Still more climate fraud

First ever worldwide census analysis of caribou/reindeer numbers reveals dramatic decline

Caribou and reindeer numbers worldwide have plunged almost 60% in the last three decades.
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The dramatic changes caused by global warming that happen in the Arctic and which impact on the herds include; earlier spring green ups that now occur before migrating herds arrive north and which deprive mothers and calves of quality feeding; warmer summers that cause more intense insect activity harassing animals and affecting their feeding; the impact of more freezing rain during winter on the lichens that animals feed on during the colder months.

First question: If this is the FIRST ever worldwide census, exactly how would we know that numbers have plunged almost 60% in the last three decades?

Second question: Where's the evidence here of  slight warmth causing massive caribou declines? - Caribou in ANWR

Both the Porcupine and 'Central Arctic Herds are biologically healthy. After a long period of stability at around 100,000 animals, the Porcupine Herd began to grow steadily during the late 1970s and 1980s and reached 180,000 animals by 1989. The herd then decreased during a series of severe winters and was down to 160,000 in 1992. In 2002, the Porcupine Herd numbered 123,000, but the caribou were in excellent physiological condition.

The Central Arctic Herd also increased during the 1970s and 1980s from 6,000 in 1978 to 23,400 in 1982. Rapid growth stopped in the late 1980s, however, and the herd now appears stable at around 32,000 animals. Relatively low calf production and survival in recent years may result from severe winter weather which has also depleted moose and Dall sheep populations in the central arctic area. It is also possible that the Central Arctic Herd is approaching range carrying capacity.