Oregon Master Naturalist Archives - Eva Varga


January 20, 20182

My father has a pair of ravens that sit perched a top the branches of a snag on his property. They will often squawk upon our arrival and swoop down quickly to snatch up the tasty morsels we toss out to them periodically. Watching their antics is a highlight of our visit and provides a great nature study segue for our teens.

I’ve always been fascinated by ravens. When I was a young girl, my mother introduced me to her favorite author, Edgar Allan Poe. Chills ran up my spine as she read, The Raven. I now enjoy reading it each autumn when the leaves begin to fall from the trees and the cold winds begin to blow.  Teens may wish to memorize this poem.Ravens in Winter

“Deep into that darkness peering, long I stood there, wondering, fearing, doubting, dreaming dreams no mortal ever dared to dream before.” Quoth the raven, “Nevermore.”

~ Edgar Allan Poe, The Raven

Corvus Identification

Common ravens (Corvus corax) and American crows (Corvus brachyrhynchos), overlap widely throughout North America and they look very similar. Rest assured, however, that with a little practice, you can tell them apart.

You probably know that ravens are larger. They are actually the same size as a Red-tailed Hawk and will often travel in pairs. Crows, on the other hand, are seen in larger groups.

As they fly overhead, the crow’s tail feathers are basically the same length, so when the bird spreads its tail, it opens like a fan. Ravens, however, have longer middle feathers in their tails, so their tail appears wedge-shaped when open. Ravens ride the thermals and soar, whereas crows do more flapping.

Another key difference is their call. Crows give a cawing sound whereas ravens produce a lower croaking sound.

The Tower of London

The photo featured at the top of this post was taken at the Tower of London while on family holiday a few months ago. “Should the ravens leave the Tower of London, it will crumble into dust and great harm befall the kingdom,” proclaimed the official Ravenmaster we spoke to as we wandered about the grounds.

As you can imagine, the ravens who reside at the Tower of London are an attraction to travelers around the world. You can learn more about them and the role the Ravenmaster plays in their care here, At the Tower of London, a Ravenmaster for the Digital Age.

Living Books

Ravens in Winter by Bernd Heinrich is a wonderfully written narrative compiled from the author’s field notes and studies all aimed at understanding raven behavior. In 1984 he was determined to find out why ravens call to each other when they discover food, a rare example of sharing in the wild. For the next four years he spent winter weekends observing these birds at a remote site in Maine, braving fierce weather, lugging enormous amounts of bait to lure ravens to his study area and sleeping in a cabin where temperatures often plunged below zero at night.

A Professor Emeritus of Biology at the University of Vermont, Henrich is the author of numerous books, including Bumblebee EconomicsMind of the Raven (which we also enjoyed), and TheHoming Instinct. He has received the John Burrough’s Medal for Nature Writing and has been nominated for a National Book Award for Science.Ravens in Winter provides an in-depth look at raven ethology – particularly their intelligence and playfulness. It is a great living science book for teens, providing a visual picture of the scientific method.

To expand on your Corvid nature study, you may consider extending with Native American and Norse mythology.

Corvus Study in the Wild

Ravens and crows have the keenest intelligence of all our common birds. Taking inspiration from Heinrich’s study, winter is the perfect time to get outdoors and study the behavior of the Corvus genus ourselves. Their nests are often easier to see in the winter when the foliage is absent from the trees. However, most do build their nests in evergreens. Here are few questions or things to ponder as you observe them – be sure to record your observations in your nature journal:

  • Describe its colors when seen in the sunlight.
  • Describe the general shape of the crow or raven.
  • Are its wings long and slender or short and stout?
  • Is the tail long or short? Is it notched or straight across the end?
  • Describe its feet. Are they large and strong or slender? How many toes does it have? How many are directed forward and how many backward?
  • What is it doing? Describe its behavior or activity.
  • Describe its call.
  • Describe its beak.
  • Where and of what material did it build its nest?
  • If they are feeding in a feed, is there a sentinel or guard posted?
  • What do they feed upon?

