The biggest threat to the integrity of environmental science is bad science, exaggeration and fear mongering. The recent hype about declining moose populations is just one more example of global warming advocates hijacking and denigrating ecological science. All organisms act locally, yet global warming advocates quickly characterize any local wildlife declines as the dastardly work of global warming.
In northeastern Minnesota, moose populations reached an historic high abundance of 8,840 in 2006, and then rapidly declined to 4,230 in 2012. Most recently in a 2013-2014 survey, estimates dropped to 2,760 moose. Cause for alarm? Perhaps. But moose are a species known to naturally exhibit booms and busts when their habitat can no longer sustain a rapidly growing population. Instead of deeper discussions on the ecological complexities, but reminiscent of the fearful headlines that “children will no longer know what snow is”, the National Wildlife Federation (NW) bellowed “People never forget seeing their first moose. But due in part to the effects of climate change, it could well be their last. Moose are being hurt by overheating, disease and tick infestation – all tied to warming temperatures.” And to magically save the moose, the NWF encourages you to sign their petition to the EPA to curb CO2 emissions, and for just $20 to $50 you can adopt a moose from the NWF. Presumably the $50 moose is in its prime and carries fewer ticks.
The Audubon Society similarly published Mysterious Moose Die-Offs Could be Linked to Global Warming and climate scientists like Michael Mann, who has hitched his scientific status to “dire predictions”, wrongly connect declining moose populations to rising CO2. There are so many reasons to be revolted by their fear mongering and its denigration of ecological science, it’s hard to know where to start. For instance, the greatest spike in moose mortality happens in March at the end of severe winters. Milder winters can be beneficial. While alarmists blame moose deaths on “global warming”, the rapid decline in northeastern Minnesota has happened in a region experiencing bouts of record breaking low temperatures. Nearby International Falls, MN broke its record January low of -37°F set in 2010, by dropping to -41°F in 2014, which followed December’s record setting 8 days with a temperature of less than -30°F. Averaging local temperatures is likely as useless as referring to the global temperature.
Furthermore moose die‑offs are not global. Adjacent habitat in southern Ontario, moose are stable or increasing. Estimates of moose populations have traditionally been based hunters’ harvest and in Scandinavia, the annual harvest was less than 10,000 in the early 1900s. After a century of global warming the moose population reached an all time high with annual harvests increasing 20‑fold to 200,000. Similarly in the 1900s, moose from British Columbia expanded into Alaska and multiplied as the climate warmed. In New England, moose were more abundant that deer when the Pilgrims arrived. But due to deforestation for farmland and overhunting, moose have been absent from Massachusetts and Vermont for 200 years. In 1901 less than 20 moose were believed to inhabit New Hampshire. But in contrast to fearful global warming theory and species range, since 1980 moose have migrated south from New Hampshire into Massachusetts and Connecticut, despite temperatures that average 4 to 6° F warmer.
Scandinavian biologists suspect the moose population may begin to decline, but their reasons illustrate the complex ecology. Increasing moose densities strain food supplies resulting in lower body mass, lower reproductive success, and lower resiliency. Moose thrive on vegetation common in regenerating forests that have been cleared by insect outbreaks, fires or logging. Scandinavia’s 20th century increased logging has now peaked and will decline, and so will moose lose habitat as closed forest canopies reclaim the landscape . Except in eastern Finland, depredation by wolves has been minimal, but wolf populations are now rebounding.
The best studied moose population exists just east of Minnesota’s northeast border on Isle Royale in Lake Superior and illustrates the boom and bust nature of moose populations. As moose populations globally expanded in the 1900s, they soon colonized Isle Royale around 1912 and rapidly grew to over 3000 by early 1930s. Rapid population growth diminished food supplies and a starvation crash happened in1934. Extensive forest fires in 1936 increased their preferred vegetation and feasting on young vegetation in a regenerating forest, the population rebounded until it peaked as it increasingly suffered from winter starvation. To add another factor governing moose population in the 1940s wolves colonized Isle Royale.
Virtually every college ecology text discusses the predator-prey interactions illustrated by the wolves and moose of Isle Royale. As observed elsewhere in the Great Lakes region, moose populations remained low until they began increasing in the 1950s. As seen in the diagram below, moose populations rose but also ebbed and flowed inversely with wolf populations. In contrast to suggestions that global warming is killing moose, during the rapid warming from the 80s to 90s, Isle Royale moose doubled their population, approaching a peak not observed since the 1930s, then suddenly crashing to just 500 in 1997. Moose have slowly rebounded since 2007 and are now at levels 50% higher than the 1950s.