The new Alaska Department of Fish and Game census puts the herd’s population at 218,000, which is the highest since the state began monitoring the herd in the 1970s.
The Porcupine Herd received national attention this winter because its calving grounds are often on the coastal plain of the Arctic National Wildlife Refuge, including the part of the refuge Congress and President Donald Trump opened to oil and gas leases last month as part of the Republican tax overhaul bill. Opponents of oil and gas drilling in the refuge often argue that oil exploration and extraction would hurt the herd and the people who rely on the herd for food.
The Porcupine Herd has the largest land migration in the world, according to the Department of Fish and Game. The herd migrates over a Kansas-size area in northeast Alaska and Canada’s Yukon and Northwest territories.
Caribou herds are known for dramatic population swings. Populations can collapse suddenly when herds overgraze available food. The Porcupine Herd was estimated to be as large as 178,000 animals at its last peak in 1989 and dropped to a low of 123,000 in 2001 before climbing to its current high.
The Porcupine Herd has grown as the Western Arctic Herd, in Northwest Alaska, has declined. The Western Arctic Herd was once unquestionably the largest herd in the state, with a population of 490,000 in 2003.But the herd dropped to 201,000 by the summer of 2016. The Western Arctic Herd was also photographed in the summer of 2017, but census numbers for that herd weren’t available Tuesday.