Private forest reserves in Brazils agricultural landscapes effectively sustain the occupancy and abundance of multiple threatened large vertebrate

1. Understanding the factors that shape wildlife abundance and distributions is at the core of applied ecology and wildlife management. Accurate predictions on the population level outcomes of land management are especially urgent in biodiversity hotspots around the world that are undergoing rapid transformation. In South America, both the Cerrado and Amazon are increasingly being converted to agricultural land-uses to produce soybean and corn and raise cattle. Over the last several decades Brazil has become one of the leading global producers of these products. At the same time, Brazil has some of the strongest federal regulations focused on protecting native habitat. The Native Vegetation Protection Law (or the Forest Code) requires private properties retain native vegetation as Legal Reserves, and as a result more than half of the countrys remaining native habitat now lies on private lands. Whether retained habitat under this ambitious policy sustains populations of large, wide-ranging vertebrates across entire agricultural production landscapes remains untested. 2. Here, we conducted a landscape scale survey using camera-trap stations across ~606,000 km2 of Mato Grosso, Brazils largest producer of cattle, soybean and corn. We sampled 115 independent sites between November 2024 and September 2025, spanning both crop seasons. We estimated occupancy of jaguars and expected abundance of white-lipped peccary and lowland tapir, using a combination of occupancy and Royle Nichols models. We fit an abundance-mediated interaction model to formally test the role of prey abundance in driving jaguar occupancy across the landscape. 3. We found high occurrence and expected abundance of all three species. Forest cover was the only covariate common to all top models for every species: predicted jaguar occupancy probability rose as forest cover increased and expected peccary and tapir abundance also increased as a function of forest cover. 4. Our empirical estimates from abundance-mediated interaction models were consistent with jaguar occupancy being a function of both habitat availability and prey (peccary) abundance. 5. Synthesis and applications. Native forest retained on private land under Brazil's Forest Code is associated with the persistence and local abundance of an apex predator, a megaherbivore and a keystone ungulate across one of the world's most intensively farmed regions. Jaguar occupancy rose from 0.33 to 0.87 as forest cover increased from 15% to 65%, indicating that maintaining Legal Reserve requirements is central to retaining large vertebrates in production landscapes. Private reserves should be managed as complements to, not substitutes for, protected areas and Indigenous territories, and habitat-retention policy should be paired with mitigation of crop damage and livestock depredation to prevent retained forests from becoming ecological traps. Our framework provides a transferable approach for evaluating habitat-retention policies for wide-ranging species elsewhere.