Instead of the more common pointed head of many shark species, the hammerhead shark has a wide head, some think it looks like a hammer (hence the name), or a mallet, with its eyes on each end of its head.

The “hammer” shaped head is called a cephalofoil. The wide shape of the cephalofoil provides a wide space for sensory organs called ampullae of Lorenzini; these sensory organs help the shark detect electrical fields which could be signs of prey (e.g., muscle contractions, heart beats, and gill movements).

These highly efficient sensory organs can help the hammerhead shark find one of its favorite foods, the stingray, and can even detect prey that is buried beneath the sand.

Download Shark Fun! Activity Guide for kids and families.

Download Shark Fun! Activity Guide for kids and families.

Kids’ Corner with Ranger Rick®

• Watch: Hammerhead Shark Sing-a-Long
• Watch: Shark Family Reunion with Nina the Nurse Shark
• Watch: Fish Clean a Shark’s Teeth
• Watch: Sharks4Kids
• Play: Shark Kahoot
• Play: Whale Shark Kahoot
• Make: Shark Hat Craft

More Resources About Sharks:

• Quiz: Sharks! The Amazing Creatures That Are Older Than Dinosaurs
• Sharks in the Parks, NWF Blog
• Not So Scary After All: Shark Facts You Might Not Know, NWF Blog
• NWF’s Affiliate Resolution “Protecting Sharks to Safeguard our Oceans”
• Plastic Pollution Impacts on Wildlife, NWF’s Plastics Reduction Partner Program
• Sharks in Atlantic, Gulf, and Caribbean Coastal Waters

They may not have backbones, but their two-chambered hearts will take your breath away (possibly because you need to come up for air). You may have found their teeth on the shore, so now it’s time to dive a little deeper (together, don’t be scared).

Hammerhead Shark 

Love Language: Receiving Gifts  | Personality Type: Conscientious

They say you gotta keep your eyes on the prize, and the hammerhead shark does just that. Fins of the show have asked, “Will anyone’s head turn when the hammerhead enters the villa?” Their eye placement, on each end of their very wide (and long) head, allows them to scan more area faster than any other shark (joke’s on them, because this fish doesn’t even need to turn its head to see you). 

This shark’s name comes from the unusual shape of its head, an amazing piece of anatomy that has been adapted to maximize the fish’s ability to find its favorite meal: stingrays (can’t blame them for nailing down what they really want). They use their wide heads for hunting and can quickly spot prey and pin them to the sea floor, which is vital to their success in feeding.

Hammerheads are widely considered to be highly intelligent due to their unique sensory abilities and complex hunting strategies. They possess a large brain, including a significant cerebellum, and exhibit advanced sensory perception, including exceptional electroreception and vision (they may not read books, but they can certainly read your energy… choose your moves wisely). 

Whale Shark

Love Language: Quality Time | Personality Type: Open-minded

If mysterious is your type, then look no further, whale sharks are unique in that they are covered with hundreds of white spots, and every individual has their own specific spot pattern (like freckles for humans).

In fact, whale shark researchers utilize specialized computer software, originally designed for star mapping, to identify individual whale sharks from photos utilizing their spot patterns (note: this doesn’t help identify their personality traits, so take it with a grain of salt…ocean jokes, amiright?). 

While they are the largest fish in the world, reaching the size of a school bus, they only eat tiny plankton and fish eggs, consumed by filter feeding as they swim slowly with their massive mouths completely wide open. They are one of only three species of filter-feeding sharks in the world (so, if you’re looking for a conscious eater who chooses to snack all day rather than eat big meals, then you have found your match). 

Great White Shark

Love Language: Physical Touch | Personality Type: Neurotic

Before you get the ick, understand the great white shark is more than meets the eye. They are born at the top of the food chain, growing up to 20 feet long, but to make it to adulthood, the pup must avoid other predators, while at its most vulnerable, including other great white sharks (did someone say trauma bond?). 

