Conservation efforts since 1993 have saved up to 32 bird and 16 mammal species from extinction, according to a study published in Conservation Letters.
A large cohort of scientists led by Newcastle University used expert elicitation (scientific consensus to form an educated ‘guess’) to estimate how many species of birds and mammals would not exist without conservation efforts. Looking closely at efforts by the Convention on Biological Diversity from 1993 to 2020, the authors report that 21 to 32 bird and 7 to 16 mammal species have been saved.
The Convention of Biological Diversity is a global treaty signed by 192 nations – every nation in the world except the United States – aimed at conserving biodiversity and increasing sustainable development. Since its introduction, various methods of protecting natural species have been used to slow declining population numbers. Of those, the most successful at preventing bird extinctions was management of invasive species, whilst the best methods of preventing mammal extinctions appeared to be legal protections against hunting and area management of habitats.
Among the species that were saved from the brink was the Iberian lynx, a wild cat species native to southwestern Europe. Down to just 100 individuals, conservation measures saved the species by re-introducing them to improved habitats with more prey availability. The World Wide Fund for Nature (WWF) now estimates Iberian lynx populations to sit above 400. Many more species showed a high degree of certainty that conservation efforts saved them, including red wolves and Spix's macaws.
However, it has not all been a success story. During that period, 10 bird and 5 mammal species went extinct, serving as a stark reminder there is more work to be done. Among these were the Brazillian cryptic treehunter, which was last spotted in 2007 and is now formally classified as extinct, as well as the Saudi gazelle, which was formally declared extinct in 2008.
Despite the losses, without the global efforts to protect wildlife from destruction, the total number of extinct species could have been up to four times that number. Agriculture and hunting are among the largest culprits for the decline in animal species, with habitat destruction, invasive species, and climate change also making the ranks of most harmful factors.
Many of these species saved from extinction still remain endangered, and the authors say increased awareness and action are needed to spare more in the future.
“Given the ongoing scale and projected growth in pressures on biodiversity, considerably greater efforts are needed to prevent the extinction and improve the status of the 6,811 species currently assessed as critically endangered on the Red List," write Friederike Bolam et. al in the study.
The authors state there is a degree of uncertainty in their estimations and the ranges provided are approximations. They also suggest the costs of conservation endeavors compared to their successes should be monitored to help streamline efforts.
“Quantifying these investments and comparing them with investments for species that did go extinct, should be prioritised for future research,” write the authors.
The Zoological Society of London's Living Planet Report 2020 states that animal populations have declined by 68 percent since 1970. The report emphasizes that conservation efforts do work but that more sustainable practices in general are needed to curb biodiversity loss.