Garter snakes most common snake in Idaho

Unlike southern Idaho, north Idaho is thankfully devoid of poisonous snakes. The snakes that do live in the forested region of the north are harmless to humans and the ones you’ll most likely encounter are garter snakes. 

Two types of garter snakes live in Boundary County--the common garter snake and the western terrestrial garter snake. Both have three cream to yellow stripes running down their length, with one dorsal (back) stripe and one on each side. The stripes on the western terrestrial garter snake can appear wavy because dark, pencil eraser-sized spots scattered over its back overlap the edges of the stripes.

Another way to tell the two snakes apart is the color between the stripes--the common garter snake is very dark to black while the western terrestrial garter snake is olive to greenish gray. Additionally, some common garter snakes have red spots on the sides of their bodies. 

Both survive on a wide variety of prey. They both prey on earthworms, slugs, leeches, frogs, fish and mice. The western terrestrial garter snake also preys on tadpoles, snails, lizards, insects and carrion (roadkill) while the common garter snake rounds out its diet with toads, salamanders, some birds and the occasional insect or spider. Young common garter snakes primarily eat earthworms until they’re large enough to attack more challenging prey. 

The garter snake’s habitat is as varied as its diet--anywhere associated with water, such as marshes, streams and ponds. They can also be found in open meadows and even swimming. Common garter snakes also venture into coniferous forests. The wide-range of habitats that garter snakes occupy, along with their varied diet makes it easy to understand why they are the most common snake in Idaho. Common garter snakes are also one of the most widely distributed reptiles in North America. 

Wetlands provide water, shelter and a large prey base for snakes 

Since snakes are reptiles, they can either lay eggs or bear live young. Most snakes in Idaho are egg layers but both garter snakes bear live young, typically between July and September. The western terrestrial garter snake bears four to nine young while the common garter snake averages 13 to 26 young but has been known to have up to 85 young! 

Birth isn’t the only time large quantities of snakes can be found together--snakes often group together during hibernation. Dozens to hundreds of garter snakes may congregate in hibernacula (winter dens) to spend the winter. Garter snakes often hibernate in crevices on south-facing rocky outcrops, which can include a natural rock wall in your yard. 

During sweltering summer afternoons, garter snakes take shelter under logs, boards, rocks, leaf piles, firewood piles and anywhere else that is cool. They need the sun to warm their cold-blooded bodies, but they also need to seek shelter on hot days so they don’t overheat. Besides, when they are basking in the sun they are vulnerable to predators like skunks, raccoons, bears, hawks, owls, magpies and crows. 

Even though garter snakes are not poisonous to people, they will emit a musky scent and/or fecal matter if they feel threatened by predators, including people. 

Note: Published in the Bonners Ferry Herald on July 26, 2012. 

Praying mantis captures food with quick reflexes, fatal grip

Insects range from beautiful butterflies to everyday ants to creepy spiders and everything in between. Praying mantids are in-between with their strange looks and fatal forelegs.

A praying mantis specimen

Mantids are not as common as ants, grasshoppers or spiders. Usually, you will accidentally find them. Praying mantids are typically green or brown and blend in well with their surroundings. 

Their remarkable camouflage allows them to sit and wait for prey and helps them avoid being prey. A mantis will remain motionless while waiting for prey to pass by. Sometimes, they will gently rock side to side as if swaying in a breeze. Mantids will eat moths, crickets, grasshoppers, flies and even each other. 

As it waits, the mantis holds its forelegs folded against its prothorax in preparation to snatch an insect. This pose suggests an attitude of prayer and is how the praying mantis received its name. 

A mantis can swivel its head 180 degrees, giving it a wide field of vision. Its two compound eyes and three single eyes between the two eyes allows it to gauge the distance of moving objects up to 60 feet away. 

If the insect is within range, the mantis will slowly swivel its head and prothorax in the insect’s direction and will then quickly snatch the insect with its spined forelegs. 

Spiny forelegs and triangular head characterize the praying mantis

Some mantids are fast enough to snatch a passing fly or flying insect out of the air. However, if an insect remains motionless, a mantis will not recognize it as prey and may walk past it or even over it without responding. 

Once the insect is in the mantid’s pincer-like grip, the mantis begins to devour the insect alive because its strong grip prevents the prey from escaping. 

When mantids are on the other end of the food chain, they have defensive strategies to survive. Birds, lizards, insectivorous mammals, bats and spiders eat mantids. To avoid predators, mantids can quickly run away, launch into flight or expose bright-colored markings. If those strategies don’t work and the predator approaches too closely, the mantis will immediately strike with its spined forelegs (even towards a curious person). 

If picked up, the mantis will bend its forelegs backwards over its prothorax and utilize its spines to ensure it is dropped or held more carefully. 