If you like surprises, then you may have met your match. They utilize the element of surprise as they hunt, their electromagnetic sense to sense heart activity, and their strong sense of smell to find their prey in the ocean. These sharks don’t chew their food—they rip off chunks of meat, swallow them whole, and can then last almost two months without another big meal (so if you’re into sharp jawlines, then look no further). 

Nurse Shark

Love Language: Acts of Service | Personality Type: Agreeable

If you consider yourself calm and nurturing, then the slow-moving bottom-dwelling nurse shark may be your type. An introverted delight, they are found in the warmer, shallower waters of the ocean, typically in the western Atlantic and eastern Pacific Oceans. They can reach up to 14 feet and have extremely powerful jaws filled with thousands of tiny, serrated teeth (so if you’re looking for a killer smile, the ocean floor is yours). 

They use their strong jaws to break down shellfish and sometimes coral, but prefer to regularly eat fish, shrimp, and squid (a pescatarian’s dream, if you will). They have distinctive tail fins that can be up to one-fourth of their total body length (this doesn’t mean they are smol, their tails are quite long and strong).

Unlike most sharks, they are very smooth to the touch (some would say their skincare routine is unmatched). Although abundant in numbers, due to their habit of being closer to shores, human activity is putting pressure on the species (introverts need space to live life swimmingly). 

Bull Shark 

Love Language: Words of Affirmation | Personality Type: Extraverted

“I’ve got a text!”…. That’s Bull shark. Don’t be salty, but all sharks must keep salt in their bodies to survive, and most can only live in saltwater oceans. However, bull sharks have developed special adaptations through their kidney function and special glands near their tails that help them keep salt in their bodies even when they’re swimming in freshwater (if they wanted to, they would).

Bull sharks have a (strangely) diverse diet, including dolphins, sea turtles, and even other sharks (it’s giving ‘growing up in a household where you finish your plate’). They live throughout the world, in shallow, warm ocean waters and have been known to even swim into freshwater rivers, especially those with brackish, semi-saline qualities (if you’re looking for a well-traveled partner, then you are in the right place). 

Want to learn more about sharks? Check out some of our other fincredible blogs! 

• Shark Week: Five Fin-credible Facts 
• Test Your Shark Skills 
• Not So Scary After All: Shark Facts You Might Not Know
• Sharks in the Parks
• Sharks & Plastic Free July

Blue Sharks

Unfortunately, these sharks are highly impacted by plastic pollution. It is very common for these sharks to get tangled in fishing gear. In some cases, the plastic can cover their gills, preventing them from getting oxygen.

Getting tangled can prevent these animals from growing correctly, leading to malformations or death. It can also prevent the sharks from being able to swim. They also ingest plastic litter, which causes their stomachs to become full. This prevents them from getting the food and nutrients they truly need, ending in starvation and death.

Whale Shark

Whale sharks hunt for food in inshore waters, where tons of plastic tend to accumulate. In some regions of the world, whale sharks may consume as much as 137 pieces of plastic per hour. These microplastics can release toxins that accumulate over time and potentially alter hormones regulating the animal’s metabolism, reproductive functions, and growth and development.

For a number of marine species, the larger pieces of plastic can cause internal damage to organs and block passageways to the stomach, which can lead to starvation and death.

Tiger Shark

The tiger shark may be known for its cool name, however, it’s not cool to wear plastic, and more tiger sharks are being found entangled in plastic waste. In a recent study of 66 tiger sharks, one of the sharks was found dead, entangled in plastic straps. The strap had engulfed the shark’s fin, preventing it from swimming normally.

Another shark, found alive, had severe malformations suggesting that the strap had become attached to the shark at a much younger age. In both situations, the sharks had visible wounds from the straps, which could also put these animals at risk of disease and infection.

Many, if not all, species of sharks face the risks associated with plastic pollution. Here are a few things you can do to show your support for our finned friends.

