Boulder confirms first North American river otter sighting in a century
Caught on camera, a carnivore more common in a bygone era
An endangered North American river otter is photographed dining on a white sucker fish on March 7 along Boulder Creek east of downtown Boulder. The photos taken by a motion-activated wildlife surveillance camera offer the first documented sighting of the other in Boulder in about 100 years, city wildlife officials said. (Boulder Open Space and Mountain Parks)
A motion-activated wildlife surveillance camera has captured what one expert calls the first documented sighting of a North American river otter in Boulder in about 100 years.
"I was extremely surprised," said Christian Nunes, a wildlife ecology technician for Boulder Open Space and Mountain Parks. "It's a species that is quite rare in Colorado."
A member of the same family as weasels, the North American river otter (Lontra canadensis) is classified as "endangered" by Colorado Parks and Wildlife, but that could soon change -- in the otters' favor.
But, first, about those pictures.
Nunes said the camera was set up Feb. 1 along Boulder Creek, east of the city's developed core, near a beaver
An endangered North American river otter is photographed dining on a white sucker fish on March 7 along Boulder Creek east of downtown Boulder. The photos taken by a motion-activated wildlife surveillance camera offer the first documented sighting of the other in Boulder in about 100 years, city wildlife officials said. (Boulder Open Space and Mountain Parks)
The camera was equipped, Nunes said, with an infrared flash, which emits a blinking red light, rather than a conventional flash effect.
Nunes said the camera so far has captured an otter twice, both times at night -- fittingly, for this nocturnal animal. The first occasion was Feb. 26, and the second was March 7. It is images from the March 7 sighting, in which the animal was enjoying a meal of freshly caught white sucker, that the city has made available.
"It actually sat in front of the camera for several more minutes, sitting there munching on the fishtail," Nunes said. "Kinda cute."
Driven out
Once more easily found along Colorado's Front Range, the northern river otter largely had been extirpated -- driven to a localized extinction -- by the late 1800s or early 1900s, through hunting and mining pollution, Nunes said.
However, Colorado Parks and Wildlife launched an otter reintroduction program in the 1970s, restoring populations in several river drainages, including the Upper Colorado, the Dolores and the upper South Platte rivers.
Eric Odell, a state Parks and Wildlife species conservation program manager for carnivores, said the reintroduction was more focused -- and, apparently, more successful -- on the state's Western Slope.
A survey of the otters' numbers in the state in 2002 resulted in its status being upgraded from endangered to threatened. That is a status it shares among Colorado mammals with the Preble's meadow jumping mouse.
"We don't really have population estimates (for otters) anywhere in the state," Odell said. "But they certainly didn't take on the Front Range as well as they did on the Western Slope. They are pretty well-distributed on the river drainages on the Western Slope."
Odell added that his office gets many undocumented otter reports from the Front Range, "but they turn out to be muskrat, mink or beaver." To see a confirmed report of a river otter on the Front Range, he said, "is pretty exciting."
'Starting to spread out'
Parks and Wildlife is planning the first state survey of river otters since 2002 on the Western Slope later this year -- water levels and flows permitting, Odell said.
Depending on the results, Odell said, the state could further upgrade the animals' status, moving to "de-list" the river otter and take away its endangered status.
Nunes said he previously had heard anecdotal reports of otters in the Boulder area, including one from a friend who recently claimed to have tracked one in Boulder Canyon for six miles.
"They have been seen in Rocky Mountain National Park for a couple of decades, so they're doing well there, and they're starting to spread out," Nunes said. "We are extremely excited to have them back on our property."
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