Sit down with your sketch book and illustrate a few. Try to capture its movement and different poses with quick, light sketches. Take photographs if the weather is not conducive to sketching outdoors.

Build a Feeder

There are two beneficiaries to setting up a bird feeder in you backyard … birds and people. In regards to the first beneficiary, you should consider:

  1. accessibility to the birds;
  2. shelter from the wind, snow, and rain;
  3. vulnerability to window strikes; and
  4. safety from predators, especially cats.

In regards to the latter, ponder the following:

  1. ready visibility from a window;
  2. ease of filling and maintaining; and
  3. capacity, which determines refilling frequency.

With these thoughts in mind, you can begin to research what type of feeder you would like to build and the potential placement. There are many options to choose from and building plans are easily found at your local library, online, or from local bird watching groups like the Audubon Society.

There are also many opportunities to engage in real science – collecting data on bird migration patterns and nesting behaviors for a variety of citizen science projects. Two that come to mind immediately are Project FeederWatch and the Great Backyard Bird Count.

The Nature Book Club

Welcome to the first The Nature Book Club Monthly Link Up. The monthly link up will begin on the 20th day of each month.

The monthly book club is devoted to connecting children to nature. There is a theme for each month in 2018. The theme this month is winter birds and nests.

We welcome your nature book and activity related links. Read on for more details and for a giveaway!

image of a stack of books in the grass with text overlay listing monthly theme

The Nature Book Club is brought to you by these 15 nature loving bloggers which are your co-hosts! Are you following them? If you don’t want to miss anything, be sure to follow each one.

Here are the co-hosts, their choices of books, and activities for the month.

Something 2 Offer
Birds, Nests, and Eggs Nest Scavenger Hunt

The Usual Mayhem
The Boy Who Drew Birds Free artist study set (John James Audobon)

Preschool Naturally
Whose Nest Is This? Nest Building Activity

Tina’s Dynamic Homeschool Plus
(Backyard Bird Series) CardinalsFree Northern Cardinal Unit Study & Lapbook.

Rule This Roost
Fine Feathered Friends: All About BirdsDIY Bird Feeders

Hide The Chocolate
Those Darn Squirrels Fly SouthFree online book club.

The Homeschool Scientist
Birds, Nests, and EggsMake a Suet Feeder

Forgetful Momma
Snowy Owls Snowy Owl Craft

Table Life Blog
A Nest is NoisyArt Project.

Eva Varga
Ravens in Winter: Nature Study Activities and Lessons for TeensWinter Bird ID

Wind in a Letterbox
Birds for Beginners in Southern AfricaNature Journal Entry

Rainy Day Mum
Coming HomeNeedle Felted Robin

Handbook of Nature Study
Backyard Birds Field Guide for Young NaturalistBackyard Bird Nature Study

The Playful Scholar
TBD – How to Make Hanging Suet Ornaments

Freshly Planted
NestsNest weaving

WHOOP! – The Nature Book Club Giveaway!

We’re so excited about this month’s freebie. It is an ebook, Backyard Science – Easy Activities for All Ages, by The Homeschool Scientist.
A huge Thank You to The Homeschool Scientist!

Backyard Science Giveaway
Click on the link above. It’s free until February 4, 2018. No coupon code required.

Party Rules

  • Choose an engaging nature book, do a craft or activity, and add your post to our monthly link up.
  • The link up party goes live at 9:00 a.m. EST on the 20th of each month and stays open until 11:59 p.m. EST on the last day of the month. Hurry to add your links!
  • You can link up to 3 posts. Please do not link up advertising posts, advertise other link up parties, your store, or non-related blog posts. They will be removed.
  • By linking up with us, you agree for us to share your images and give you credit of course if we feature your posts.That’s it!
  • Let’s party.

 




January 24, 20171

To finish up his Second Class rank requirements for Boy Scouts recently, I was helping my little man find photographs of wildlife that he has observed. As we dug through our photo archives, I was reminded of a fun little Oregon Nature Quiz: Early Summer Edition that I posted several months ago. I had posted it with the intention of making it a quarterly series but sadly, life distracted me and I let it slip my mind.

