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Where to Buy:

Bookshop

Overview:

Award-winning author and photographer Nic Bishop brings his vast knowledge of biology to this eye-catching exploration of butterflies and moths. With breathtaking full-page images, Nic introduces young readers to the beauty and diversity of these amazing insects, and their similarities and differences.

Genre:

Non-fiction

Grade-Level:

3rd

Readability:

Approaching Grade Level

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Where to Buy:

Amazon

Overview:

An incredible true story of friendship between the author and an octopus named Athena. This book has many themes, and one of them is the similarities and differences between humans and octopi.

Genre:

Book/Non-Fiction

Grade-Level:

4th-5th

Readability:

At Grade Level

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Where to Buy:

Amazon

Overview:

This book tells the story of Jane Goodall and her groundbreaking research with chimpanzees in Tanzania. The problem in this story is the lack of understanding of chimpanzee behavior, and the solution is Jane Goodall's observational studies, which revolutionized our understanding of these animals.

Genre:

Book/Non-Fiction

Grade-Level:

3rd-4th

Readability:

Approaching Grade Level

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Overview:

In this video you'll learn the similarities differences between house cats and tigers.

Genre:

Book/Non-Fiction

Grade-Level:

2nd-3rd

Readability:

Approaching Grade-Level

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What's the difference between a house cat and a tiger? Learn more about Big Cat Rescue: http://bigcatrescue.org Cole & Marmalade: https://www.youtube.com/user/chrispoole20 BIG CAT TV is a close look into our day-to-day operations, the conservation efforts we support, and the 100+ feline residents of "Big Cat Rescue" in Tampa, FL. USA.

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The text discusses aspects of the topics that are similar, as well as what about the topics are different.

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Where to Buy:

Amazon

Overview:

In "Nic Bishop Frogs: Amazon Adventure," Bishop takes readers on a journey to the Amazon rainforest to explore the fascinating world of frogs. The book provides detailed information about different species of frogs found in the Amazon, their habitats, behaviors, and unique adaptations.

Genre:

Book/Non-Fiction

Grade-Level:

3rd-4th

Readability:

Approaching Grade Level

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Where to Buy:

Amazon

Overview:

A visually stunning book that introduces readers to some of the most fascinating and unique animals on the planet. Each page is filled with facts and life-sized illustrations of animals, making learning engaging and fun.

Genre:

Book/Non-Fiction

Grade-Level:

3rd

Readability:

Approaching Grade Level

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Where to Buy:

Amazon

Overview:

This book tells the story of a young hippopotamus named Owen who forms an unlikely bond with a 130-year-old tortoise named Mzee after being separated from his family by a tsunami. The problem in this text is Owen's separation from his family, and the solution is the friendship he finds with Mzee.

Genre:

Book/Non-Fiction

Grade-Level:

4th

Readability:

Approaching Grade Level

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Overview:

Learn how today's big cats evolved from prehistoric cat-like organisms, and what factors contributed to their evolution.

Genre:

Video/Non-Fiction

Grade-Level:

6th-9th

Readability:

Advanced

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Learn how today's big cats evolved from prehistoric cat-like organisms, and what factors contributed to their evolution.

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1. What are some of the differences you notice between the five different text structures?

2. How do we distinguish between an informational text and a fictional text?

3. Can you think of any of your own examples of books or videos that you have seen that represent any of these categories?

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Article: Invasive Species - Finding Solutions to Stop Their Spread

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Article: Invasive Species - Finding Solutions to Stop Their Spread

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Overview:

This article gives information about different invasive species around the United States and ways to combat them.

Genre:

Article/Non-Fiction

Grade-Level:

8th-10th

Readability:

Advanced

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U.S. Fish and Wildlife Service biologist holds a bighead carp. Photo by R. Hagerty, U.S. Fish and Wildlife Service.

Some are sharp, some are spotted and some are slithery, but all invasive species are bad for public lands. Invasive species are nonnative organisms whose introduction to a particular ecosystem can cause economic or environmental harm, or harm to human, animal or plant health.

Some nonnative species don't cause harm (They're not "invasive"), but those that do can cost billions in damage and disrupt an environment's natural balance.

National Invasive Species Awareness Week is an international event to raise awareness about invasive species, the threat that they pose, and what can be done to prevent their spread.

No matter where they came from, how they got here or what harm they cause, invasive species are a serious concern for all who protect and preserve America's public lands and waters.