• Support legislation for a global plastics treaty
• Conduct a plastic audit and reduce your plastic consumption
• Reuse items as many times as possible before discarding them
• Repair items where possible before sending them to the landfill
• Join your local buy-nothing group and swap items for free

Quick Facts About Sharks

• There are more than 530 species of sharks in the world
• More than 50 shark species can be found in the waters along the east coast of the U.S.
• The largest shark is the whale shark, it can be as long as 60 feet
• The smallest shark is the dwarf lantern shark, that can fit in the palm of your hand

Sharks are critical apex predators contributing to a balanced marine ecosystem. Seagrass beds provide important habitat for many fish and invertebrate species as they mature, before moving onto coral reefs and other ecosystems. Coral reefs, kelp forests, and seagrass beds are reliant on sharks’ existence in the food chain to keep these beautiful and important habitats stable.

The National Wildlife Federation (NWF) is committed to wildlife conservation and education, and as part of our work, we spotlight vulnerable wildlife species needing extra support to ensure their populations thrive in an ever-changing world. The International Union for the Conservation of Nature (IUCN) Red List, which has identified that more than 47,000 wildlife species worldwide are threatened with extinction, including 37 percent of sharks and rays.

An endangered species is a plant or animal facing extinction if its population numbers do not increase. In the U.S., individual states and the federal government can list a species as threatened, endangered, or a number of other designations. The U.S. Endangered Species Act (ESA) protections are enforced at the federal level by the U.S. Fish and Wildlife Service (USFWS) and the National Marine Fisheries Service (NMFS) for certain marine species. The IUCN Red List provides conservation status assessments for species globally used by governments internationally to determine protections.

Continue reading to learn more about sharks before you begin the quiz or scroll down to get started!

Here are a few species of sharks that can be found in the oceans along the U.S. coasts that are protected under the U.S. Endangered Species Act:

• Common angel shark (endangered)
• Daggernose shark (endangered)
• Ocean whitetip shark (threatened)
• Scalloped hammerhead shark (endangered)
• Striped smoothhound shark (endangered)

Just for Kids

• Read Ranger Rick article on Great hammerhead sharks
• Watch Shark Science for Elementary, Middle and High School by Sharks4Kids

Listen to the Hammerhead Shark sing-a-long!

Here are a few species of sharks identified as vulnerable or endangered by the IUCN:

• Bonnethead shark (endangered)
• Great hammerhead shark (critically endangered)
• Great white shark (vulnerable)
• Greenland shark (vulnerable)
• Sand tiger shark (critically endangered)
• Whale shark (endangered)

Test your knowledge about sharks and learn some cool facts!

The National Aquarium in Baltimore

If you are in the neighborhood, visit The National Aquarium in Baltimore, Maryland.

The National Aquarium, NWF’s Maryland affiliate partner, connects people with nature to inspire compassion and care for our ocean planet. They house 10 shark species including the sand tiger and sandbar sharks.

One of their most popular exhibits is Shark Alley, however only six of the 10 shark species can easily be found, which makes the other four a fun challenge!

The Aquarium also has their Blacktip Reef exhibit that hosts daily educational opportunities for visitors to learn more about sharks including the behind-the-scenes shark tours, and “shark talks.”

Read more about The Aquarium’s sharks, Hidden Gems: Shifty Sharks.

Take action to protect sharks

• Celebrate Shark Awareness Day on July 14 by educating your family and friends about sharks and their important role in the marine ecosystem. Right during peak beach season and before the well-known Shark Week, share with others these wonders of the depths.
• Adopt a storm drain. Adopting a storm drain is a simple and fun way you can remind others to keep trash and chemicals that harm wildlife out of our local waterways and oceans.
• Restore seagrass beds. Volunteer with a local organization to protect and restore the sea grass beds.
• Find out what your plastic eco-score is and adopt a new habit to reduce plastic waste.
• Purchase coral reef-safe sunscreen; these sunscreens are mineral-based.
• Symbolically adopt a great white shark and support conservation efforts to protect the great white sharks and other wildlife.
• Advocate for laws that protect endangered shark species and other wildlife including the Endangered Species Act, the Marine Mammal Protect Act, and the Recovering America’s Wildlife Act.

