Aquatic Science Studies: 10 Activities for Teens

Aquatic science – the study of wetlands, freshwater and marine systems – can be a little intimidating. With adult supervision and clear boundaries and expectations outlined in advance, taking time to explore these diverse habitats can be very rewarding. The focus of my post today is on aquatic systems – estuaries, ponds, lakes, streams, and rivers.

image of the Sundial Bridge in Redding, California with text overlay Aquatic Science Studies: 10 Activities for Teens @EvaVarga.net

Physical Factors of Aquatic Systems

Abiotic factors are components of a natural environment that are not alive. In other words, abiotic factors are the physical or chemical parts of the environment that affect the organisms in that environment. For aquatic ecosystems, these factors include light levelswater flow ratetemperaturedissolved oxygenacidity (pH), salinity, and depth.

Upper elementary and middle school students are capable of exploring how each of these abiotic factors affect the environment. If you are just getting started, I encourage you to begin with a small pond. Here, children can enjoy the freedom to explore safely while also focusing their attention on specific learning goals – observations and data collection.

The most distinctive area of an aquatic system is likely the riparian zone. Acting as buffers between upland areas and open water, riparian zones help filter pollutants such as nutrients and sediment. Healthy riparian vegetation helps to reduce stream bank erosion and maintain a stable stream channel. Vegetation also provides shade, which works to lower water temperatures.

Conduct a riparian area survey with your students with my guide, The Many Parts of a Stream Bank. This half-day field excursion is a wonderful outdoor science experience for teens.

A few years ago, my STEM Club was immersed in a three part ecology unit, Field, Forest, & Stream. One of their favorite activities in this unit study was the stream survey – after all, we spent much of our time in the stream – the perfect way to cool off in the stifling heat of a Redding summer. Some of the physical factors we investigated were bottom substrate, channel shape, and the velocity of the current.

image of teen setting a crab trap at low tide

Flora & Fauna of Aquatic Systems

Move beyond the physical factors to explore the impact these abiotic factors have on the animals and plants that make their home in freshwater streams and rivers. Expand on your stream survey to include the flora (plants) and fauna (animals) of the riparian zone. Take it further by investing how biotic factors such as invasive species affect the native organisms.

Reach out to your local fish and wildlife agency or watershed associations to inquire about their outreach classes and internships. Many provide opportunities for youth to get involved in long-term projects.

For example, my daughter and I recently collaborated with an undergraduate looking at the effects of the invasive European green crab on our local estuaries. We spent the day collecting traps that had been set out the day before and in turn setting them out in new locations. We also collected data related to the abiotic and biotic factors:

  • What crab species are present?
  • What is the water temperature? air temperature?
  • What is the time of day and location?
  • Of the non-natives collected, what is the size and sex distribution?

Design a simple lab experiment to explore how environmental changes affect aquatic organisms. I’ve outlined the procedure in my post, Environmental Science: How Species Respond to Environmental Changes.

Inquiry based science projects like these allow students the opportunity to become the scientist themselves – using the tools and resources of real scientists. For more ideas, here are 100 Science Fair Projects.

Beavers are the largest rodents in North America, and they spend most of their time in the water. Nature’s engineer, the industrious beaver is often cited as an example of a keystone species because through its dam-building behaviors it has major influences on both the vegetation of an area and the water table.

Initiated by the fur trade, the consequences of losing beavers has had a profound impact on our ecology: streams eroded, wetlands dried up, and species from salmon to swans have lost vital habitat. A fabulous non-fiction book for adults and advanced students is Eager: The Surprising, Secret Life of Beavers and Why They MatterThe author outlines the strategies undertaken by scientists, ranchers, and passionate citizens who recognize that ecosystems with beavers are far healthier, for humans and non-humans alike, than those without them.

Do you have beavers in your local area? What about the past? How has the range of beavers (or another animal) changed over the years? What impact does its absence or presence have on the ecosystem?

For younger readers, consider Salmon Stream by Carol Reed-Jones. The illustrations and text blend well together to give a great sense of the ecosystem and watershed. Written in cumulative verse, the author has created a book that is enjoyable for students and a valuable teaching resource. Awarded the CBC/NSTA Outstanding Science Trade Book, it provides an accurate description of the life cycle of salmon – from their form as eggs in a stream to the wide ocean, eventually making a hazardous journey home to their stream of origin. At the back is a section on salmon facts and what makes a good habitat for them, teaching the basics of ecology and why clean streams and waters are so important.