Invasive Mussels

Quagga and zebra mussels are invasive species from Eurasia's Caspian Sea. These tiny mollusks reproduce rapidly and attach to surfaces such as pipes, lake bottoms, docks and break walls, forming a crust of shells. Infestations in dams and water treatment facilities can impact the delivery of water and power. Large colonies in lakes and waterways affect freshwater ecosystems, leading to harmful effects on native and endangered species, including recreational game fish. Mussel infestations may impact recreation in other ways, from sharp shell fragments scattered over beaches to increased requirements and cost for boat inspection and decontamination.

What are we doing to address invasive mussels?

Since their discovery in the Great Lakes in the 1980s, Interior's bureaus and partners have worked to prevent, contain and control invasive mussels. Some of the efforts to limit their spread include:

Watercraft inspection and decontamination

Monitoring

Rapid response

Public education

Research on detection and control measures

Partnership networks are leveraging what has been learned since the initial mussels invasion. For example, the Quagga and Zebra Mussel Action Plan for Western U.S. Waters is a blueprint for actions to protect the uninfested West from mussels and other aquatic invasive species. In the Great Lakes Region, the Invasive Mussel Collaborative connects people, science and management to advance technology for invasive mussel control.

Get Involved

Invasive mussels primarily spread by hitching rides on boats and other watercraft. Preventing the spread of invasive mussels starts with you! Remember to   clean, drain and dry your watercraft after leaving the water. With your help, we can protect the nation's waterways and wildlife.

Rapid ʻŌhiʻa Death

ʻŌhiʻa -- the most abundant native tree in Hawai'i -- is both culturally significant and ecologically valuable. Sadly, ʻŌhiʻa are now threatened by two invasive fungal pathogens that cause Rapid ʻŌhiʻa Death (ROD), a serious threat to native forests in the Hawaiian Islands. Unfortunately, the future of the ʻŌhiʻa tree is in doubt. Hundreds of thousands of ʻōhiʻa have already died due to this fast-acting disease.

What are we doing to address Rapid ʻŌhiʻa Death?

Federal and non-federal partners are undertaking actions in the 2020-2024 Rapid Ōhiʻa Death Strategic Response Plan which describes the needs for emergency response as well as for the long-term health of Hawai'i's forests. Our understanding of the disease and the microscopic fungi that cause it has improved through significant investments in research, remote sensing and field studies. Management measures such as selective cutting of infected trees, sealing wounds on infected trees, fencing to exclude ungulates and biosanitation protocols to minimize the spread of fungal spores all help to address the spread and severity of this devastating disease.

Get Involved

Whether living in or visiting the Hawaiian Islands, be aware of Rapid ʻŌhiʻa Death and follow biosecurity protocols that are in place (e.g., don't move ʻōhiʻa, avoid injuring the tree, clean your shoes and gear and wash your vehicle) to reduce the spread of this disease.  Learn more about Rapid ʻŌhiʻa Death so that we can identify and support solutions.

Invasive Carp: Bighead, Silver, Black and Grass Carp

Finding their way into America's rivers and lakes, invasive carp (bighead, silver, black and grass carp) threaten recreational, commercial and subsistence fisheries worth billions of dollars annually. These aquatic invaders take over habitat and threaten native species, and impact recreational boating and other activities important to the livelihood of many communities.

What are we doing to address invasive carp?

Interior experts provide key leadership, research and tactical assistance across the Great Lakes, Upper Mississippi River and Ohio River basins. By developing the "Management and Control Plan for Bighead, Black, Grass, and Silver Carps in the United States," we can use it as a national blueprint on the management of invasive carp. We've been developing critical new technologies to combat the threat posed by all invasive carp life stages (eggs, larvae, juveniles and adults) and working with natural resource managers to improve early detection and rapid response activities.

Get Involved

Everyone can play a role in preventing the spread of invasive carp. Ways you can help:

Learn to identify juvenile invasive carp

Only use wild-caught bait fish in waters where they came from

Don't move live fish from one location to another

Drain lake or river water from live wells and bilges before moving your watercraft

Finally, become an ambassador for your watershed and  help others learn how to help!

Invasive Rodents

Invasive house mice cause injury to nesting birds like this injured Laysan albatross at Midway Atoll National Wildlife Refuge. Photo by U.S. Fish and Wildlife Service.