Resources for Kids, Teachers, and Parents

• Great Hammerhead Sharks. This shark isn’t just supersized and super cool. It has superpowers, too!
• Is That a Shark? Sharks come in all shapes and sizes. And not all of them have razor-sharp teeth
• A Whale of a Shark. Meet the whale shark – the biggest fish in the world
• Make a shark hat (craft)
• Swimming with… Sharks. No, these kids aren’t in any danger. They’re discovering how cool sharks can be. Wade in and see for yourself!
• Dive Into Shark Education from the Classroom
• Shark Education with Sharks4Kids (Content for Elementary, Middle and High Schools)

More Resources About Sharks:

• Sharks in the Parks, National Wildlife Federation Blog
• Not So Scary After All: Shark Facts You Might Not Know, National Wildlife Federation Blog
• NWF’s Affiliate Resolution “Protecting Sharks to Safeguard our Oceans”
• Plastic Pollution Impacts on Wildlife, NWF’s Plastics Reduction Partner Program
• Sharks in Atlantic, Gulf, and Caribbean Coastal Waters

For Endangered Species Day 2026, NWF is spotlighting the hellbender. Hellbenders are fully aquatic amphibians, meaning they spend all of their lives in water. They primarily feed on crayfish, snails, small fish, tadpoles, insects, and worms and have long life spans, sometimes up to 30 years.

Hellbenders “breathe” through their skin even though they have gills, but like most amphibians, lose their frilly external gills once they reach adulthood. Their wrinkly skin allows them lots of surface area to breathe while underwater. That distinctive, rippled appearance has earned them one of their many nicknames, “lasagna lizard”. There are two subspecies, and unfortunately, both are facing serious conservation challenges. They are the eastern hellbender and the ozark hellbender.  

Read our blog, What in the Hellbender?, and take our quiz to learn more about the largest salamander in the Americas.

Continue reading or scroll down to our “Take Action” section to learn how you can take action on May 15 (or anytime)!

What is an Endangered Species?

An endangered species is a plant or animal facing extinction if its population numbers do not increase. In the U.S., individual states and the federal government can list a species as threatened, endangered, or a number of other designations. The U.S. Endangered Species Act (ESA) protections are enforced at the federal level by the U.S. Fish and Wildlife Service (USFWS) and the National Marine Fisheries Service (NMFS) for certain marine species.

U.S. states enforce protections for species listed at the state level. The International Union for Conservation of Nature’s (IUCN) Red List provides conservation status assessments for species globally that are used by governments internationally to determine protections.

Endangered Species in the U.S.

Currently, there are over 1,300 endangered or threatened species in the U.S.

Some of the endangered wildlife in the U.S. include:

*This list does not reflect any prioritization of endangered species; it’s an attempt to show the diversity of species, both plants and animals, endangered in the U.S.

• Arizona hedgehog cactus
• Blue whale
• Cooley’s water-willow
• Georgia blind salamander
• Giant sequoia
• Karner blue butterfly
• Loggerhead sea turtle
• Ocelot
• Northern long-eared bat
• Red wolf
• Scalloped hammerhead shark
• Sandhill crane
• Sea otter

Get ready to color! Download NWF’s endangered species coloring book.

Celebrating Success of the U.S. Endangered Species Act

In 2023, the Endangered Species Act celebrated its 50th anniversary. “The ESA has saved hundreds of animals that once teetered on the brink of extinction. Without its protections, we might not have gray whales spouting off our coasts today or alligators roaming mangrove swamps, brown pelicans gliding above beaches or grizzly bears lumbering through western mountains.”

One of the most successful ESA stories is about the gray wolf. After the gray wolf was listed as endangered in 1974, the USFWS, the National Park Service and other agencies got together and began to plan a reintroduction into the Northern Rockies region, specifically Yellowstone National Park (Wyoming and Montana) where the wolves had been missing since 1926.

