Wildlife & nature
Species recovery, rescue and anti-poaching. Real interventions, each with its sources: what worked, what didn't, and why.
5 worked2 mixed2 didn't work
What worked
- WorkedWildlife & nature
Wildlife overpasses and underpasses on Banff’s Trans-Canada Highway
ChallengeA busy highway through a national park was killing elk, deer and bears and cutting habitat in two.
Parks Canada fenced the highway through Banff and built 44 overpasses and underpasses for animals.
>80%fewer wildlife-vehicle collisions after fencing and crossingsQuasi-experimentalRead case - WorkedWildlife & nature
Capturing every wild condor to save the species: California condor recovery
ChallengeOnly 22 California condors survived, and lead from hunters’ bullets kept killing wild birds.
All remaining wild condors were captured, bred in zoos, released and treated for lead poisoning.
566condors alive at end of 2024, from 22 in the early 1980sObservationalRead case - WorkedWildlife & nature
The Treasure oil spill penguin rescue in Cape Town
ChallengeA sinking ore carrier leaked fuel oil next to the world’s largest African penguin colonies.
Volunteers and SANCCOB cleaned about 20,000 oiled African penguins and moved 19,500 more out of harm’s way.
90%+of oiled penguins rehabilitated and releasedObservationalRead case - WorkedWildlife & nature
Zero rhino poaching years in Nepal
ChallengePoachers killing greater one-horned rhinos for their horns threatened Nepal’s small population.
Nepal combined army patrols, park staff, police intelligence and local communities to stop rhino poaching.
752rhinos counted in 2021, up from 534 in 2011ObservationalRead case - WorkedWildlife & nature
Bringing wolves back to Yellowstone National Park
ChallengeWolves had been wiped out in Yellowstone, leaving elk without their main predator.
US agencies released 31 Canadian wolves into Yellowstone in 1995–96, decades after wolves were wiped out.
108wolves in Yellowstone at end of 2024, from 31 releasedObservationalRead case
Mixed results
- MixedWildlife & nature
China’s ban on its domestic ivory trade
ChallengeChina’s legal ivory market gave cover to illegal ivory and fuelled elephant poaching in Africa.
China closed its legal ivory carving and retail trade, shutting 172 factories and shops by the end of 2017.
8%of Chinese consumers intending to buy ivory in 2020 after being reminded of the ban (18% in 2017)ObservationalRead case - MixedWildlife & nature
Namibia’s communal conservancies
ChallengeWildlife on communal land had been heavily poached, and local people gained nothing from it.
Namibia gave rural communities legal rights to manage and earn money from wildlife on communal land.
86communal conservancies, covering almost 20% of NamibiaObservationalRead case
What didn't work
- Didn't workWildlife & nature
Mexico’s gillnet bans to save the vaquita porpoise
ChallengeThe vaquita, the world’s smallest porpoise, was drowning in illegal gillnets set for totoaba fish.
Mexico banned gillnets in the upper Gulf of California and later set a guarded zero-tolerance zone.
6–8vaquitas seen in a May 2024 survey, a minimum count (59 estimated in 2015)ObservationalRead case - Didn't workWildlife & nature
Australia’s introduction of cane toads to control beetles
ChallengeCane beetle larvae were damaging Queensland’s sugar cane crops.
Queensland’s sugar research bureau imported cane toads in 1935 to eat beetles damaging sugar cane.
102toads imported in 1935, now spread across northern AustraliaObservationalRead case