Invasive rodents on islands cause serious impacts to both native biodiversity and infrastructure. These harmful rodents, such as mice and rats, prey upon and compete with native wildlife, reducing native biodiversity and sometimes leading to the extinction of a species. Rodents damage buildings by chewing through wood and insulation and gnawing on wiring which can trigger fires. Islands represent some of the greatest concentration of biodiversity, with island species often being evolutionarily distinctive. Unfortunately, these species are often highly vulnerable to novel disturbances, particularly invasive rodents.

What are we doing to address invasive rodents on islands?

Interior works with a variety of partners on invasive rodent prevention and eradication. The main goal is to prevent rodents from reaching new islands. Where already found, invasive rodents are eliminated to limit their impact on native species and infrastructure. Helicopter dispersed rodenticide is used to completely eradicate rodents from islands. Successful rat eradications can lead to amazing native restoration stories. For example, a rat eradication at Desecho National Wildlife Refuge in the Caribbean enabled seabirds, the island's endemic lizards, three endemic arachnids, and the federally threatened higo chumbo cactus to thrive once again.

Get Involved

Whether you're traveling or supporting island conservation, here are a few ways to help:

Prevent invasive rodents from reaching new islands (i.e., using rat guards on boat mooring lines)

Spread the word on how devastating rodents can be for native species on islands

Learn more about rat eradication and island restoration

Invasive Plants

Today, noxious weeds and other invasive plant species infest more than 80 million acres of Interior-managed public lands, and they continue to spread. This presents multiple impacts to threatened ecosystems. For example, downy brome (cheatgrass), infests 50 million acres and provides fuel to wildfires that burn across increasingly larger areas. And in a devastating one-two punch, cheatgrass can quickly re-establish itself on burned lands, outcompeting native grasses and increasing the extent of infestation.

What are we doing to address invasive plants in the West?

Interior is responsible for preventing and controlling invasive plants on the lands that we manage. We prioritize invasive species projects to protect the most critical resources - such as stream corridors or greater sage-grouse habitat. We work with numerous partners to support effective all-lands inventory, treatments and monitoring. Within Interior, the Invasive Species and Wildland Fire Management programs are also working together to address the dual threats of invasives and wildfires to our communities, natural landscapes and cultural resources.

Get Involved

Prevention is key, so identifying invasive plant species is crucial. Helping with early detection, rapid response and public awareness is also important. Report invasive plant infestations to your local Interior bureau field offices.

Preventing the Next Invasive Species

Once an invasive species becomes established, it is rarely possible to eradicate. The best way to avoid the harm that invasive species can cause is to prevent them from entering the country.

We use several ways to predict species at risk of becoming invasive and then preventing them from being imported if possible. By monitoring and inspecting wildlife imported into the United States at designated wildlife ports we can intercept problematic species.

Get Involved

You can be involved in prevention in various ways. Please keep your pets secure and do not release them-under any circumstances. Animals like exotic fish and reptiles can wreak havoc on native wildlife and habitat when they escape or are released. If you must surrender a pet because you can no longer care for it, do so responsibly. Other excellent sources for how to prevent the spread of invasive species include:

The Power of Partnerships

Invasive species may be widespread and vastly different, but luckily so are the methods and teams protecting public lands. The Department of the Interior is forging strong partnerships with others to collectively address the threat of invasive species. Our 2021-2025 Invasive Species Strategic Plan charts a path forward. We can't do it alone. Together, success is possible!

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Invasive Species: Finding solutions to stop their spread | U.S. Department of the Interior

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No matter where they came from, how they got here or what harm they cause, invasive species are a serious concern.

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Overview:

Horses are considered to be truly unique animals that have conquered the world with their beauty. Each equine representative is individual and each one requires a personal approach. Horses are widespread all over the world due to the fact that they have adapted to various types of climate, and as a result, new breeds of horses have emerged with a different thickness of the mane, coat colors, and character.

Genre:

Video/Non-Fiction

Grade-Level:

5th

Readability:

At Grade Level

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All about Horses: Collection of Fun Facts and Equine Videos for e-Learning

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The description text structure describes or explains a topic, idea, person, place, or thing to give the reader a mental picture.

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Video: Introduction to Informative Texts

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Video: Introduction to Informative Texts

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Overview:

An introduction to what an informational text is, what it consists of, and how to distinguish one from a fictional text.

Genre:

Video/Non-Fiction

Grade-Level:

2nd-4th

Readability:

Approaching Grade Level

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Video: Introduction to the Five Text Structures

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Video: Introduction to the Five Text Structures

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Overview:

An introduction to the five different text structures; compare and contrast, problem and solution, sequence, cause and effect, and description.