During the timeframe 1994 to 1996, the USFWS and Canadian wildlife biologists captured 41 wolves in Canada and released them in both Yellowstone National Park and central Idaho. By 2008, USFWS biologists estimated that 1,639 wolves roamed through Montana, Wyoming and Idaho—five times higher than the minimum population goal in the species’ recovery plan. With the return of gray wolves the Yellowstone ecosystem is more historically complete and resilient.

Read about more ESA success stories: The Endangered Species Act at 50 & What’s Next for Wildlife and 12 Wildlife Success Stories.

Education and Action through NWF and LG Electronics’ Vulnerable and Endangered Species Campaign

At the heart of NWF’s mission is to educate and encourage action for wildlife, specifically threatened and endangered species. The Red Wolf, the most endangered wolf in the world, was a featured animal as part of LG Electronics’ vulnerable and threatened species campaign. In coordination with NWF’s state affiliate, the North Carolina Wildlife Federation, NWF supports Red Wolf recovery efforts in the Albemarle Peninsula of North Carolina. Watch the Red Wolf 3D video on LG’s Times Square billboard in New York City and test your knowledge of the most endangered wolf in the world.

Read NWF blog: Students Tell us Why Protecting Endangered Species is Important!

The grizzly bear was spotlighted last fall as part of the Life’s Good campaign. The grizzly bear is a subspecies of the brown bear and is listed as threatened, in the lower 48 states, under the ESA. Historically, grizzly bears were thriving with an estimated 50,000 in the contiguous U.S. Unfortunately, by 1975, their numbers had dropped to fewer than 1,000 and they were facing extinction due to hunting and other threats; this tremendous population decrease prompted the ESA listing.

Watch the grizzly bear 3D video on LG’s Times Square billboard in New York City and test your knowledge on the grizzly bear and other North American bears.

Ranger Rick® Sparks Passion for Endangered Species and Other Wildlife Among Kids

NWF believes that when we share our love of wildlife with kids, we can inspire a lifelong passion to learn about, explore, and protect our natural world. Ranger Rick®, NWF’s friendly raccoon character, helps children of all ages discover and connect with nature so that they, too, become good stewards of the environment and protect endangered species and other wildlife. Ranger Rick® magazine spotlights endangered species to help educate youth about these vulnerable plants and animals, and features fun crafts, recipes, jokes, and more to make learning fun.

Check out a few of our endangered species online resources:

• Floating with Sea Otters,
• Gray Wolves
• Path for Panthers
• Sea Turtle Cookies (recipe)
• Pine Cone Snowy Owl Pals (craft)
• 5 ways You Can Help Endangered Species
• 50 Ways to Love the Earth!

Learn more and subscribe. Looking for more ways to introduce kids to the world’s most vulnerable plants and animals? Check out these book recommendations on endangered species from NWF’s Ranger Rick® team.

Take Action: Endangered Species Cannot Recover Without the Help of Humans

Take action for Endangered Species Day, choose one or more of the following actions to support wildlife:

• Get Ready to Color with NWF’s Endangered Species Coloring Book. Download our coloring book and learn fun facts about some of the most vulnerable wildlife.   
• Wildlife Mascots. Turn your school’s wildlife mascot into a tool for student-led environmental learning and action.
• Be a Voice for Wildlife. No matter how big or small we think we are, when we speak up together, our voices can have a huge impact! It can be as simple as talking to friends and family, writing letters, and sharing your voice on social media. 
• Plant Native Milkweed to support the Monarch butterfly and other pollinators. Visit your local nursery or you can shop for milkweed through NWF’s Garden for Wildlife, the native plant collections are specially curated by region.
• Build a Bat Box to support the Northern long-eared bat and other bat species. Access more tips, tools and videos to turn outdoor space into a beautiful spot that supports wildlife. Watch a how-to video to build a bat box, created by Roanoke College students.
• Find out what your plastic eco-score is and adopt a new habit to reduce plastic waste and help keep plastic out of the streams, rivers, and oceans. Learn about wildlife impacts from plastic pollution.
• Get Creative! Enter the Endangered Species Day Chalk Art Contest. Get outdoors and create a chalk art masterpiece to spotlight a threatened or endangered species and enter to win a prize.