Oregon Nature Quiz #2: Wildlife Edition

How Well Do You Know Oregon?

Here are five of the photos my son selected to submit to his Scoutmaster. Can you identify the wildlife represented here? Whose Been Here? Oregon Nature Quiz: Boy Scout Rank Wildlife Edition @EvaVarga.net

Who Am I? Oregon Nature Quiz: Boy Scout Rank Wildlife Edition @EvaVarga.net

What Happened Here? Oregon Nature Quiz: Boy Scout Rank Wildlife Edition @EvaVarga.net

I'm Friendly. Or Am I? Oregon Nature Quiz: Boy Scout Rank Wildlife Edition @EvaVarga.net

My, What Big Teeth You Have. Oregon Nature Quiz: Boy Scout Rank Wildlife Edition @EvaVarga.net

Answers:

1. North American Raccoon tracks along the banks of a river

In the wild, raccoons often dabble for underwater food near the shore-line. They then often pick up the food item with their front paws to examine it and rub the item, sometimes to remove unwanted parts. This gives the appearance of the raccoon “washing” the food.

Originally, raccoon habitats were solely deciduous and mixed forests, but due to their adaptability they have extended their range to mountainous areas, coastal marshes, and even urban areas. Though previously thought to be solitary, there is now evidence that raccoons engage in gender-specific social behavior. Related females often share a common area, while unrelated males live together in groups of up to four animals to maintain their positions against foreign males during the mating season, and other potential invaders.

Intrigued by animal tracks and wildlife signs? Check out these ideas for Exploring Animal Tracks with students.

2. Pacific Tree Frog

Pacific tree frogs are common on the Pacific coast of Oregon and Washington. They occur in shades of greens or browns and can change colors over periods of hours and weeks. They occur in shades of greens or browns and can change colors over periods of hours and weeks. Eggs of the Pacific tree frog may be consumed by the rough-skinned newt and other amphibians.

They are found upland in ponds, streams, lakes and sometimes even further away from water. The Pacific tree frog makes its home in riparian habitat, as well as woodlands, grassland, chaparral, pasture land, and even urban areas including back yard ponds.

3. Black Bear claw marks and Acorn Woodpecker holes on the trunk of an apple tree

In the early fall, when the apples are ripe, it is not uncommon to see claw marks on apple trees, particularly in old pioneer orchards that have been abandoned. Brown and American black bears are generally diurnal, meaning that they are active for the most part during the day, though they may also forage at night.

Most bears have diets of more plant than animal matter and are completely opportunistic omnivores. Knowing when plants are ripe for eating is a learned behavior. Bears may mark territory by rubbing against trees and other objects which may serve to spread their scent. This is usually accompanied by clawing and biting the object.

Interested in learning more about animals and the study of wildlife? Check out these great animal webcams.

4. Golden Mantle Ground Squirrel

Scientists classify the golden-mantled ground squirrel as a true ground squirrel, though it will climb trees to reach seeds. Its genus name Spermophilus is Greek for “seed loving.” Like other ground squirrels, the golden-mantle packs seeds and fruit in its cheek pouches and stores the food in burrows, puts on a thick layer of fat, and hibernates in winter. Golden-mantled ground squirrels eat their stored food in early spring, when seeds and fruit are scarce. In addition to seeds and fruit, the omnivorous ground squirrel eats fungi, insects, bird eggs, small vertebrates, and carrion.

Though the golden-mantled ground squirrel can vocalize, it remains silent most of the time. When alarmed, it chirps and squeals. Though not especially aggressive, it growls when fighting with other ground squirrels. Though tempting, it’s not a good idea to feed these or any other wild animals; it distracts them from searching for natural foods, which they must eat in large quantities to survive. Unlike most other ground squirrels, the golden mantle is a loner. It only spends time with others of its kind as a youngster with its mother and siblings.