Genre:

Video/Non-Fiction

Grade-Level:

5th-6th

Readability:

At Grade Level

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The structures of informational texts | Reading | Khan Academy

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Article: Cats may Understand Cause and Effect

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Article: Cats may Understand Cause and Effect

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Overview:

This article discusses results from a study that shows correlation between cats and cause and effect.

Genre:

Article/Non-Fiction

Grade-Level:

6th-8th

Readability:

Advanced

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Science is getting closer to proving that yes, your cats are probably smarter than you. According to a study from researchers in Japan, cats seem to understand physics and cause and effect.

To do that, the researchers studied 30 domesticated cats, and videotaped their reactions to different scenarios. If you've ever had a cat, you've probably watched them react excitedly to a shaken bag of treats. The researchers in Japan have created a similar scenario by shaking a container in front of the cats. In one scenario, the container rattles and then an object is dropped from the container. In another, the container makes no noise and no object drops. These two are generally congruent with the laws of physics: the sound signals to the cat that there is something inside. And the cats reacted appropriately, staring longer at the container that made a sound.

Then, the researchers switched things up: The container that rattled didn't drop an object, and the container that didn't rattle did produce something. This also inspired the cats to stare longer, which the researchers suggest could mean it doesn't fit into the cats' understanding of a logical cause and effect scenario.

Previously, it was believed that cats had an "unsophisticated" understanding of causal relationships. But, this research and its focus on the auditory response of cats show that cats can predict the presence of objects, and even have a grasp of what gravity is. And future research that uses more complex scenarios could help researchers better understand what the sound is telling cats to expect in terms of quantity or size of objects.

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Cats May Understand Cause And Effect, Study Finds

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Researchers in Japan have tested cats' skills at predicting whether an object would appear based on auditory clues.

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Overview:

An online lecture discussing the dynamics between predators and prey. The presence of predators may cause prey to exhibit certain behaviors. An increase of prey may lead to higher predator numbers due to amount of food.

Genre:

Video/Non-Fiction

Grade-Level:

8th

Readability:

Advanced

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Overview:

This article discusses the process by which honey is made.

Genre:

Article/Non-Fiction

Grade-Level:

5th-6th

Readability:

At Grade-Level

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Why do bees make honey?

Honey bees collect nectar to create honey and store as food because it provides the energy for bees' flight muscles and provides heating for the hive in the winter. Fortunately, honey bees will make more honey than the colony needs, so it is necessary for beekeepers to harvest the excess, which they bottle.

Made Naturally by Nature

From Bee

Honey starts as flower nectar collected by bees, which gets broken down into simple sugars stored inside the honeycomb. The design of the honeycomb and constant fanning of the bees' wings causes evaporation, creating sweet liquid honey. Honey's color and flavor vary based on the nectar collected by the bees. For example, honey made from orange blossom nectar might be light in color, whereas honey from avocado or wildflowers might have a dark amber color.

To Hive

On average, a hive will produce about 55 pounds of surplus honey each year. Beekeepers harvest it by collecting the honeycomb frames and scraping off the wax cap that bees make to seal off honey in each cell. Once the caps are removed, the frames are placed in an extractor, a centrifuge that spins the frames, forcing honey out of the comb.

To Home

After the honey is extracted, it's strained to remove any remaining wax and other particles. Some beekeepers and bottlers might heat the honey to make this process easier, but that doesn't alter the liquid's natural composition.

After straining, it's time to bottle, label, and bring it to you. It doesn't matter if the container is glass or plastic, or if the honey is purchased at the grocery store or farmers' market. If the ingredient label says "pure honey," nothing was added from bee to hive to bottle.

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Why do bees make honey? Honey bees collect nectar to create honey and store as food because it provides the energy for bees' flight muscles and provides heating for the hive in the winter. Fortunately, honey bees will make more honey than the colony needs, so it is necessary for beekeepers to harvest the excess, which they bottle.

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Video: How does Climate Change Affect Animals

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Video: How does Climate Change Affect Animals

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Overview:

Learn the ways the global issue of climate change is affecting all animals in different aspects.

Genre:

Video/Non-Fiction

Grade-Level:

5th

Readability:

At Grade Level

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How does climate change affect animals? | Global Ideas

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Article: How Overfishing Threatens the World's Oceans

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Article: How Overfishing Threatens the World's Oceans

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Overview:

Decades of harvesting the sea of its fish has disrupted the ocean ecosystems and all who live in them.