Interested in Learning More?

• Watch The Americas to learn about endangered species and other wildlife in North and South America; all episodes are streaming on Peacock. Find watch kits for each episode of The Americas and enjoy fun classroom activities, amazing animal facts, and discover ways to help protect wildlife and wild places.
• NWF’s online wildlife guide
• NWF’s wildlife conservation efforts
• NWF efforts to connect Kids and nature
• NWF’s bison restoration campaign
• NWF efforts to protect manatees
• Learn how NWF is saving the greater sage-grouse
• Learn how NWF is reversing mule deer declines
• Learn about the Recovering America’s Wildlife Act
• Learn about your state’s wildlife action plan
• Symbolically adopt a wildlife species

The National Wildlife Federation K-12 education team is joining Jillian Morris, a marine biologist and founder of Sharks4Kids, to host a virtual sharks webinar series. First, explore the biology, behavior, and critical role of sharks in ocean ecosystems.

Next, learn about shark conservation and cutting-edge research, including how scientists tag and track sharks to study their movements and behavior. Explore the technology behind shark tagging, see actual research in action, and discover how this science helps protect these incredible animals.

These webinars are ideal for classrooms, homeschools, and young ocean enthusiasts to explore the remarkable qualities of sharks.

Register today for the upcoming live shark science webinar!

• 4/29 Middle and High School
• 4/30 Elementary School

The first webinar in the two-part series, recorded in February, is now available on the EcoSchools YouTube channel and features tailored content for elementary, middle, and high school students.

Check out Sharks4Kids Free Resources

Elementary School

• Toilet Roll Hammerhead
• Grade 3-4 Shark Adaptations
• See all other shark activities for grades K-5 here.

Middle School

• Middle School Dive into the World of Sharks Unit
• BRUV (Bated Remote Underwater Video Systems) Shark Science
  

High School

• Climate Change and Shark Behavior
• Journal Article Activity: Biological responses of sharks to ocean acidification

Sharks4Kids

Sharks4Kids is dedicated to creating the next generation of shark advocates through education, outreach, and adventure. They provide free educational resources, virtual lessons, in-person school visits, and hands-on experiences to inspire curiosity and conservation. Bringing the world of sharks into classrooms and communities empowers kids to become ocean stewards and protect these incredible animals.

About the Presenters

Jillian Morris

Jillian Morris is a marine biologist, educator, photographer, mom, and the founder of Sharks4Kids, a nonprofit dedicated to inspiring the next generation of shark advocates. She has spent thousands of hours diving with sharks worldwide, using her experience to promote conservation through education and storytelling. Jillian’s work has been featured by National Geographic, BBC, and Animal Planet, and she is passionate about making shark science accessible to kids everywhere. Through Sharks4Kids, she continues to empower young minds to understand and protect these incredible animals.

Michelle Trigg

As a scuba Instructor, Michelle has spent years teaching people how to dive and encountering different shark species around the globe. You will find her visiting classrooms, teaching virtual lessons, or creating shark craft projects for kids. She believes that the next generation can play a critical role in protecting sharks and our wider oceans through curiosity and creativity.

Sara Casatero

Sara Casareto is a marine biologist, public speaker, science communicator, and Sharks4Kids ambassador, passionate about marine science and conservation. Sara is currently a PhD candidate at Florida International University studying shark behavior and biology. Sara has been diving with sharks for over 15 years and, in addition to studying sharks, is just as excited about sharing her shark knowledge with students of all ages. Her work has been featured on National Geographic and local news channels.

