New research tracking fifteen narwhals over four years has revealed that they like to hang out near glaciers that are stable and do not have many calving events.
To better understand what glacier features narwhals prefer, Laidre and her colleagues used data from 15 narwhals outfitted with recorders that tracked each animal’s movements over four years in the 1990s and 2000s in Greenland’s Melville Bay, where narwhals congregate in summer. They combined this data with information about glaciers in Melville Bay over the same time period.
The researchers examined how narwhals behaved at the glaciers and collected information about each glacier’s physical properties to create models of narwhal behavior and tease out the animals’ preferences. “Narwhals like slow-moving, big walls of ice where conditions are still and serene instead of a lot of runoff and disturbance,” Laidre said.
The researchers don’t know why the narwhals prefer these glaciers. They think the freshwater could shock small marine critters that are food for fish, which narwhals eat. Narwhals are also close relatives of beluga whales, which also seek out freshwater in summer to shed their skin, and it is possible there is something similar going on at the glacier front, Laidre said.
This is fascinating research. What is especially refreshing about it is that the press release makes no mention of global warming, a omission that is proper but increasingly rare in the politicized science community.