Genre:

Article/Non-Fiction

Grade-Level:

8th-9th

Readability:

Advanced

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Scientists have long been sounding the alarm about a looming catastrophe of ocean overfishing-the harvesting of wildlife from the sea at rates too high for species to replace themselves. Yet for two decades, global leaders have been at an impasse in their efforts to reverse the damage that has been done.

Marine scientists know when widespread overfishing of the seas began. And they have a pretty good idea when, if left unaddressed, it will end badly. Here's a look at the critical issues in overfishing-from its effects on biodiversity to the limited successes of mitigation efforts.

Why overfishing occurs

The earliest overfishing occurred in the early 1800s when humans, seeking blubber for lamp oil, decimated the whale population around Stellwegen Bank, off the coast of Cape Cod. Some fish consumed in the United States, including Atlantic cod, herring, and California's sardines, were also harvested to the brink of extinction by the mid-1900s. These isolated, regional depletions were highly disruptive to the food chain-which only became more precarious in the late 20th century.

In the mid-20th century, countries around the world worked to build their fishing capacities to ensure the availability and affordability of protein-rich foods. Favourable policies, loans, and subsidies spawned a rapid rise of big industrial fishing operations, which quickly supplanted local fishers as the world's main source of seafood.

These large, profit-seeking commercial fleets were aggressive, scouring the world's oceans and developing ever more sophisticated methods and technologies for finding, extracting, and processing their target species. Consumers soon grew accustomed to having access to a wide selection of fish at affordable prices.

But by 1989, when about 90 million tonnes (metric tons) of fish were taken from the ocean, the industry had hit its high point, and yields have declined or stagnated ever since. Fisheries for the most sought-after species, like orange roughy, Chilean sea bass, and bluefin tuna, have collapsed for lack of fish. In 2003, a scientific report estimated that industrial fishing had reduced the number of large ocean fish to just 10 percent of their pre-industrial population.

How overfishing affects biodiversity

Faced with the collapse of large-fish populations, commercial fleets began travelling deeper in the ocean and farther down the food chain for viable catches. This so-called "fishing down" has triggered a chain reaction that is upsetting the ancient and delicate balance of the sea's biological system.

Coral reefs, for example, are particularly vulnerable to overfishing. Plant-eating fish keep these ecosystems in balance by eating algae, keeping the coral clean and healthy so that it can grow. Fishing out too many herbivores-whether intentionally or as bycatch-can weaken reefs and make them more susceptible to being ravaged by extreme weather events and climate change. Fishing equipment and debris can also physically destroy the fragile corals that make up the reef foundations.

Overfishing can also harm other marine species. Trawling, a method in which boats pull massive nets behind them in the water, pulls in more than just shrimp and bluefin tuna-it captures just about anything in its path. Sea turtles, dolphins, sea birds, sharks, and other animals have all faced existential threats as bycatch.

Efforts to prevent overfishing

Over the years, as fisheries have caught less and less, humans have begun to understand that the oceans, assumed to be unendingly vast and rich, are in fact highly vulnerable. In 2006, a study of catch data published in the journal Science grimly predicted that if such unsustainable fishing rates continue, all the world's fisheries will collapse by 2048.

Many scientists say most fish populations could be restored with aggressive fisheries management and better enforcement of laws governing catches, including instituting catch limits. An increased use of aquaculture, the farming of seafood, would also help. And in many regions, there is reason for hope.

Still, many challenges remain. About a third of global stocks are overfished-and the overall proportion of fish stocks at sustainable levels has continued to decline. The FAO report says this deterioration of fish stocks can particularly be seen "in places where fisheries management is not in place, or is ineffective." Of the areas the organisation monitors, the Mediterranean and Black Sea had the highest percentage of stocks-62.5 percent-fished at unsustainable levels.

Can we stop overfishing?

Government subsidies to the fishing industry remain a significant challenge to reversing this troubling trend. One global survey found that in 2018 nations spent £16 billion on so-called harmful subsidies that fuel overfishing-a 6 percent rise from 2009.

As National Geographic reported at the time, harmful subsidies are those that fund practices that would not otherwise be profitable, such as for industrial trawlers' fuel costs. China, for example, has increased its harmful subsidies by 105 percent over the past decade.

World Trade Organisation members have been discussing how to limit these subsidies since 2001-with little progress. And despite a pledge by members of the United Nations to forge an agreement by 2020, that deadline has passed with no resolution.

In 2021, WTO Director-General Ngozi Okonjo-Iweala called on members to reach an agreement, arguing that a "failure to do so would jeopardise the ocean's biodiversity and the sustainability of the fish stocks on which so many depend for food and income."

