Colcom Foundation, the Pittsburgh-based nonprofit established in 1996 by the late Cordelia Scaife May, pursues conservation through two distinct tracks: regional environmental work across southwestern Pennsylvania and a national education effort grounded in the science of population-environment relationships.
A Two-Part Mission Rooted in Conservation Science
Colcom Foundation’s work rests on a framework known to environmental scientists as I = P × A × T, where total human impact on the environment equals population size multiplied by per-capita consumption multiplied by technological efficiency. Developed by scientists Paul Ehrlich and John Holdren, the equation holds that reducing ecological damage requires attention to all three variables, not just the consumption and technology factors that most conservation campaigns prioritize.
Half of Colcom’s contributions focus on the population variable. The Foundation notes that U.S. population grew 62 percent between 1970 and 2020, from 205 million to 332 million people. Over that same period, per-capita CO2 emissions fell 35 percent, yet total national emissions rose 15 percent — a pattern the Foundation cites as evidence that efficiency gains can be offset by population growth across multiple environmental metrics, including urban sprawl, habitat conversion, and biocapacity consumption.
Regional grantmaking occupies the other half of the Foundation’s portfolio. Colcom funds habitat restoration, watershed protection, parks development, cultural institutions, and community programs across Pittsburgh and southwestern Pennsylvania. Through a partnership with Allegheny Land Trust, the Foundation supported the permanent conservation of 1,470 acres in 2008. That conservation project included Sycamore Island, a 14-acre undeveloped island with a rare floodplain forest and 116 documented bird species. The 1,470 acres represented 40 percent of all land the Allegheny Land Trust protected.
The Peer-Reviewed Literature Behind Colcom’s Approach
Colcom Foundation’s national conservation education work draws on a body of peer-reviewed research spanning multiple journals and institutions.
A 2017 analysis published in BioScience, signed by more than 15,000 scientists, identified rapid population growth as a primary driver of biodiversity loss. Titled “World Scientists’ Warning to Humanity: A Second Notice,” the study stated that “by failing to adequately limit population growth, reassess the role of an economy rooted in growth, reduce greenhouse gases, incentivize renewable energy, protect habitat, restore ecosystems, curb pollution, halt defaunation, and constrain invasive alien species, humanity is not taking the urgent steps needed to safeguard our imperiled biosphere.”
A 2022 study published in Biological Conservation found that “population growth is a fundamental driver of biodiversity loss and population decrease facilitates ecological restoration efforts.” The research examined rewilding outcomes in rural Europe, where declining human population density correlated with documented recovery of mammal and bird species. Research by Radeloff et al., published in PNAS, found that housing growth poses the primary threat to U.S. protected areas, with residential expansion linked directly to biodiversity loss in adjacent conservation zones.
The 2019 IPBES Global Assessment Report on Biodiversity and Ecosystem Services identified demographic and economic growth as underlying drivers of global biodiversity decline. Representing the work of hundreds of scientists, the assessment named “human population trends and dynamics” among the indirect drivers behind the five primary causes of nature loss worldwide.
Colcom publishes its evidentiary record across two sections of its website. The “Our Story” narrative presents U.S. population growth data alongside environmental trend analysis. The “Environmental Ethics” section provides citations to peer-reviewed research, biocapacity calculations from the Global Footprint Network, and data on habitat loss and species decline in the United States.
A Regional Grantmaker With a Documented Conservation Record
Colcom’s regional work in southwestern Pennsylvania spans land conservation, watershed remediation, habitat protection, air quality programs, parks development, and cultural preservation. Individual partnerships and funded outcomes are documented on the Foundation’s Grantee Spotlight and Special Projects pages.
The Allegheny Land Trust partnership is among the most quantifiable. Conservation of 1,470 acres over six years, across parcels that included rare floodplain habitat and an island supporting 116 bird species, was carried out through sustained funder support from the Foundation. That figure amounts to nearly half the land trust’s total protected acreage over three decades of operation.
The Foundation positions its regional and national work as connected expressions of the same underlying principle: that habitat protection at the local level and public education about population dynamics at the national level both bear on the long-term availability of wild land, clean water, and viable ecosystems. The scientific literature it cites in support of that position includes work from Nature Geoscience, PNAS, BioScience, Trends in Ecology and Evolution, and the 2021 Dasgupta Review commissioned by the UK Treasury.