If the mantid is only being held by a mid- or hind-leg, it will sacrifice it to escape, just like western skinks do with their tails. The mantis can contract a special muscle at the base of its leg to release it while it pulls away. If the mantid is young, the leg will grow back. A mantid will not sacrifice its front legs because without front legs it cannot catch food. 

Mantids are one of those species that will eat their own kind. Female adults will eat other female’s young and in some subspecies, the female with eat the male before, during or after mating. 

The spiny forelegs and triangular head are the two identifying characteristics of the strange-looking praying mantis. If you find one and want a closer look, be careful of the spiny forelegs.

Note: Reprinted by request. Originally printed in the Bonners Ferry Herald on November 11, 2010.

Color can be deceiving when it comes to bears

After spotting a bear in the basin below Goat Mountain on the State Line, I pull out my binoculars to take a closer look. Even though the bear is black, I can’t assume it is a black bear since grizzly bears can be black and this is both grizzly and black bear country. I try to glimpse a profile view of its face, shoulders and rump as it wanders through the trees. These physical characteristics are the best means of identifying a bear from a distance. 

A black bear has a long, straight profile from its forehead to nose tip while a grizzly bear has a concave or dish-shaped profile from between its eyes to the end of its nose. These facial characteristics make a black bear’s face appear round and a grizzly bear’s face appear broad. 

A family of black bears identified by the straight-profile face of the mother bear

When looking at the shoulders, grizzly bears have a distinctive shoulder hump created by their massive shoulder muscles used for digging. The shoulder hump is the highest point on a grizzly bear when it is standing on all fours. Black bears lack a shoulder hump so their highest point while on all fours is either their rump or middle of their back. 

The distinctive shoulder hump of a grizzly bear can be seen from a distance

If the bear is closer, another identifying characteristic is the ears. Grizzly bears have smaller, rounder ears while black bears have larger, longer, more pointed ears. 

Black bears have larger, longer, more pointed ears than grizzly bears

If the bear is extremely close, take a look at the claws. A black bear’s short (less than two inches long), sharply-curved claws help them tear into rotten logs in search of insects and climb trees to escape predators. While the longer (two- to four- inches), gently-curved claws of a grizzly bear are better adapted for digging roots and excavating winter dens. Despite the differences, black bears still dig and grizzly bears can climb trees.

The claws can also be helpful in identifying the tracks of both bears. Since the grizzly bear’s claws are longer, the claw marks will be farther away from the toe marks than the black bear’s short claws. 

Another difference in the tracks is the relation of the toes to the pad. When a straight edge is aligned with the front of the pad and the rear of an outside toe on either side of the front track, a grizzly bear’s toes will all be in front of the straight edge, whereas the opposite outside toe on a black bear’s track will be partially behind the straight edge. This technique only works on the front track which is smaller and more square than the rear track. 

Grizzly or black bear tracks? (Southeast Alaska)

The main thing to remember when trying to determine a black bear from a grizzly bear is to not identify the bear based on color. Even though they are called black bears, they can also be brown, cinnamon, blonde or a combination of light and dark colors. Likewise, not all grizzly bears are brown, they can range from black to blonde and even white (such as the spirit bears in western British Columbia).

Grizzly or black bear? (Glacier National Park, Montana)

The bear below Goat Mountain wandered into a meadow long enough for me to see the straight face and lack of a shoulder hump, which confirmed that this black-colored bear was indeed a black bear.  

Note: Published in the Bonners Ferry Herald on July 19, 2012. 

Looking upstream to Libby Dam and Lake Koocanusa

Forty years after being completed (1972), Libby Dam is still fulfilling its mission of flood control on the Kootenai River. The Kootenai River is the third largest tributary of the Columbia River and over 8,900 square miles drain into Lake Koocanusa. With June precipitation being more than 300 percent of normal, the dam has helped minimize the flooding in Bonners Ferry but cannot eliminate it all. 

The record levels of rainfall prompted the U.S. Army Corps of Engineers to temporarily raise the maximum elevation of full pool by one foot and then another foot, and luckily the peak level did not exceed the first additional foot. One foot may not seem like much, but considering Lake Koocanusa is 90 miles long, the gallons add up quickly. At normal full pool elevation of 2459 feet (total depth of 370 feet), Lake Koocanusa holds 5,809,000 acrefeet of water (an acrefoot of water covers 1 acre to the depth of 1 foot and equals 325,804 gallons)--that is approximately 1.89 trillion gallons. Adding one foot to the 46,500 acres that full pool covers means an additional 15 billion gallons of storage space. 

