Swarm of earthquakes one for the history books

When the dishes and windows rattled and the house shook for 10 to 15 seconds my first thought was a major train derailment. But then I realized it might have been an earthquake. 

An earthquake in North Idaho! Sure enough, the USGS reported a quake within a few minutes on their website. A 4.1 magnitude earthquake 22 km southeast of Sandpoint (vicinity of the Green Monarchs) at 7:32 p.m. on Thursday, April 23. 

Then a swarm of five earthquakes happened over the next 17 hours, all in the vicinity of Lake Pend Oreille. The USGS revised the data by Saturday to reflect new magnitudes, including reducing the initial earthquake to magnitude 3.7. Revisions often are made as more data is gathered from seismograph stations around the world. 

Six earthquakes happened within 17 hours (dots south to north): Thursday, April 23 at 7:46 p.m.; Thursday at 7:32 p.m.; Thursday at 8:22 p.m.; Thursday at 10:43 p.m.; Friday, April 24 at 1:28 a.m.; and Friday at 11:39 p.m. (Source: USGS)

The second and third earthquakes were smaller and less likely to be felt. The second earthquake was magnitude 1.9 at 7:46 p.m. and the third was a magnitude 1.8 at 8:22 p.m.

The fourth quake at 10:43 p.m. was originally classified as a magnitude 4.2 but later downgraded to magnitude 3.9. The fifth quake registered a magnitude of 3.3 at 1:28 a.m. on April 24 and the sixth quake registered a magnitude of 2.7 at 11:39 a.m. The larger earthquakes were felt by people across North Idaho and into northeastern Washington and northwest Montana. 

Did you feel the earthquake?

Earthquakes are uncommon in North Idaho so when the windows rattled and the house shook, it took a minute register what happened. I hadn't felt an earthquake since living in Anchorage, Alaska.

Within minutes, the USGS reported a magnitude 4.1 earthquake centered 22 km southeast of Sandpoint, Idaho in the vicinity of the Green Monarchs at 7:32 p.m.

To view the shake map (the intensity of where the earthquake was felt), go to http://earthquake.usgs.gov/earthquakes/eventpage/us200028q3#impact_shakemap

I'm excited to have felt an earthquake in North Idaho!

Mink: the semiaquatic weasel

When I see a small mammal swimming in the water, there are only a few choices-- at least I thought. One animal had me stumped. 

The animal wasn’t a beaver because only a beaver’s wedge-shaped head shows when swimming. The tail wasn’t narrow and snaking behind like that of a muskrat. The animal didn’t have the sleek fur coat of a river otter and otters swim with very little of their back exposed. 

Mink have silky brown to black fur with a white chin patch. They average two feet in length but one-third of that is their tail

What was left in the mammal book for an animal that size? An American mink. 

Spring time means tick time

No longer do I squeal “Get it off me!” when I find a tick crawling on me. I’ve come to terms with ticks and can flick them off with my fingers--a milestone I never thought would happen. On one spring hike, I picked off two dozen ticks by the time I returned to the trailhead and felt as if more were crawling all over me. 

Rocky Mountain wood ticks (male on left, female on right)

In North Idaho, the Rocky Mountain wood tick is the main tick you’ll find on yourself. Females have a gray colored dorsal shield (area behind their head) and a brown body while males are mottled brown and gray.

Millipedes don’t really have 1,000 legs

While sweeping the garage last fall, I came across small carcasses that were c-shaped, hollow, white and smaller than a dime. I hadn’t seen any creature around that could have made them until last week when I moved the compost barrel. 

Beneath the barrel were several small (one to two inches) black creatures with lots of legs that I had never seen before--millipedes. I probably hadn’t seen them before because they prefer moist, dark places like under compost.

Millipedes move by coordinating their legs so their body moves in a wave-like motion. All the legs on one body segment move forward together.

Some were curled up in the exact shape of the carcasses that were in the garage. I found out they tend to curl up when threatened to protect themselves. If I had touched one it may have released a toxic chemical thinking I was a predator. 

Pondering Lake Pend Oreille

There is something about large bodies of water that I cannot describe. I found myself gazing in wonder out over Lake Pend Oreille on a recent hike at Mineral Point. Is it the vastness? The unknown?

Mineral Point only offered a glimpse of the 111 miles of shoreline that twist between the Cabinet, Selkirk and Coeur d’Alene Mountains.

The U.S. Navy tested submarines in Lake Pend Oreille and established Farragut Naval Training Station during WWII at the south end of the lake

Lake Pend Oreille is huge compared to the mountain lakes I’m familiar with such as Roman Nose Lakes. At 65 miles long and a surface area of 148 square miles, Lake Pend Oreille is the largest lake in Idaho.