Holly supports the work of the Fort Huachuca Sentinel Landscape Partnership, led by the US Department of Defense, Department of the Interior, and the Department of Agriculture, to strengthen military readiness, conserve natural resources, and enhance resilience to climate change across a 3-million acre landscape in southeastern Arizona. These science-based planning efforts engage a broad group of public and private partners in the prioritization and implementation of strategies for increasing resiliency for "Sky Island" grassland, forest, and riparian ecosystems.      .

Holly coordinates the science-based adaptive management process for the San Pedro Riparian National Conservation Area, initiated in 2021 under a  Memorandum of Understanding between the US Bureau of Land Management, Fort Huachuca/US Army, Cochise County, and the City of Sierra Vista. The process is described as a "collaborative approach that allows for flexibility under a changing climate and decision-making based on shared science and effective collaboration for regional water management across the boundaries of the SPRNCA and neighboring cities, towns, and military installation".  .     .

Holly provides guidance for the development of regional groundwater management projects to enhance flows and offset human water uses along the Upper San Pedro River with the Cochise Conservation and Recharge Network (https://ccrnsanpedro.org). Responsibilities include strategic planning, fundraising, hydrologic modeling, regional research and monitoring programs, and infrastructure project design and planning in collaboration with local, state, and federal agencies, private foundations, and others.   .

Holly was selected for a Coda Fellowship with The Nature Conservancy from 2021-2022, and focused on developing guidance for groundwater management to conserve freshwater systems globally. Holly worked with conservation practitioners within the Conservancy from around the world to address many aspects of groundwater science and management, including monitoring and metrics, and the assessment of resilience of freshwater systems to a changing climate.  .     .

As Restoration Ecologist with The Nature Conservancy, Holly initiated the binational San Pedro River Wet Dry Mapping Program with the U.S. Bureau of Land Management, a citizen science program still active 25 years later, with dozens of participating groups and agencies and hundreds of volunteers. For maps that are annually produced by The Nature Conservancy as a result of this ongoing effort, showing the wetted length of this river at the driest time of year, go to: https://azconservation.org/project/wet_dry_mapping/. 

During her tenure with The Nature Conservancy, Holly was a founding member of the Upper San Pedro Partnership (https://uppersanpedropartnership.org/), and served multiple leadership positions for this collaborative effort, that engaged 21 local, state and federal member agencies and organizations for more than 20 years.  She served as Chairperson for  their Technical and Executive Committees, and coordinated the development of interagency research, including monitoring, modeling and decision support systems, and helped secure million-dollar  budgets to support the technical needs of federal and local agency programs and projects. Holly continues to serve as one of the Science Advisors for the Partnership's Technical Committee.

Thanks to a scholarship from The Nature Conservancy's Ecosystem Research Program, Holly developed an interdisciplinary ecosystem model for the Yampa River that included geomorphology, hydrology, and riparian ecology, as part of her PhD dissertation from Colorado State University's College of Forestry and Natural Resources. She published this research in the journal Conservation Biology  "Prescribing flood regimes to sustain riparian ecosystems along meandering rivers". 14: 1467-1478.