Monochamus scutellatus
In 3 days ~60% in a week ~90%
Monochamus scutellatus, commonly known as the white-spotted sawyer or spruce sawyer or spruce bug or a hair-eater, is a common wood-boring beetle found throughout North America. It is a species native to North America. Adults are large-bodied and black, with very long antennae; in males, they can be up to twice the body length, but in females they are only slightly longer than body length. Both sexes have a white spot on the base of the wings, and may have white spots covering the wings. Both males and females also have a spine on the side of the prothorax. Most research done on M. scutellatus focuses on their relationship with burned forests and the logging industry, with interest also being shown in their mating behaviours.
Adults feed preferentially on members of the pine and spruce families for up to seven days after emerging between mid-June and mid-August. After mating, females chew small egg niches into dead or dying trees or logs, into which they deposit one egg each. Both sexes mate repeatedly with different partners, and females have been found to lay between 15 and 20 eggs on average per lifetime. Once the larvae hatch, they burrow into the phloem and... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Sequoia and Kings Canyon National Parks | 🇺🇸 United States | |
| 2 | Grand Teton National Park | 🇺🇸 United States | |
| 3 | Cape Breton Highlands National Park | 🇨🇦 Canada | |
| 4 | Glacier National Park | 🇺🇸 United States | |
| 5 | Banff National Park | 🇨🇦 Canada | |
| 6 | Voyageurs National Park | 🇺🇸 United States | |
| 7 | Wrangell-St. Elias National Park | 🇺🇸 United States | |
| 8 | Rocky Mountain National Park | 🇺🇸 United States | |
| 9 | Jasper National Park | 🇨🇦 Canada | |
| 10 | Isle Royale National Park | 🇺🇸 United States | |
| 11 | Yellowstone National Park | 🇺🇸 United States | |
| 12 | Kluane National Park | 🇨🇦 Canada | |
| 13 | Denali National Park | 🇺🇸 United States | |
| 14 | Elk Island National Park | 🇨🇦 Canada | |
| 15 | Acadia National Park | 🇺🇸 United States | |
| 16 | Yosemite National Park | 🇺🇸 United States | |
| 17 | Riding Mountain National Park | 🇨🇦 Canada | |
| 18 | Olympic National Park | 🇺🇸 United States | |
| 19 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 20 | Grand Canyon National Park | 🇺🇸 United States | |
| 21 | Great Bear Rainforest | 🇨🇦 Canada | |
| 22 | Shenandoah National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Calgary | 🇨🇦 Canada | |
| 2 | Montreal | 🇨🇦 Canada | |
| 3 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 4 | Toronto | 🇨🇦 Canada |
Possible
About 20% of wildlife watchers report a White-Spotted Sawyer sighting in Isle Royale National Park on a given day, based on 15 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 12th most-seen of the 48 insects we can rate there. Over three days the chance rises to about 60%, and over a week to about 90%, if each day is a fresh chance.
Between noon and 3 pm
Across all the parks we cover, that three-hour window holds the most White-Spotted Sawyer sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
10th of 22
Of the 22 parks where we can rate White-Spotted Sawyer sightings, Isle Royale National Park ranks 10th at about 20%. The best odds are in Sequoia and Kings Canyon National Parks (United States, about 40%), Grand Teton National Park (United States, about 30%) and Cape Breton Highlands National Park (Canada, about 30%).
GBIF citizen-science records
It is estimated from how often the White-Spotted Sawyer is recorded against all the insects logged in Isle Royale National Park (15 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
