baldwin has become a key consultant for growers, emphasizing the unprecedented scale and urgency of the problem. The infestation poses a substantial threat to a vital agricultural sector that exports 70% of its output to over 100 countries, with ongoing research and training aimed at developing more effective pest management strategies.