Tag Archives: fauna

Common Garter Snake (Thamnophis sirtalis)

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Things that will eat slugs are a welcome sight in any garden. The Common Garter Snake, along with most snakes in Oregon, is considered ‘beneficial’ because of their diet. The Common Garter Snake will eat slugs, grubs, mice, voles, earthworms, rats, frogs and tadpoles, and generally anything they can overwhelm.

Species in Oregon

There are four species of Garter snakes in Oregon: The Common Garter and Western Terrestrial Garter are abundant throughout Oregon, except the mountains. The Northwestern Garter resides in western Oregon. The Aquatic Garter resides in southwestern Oregon. Snakes are usually black, dark brown or green with a light-colored or red stripe and can reach 48-inches in length.

Where to look

You can find Garter snakes in a variety of habitats such as urban lawns, forests, woodlands, fields, and grasslands. Look for Garters near water, such as a wetland, stream, or pond. Water provides a place to hunt amphibians and as a potential escape strategy.

When disturbed, a garter snake may coil and strike. Typically, the Garter will hide its head and flail its tail. It may also discharge a malodorous, musky-scented secretion or slither into the water to escape a predator. Garters do not have the capacity to seriously injure humans, even though they have small amounts of a mild venom.

Predation

Garter snakes give birth to live and independent young. Gestation lasts a couple of months with birth rates reaching nearly 100. Juvenile snakes are often killed by predators, cars, and lawnmowers! Predators include birds of prey, crows, egrets, herons, cranes, raccoons, otters, bull frogs, shrews, and other snake species (such as the coral and king snakes).

Communication

Garter snakes use a complex communication system using pheromones. The pheromones cues are communicated through tongue-flicking behavior. This system helps them find other snakes through pheromone-scented trails and making it key to breeding.

Learn how to invite these beneficial predators into your garden by reading the Oregon State Extension publications Common Garter Snake and Attract Reptiles and Amphibians to Your Yard.

REFERENCES:
Snakes slither through the garden eating slugs, grubs and other pests (https://extension.oregonstate.edu/news/snakes-slither-through-garden-eating-slugs-grubs-other-pests)
Garter Snakes, Wikipedia (https://en.wikipedia.org/wiki/Garter_snake)
Oregon Department of Fish & Wildlife (https://myodfw.com/wildlife-viewing/species/snakes)

Gray Whale (Eschrichtius robustus)

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Mother and calf surfacing for air. www.unsplash.com

Approximately 18,000 Gray Whales migrate twice each year just off the Oregon coast. Approximately 200 Gray Whales hang out year around near the central coast area. This makes them relatively easy to see.

Gray Whales are the most common of the 10 species of whales, dolphins, and porpoises that reside on the Oregon Coast. The Whale Watch Center in Depoe Bay reports seeing as many as 50 whales per day during December – January and again in the spring.

Where are they going?

The whales migrate south to breeding grounds in the Sea of Cortez, Mexico and north to Alaska shortly thereafter. Gray Whales make the longest annual migration of any mammal on earth of over 12,000 miles round trip.

How to spot a Gray Whale

One might think that spotting something so common and the size of a city bus should be easy. Gray Whales can weigh up to 80,000 pounds and reach 50 feet in length. That doesn’t mean that they are easy to see all of the time. The mottled gray color, along with barnacles and whale lice, can make even the large adults swimming just a few miles from shore a challenge.

The easiest way to find them is to grab binoculars and find a high view point on a calm morning. Look for a bushy puff of white on the water. This spout or blow, which should be visible for about five seconds on a calm day. The blow can rise up to 15-feet and occurs as the whale exhales warm, moist air when surfacing.

Finding spouts

Gray Whales typically blow three to five spouts in a row, about 30 to 50 seconds apart as they swim. You may need to move the lens slightly to account for them swimming. Move left (or south) in the winter, and right (or north) in the spring.

Keep watching and you may see the whale use its tail to dive to the sea bottom for three to six seconds. It will then return to the surface to repeat the spouting breathing rhythm.

What is the whale diving for?

Grays fill their mouths with mud from the sea bottom. The mud is strained through a filter-feeding system, called baleen, on the upper jaw of their mouths. Baleen is keratin which is the same substance as human fingernails and hair.

Water and mud is pushed out through the baleen trapping krill and small fish. Many whales have baleen, but not all use it in the same manner. Grays only use only one side of the baleen which is unique in the whale community.

There are several places to learn more about the Gray Whale. Here are a few ideas:
—Visit a Visitors’ Guide to Whale Watching on the Oregon Coast (https://www.coastexplorermagazine.com/display.php?url=a-guide-to-whale-watching-on-the-oregon-coast)
–Visit the Whale Watching Spoken Here program (https://orwhalewatch.org/) that has information on best places to see whales, volunteer training, and more.
–Visit Oregon State Parks, Whale Watching Center in Depoe Bay, (https://oregonstateparks.org/index.cfm?do=parkPage.dsp_parkPage&parkId=183 ) which has videos of spouting whales, and more.

REFERENCE:
–Oregon Department of Fish and Wildlife (https://myodfw.com/wildlife-viewing/species/whales-dolphins-and-porpoises)
–Shoreline Education for Awareness, Inc. Friends of the Southern Oregon Coast National Wildlife Refuges (https://sea-edu.org/2019/11/25/whale-migration-is-upon-us/)
–Wikipedia, Baleen (https://en.wikipedia.org/wiki/Baleen)

American crow (Corvus brachyrhynchos)

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American crow (Corvus brachyrhynchos)

The American crow, the more you know about them the more interesting they are. Crows are a large, intelligent, all-black bird with a hoarse, cawing voice that is familiar over much the continent.

They are common sights in treetops, fields, and roadsides, and in habitats ranging from open woods and empty beaches to town centers. These birds are inquisitive, somewhat mischievous, and good learners and problem-solvers.

They usually feed on the ground and eat almost anything, including earthworms, insects and other small animals, seeds, and fruit as well as garbage and chicks they rob from nests.

Communal Roosting 

American crows are very social, sometimes forming flocks in the thousands. In the winter, American crows congregate in larger numbers to sleep in communal roosts.

Roosts can consist of a few hundred up to two million crows. Some roosts have been forming in the same general area for well over 100 years. 

Mobbing

American crows will work together as a group to harass or drive off predators, a behavior known as mobbing. This interesting video features a crow solving 8 puzzles in a row in order to reach food.

The crow has also been the subject of Native American legends, including this one: http://nativeamericans.mrdonn.org/stories/raven.html