5. North American Beaver teeth marks on the trunk of an oak tree

Beaver (Castor Canadensis) are known for building dams, canals, and lodges (homes). Their colonies create one or more dams to provide still, deep water to protect against predators, and to float food and building material. While they don’t generally use trees of the size pictured here in their dams, it is fascinating to watch the process of a beaver dam under construction which play a critical role in the ecology of our streams. Learn more in my post, The Industrious Beaver: Nature’s Engineers.



August 7, 2016

I love slugs! They are one of my favorite animals, particularly if limiting the scope of the question to invertebrates. In my opinion, they are one of the most beautiful and fascinating organisms.

You’re likely thinking I have lost my mind. “You really think this guy is beautiful?” 

Sea Slugs, Snails, and Sea Hares
Pictured here is the banana slug

Yes, I do. Well, actually, in my mind I was picturing his close relative the sea slug or nudibranch. This summer, I have been volunteering at the new Marine Life Center at the Oregon Institute of Marine Biology and I’ve thereby had the opportunity to learn so much about these fascinating animals. Let me introduce you to the gastropods.

Class Gastropoda 

The Gastropoda or gastropods class, more commonly known as snails and slugs, are a large taxonomic class within the phylum Mollusca. A very diverse group with 60,000 to 80,000 living species (second only to insects in number of species) that includes snails and slugs of all kinds and all sizes from microscopic to large. There are many thousands of species of sea snails and sea slugs, as well as freshwater snails, freshwater limpets, land snails and land slugs.

Sea Slugs, Snails, and Sea Hares @EvaVarga.net
How many sea slugs can you find in this picture?

The anatomy, behavior, feeding, and reproductive adaptations of gastropods vary significantly from one group to another. The class also inhabits an extraordinary diverse habitats including gardens, woodland, deserts, mountains, rivers and lakes, estuaries, mudflats, the rocky intertidal, the sandy sub-tidal, the abyssal depths of the oceans including the hydrothermal vents, and numerous other ecological niches, including parasitic ones.

Sea Slugs, Snails, and Sea Hares @EvaVarga.net
Gastropoda means the belly-foot animals

Snails & Other Shelled Gastropods

Commonly, snails are those species with a single external shell large enough that the soft parts can withdraw completely into it. Those with a shell into which they cannot withdraw are termed limpets.

The marine shelled species of gastropod include species such as abalone, conches, cowries, periwinkles, whelks, and numerous other sea snails. Each produce seashells that are coiled in the adult stage. In a number of families of species, such as all the various limpets, the shell is coiled only in the larval stage, and is a simple conical structure after that.

Sea Slugs, Snails, and Sea Hares @EvaVarga.net
Pictured here is Hermissenda crassicornis

Slugs or Gastropods Without External Shells

Those gastropods without a shell, and those with only a very reduced or internal shell, are usually known as slugs. The various families of slugs are not closely related, however, despite a superficial similarity in the overall body form.

Sea Slugs

The phrase “sea slug” is perhaps most often applied to nudibranchs and they come in an outstanding variety of shapes, colors, and sizes. With translucent bodies, they appear in just about every color on the rainbow. Of course, these bright colors are cause for warning to potential predators that they are poisonous with stinging cells. It is their colors that so fascinate me.

Like all gastropods, they have razor-sharp teeth, called radulas. Most have two pairs of tentacles on their head used primarily for sense of smell, with a small eye at the base of each tentacle. Many have feathery structures (ceratia) on the back, often in a contrasting color. These act as gills.

All species of sea slugs have a selected prey, that is specifically fitted for them to hunt. Amongst the diverse prey are jellyfish, bryozoans, sea anemones, sponges, and other various organisms including other sea slugs.

Sea Slugs, Snails, and Sea Hares @EvaVarga.net
Pictured here is Phyllaplysia taylori

Sea Hares

The sea hares, clade Aplysiomorpha, are often quite large and sometimes described as large sea slugs. They have a small, flat, internal shell composed of proteins. The name derives from their rounded shape and from the two long rhinophores that project upwards from their heads and that somewhat resemble the ears of a hare.

The greatly modified shape of the sea hare and the fact that it orients its body lengthwise along the leaves makes it almost invisible on the sea grass Zostera. An herbivore, it feeds by grazing the film of organisms, mainly diatoms, off sea grass leaves, leaving a characteristic feeding scar on the leaves.