To accompany this book, I created a printable you can download FREE to illustrate the life-cycle of salmon.

simple graphic image of green grass on white background with text Nature Book ClubWelcome to the Nature Book Club Monthly Link Up. Devoted to connecting children to nature, the monthly link up will begin on the 20th day of each month. We welcome your nature book and activity related links. Read on for more details.

See all the great posts from The Nature Book Club’s co-hosts in August

The Nature Book Club is brought to you by these 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.

Seasonal Pond Study and Printables from Barbara at Handbook of Nature Study
Sensory Bin and Observation Notebooking Page from Jenny at Faith & Good Works
Pond Life Printable Pack from Emily at Table Life Blog
Aquatic Science Studies: 10 Activities for Teens from Eva at Eva Varga
Above and Below a Pond Unit Study and Lapbook from Tina at Tina’s Dynamic Homeschool Plus
Online Book Study about water cycle from Dachelle at Hide the Chocolate
STEAM Challenge – Does Water Ever Flow Up? from Erika at The Playful Scholar
Who Was?® What Was?® Where Is?® Book Series: Where is the Mississippi River? from Sharla at Minnesota Country Girl
River Exploration and Frog Catching from Thaleia at Something 2 Offer

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!


10 Nature Discoveries on the Sandy Shore

The sandy shore dominates much of the open coastline of the Pacific Northwest, stretching uninterrupted for miles in many regions. These dynamic habitats represent the most physically controlled of all the nearshore marine habitats and are considered one of the hardest places to live. As such, understanding the nature of the habitat and the animals that live there is important.image of a teen walking on a sandy beach with text overlay "Nature Discoveries on the Sandy Shore: 10 Activities for Teens" @EvaVarga.net

Sandy beaches are in a constant state of change and motion. Animals on exposed sandy beaches must protect themselves from shifting, abrasive sand and heavy surf.

Hands-on Activities to Explore the Sandy Shore

My family and I have spent much time exploring the ecology of the sandy shore and immersing ourselves in nature discoveries. There are many opportunities to learn more about this environment. Here are few ideas to help you get started:

Collect samples of beach sand from different beaches and classify each into coarse, medium, and fine sand. Can you see evidence of animal life in the samples?

Send the kids on an scavenger hunt of the intertidal invertebrates – note that many of these are not residents of the shifting sands of the sandy shore but are found clinging to the rocks and along the margins shoreline.

Be ready for the unexpected; you never know what you might discover while walking along the sandy beach like these Rare, Bizarre Creatures from the Deep. Finding an animal or plant that is unfamiliar to you is a great opportunity to seek out the answer. Can you find it in a guidebook? Do others know? Consider reaching out to local experts (remember to bring a photo) for help. Resource specialists at Fish & Wildlife offices are eager to answer questions and share their knowledge with the public.

getting started in 5 exercisesBegin a nature journal and showcase your discoveries. Here’s a peak at one of my son’s earliest entries, The Elusive Brittle Star: An Hawai’ian Nature Study. Need help to get started? Check out my tutorial, Keeping a Nature Journal: Getting Started in 5 Exercises.

You may also be interested in a college level course, Nature Journaling in the Classroom. The course is offered through the Heritage Institute and optional, university credit is available.

Do a little research to learn more about the animals that live in the surf-swept coastline. How are they adapted to life in this physically demanding habitat? Compare and contrast the means of mobility of two animals commonly seen on California’s Central Coast: Ventura Beach: the Pacific Mole Crab and By-the-Wind Sailor. Make a list of the adaptations you have observed.

image of two marine invertebrates: By the Wind Sailor (jellyfish) and Pacific Mole CrabChallenge your kids to design their own plant or animal specially equipped to survive on the sandy shore. Draw a picture of the organism or build a 3D model. Tell how it is adapted to life here.

Take Action to Protect the Sandy Shore

As a life long resident of the Oregon coast, the condition of our local beaches and ecosystems is very important to me. The idea of citizen science or “public participation in scientific research,” has also always been a passion of mine. Here are a few ideas in hopes of inspiring your family to get involved:

Take part in aBioBlitz –  an event that focuses on finding and identifying as many species as possible in a specific area over a short period of time. We took part in 2014 but they happen annually.

image collage of a young girl upcycling plastics to create artOrganize a family beach clean-up and do your part to spread the word about the dangers of single-use plastics like Washed Ashore

Feeling inspired? Collect plastic bottle caps to create a colorful mural and donate it to a local non-profit.

