At Earth Day’s inception, population growth was central to the conversation, and was linked to rising pollution, resource depletion, and habitat loss.
As population density increases, so too does light pollution, which has become an increasingly widespread environmental concern. Light pollution is defined as the alteration of natural nighttime lighting by artificial sources.
Without immigration-reduction, population growth and sprawl will continue to drive biodiversity losses and degrade Chesapeake Bay’s water quality, commercial fisheries, and overall ecological health.
The right whale is struggling to survive because of ongoing ship strikes and entanglement in fishing gear. With only about 380 left, right whales are one of the most endangered animals on Earth.
Over the past twenty-five years, NumbersUSA has published numerous scientific reports on the causes and consequences of sprawl in the United States. Our most recent study quantifies ecological decline in the Chesapeake Bay and its watershed over the past three decades. Looking forward, we explore a path toward ecological sustainability centered on stabilizing the region’s population through reduced immigration.
If federal immigration policies driving national population growth continue, California’s environment and residents’ quality of life will pay an ever higher price. There can be no sustainability in a context of ever growing human populations.
The border is secure and illegal migration is down. So, do we still need to be concerned about immigration? The answer is an emphatic yes.
Overall environmental conditions in the United States deteriorated in 2025, as the nation continued to add more people to already overburdened ecosystems. As the U.S. population reaches 345 million, the country’s environmental problems increasingly reflect a basic mismatch between human numbers and ecological capacity.
The proposed Delta Conveyance project is designed to service 5.2 million people, less than half of California’s immigrant population. If immigration levels had been lower in recent decades, the project would not be necessary.
