Conservation

Commercial whaling has a long and devastating history that nearly drove several whale species to extinction. While indigenous peoples have hunted whales sustainably for thousands of years, the industrialization of whaling in the 19th and 20th centuries transformed it into a global enterprise of mass slaughter that marine ecosystems are still recovering from today. Early commercial whaling focused on species that were slow-moving, floated when killed, and lived close to shore. Right whales earned their name because whalers considered them the right whale to hunt, as they met all these criteria and yielded large quantities of oil and baleen. By the late 19th century, right whale populations in the North Atlantic had been so severely depleted that the industry shifted its focus to other species. The invention of the explosive harpoon gun in the 1860s and the development of steam-powered whale catchers in the late 19th century transformed whaling into an industrial operation capable of targeting the faster, larger rorqual whales that had previously been uncatchable. Blue whales, fin whales, sei whales, and humpback whales were hunted in enormous numbers, particularly in the Southern Ocean around Antarctica. Factory ships capable of processing whales at sea allowed whaling fleets to operate far from shore for months at a time. The scale of 20th-century whaling was staggering. During the peak decades of the 1920s through the 1960s, tens of thousands of whales were killed each year. An estimated 360,000 blue whales were killed in the Southern Hemisphere during the 20th century, reducing the population from perhaps 250,000 to fewer than 400 individuals by the mid-1960s. Humpback whale populations were similarly devastated, with over 200,000 killed in the Southern Hemisphere alone. Sperm whales were also heavily targeted for the spermaceti oil in their massive heads, which was used in lamps, lubricants, and cosmetics. The whaling industry followed a predictable pattern of serial depletion, hunting the most profitable species until it became commercially unviable, then switching to the next most valuable target. This cascading exploitation moved from right whales to larger rorquals and finally to smaller species like minke whales as bigger species became too scarce to hunt profitably. The ecological consequences extended far beyond the whales themselves: the removal of millions of whales disrupted nutrient cycling, altered predator-prey dynamics, and changed the structure of marine food webs in ways that scientists are still working to understand.

The International Whaling Commission (IWC), established in 1946, was originally created to regulate the whaling industry and ensure its sustainability. However, for decades the IWC failed to prevent overharvesting, setting catch quotas that were consistently too high to allow whale populations to recover. It was not until mounting scientific evidence of catastrophic population declines combined with growing public concern for whale welfare that the IWC took decisive action. In 1982, the IWC voted to implement a moratorium on all commercial whaling, which took effect in 1986. This moratorium remains the single most important international conservation measure ever enacted for whales. Under the moratorium, member nations agreed to cease all commercial whaling, though exceptions were allowed for aboriginal subsistence whaling by indigenous communities and for scientific research whaling. The moratorium has been controversial since its inception. Japan continued whaling under the scientific research exception for decades, killing hundreds of minke whales and other species each year in the Southern Ocean and North Pacific under its JARPA and JARPA II research programs. In 2014, the International Court of Justice ruled that Japan's Antarctic whaling program was not genuinely scientific and ordered it to cease. Japan subsequently withdrew from the IWC in 2019 and resumed commercial whaling in its own territorial waters and exclusive economic zone, though at significantly lower levels than its former research whaling. Norway lodged a formal objection to the moratorium and has continued commercial whaling of minke whales in the North Atlantic throughout the moratorium period. Iceland also resumed commercial whaling in 2006 after a brief hiatus, targeting minke and fin whales, though in 2024 Iceland announced significant restrictions on its whaling operations due to declining domestic demand and international pressure. Alongside the IWC moratorium, numerous national and international laws provide additional protection for whales. The U.S. Marine Mammal Protection Act (1972) and Endangered Species Act (1973) prohibit the harassment, hunting, or killing of whales in U.S. waters. The European Union bans all whaling by member states. CITES (the Convention on International Trade in Endangered Species) regulates international trade in whale products. The IWC has also designated the Southern Ocean and the Indian Ocean as whale sanctuaries, where commercial whaling is permanently prohibited. These protections have produced measurable results. Humpback whale populations in several ocean basins have recovered to the point where they have been removed from endangered species lists. Eastern North Pacific gray whales have recovered to approximately their pre-whaling population size. However, recovery is far from universal: North Atlantic right whales remain critically endangered, and blue whale populations are still a fraction of their historical abundance.

While the end of large-scale commercial whaling removed the greatest historical threat to whale populations, modern whales face a range of human-caused dangers that continue to kill thousands of individuals each year. Among the most significant of these threats are collisions with ships and entanglement in fishing gear. Ship strikes are a leading cause of death for several whale species, particularly those that inhabit busy coastal shipping lanes. An estimated 20,000 whales are killed by vessel collisions worldwide each year, though the true number is likely higher because many struck whales sink and are never recovered. Large container ships, tankers, and cruise ships traveling at speeds above 10 knots pose the greatest risk, as whales may not be able to detect or avoid these fast-moving vessels. The probability of a lethal strike increases dramatically with vessel speed: ships traveling above 15 knots kill whales in roughly 80 percent of collisions, while speeds below 10 knots reduce mortality to under 20 percent. The species most vulnerable to ship strikes is the critically endangered North Atlantic right whale, with fewer than 350 individuals remaining. Right whales feed at the surface and are slow-moving, making them particularly susceptible to collisions in the busy shipping lanes off the northeastern United States and eastern Canada. Ship strikes are the leading identified cause of death for this species, and losing even a few individuals per year can push the population closer to extinction. To reduce this risk, the U.S. National Oceanic and Atmospheric Administration (NOAA) has implemented seasonal speed restrictions for vessels in right whale critical habitat areas, requiring ships over 65 feet to slow to 10 knots or less. Entanglement in fishing gear is an equally devastating threat. Whales can become entangled in gillnets, lobster pot lines, crab trap ropes, and other fishing equipment, resulting in drowning, starvation, severe lacerations, infection, or exhaustion as the whale drags heavy gear through the water for weeks or months. Studies of humpback whales and right whales have found that over 80 percent of North Atlantic right whales and more than 50 percent of humpback whales show scarring from at least one entanglement event during their lifetimes. Efforts to reduce entanglement include the development of ropeless fishing gear (which uses acoustic releases or timed releases to retrieve traps without vertical lines), weak-link technology that allows whales to break free more easily, seasonal fishing closures in critical whale areas, and disentanglement teams that respond to reports of entangled whales. These conservation measures represent ongoing efforts to balance the needs of fishing communities with the survival of endangered whale populations.