Just for fun, create a Labyrinth on the Beach and invite others to join you. Encourage participants to make a pledge to do their part to make a difference.

Guidebooks to the Sandy Shore & Other Habitats

The Beachcomber’s Guide to Marine Life in the Pacific Northwest by Thomas M. Niesen is one of my favorite marine ecology guides.  Each page is features incredible hand illustrations (by artist David Wood) that really capture the organism with a detailed simplicity.  Additionally, black and white images (though some are a little dark) and 16 pages of color photographs in the center of the book provide  excellent coverage.

Though this is not a pocket guide, Dr. Niesen writes in very clear language to help you identify what you are looking at, learn about its life habits, as well as its habitat. Organized with an emphasis on habitats and arrangement by type of organism within each habitat (sandy beach, estuaries, rocky intertidal, open ocean, etc.) is extremely helpful. Niesen also goes into great detail about the different tidal zones and the particular creatures you will find in each zone.

simple graphic image of green grass on white background with text Nature Book ClubWelcome to the Nature Book Club Monthly Link Up. Devoted to connecting children to nature, the monthly link up will begin on the 20th day of each month. We welcome your nature book and activity related links. Read on for more details.

See all the great posts from The Nature Book Club’s co-hosts in July

The Nature Book Club is brought to you by these 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.

Seashore Observations Printable Activity from Barbara at Handbook of Nature Study

Seashells by the Seashore | Notebooking Pages from Jenny at Faith & Good Works

Beach Scavenger Hunt from Emily at Table Life Blog

10 Nature Discoveries on the Sandy Shore from Eva at Eva Varga

Turtle in the Sea Online Book Club from Dachelle at Hide the Chocolate

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!


A Guided Tide Pool Hike with a Master Naturalist

Having grown up on the Oregon coast, I have been fascinated by marine animals since I was a young girl. I spent many long summer days exploring the tide pool and estuarine habitats in my neighborhood.

A naturalist at heart, I have inundated myself in ecology and natural sciences ever since, completing the coursework to become an Oregon Coast Master Naturalist a few years ago. Today, I am delighted to take you on a guided tide pool “hike” to one of the hidden gems of the Oregon seashore.

Cape Arago State Park

The tide pools at Cape Arago are incomparable. Here, you’ll find easy access to both the North and South Coves of Cape Arago. Tucked away below the cliffs, a short walk along the steep trails will take you to a secluded cove where tide pools and fossils can be found.

The south trail leads to tide pools teaming with diverse sea life. The north trail lets visitors view offshore colonies of seals and sea lions (however, the trail is closed from March – June to protect the seal pups during birthing season). Visitors to the area can also enjoy whale watching, crabbing, fishing, and scuba diving.

Nearby, there are two additional state parks: Sunset Bay (a sandy beach protected by towering sea cliffs – perfect for sunbathing and swimming) and Shore Acres (a lushly planted garden perched on rugged sandstone cliffs high above the ocean – once the famed estate of Louis Simpson).

Let’s now begin our guided hike of the south cove at Cape Arago.

Guided Tide Pool Hike

Upon hiking down the south trail you will first come to a small sandy beach. There is often driftwood and marine debris along the high tide line, pushed up against the base of the cliff atop the rocks and small boulders.

Purple Olive Snails

image of purple olive snails buried in the sand. Text overlay reads A Guided Tide Pool Hike with a Master Naturalist @EvaVarga.netAs you walk nearer the shoreline to the waters edge, you may see tiny little bumps in the sand. Olivella biplicata, commonly known as purple dwarf olive snails, burrow themselves in sand, leaving a plowed trail behind it. The foot is wedge shaped to facilitate plowing.

While burrowing it raises its long siphon up through the sand as a snorkel. They can be found nearshore on fairly quiet, protected beaches and farther offshore on more exposed beaches. Their predators include the seastarsoctopus, moon snails, and gulls. Most active at night, often move up and down the beach with the tide. Omnivorous, they eat kelp blades and both live and dead animal material.

Take a closer look, however. Some of these snails are not like the other.

Hermit Crabs

The snail shell at the top is inhabited by a hermit crab. There are more than 1000 species of hermit crabs -decapod crustaceans that possess an asymmetrical abdomen that is concealed in a scavenged mollusc shell which it carries around. As the hermit crab grows, it will seek out a larger shell.