It's unclear whether countries will muster the political will to follow through. But what is clear to scientists is that it is one of many measures that's critical to saving the world's oceans.

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How overfishing threatens the world's oceans-and why it could end in catastrophe

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Decades of harvesting the seas have disrupted the delicate balance of marine ecosystems-despite global efforts to mitigate the damage.

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Overview:

This article discusses the migratory bird cycle, and what each phase of the cycle consists of.

Genre:

Article/Non-Fiction

Grade-Level:

5th-6th

Readability:

At Grade-Level

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Smithsonian's National Zoo and Conservation Biology Institute

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To illustrate the full annual cycle of migratory birds, we will take a closer look at the gray catbird. The gray catbird is a songbird that is common to wild areas, suburbs and cities across most of the continental United States during the spring and summer months. These birds are called catbirds, because their distinct call sounds a bit like a cat's meow. When singing, the gray catbird is a mimic-its song is a collection of sounds it has heard throughout its life. Catbirds can be found in many different habitats, so scientists at the Smithsonian Migratory Bird Center have been closely studying catbirds for more than 20 years in the Washington, D.C., metropolitan area. They have used many of the tracking technologies you will explore in this set of lessons to research the gray catbird's annual cycle.

Breeding

Catbirds begin arriving in Washington, D.C., in late April and early May. When they first arrive, there are a lot of catbirds, and the city is full of their songs. Many of the catbirds we see live far north of the city and are just stopping through during their migration. Within a week or two, only the birds that will stay for the whole summer are left in the area. The catbirds that are still here use their songs to stake out territories for building nests.

Female catbirds build their nests in dense shrubs using thin twigs and grasses. They often weave bits of colorful plastic they find into their nests. Once the nest is complete, the female will lay one to six bright, turquoise-green eggs in the nest. She incubates the eggs, sitting on them to keep them warm, for about two weeks. During this time she has to spend most of her time on the nest, so she is vulnerable to predators. When the eggs hatch, the nestlings (birds that have hatched but have not left their nest) emerge helpless with closed eyes and no feathers. Both parents quickly get to work feeding the nestlings. The parents and young feed on a variety of insects during this time, especially caterpillars. This high-protein diet is necessary, because the nestlings have to grow to the same size as their parents before leaving the nest-a period of less than two weeks!

Once the nestlings are big enough and have grown the feathers they need to fly, they leave the nest. This process is known as fledging. At this point, the young catbirds are called fledglings, and they will join their parents in a hunt for insects to eat. The fledglings are still very weak and need to gain a lot of weight to survive. They are also not great flyers yet and are just beginning to get used to the new world they have launched into. This makes fledglings an easy target for predators, especially outdoor cats, which often spend time hunting for birds in suburban gardens. Most of the fledglings won't survive for more than one week. After a few more weeks when they are strong enough, the fledglings that survive will leave their parents to explore their surroundings.

Migration

The environment changes a lot over the course of the summer. Catbirds must shift their diet with the changing season to get ready for migration. By the end of the summer, there are fewer caterpillars and other insects to eat. Luckily, the plants that flowered in spring and early summer will begin to produce berries. Adding fruit to their diet helps catbirds gain a lot of weight in the form of fat. This fat acts like a rechargeable battery during the catbirds' migration-the energy they get from the food that they eat is stored in the fat and provides the power for their migratory journey.

Based on tracking data, including light-level geolocator tags, we know that catbirds from different breeding grounds make their fall migration to different locations. The routes the birds take during migration also differ, even among birds that leave from the same breeding location. For example, some of the catbirds we have tracked from Washington, D.C., followed the Atlantic coastline, while others traveled along the foothills of the Appalachian Mountains-a long mountain chain that runs from Georgia to Maine.

The amount of time birds spend migrating also varies by individual. Some of the birds we have tracked have taken several weeks to complete their journey, while others make the trip in less than one week. Some catbirds even stop for a long time before completing their migration. One of the birds we tracked stopped in the Appalachian Mountain foothills for more than a month before continuing its journey!

Overwintering

Using tracking data, we have found that catbirds in Washington, D.C., mostly travel to Florida and Cuba. Tracking data has shown that catbird populations from the midwest and western United States travel to the southern coast of the United States and to Mexico.