Climate change and ocean noise pollution represent two of the most pervasive and difficult-to-address threats facing whale populations in the 21st century. Unlike the relatively straightforward solution of banning whaling, these threats are deeply intertwined with global economic systems and require coordinated international action to mitigate. Climate change is fundamentally reshaping the marine environments that whales depend on. Rising ocean temperatures are altering the distribution and abundance of key prey species, particularly krill and small schooling fish. In the Southern Ocean, warming waters and declining sea ice have contributed to a significant reduction in Antarctic krill populations, directly affecting the feeding success of blue whales, fin whales, humpback whales, and minke whales that depend on these waters for summer feeding. In the North Atlantic, warming sea surface temperatures have shifted the distribution of copepods, the primary prey of North Atlantic right whales, pushing them into Canadian waters where protective regulations are less established. Arctic whale species face particularly dramatic habitat changes. Rapidly diminishing sea ice is transforming the environment of bowhead whales, beluga whales, and narwhals, which have evolved over millions of years to thrive in ice-covered waters. As ice retreats, these species face increased competition from temperate species moving northward, greater exposure to shipping traffic as new sea routes open, and changes in the prey communities they depend on. Ocean acidification, another consequence of rising atmospheric carbon dioxide, threatens to disrupt the entire marine food chain by impairing the ability of shell-forming organisms to build their skeletons. Ocean noise pollution has increased dramatically over the past century as global shipping traffic, offshore energy development, and military activities have intensified. Ambient noise levels in many ocean regions have doubled roughly every decade since the 1960s. For whales that depend on sound for communication, navigation, finding food, and locating mates, this rising tide of noise is a serious problem. Chronic noise exposure has been shown to cause elevated stress hormone levels, disrupted feeding and breeding behavior, reduced communication range, and displacement from important habitats. Military sonar exercises have been directly linked to mass strandings and deaths of beaked whales and other sensitive species. Seismic surveys used in oil and gas exploration produce intense, repeated sound pulses that can travel hundreds of miles and have been shown to reduce catches of commercial fish species by up to 80 percent in survey areas, suggesting severe impacts on marine life including whales. Conservation responses include vessel speed reductions, shipping lane adjustments, seasonal restrictions on seismic surveys, and the development of quieter ship technologies.

Despite the many ongoing threats to whale populations, the story of whale conservation includes several remarkable success stories that demonstrate the resilience of these animals when protection measures are effective. These recoveries provide both hope and practical lessons for future conservation efforts. The recovery of humpback whales is perhaps the most celebrated conservation success. Hunted to near-extinction by the mid-20th century, with global populations reduced to perhaps 10,000 individuals, humpback whales have rebounded dramatically since the whaling moratorium. Today, the global humpback population is estimated at over 80,000 and continues to grow. In 2016, nine of the fourteen distinct population segments of humpback whales were removed from the U.S. Endangered Species List, a testament to decades of protection and the species' strong reproductive capacity. Eastern North Pacific gray whales have similarly recovered from the brink. Once reduced to fewer than 2,000 individuals by commercial whaling, this population has rebounded to approximately 27,000 animals, roughly matching pre-whaling estimates. This recovery is considered one of the most complete for any large whale species and was made possible by the protection of both feeding grounds in the Arctic and calving lagoons in Baja California, Mexico. The recovery of Southern Hemisphere blue whales, while much slower, is also underway. Antarctic blue whale numbers, which were reduced from approximately 250,000 to fewer than 400 by industrial whaling, are now estimated at several thousand and growing at roughly 7 percent per year. While still a small fraction of their historical population, this growth rate suggests that blue whales are on a trajectory toward meaningful recovery, though full recovery will take many decades given their slow reproductive rate. Not all whale populations are recovering, however, and some face an uncertain future. The North Atlantic right whale remains critically endangered with fewer than 350 individuals and has been declining since 2010 due to a combination of ship strikes, fishing gear entanglement, low calving rates, and shifting prey distribution linked to climate change. The western North Pacific gray whale population is also critically endangered with roughly 300 individuals. The vaquita, a small porpoise in the Gulf of California, is the world's most endangered cetacean with fewer than 10 individuals remaining. Looking ahead, effective whale conservation will require addressing the complex, interconnected threats of climate change, ocean noise, plastic pollution, chemical contamination, and ongoing illegal whaling. Marine protected areas, ecosystem-based management approaches, international cooperation, and continued scientific research will all be essential. The whales' ability to recover from near-extinction when given the chance remains one of the most powerful arguments for ambitious conservation action, demonstrating that it is never too late to make a difference for even the most imperiled species.