Young boy holding a purple shore crab with text A Guided Tide Pool Hike with a Master Naturalist @EvaVarga.netShore Crabs

Hermits are not the only crabs you’ll observe in the tide pools. Crawling about between rock crevices and amongst the blades of kelp and marine algae are a diverse number of small crabs, each with its own distinguishing characteristics.

  • Purple shore crabs – Hemigrapsis nudus (pictured above) reaches sizes of approximately 4.0–5.6 cm and is generally dark purple in color, although it may be olive green or red, with white or cream markings. The color of the legs matches the color of the carapace but the white-tipped claws are a lighter color with purple or red spots. These markings distinguish it from the similar…
  • Lined shore crabs – Pachygrapsus crassipes, whose chelipeds lack spots.
  • Oregon shore crab – Hemigrapsis oregonensis is a similar species with setae or small hairs on its legs, a distinguishing characteristic the other two lack
  • Porcelain crabs – a flat, round body (perfectly adapted to life between rocks) with two large front claws, these delicate crabs readily lose limbs when attacked, and use their large claws for maintaining territories.

Blood star - a red, five armed sea star common on the Oregon coastSea Stars

No matter the depth or the substrate, these spiny skinned invertebrates are among the most successful marine creatures inhabiting the coast. The abundance and number of stars found along the west coast of North America is without equal in the world. I highlight just one in my post today.

Henricia leviuscula, the Pacific blood star, feeds mainly on sponges. It is fairly stiff with only small papulae (skin gills) and tube feet. It seems to rely much more on seawater uptake through the madreporite (a series of seawater-filled ducts that function in locomotion, feeding, and respiration) than do other sea stars of comparable size.

Ventral view of a Gumboot Chiton Chitons

The gumboot chiton, Cryptochiton stelleri, can be found clinging to rocks, moving slowly in search of its diet of algae which it scrapes off of rocks with its rasp-like retractable radula, covered with rows of magnetite-tipped teeth.

Unlike some other chiton species, C. stelleri has well-developed ctenidia (gills) in the groove beside the foot (pictured above). A commensal polychaete worm can sometimes be found here, as can the pea crab, Opisthopus transversus.

green sea anemone with embedded image of an aggregating anemone Sea Anemones

There are many anemones in the tide pools of the Pacific Northwest. One of the most common is the green anemone, Anthopleura xanthogrammica. Anthopleura is not just one species, however. Hidden within its tissues is an algae.

In this symbiotic relationship, the algae gain protection from snails and other grazers and don’t have to compete for living space, while the anemones gain extra nourishment from the algae in their guts. Contrary to popular opinion, this anemone’s green color is produced by the animal itself, not the algae that it eats.

Another fascinating anemone is the aggregating anemone (pictured in the embedded photo above), Anthopleura elegantissima, the most abundant anemone species found on rocky shores along the Pacific coast.

Aggregating anemones can rapidly clone themselves. If buried by shifting sands, they can survive for more than three months.

Tide Pool Guidebook 

You may not have the opportunity to explore a tide pool with a naturalist when you visit the Pacific Northwest Coast. In this case, you will want to find a guidebook or two to help you identify the diverse wildlife you will encounter.

One of the books we have at the marine life center that our visitors enjoy perusing when they have questions is The Beachcomber’s Guide to Seashore Life in the Pacific Northwest by J. Duane Sept. It was revised in 2009, it is beautifully illustrated and is a great guide to identifying the most common intertidal animals and plants of British Columbia, Washington, and Oregon.

The size is perfect to toss into your day pack if you wish to look up a specimen on your trek. It is written with the beachcomber in mind so while it does not feature every species, it is an excellent starting point for the more general specimens you may encounter.

While here, you may also be interested in Oregon Coast Quests – fun, educational, and clue directed hunts specific to the Oregon Coast.

simple graphic image of green grass on white background with text Nature Book ClubWelcome to the Nature Book Club Monthly Link Up. Devoted to connecting children to nature, the monthly link up will begin on the 20th day of each month. We welcome your nature book and activity related links. Read on for more details.

See all the great posts from The Nature Book Club’s co-hosts in June

The Nature Book Club is brought to you by these 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.