Normally water only exits the reservoir through the generators so electricity can be generated. However, in emergency situations, such as this year, water is released through two spillways and three sluiceways because more water is entering the reservoir than can be passed through the generators without exceeding full pool. 

Libby Dam with spillways open

The spillways release water from the top of the reservoir and look like waterfalls flowing over the front of the dam. The sluiceways release water from the bottom of the reservoir. The spillways are 48 feet wide and 56 feet high and at full capacity water flows through at 1.2 million gallons per second--eight times greater than Niagara Falls which has a normal flow of 150,000 gallons per second. A stilling basin below the spillways and sluiceways helps slow the water’s velocity to prevent downstream erosion. 

In addition to spillways and sluiceways, Libby Dam was constructed with other emergency situations in mind. Although uncommon in our area, earthquakes can occur and the Libby Dam is built to withstand an earthquake up to 6.5 on the Richter scale. If structural damage does occur, the entire dam will not fail. Libby Dam is composed of 47 individual dams (or monolith sections) which act independently to hold back the water in the reservoir. The vertical lines on the front of the dam indicate the separate monoliths. If one monolith section fails, the adjacent sections are constructed to maintain their strength. 

The profile of Libby Dam is a right triangle

The sheer amount of concrete in Libby Dam holds back the water in Lake Koocanusa, not the shape of the dam. Over 7.6 millions tons of concrete were used in the construction of Libby Dam. Some dams are curved like Hungry Horse Dam near Kalispell, but Libby Dam is straight across the valley. In a cross section, Libby Dam is shaped like a right triangle with the base being 310 feet wide and the crest being 54 feet wide. At 422 feet tall and more than half-a-mile long, there is a lot more to Libby Dam than meets the eye. 

Note: Published in the Bonners Ferry Herald on July 12, 2012. 

No escaping the annoying buzz of mosquitos

Lying under the window at night I can hear the constant buzz of mosquitos swarming on the other side of the window screen. Almost asleep I hear the buzz become louder and louder until it is next to my ear. I slap the side of my head but miss--I won’t be falling asleep until I stop that annoying buzz. 

On the other side of the screen

While in Bettles, Alaska this time of year, I have a nightly ritual of going around the house and killing all the mosquitos I can find--the other night there were 24 in the bedroom alone. There is satisfaction in zapping a mosquito with one of those yellow tennis racket-looking contraptions--especially when they pop and smoke. I don’t consider it cruel because their annoying buzz has kept me up many nights as they lurk just beyond my grasp. 

The arctic tundra seems to be the ideal breeding ground for mosquitos. All mosquitos need is water, warmth and blood to thrive. Water is everywhere--from lakes to stagnant water in depressions smaller than a soup bowl. Mosquitoes don’t need much water and it doesn’t have to exist for long. A mosquito egg can hatch into larvae in as little as 48 hours and develop into an adult in four to seven days. 

Did you forget about that old tire behind the shed that filled with water during the last rainstorm? It won’t be long before a female mosquito lays eggs there and not just a few eggs, a female can lay between 100 and 300 eggs at a time. All the female needs is a blood meal to produce the eggs. Most mosquitos will stay within one mile of their hatching site but some will range up to 20 miles. 

As for warmth, the midnight sun rarely lets the temperature drop below 50 degrees Fahrenheit, which is perfect for mosquitoes. Since mosquitos are cold-blooded, they thrive in warmer temperatures. They function best around 80 degrees, become lethargic around 60 degrees and are mostly inactive below 50 degrees. 

Though they still seem to find me quickly in the morning when the temperature is hovering in the 50’s. The heat and carbon dioxide my body emits is easily detected by mosquitos. Since mosquitos can see in infrared, they can see a warm human body against a background of cooler trees and make a bee-line for it. They can also smell the carbon dioxide I exhale up to 100 feet away! 

Spend a few minutes outside and the mosquitos will find you

There is no escaping mosquitos--not for humans, not for any animal. While it may seem mosquitos gravitate towards people, some species of mosquitos actually prefer cows, horses, dogs, squirrels, birds and even frogs. Unfortunately mosquitos don’t have a main predator, such as lynx with snowshoe hares, instead they are a minor food source for numerous species, such as birds, fish, bats and other insects like dragonflies. Not even the dozens of swallows nesting around the airport can eat enough of them to put a dent in the population. 

With a rapid reproduction rate and a lifespan ranging from three to 100 days, mosquitos can easily adapt to the changing conditions of the seasons. Some mosquito eggs can lie dormant for up to five years waiting for water to refill a depression. And when cold weather strikes, mosquitos are capable of overwintering in any life stage (depending on the species). No matter what conditions prevail during the summer, mosquitos will be ready to annoy you with their buzz. 

Note: Published in the Bonners Ferry Herald on July 5, 2012.