Key facts
- Bluefin tuna have returned in significant numbers to UK waters.
- WWF's Living Planet Report 2026 estimates global monitored wildlife populations have fallen by 73% since 1970.
- Conservation efforts, including reduced catch quotas and protected spawning grounds, are credited with the bluefin tuna's return.
- Wild tiger populations have increased by over 70% since 2010.
- Green sea turtles have moved from 'endangered' to 'least concern' status after 50 years of conservation.
- WWF estimates $7.3 trillion was spent on activities harming nature in 2023, compared to $220 billion on protection and restoration.
Bluefin tuna have returned in significant numbers to UK waters, a development highlighted in a new report by WWF as evidence that conservation efforts can be successful. The giant predatory fish had largely disappeared from British waters by the 1960s due to overfishing.
The WWF's Living Planet Report 2026 credits the bluefin tuna's recovery to international efforts, including reduced catch quotas, size limits, and protection of spawning grounds, supported by consumer and industry campaigns. Hannah Rudd, head of marine at the Angling Trust, described the population increase as close to an "explosion" and a "golden case study" for effective fisheries management.
However, the report also paints a stark picture of global biodiversity loss, estimating that monitored wildlife populations worldwide have fallen by an average of 73% since 1970. This figure, compiled by WWF in collaboration with the Zoological Society of London, tracks nearly 36,000 populations of almost 6,000 species. While about half of these populations are stable or growing, their gains are offset by losses elsewhere.
Other conservation successes cited include a more than 70% increase in wild tiger numbers globally, from around 3,200 in 2010 to about 5,700 in 2025. The green sea turtle has also seen its protection status downgraded from "endangered" to "least concern" after five decades of conservation work across approximately 80 countries. Elephant populations are reported as stable or growing in parts of southern Africa, partly due to new laws that grant local communities a share of tourism income generated by elephants.
Mike Barrett, chief scientific adviser at WWF-UK, emphasized that these successes stem from clear goals, credible plans, and belief in making a difference, describing it as "the science of hope" which requires action rather than passive wishful thinking. He noted that this is the first Living Planet report where the takeaway message is to focus on hope, stating that the window of opportunity to act is still open.
Despite these positive examples, the overall trend for nature remains critical. Dr. Katie Collins, a senior curator at the Natural History Museum in London, pointed out that the WWF's index focuses only on vertebrates, omitting crucial species like plants and insects that form the base of ecosystems. WWF argues that reversing the decline requires tackling the root causes, including destructive farming practices and the burning of fossil fuels, which drive climate change. The report estimates that in 2023, approximately $7.3 trillion was spent on activities harmful to nature, vastly outweighing the $220 billion allocated to protection and restoration.