5 Senses at Sunset Walk from Barbara at Handbook of Nature Study
Discovering Nature in the Garden Scavenger Hunt from Jenny at Faith & Good Works
Nature Walk Alphabet Hunt from Emily at Table Life Blog
Guided Tide Pool Hike from Eva at Eva Varga
Foraging & Feasting Unit Study & Lapbook from Tina at Tina’s Dynamic Homeschool Plus
Fairy Gardens and Online Book Club from Dachelle at Hide The Chocolate
Decoupage Art with Nature Walk Findings from Katrina at Rule This Roost
Summer Nature Hike from Thaleia from Something 2 Offer
Leaf Shape Hunt from Karyn at Teach Beside Me

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

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!


Outdoor Pond Studies: Getting Started with Aquatic Sciences

Aquatic sciences include the study of wetlands, freshwater and marine aquatic systems, and their boundaries. Though we had a particularly dry winter, March has brought the rains – Yippee!  We took advantage of the blue skies one morning to do a little aquatic science of our own and explore the vernal ponds.

Vernal ponds or ephemeral pools, are temporary pools of water that provide habitat for distinctive plants and animals. They are considered to be a distinctive type of wetland usually devoid of fish, which thereby allow the safe development of juvenile amphibian and insect species.

pond studies

Pond Studies – Let’s Get Wet

The kids were very excited to explore this ecosystem.  Upon arrival, they dropped their journals and immediately waded into the water in search of critters.  The dominant organism observed was without a doubt the tadpole.  All the kids exclaimed that they wanted to bring home a few tadpoles and fortunately I brought along containers for each family.

The kids enjoyed the freedom to explore for about an hour.  We then gathered our collection tubs together to take a closer look at what we found.  I had hand lenses and a microscope on hand for those who wanted to observe the critters in more detail.  I loved that my kiddos pulled out their journals and began to illustrate what most interested them.

In addition to the tadpoles, we also observed several aquatic insects:  backswimmer larvae, mosquito larvae, water striders, and water boatman. We are looking forward to observing our catch more closely at home when there are fewer distractions.  Setting up an aquarium at home provides us with the opportunity to observe the critters more closely and thereby further our pond studies at home.

Looking for aquatic critters has always been one of our favorite activities when the weather warms.  Take a peak at one of our earlier excursions, Aquatic Critters: Summer Nature Study, and download a free dichotomous key to aquatic insects.

pond study printablesTake it Further – Inquiry Science

Upon visiting a pond, collect critter samples to bring home for an aquarium for closer observations over time. Use pond water to fill your aquarium, not tap water, because it contains the microorganisms plankton eat.  Any tap water added to account for evaporation should be first left uncovered overnight to allow the chlorine to vaporize.

I’ve created a free printable you may wish to use to record your observations: Download the Pond Studies Printable here.

** Remember that backswimmers and giant water bugs bite with a stinging effect and large dragonfly nymphs may also bite.

How would you set up an experiment to answer these experimental questions? Make a list of needed materials and write down a hypothesis before you begin.

  • If given a choice between open water and water filled with submerged plants, which animals choose the open water?
  • Do more prey survive when plants are present?
  • Will predators eat less of one particular type of prey if other prey are present as well?
  • Do pond animals have any preference between light and dark?
  • Does darkness affect the ability of the predators to catch the prey?
  • Where will algae and snails survive best, in the dark or in the light?

More Outdoor Learning Ideas

Ecology Explorations Curriculum For more ideas for ecology studies, Ecology Explorations is a wonderful collection of hands-on lessons and inquiry projects designed with the middle school student in mind.

Though it is a 10-week unit, you can pick and choose activities to according to interest or to tie into another curriculum study.

While exploring the pond, the kids will undoubtedly enjoy the squishing mud between their fingers and toes – I know I do! Combine playing in mud, and nature study with another hands-on science activity – making seed bombs with this tutorial from Dachelle.

Looking for more outdoor learning activities to inspire your children this season? Check out Rachel’s compilation of 24 Outdoor Learning Ideas.

A Mermaid’s Purse: A Surprise Discovery Within

Recently, as I was volunteering at a local marine life center, a pair of fishermen brought in a large mermaid’s purse as they called it – offering it to the center for educational purposes. Of course, the staff and volunteers jumped at the chance to showcase this animal in our aquaria.

I’m delighted that this recent discovery aligns with the current Nature Book Club theme – learn more about this monthly link-up below.

image of a mermaid's purse or egg case from a big skate

A mermaid’s purse is an egg case or capsule of oviparous (egg laying) sharks, skates, and chimaeras. The egg cases are purse-shaped with long tendrils at the corners that serve to anchor them to structures on the sea floor.

