This story is literally from my back yard. It illustrates how easy it is to blame more or less anything on global warming, and how uncritically such claims are swallowed by the press. If it fits the agenda, it is fit to print.
On May 13, the Minnesota Zoo–which is, I believe, the only state-owned zoo in the U.S.–released a statement to the effect that its last two remaining musk oxen were being euthanized. At one time, the zoo had an actual herd of musk oxen, but those days obviously are gone:
Starting with two males from Calgary, Canada, the Zoo eventually acquired two females from Winnipeg and the herd began to grow. Since 1980, 65 musk ox calves were born at the Zoo – one of the most successful records of any North American facility.
About 10 years ago though, keepers started noticing changes in the herd. The increased summer heat and humidity had begun affecting the oxen – a species native to the arctic tundra. It seems even Minnesota has now become too far south for this species to thrive.
As summers have continued to get warmer, more heat-related issues could be spotted and keepers like Cindy could pick up on even the most subtle changes.
The zoo made a decision some time ago to get out of the musk oxen business. The formerly robust herd was down to two elderly individuals:
With the changes noted, the Zoo made the decision to stop breeding musk oxen about a decade ago and not acquire any new herd members. Over those next 10 years, the herd became smaller and older until only two senior females remained.
Both females had a number of age-related challenges that became compounded by the spring and summer heat.
The decision to do away with the last two old, sick musk oxen was no doubt a good one. But did it really have anything to do with global warming? The New York Post bought the claim uncritically:
Since 2000, Minnesota has racked up many of its warmest days on record — with the average temperature having risen by 2 degrees since 100 years ago, according to the National Oceanic and Atmospheric Administration.
Though musk ox is native to the arctic tundra, the Minnesota Zoo had long been home to the herd thanks to the state’s historically chilly climate during much of the year. However, the rising average summer temperatures have proven detrimental to the cold-weather creatures.
This is NOAA’s page on Minnesota. It does indeed allege that “[t]emperatures in Minnesota have increased more than 2°F since the beginning of the 20th century.” Whether this is true is hard to say, because NOAA has made so many adjustments to historic temperature records. But what supposedly harmed the musk oxen were the hot days of summer. Have they increased? NOAA says they have not.
This warming has been concentrated in the winter while summers have not warmed as much. The summer warming has been mostly an increase in nighttime temperatures, with the coolest nights of summer becoming warmer. By contrast, summer daytime high temperatures have increased very little.
In fact, there have been fewer “hot” days–i.e., days over 90 degrees F–in recent Minnesota summers:
NOAA acknowledges: “Since 1990, Minnesota has experienced a below average number of hot days.”
It sounds as though the Minnesota Zoo made a decision some time ago to phase out its musk oxen exhibit. I have no idea why. It could possibly be true that the state’s climate turned out to be insalubrious for these animals, although the zoo’s own account suggests that the herd was thriving until the recent past. The zoo’s suggestion that weather changes started damaging the musk oxen “about ten years ago” finds no support in the weather records. Whatever caused the zoo to euthanize the last old, sick survivors, it was not global warming.
On a happy note, the musk oxen went out with a bang. This February in Minnesota was an epically cold month. In fact, “February 6-15, 2021 brought the 5th coldest ever 10-day February period of weather (mean temperature -5.4°F) to the Twin Cities (back to 1873).” So maybe the musk oxen expired dreaming of the tundra.