Conservation-themed images, a lone rhino, a rare porpoise, bring endangered-species questions to the Bing homepage, and the Endangered Animals quiz drew enormous search interest. The questions revolve around the rarest species and the system used to rank them.
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The Red List system
The IUCN Red List is the global register of species' conservation status, running from Least Concern through Vulnerable and Endangered to Critically Endangered, Extinct in the Wild and Extinct. 'Which organisation maintains the endangered species list' points to the IUCN.
The rarest of the rare
The vaquita, a small porpoise in Mexico's Gulf of California, is the world's rarest marine mammal, with only a handful of individuals left. The Javan rhino and Amur leopard rank among the rarest large land animals, each numbering in the dozens to low hundreds.
A comeback story
The giant panda is the quiz's favourite good-news answer: decades of conservation in China saw it downlisted from Endangered to Vulnerable in 2016. Questions about what pandas eat, overwhelmingly bamboo, often ride alongside.
Causes and answers
Habitat loss, poaching and climate pressure are the standard 'main threat' options. For any population-number question, figures change, so a quick search of the species plus 'population' brings the current estimate.
Frequently Asked Questions
What is the rarest marine mammal?
The vaquita, a small porpoise found only in Mexico's Gulf of California, with only a handful of individuals remaining.
What is the IUCN Red List?
The global register of species' conservation status, from Least Concern through Endangered to Extinct, the standard reference quizzes cite.
Are giant pandas still endangered?
They were downlisted to Vulnerable in 2016 after decades of conservation in China, the quiz's favourite comeback story.