The gray catbirds' winter habitats are very similar to the habitats where they spend their summers. Most of the catbirds we have tracked overwinter in habitats with a lot of shrubs. These habitats tend to have a lot of cover to help catbirds avoid predators and a lot of berry-producing plants and insects to supply catbirds with food. If catbirds stayed in the north over the winter, their food supply would be very limited and most of them would not survive.

The climate in areas where catbirds overwinter tends to be mild and comfortable, because it is closer to the equator than the areas where they breed. By spending the winter in the south, the catbirds are not exposed to the dangerous cold of northern winters.

As spring approaches, the catbirds start to become restless. Their sleep cycles change, and they start foraging for food later in the day. The catbirds gain a lot of weight again, this time to power their migration back north. If they stayed healthy through the winter, stored enough energy in the form of fat and survive their journey north, they will return to their summer range to breed.

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The Full Annual Cycle of Migratory Birds

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Learn about the full annual cycle, which describes a migratory bird's ecology across the year, including breeding, migration and overwintering periods.

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The problem and solution text structure sets up a problem or problems, explains the solution, and then discusses the effects of the solution.

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Overview:

This article talks about the steps spiders take in order to create their webs!

Genre:

Article/Non-Fiction

Grade-Level:

5th

Readability:

At Grade-Level

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Spiders are skillful engineers, gifted with amazing planning skills and a material that allows them to precisely design rigorous and functional webs.

The material-spider silk-has chemical properties that make it lustrous, strong and light. It's stronger than steel and has impressive tensile strength, meaning it can be stretched a lot before it snaps. Scientists have been trying for decades to decode exactly what gives the silk both strength and elasticity, but so far they have found only clues.

Any individual spider can make up to seven different types of silk, but most generally make four to five kinds, says Jonathan Coddington, director of the Global Genome Initiative and senior scientist at the Smithsonian's National Museum of Natural History.

Spiders use their silk for several purposes, including web-building. That diversity is not hard to imagine, given that Earth hosts 45,749 species of spiders, according to the World Spider Catalog. The number is changing constantly with the frequent discovery of new species.

Why build webs? They serve as "pretty much offense and defense," says Coddington. "If you're going to live in a web, it's going to be a defensive structure," he says, noting that vibrations in the strands can alert the spiders to predators. Webs are also used to catch prey, says Coddington, whose research has focused in part on spider evolution and taxonomy.

Sometimes spiders eat their own webs when they are done with them, as a way to replenish the silk supply.

Spider silk is made of connected protein chains that help make it strong, along with unconnected areas that give it flexibility. It is produced in internal glands, moving from a soluble form to a hardened form and then spun into fiber by the spinnerets on the spider's abdomen.

Spiders' multiple spinnerets and eight legs come in handy for web-building. The architecture of a web is very species-specific, says Coddington. "If you show me a web, I can tell you what spider made it," he says, adding that spiders "are opinionated" about where they will make a web. Some might be at home in the bottom of a paper cup, while others wouldn't touch that space.

Most web-building happens under the cover of darkness.

The typical orb weaver spider (the group that's most familiar to Americans) will build a planar orb web, suspended by seven guy lines attached to leaves, twigs, rocks, telephone poles or other surfaces. Hanging from a leaf or some other object, the spider must get its silk from that point to the other surfaces.

The spider starts by pulling silk from a gland with it fourth leg. The opposite fourth leg is used to pull out multiple strands of silk from about 20 additional silk glands, creating a balloon-like structure. The spider sits patiently, knowing that eventually a warm breeze will take up the balloon, which carries away the first line of silk.

Eventually the balloon's trailing silk strand snags-and, like an angler with a fish on the line, the spider can feel the hit. It tugs to make sure the silk strand is truly attached, then it pulls out new silk and attaches the strand to whatever it is perched on and starts gathering up the snagged strand, pulling itself towards the endpoint, all the while laying out new silk behind it. That new silk is the first planar line. The spider may do this 20 times, creating a network of dry (not sticky) silk lines arcing in all directions.

The spider then has to determine which of those lines constitute seven good attachment points-they must be in a plane and "distributed usefully around the circle the web will occupy," says Coddington. The spider cuts away the 13 lines that it won't use. "Now that you have the seven attachments you need, you no longer need to touch the ground, leaves, twigs, anything ... you are in your own, arguably solipsistic, world."

Then the spider starts to spin its web, a relatively simple and predictable process. It begins at the outside and works its way in, attaching segment by segment with its legs, creating concentric circles and ending with a center spiral of sticky silk that traps much-needed prey-all the energy invested in making the web depletes protein stores.