Take it Further

Learn more about Phyla Mollusca in my earlier post, Echinoderms and Molluscs.  You might also be interested in my in-depth zoology curriculum specifically designed for middle school students.

zoology



June 29, 20162

I have always loved the outdoors and enjoy sharing my passion for nature study with others. I’ve recently completed my coursework to become a certified Oregon Master Naturalist.

To celebrate, I thought it would be fun to create a little quiz to help you get to know Oregon a little better. My vision is to create a new quiz every quarter.

Oregon Nature Quiz #1

How Well Do You Know Oregon?

Here are five photos of plants and animals that are found on the Oregon Coast. Can you identify them? (Hint: All of these photos were taken on the Oregon coast)

  1. What kind of rodent is this?

mammal

2. What is this creepy looking black thing?

fungi

3. Can you name this flower?

flower

4. Is this cutie a lizard or amphibian? Can you identify the genus?

herp

5. This invertebrate is a common sight along the trails and even in our gardens. What is it? slug

Answers:

1. The California ground squirrel (Otospermophilus beeches) is pictured here on the rocky shoreline in Depoe Bay. The squirrel’s upper parts are mottled, the fur containing a mixture of gray, light brown and dusky hairs; the underside is lighter, buff or grayish yellow. The fur around the eyes is whitish, while that around the ears is black. Head and body are about 30 cm long and the tail an additional 15 cm. As is typical for ground squirrels, California ground squirrels live in burrows which they excavate themselves. Some burrows are occupied communally but each individual squirrel has its own entrance. They commonly feed on seeds, such as oats, but also eat insects such as crickets and grasshoppers as well as various fruits.

2. It is rather common in the maritime Pacific Northwest, Frog Pelt Lichen (Peltigera neopolydactyla) can range in color from bluish green to olive brown. It is found growing on both rocks and dead wood, in shady, open forests at varying altitudes. A large, loosely appressed leaf lichen, the lobes are broad, 10-25 mm wide, and the upper surface hairless. Often bearing brownish, tooth-like fruiting bodies on raised lobes along the lobe margins, the lower surface is whitish, cottony, bearing low, broad, brownish or blackish veins and long, slender holdfasts (rhizines).

3. Trillium (sometimes called Wakerobin) is a genus of perennial flowering plants native to temperate regions of North America. Growing from rhizomes, they produce scapes (similar to a stem) which are erect and straight in most species but lack true, above ground leaves. Three large photosynthetic bracts (modified leaves) are arranged in a whorl about the scape. The flower has three green or reddish sepals and usually three petals in shades of red, purple, pink, white, yellow, or green.

4. Rough-skinned Newts are amphibious and are often seen moving to breeding sites during the breeding season. Migration to and from breeding sites varies among populations. Some newts spend the dry summer in moist habitats under woody debris, rocks, or animal burrows with adults emerging after the fall rains. In some populations, adults remain in the ponds and lakes throughout the summer and migrate back onto land in the fall when the rain starts. Often they will form large aggregates of thousands of newts in the water.

Poisonous skin secretions containing the powerful neurotoxin tetrodotoxin repel most predators. The poison is widespread throughout the skin, muscles, and blood, and can cause death in many animals, including humans, if eaten in sufficient quantity. Populations in Crater Lake have been shown to lack this neurotoxin. In most locations the Common Gartersnake, Thamnophis sirtalis, is the only predator of the newt.

5. The infamous banana slug is the common name for three North American species of terrestrial slug in the genus Ariolimax. These slugs are often yellow in color and are sometimes spotted with brown, like a ripe banana. These shell-less mollusks are detritivores or decomposers. They process leaves, animal droppings, moss, and dead plant material, and then recycle them into soil humus.

SCORING:
5 points: You must be a nature docent!
4 points: You are at home on the coast.
3 points: You think the coastal forest is beautiful, but would never spend the summer here.
2 points: You guessed randomly, right?
1 or 0 points: You’d really rather stay indoors.