Commercial whaling decimated global whale populations, causing the extirpation of some populations and leaving others on the precipice of extinction. At least 300,000 humpback whales were killed between the late 1700s and mid-1900s worldwide. Numbers of western South Atlantic humpback whales plummeted from nearly 27,000 in 1830 to only 450 by the mid-1950s. A study recently published in Royal Society Open Science, however, indicates that protections afforded humpback whales over the past half century have helped reverse the decline. The study authors predict that this population may be fully recovered by 2030 but caution that ongoing monitoring is necessary to evaluate how these whales respond to modern threats, particularly entanglement in fishing gear, and to climate-driven impacts to their habitat.