The size of egg cases vary, depending on species. Most contain a single embryo but egg cases of larger species, like the big skate, can contain seven. As it happens, the mermaid’s purse that was brought to us was that of the big skate, Raja binoculata.

Though I had previously observed skates and rays at larger aquaria (most notable Monterey Bay Aquarium and the Aquarium of the Pacific – both in California), I had yet to observe them in the wild. The director was eager to provide the students, volunteers, and many visitors the opportunity to observe the development of the embryos up close.

Skates & Rays

This recent experience has inspired me to learn more about the skates and rays. I immediately went to our local library and checked out a couple books to get me started – even as an adult, I often go to the children’s section to find non-fiction books on topics of interest. I love the way authors bring it down to their level and the two highlighted here do just that.

Raja binoculata photo by Scott Stevenson – visit his site for more amazing photographs

There are over 500 species of skates and rays in the world and are easily distinguished from other fish by their disc-shaped, dorso-ventrally (i.e. from top to bottom) flattened bodies and expanded pectoral fins which attach to the sides of the head.

Their basic body shape allows them to live on or very close to the bottom of the ocean, where they bury themselves in mud or sand to ambush prey and avoid predators. Along with their basic body shape, they are characterized by ventral gill openings, eyes and spiracles located on the top of the head, pavement-like teeth, and lack of an anal fin.

Skates and Rays is a great book for children to introduce them to the subject. Any beachcomber who finds a “mermaid’s purse,” an egg case from a skate, must wonder what sort of creature can emerge from such a curiously shaped item. This book, part of the “Living Ocean” series, explores the world of rays and skates, of which there are more than 150 species.

Closely related to sharks, these animals make up a subclass of cartilaginous fish. Instead of having skeletons made of bone, elasmobranchs have skeletons made of soft, pliable cartilage. Like rays, skates are usually flat, with a long tail.

This book examines the behavior, habitats, and anatomy of these intriguing swimmers, describing how they catch prey, why they are important to oceans, and why many are in danger.

Another good choice is The Nature Company Guide to Sharks & Rays. This book has real photographs of sharks on every page, and rays are featured more prevalently than in most other books on the same topic. The species is clearly identified and portrayed in the field guide chapters, and following that are details about choice diving locales around the world.

It will be especially useful to the teen reader or marine naturalist/hobbyist. The information is well organized, detailed, and scientifically accurate. For someone less familiar with scientific terms, it could be a bit heavier, as it tends to use many terms, such as pelagic and elasmobranch, with only a brief definition provided.

A Mermaid’s Purse

Egg cases are made of collagen protein strands and most would describe the exterior texture as rough and leathery. Some egg cases have a fibrous material covering the outside of the egg case, thought to aid in attachment to substrate.

Egg cases without a fibrous outer layer can be striated, bumpy, or smooth and glossy. Egg cases are typically rectangular in shape with projections, called horns, at each corner. Depending on the species, egg cases may have one or more tendrils.

The mermaid’s purse that was brought into the learning center was prepared by one of the graduate student volunteers from the university. He carefully cut a hole into the flat side of the egg case and adhered a clear plastic covering. This provided a window by which we can watch the development of the embryos within as you can see from the video above.

Raja binoculata

The big skate is the largest species of skate (family Rajidae) in the waters off North America. They are found all along the Pacific coast from Alaska to Baja California, typically from the intertidal zone to a depth of 120 m (390 ft).

These impressive animals feed on benthic invertebrates and small fishes. As I stated previously, they are unusual among skates in that their egg cases may contain up to seven eggs each. This species is one of the most commercially important skates off California and is sold for food, though compared to other commercial fisheries, it is of only minor importance.

Typically caught as a by-catch of trawlers, fisheries have begun to market it more as a result of higher market value. Unfortunately, the big skates’ slow reproductive rate gives cause for some concern but population data is limited.

simple graphic image of tree with text The Nature Book Club

Welcome to the The Nature Book Club Monthly Link Up. Devoted to connecting children to nature, the monthly link up will begin on the 20th day of each month.

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

See all the great posts from The Nature Book Club’s co-hosts in April:

The Nature Book Club is brought to you by these 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.

