The polar bear, Ursus maritimus, is an apex predator whose survival is closely tied to the health of the sea ice ecosystem. As a species uniquely adapted to the harsh northern environment, its population status serves as a powerful indicator of broader environmental changes. The period around 1970 represents a particularly significant benchmark in the history of polar bear conservation efforts. This era marked a low point for the species, prompting an international response that changed its trajectory from a heavily exploited animal to a globally managed species. Understanding the historical numbers from that time provides a necessary context for appreciating the conservation challenges faced today.
The Historical Estimate of the Early 1970s
The question of how many polar bears existed in 1970 does not have a single, definitive answer, as robust, circumpolar scientific surveys did not exist. Estimates from the period were highly uncertain, based on limited observation, local knowledge, and extrapolations. The consensus among conservationists was that the global population was severely depleted.
Many historical accounts and scientific papers from the late 1960s and early 1970s placed the worldwide population in a broad and alarming range, often citing figures as low as 5,000 to 10,000 individuals, though some estimates extended up to 25,000. The wide variance in these numbers reflects the lack of standardized, pan-Arctic research methodology.
The primary force driving the population decline was intense, unregulated human harvest across the Arctic range states. Following World War II, new technologies dramatically increased the efficiency of commercial and sport hunting. Hunters began using aircraft, icebreakers, and large motorized vessels to pursue the bears, which led to unsustainable rates of removal.
In some regions, such as Svalbard, annual harvests were taking hundreds of bears, often using indiscriminate methods like set guns that killed females and cubs non-selectively. This heavy exploitation severely depleted many local subpopulations, creating an urgent conservation crisis that prompted international attention. Recognition of this over-hunting as the major threat led to the push for coordinated action.
The Turning Point: International Conservation Efforts
The alarming state of the population in the early 1970s led to a landmark agreement that fundamentally changed the fate of the species. This culminated in the signing of the Agreement on the Conservation of Polar Bears in Oslo, Norway, on November 15, 1973. The multilateral treaty was signed by the five nations whose territories encompass the polar bear’s range: Canada, Denmark (representing Greenland), Norway, the United States, and Russia.
The Oslo Agreement established a legal framework for international management, transforming the polar bear from an unregulated resource into a protected species. Its most immediate and impactful provision was the prohibition of the taking of polar bears, with a few carefully managed exceptions. Specifically, the agreement banned the use of aircraft and large motorized vessels for hunting, which had been the primary drivers of the commercial and sport hunting boom.
The treaty committed the signatory nations to managing their polar bear populations using sound conservation practices based on the best available scientific data. While banning commercial exploitation, it allowed for the continuation of traditional subsistence harvest by local people, provided these harvests were strictly managed. Crucially, the agreement also established a commitment to coordinated scientific research and data sharing among the five countries. This shift from exploitation to protection and science-based management allowed many depleted subpopulations to begin recovery from the historical low.
Tracking the Trend: Current Population Status
The conservation success initiated by the 1973 agreement is evident in the species’ recovery from its historical low point. Today, the global population of polar bears is estimated to be approximately 22,000 to 31,000 individuals, with a widely accepted central estimate of around 26,000. This number represents a substantial increase from the low, uncertain estimates of the early 1970s.
Modern management does not treat the polar bear as a single, uniform population, but recognizes it as occurring in 19 relatively discrete management units, or subpopulations, across the Arctic. The global estimate is a composite figure, calculated by summing the individual estimates for these distinct units. This approach acknowledges the varying ecological conditions and population dynamics in different parts of the Arctic.
The accuracy of current population data is significantly improved due to advancements in scientific methodology. Researchers now utilize sophisticated techniques such as aerial surveys, satellite tracking, and genetic mark-recapture studies, which were unavailable in the 1970s. This robust data collection allows for more reliable assessments of subpopulation size and trend, contrasting sharply with the limited data available five decades ago.
While the population has recovered from the threat of over-hunting, the management focus has shifted to a new challenge. The primary threat to the species’ long-term survival is now the loss of sea ice habitat driven by climate change. This environmental pressure dictates current conservation efforts, ensuring that while the numbers are higher than the 1970s low, the species remains a focus of international concern.