The sticky stuff merely immobilizes the prey. The coup de grâce comes from the spider's jaws. "Most spiders attack with their teeth," says Coddington. "They just wade in and bite the thing to death." That's a risky proposition, though, because the prey might not be entirely stuck.

A few families of spiders have developed an alternative mode of offense: the sticky-silk wrap attack. Those spiders lay a strand of sticky silk across the ground. When an insect crosses, the vibration alerts the spider, which then attacks, flicking lines of sticky, strong silk around the insect and wrapping it up until it is fully immobilized. The spider then moves in for the death bite. But this is more of a rarity than a rule in the spider world.

Many researchers are studying spider behavior and spider silk in the hopes of some day being able to farm the material or perhaps replicate it through genetic engineering. The silk could be used, for instance, to increase the strength of body armor, or to create skin grafts. "That would be a great thing for the human race," says Coddington.

A handful of companies are currently invested in spider silk, including Ann Arbor, Michigan-based Kraig Biocraft Laboratories, a Swedish biotech firm, Spiber Technologies, and a German company, AMSilk, which says it has genetically engineered a protein that is similar to spider silk that is currently being used in shampoos and other cosmetics.

It's your turn to Ask Smithsonian.

About Alicia Ault

Alicia Ault is a Washington, DC-based journalist whose work has appeared in publications including the New York Times, the Washington Post and Wired. When not chasing down a story from our nation's capital, she takes in the food, music and culture of southwest Louisiana from the peaceful perch of her part-time New Orleans home.

Read more from this author | Follow @aliciaault

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Ask Smithsonian: How Do Spiders Make Their Webs?

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Spiders are skillful engineers, gifted with amazing planning skills and a material that allows them to precisely design rigorous and functional webs. The material-spider silk-has chemical properties that make it lustrous, strong and light. It's stronger than steel and has impressive tensile strength, meaning it can be stretched a lot before it snaps.

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The cause and effect text structure tells why something happened (cause) and what happened (effect).

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Overview:

This article gives information about lions and the way they hunt.

Genre:

Article/Non-Fiction

Grade-Level:

4th

Readability:

Below Grade-Level

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Lions are famous for being the king of the jungle. Their fearsome stature and reputation place them near the top of the food chain. However, Lions have earned their reputation because they are indeed efficient hunters. Have you ever wondered how Lions hunt in the wild?

Lions Vs. Lioness

Just like most social mammals, Lions have roles that they assign in their packs. A pride of Lions typically consists of a group of female Lions - or Lioness - and a few younger cubs that are the descendant of the male Lion. The male Lions have the role of being the protector of the pride, fending off any potential dangers that may threaten the pride.

However, what most people are not familiar with is that Lionesses are in fact, the primary hunters in a Lion pack. Though female Lions may be physically smaller than the male Lions, they make up for it in speed. They are in fact up to 30% faster, reaching top speeds of up to 45mph. Additionally, Lionesses also hunt together in packs, effectively increasing their chances of capturing a prey successfully.

Hunting Methods

In general, there are two known methods that Lions employ to hunt their prey. The first one is by stalking them. You've probably seen this behavior if you have a pet cat, or watched an animal documentary on television. This is the primary way that they hunt, which is to stay hidden for as long as possible while they approach their prey. This is another advantage that the Lioness has over the male, in that their bodies are slimmer, allowing them to stay hidden in the grass longer. Lionesses also work together when they hunt by surrounding their prey as they stay hidden. Eventually, though, the prey will notice or hear the approaching Lion, in which it will become a chase for them both. Once the Lion catches up to the prey, they use their powerful claws to maul at their prey and crush their necks, leaving them paralyzed to be taken back to the Lion's home.

The other way that Lions hunt is a little more straightforward. This is when the male Lion also joins the hunt together with the Lionesses. For the second method, there is no hiding or stalking involved, they go for the big prey and then corner it strategically. Once the prey is cornered, the Lion comes in face to face to fight with the animal. In this scenario, the weight, brute strength and bravery of the Lion is what will determine the outcome of the hunt.

What do you think of the Lion's hunting methods? Did you know about the female Lions being the primary hunters? Learn more interesting facts by visiting the Lions yourself in Bali Safari Park!

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Lions are famous for being the king of the jungle. Their fearsome stature and reputation place them near the top of the food chain. However, Lions have earned their reputation because they are indeed efficient hunters. Have you ever wondered how Lions hunt in the wild? Lions Vs. Lioness...

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The chronology/sequence text structure describes items or events in order, or explains the steps to follow.