Bird Nest/Eggs nature study pages from Barb at Handbook of Nature Study

Eggs: Nature’s Perfect Package from Erin Dean at the Usual Mayhem

Getting Started with Citizen Science – Nest Watch from Eva Varga

From Egg to Sea Turtle Unit Study & Lapbook from Tina’s Dynamic Homeschool Plus

Eggs Nature Study Free Printable Word Search from Faith and Good Works

Egg Scavenger Hunt with Egg Carton from Katrina at Rule This Roost

Felt Bag Handicraft from Melanie at Wind in a Letterbox

Clay Eggs Project from Emily at Table Life Blog

Online Book Club from Dachelle at Hide the Chocolate

Egg Identification Nature Bingo {Free Printable} from Cassidy at Freshly Planted

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


Oregon Nature Quiz #3: Winter Wonderland Edition

Winter is finally upon us and snow is swirling everywhere. Over the past couple of weeks, my VIPKID students have been sharing photos of the snowmen they have built and I have lamented that we have nothing but rain here on the Oregon coast. On President’s Day, however, we woke up to a light dusting of snow and intermittent snowfall throughout the day. What fun!

Oregon Nature Quiz #3: Winter Wonderland Edition

It’s been a while since my last nature quiz — and the new snow has brought inspiration. Here are five of the photos showing evidence of wildlife action in the depth of winter (albeit not all in the snow). Can you identify the wildlife represented here?

image of a girl with her hands in the shape of a heart around the base of a tree covered with ladybugs with text: Nature Quiz #3 @EvaVarga.netimage of a pine cone eaten by a squirrel with text Nature Quiz #3 @EvaVarga.netimage of cougar track in mud with text nature quiz #3 @EvaVarga.netimage of bird track in snow with text nature quiz #3 @evavarga.netimage of rabbit tracks in snow with text: nature quiz #3 @EvaVarga.net

Answers:

1. When we lived in Redding, one of our most anticipated nature outings was our annual ladybug hike. It was always fascinating to see the ladybugs hibernating – hundreds of thousands of ladybugs all gathered in one place. Ladybirds hibernate through the winter as adult insects. Different species will usually hibernate in different places; some shelter under tree bark, others sleep under leaf litter, etc. Have you oberseved ladybugs hibernating in a similar fashion? Some will even gather around window crevices, buildling siding, and wooden structures.

image of ladybugs hibernating on bark of tree with text nature quiz #3 @evavarga.net

Close up image of the laybugs in the bark crevices of a Ponderosa Pine (Pinus ponderosa).

2. The cone of a Pinus ponderosa that has been broken apart by a squirrel for the nuts. Most recently, my daughter has given the art of taxidermy a try. A squirrel was her first specimen – results have not yet been reported.

3. Pictured here is a cougar (Puma concolor) track in the mud. Native to Oregon, cougars range throughout the state, the highest densities occur in the Blue Mountains in the northeastern part of the state and in the southwestern Cascade Mountains. This photo was taken in the coastal range while we were hanging buckets for sugaring time. Cougars are territorial animals and maintain home ranges of up to 100 miles. Most active at dawn and dusk, cougars are lone hunters. They are generally solitary animals, except for mothers who remain with kittens for about two years.

Learn more about The Science of Sugaring (tapping maple trees to collect the sap to make maple syrup).

4. There were no other nearby tracks so I am not certain, but I believe these bird tracks may be eagle simply due to their size. What do you think? When we lived in Redding, we loved to watch the resident eagles near the Sundial Bridge. The bald eagle (Haliaeetus leucocephalus), our national bird, is the only eagle unique to North America. It’s scientific name signifies a sea (halo) eagle (aeetos) with a white (leukos) head. At one time, the word “bald” meant “white,” not hairless. Bald eagles are found throughout most of North America, from Alaska and Canada to northern Mexico – with about half living in Alaska. The northwest coast is by far their greatest stronghold for bald eagles. They flourish here in part because of the salmon. Dead or dying fish are an important food source for all bald eagles.

Read my earlier post on Exploring Animal Tracks and learn how to use tracks to tell a story. Make animal track stencils and get out fabric paints to decorate t-shirts.

5. Did you guess rabbit? Six species of rabbit like mammals (these include, rabbits, pikas, and hares) can be found in various habitats throughout central Oregon where this photograph was taken. These small mammals feed primarily on grasses and forbs, have at least two litters per year, and are usually found where there are good amounts of concealing cover available. The shrubs under which they take cover are an important food source and conversely, they serve as the primary prey for many carnivores.