Jeynaliz Ortiz Gonzalez

Jeynaliz is a Master’s of Professional Science, Marine Conservation student at the University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Science. She is also a newly onboarded intern in the Shark Research and Conservation Program (SRC), also known as the MacDonald Lab. Her research focuses on local fisherman communities and shark consumption. 

Great White Shark 

When a great white shark is born, it immediately swims away from its mother. This isn’t rare for many sharks, as they grow very early. At birth a baby great white shark is about five feet (1.5 meters) long; as it grows it can reach a length up to four times that (20 feet). They are born near the top of the food chain, but to make it to adulthood, the pup must avoid other predators—including other great white sharks.

They utilize the element of surprise as they hunt, their electromagnetic sense to sense heart activity, and their strong sense of smell to find their prey in the ocean. These sharks don’t chew their food—they rip off chunks of meat, swallow them whole, and can then last almost two months without another big meal (new shark diet coming soon).

Whale Shark

The largest fish in the world is the graceful whale shark. Though they reach the size of a school bus (no, seriously), whale sharks eat tiny plankton and fish eggs, which they consume by filter feeding as they swim slowly with their massive mouths completely wide open. They are one of only three species of filter-feeding sharks in the world. 

Whale sharks are unique in that they are covered with hundreds of white spots, and every individual has their own specific spot pattern (like freckles for humans). In fact, whale shark researchers utilize specialized computer software, originally designed for star mapping, to identify individual whale sharks from photos utilizing their spot patterns.

Hammerhead Shark

The hammerhead’s eye placement, on each end of its very wide (and long) head, allows it to scan more area even quicker than any other shark. The hammerhead shark also has more electromagnetic sensors across its head than other species, which helps it detect and triangulate prey extremely well in the ocean. 

This shark’s name comes from the unusual shape of its head, an amazing piece of anatomy that has been adapted to maximize the fish’s ability to find its favorite meal: stingrays (maybe their nickname can become nails..). Hammerhead sharks use their wide heads for hunting and can quickly spot prey and pin them to the sea floor, which is vital to their success in feeding.

Nurse Shark

Nurse sharks are slow-moving bottom-dwellers and are generally harmless to humans. They are found in warmer, shallow waters in the ocean, typically in the western Atlantic and eastern Pacific oceans. Although they stay in shallower waters, they can be huge—up to 14 feet—and have extremely powerful jaws filled with thousands of tiny, serrated teeth. 

They use their strong jaws to break down shellfish and sometimes coral but prefer to regularly eat fish, shrimp, and squid. They are gray-brown and have distinctive tail fins that can be up to one-fourth of their total body length. Unlike most sharks, nurses are very smooth to the touch (disclaimer: don’t try this at home). Although abundant in numbers, due to their habit of being closer to shores, human activity is putting pressure on the species.

Bull Shark

Bull sharks have a diverse diet, including dolphins, sea turtles, and even other sharks (carnivorous, but diverse for a shark, ok?). They live throughout the world, in shallow, warm ocean waters and have been known to even swim into freshwater rivers, especially those with brackish, semi-salted qualities. 

All sharks must keep salt in their bodies to survive, and most can only live in saltwater oceans. However, bull sharks have developed special adaptations—through their kidney function and special glands near their tails—that help them keep salt in their bodies even when they’re swimming in freshwater (imagine having an internal hydration tank when working out).

Want to learn more about sharks? Check out some of our other fincredible blogs! 

• Test Your Shark Skills 
• Not So Scary After All: Shark Facts You Might Not Know
• Sharks in the Parks

While Jaws cemented the great white as the most well known shark species, there are hundreds of shark species in a mindblowing diversity of sizes, shapes and behaviors, and most of what you think you know about sharks isn’t quite true. Sharks–including white sharks–don’t actively hunt humans, but we humans are decimating shark populations across the planet. Sharks are cool, and they need our help now more than ever. Read on to discover just how cool, and how you can help. 

Greater than Great Whites

Shark-fueled disaster movies like Jaws and Sharknado have popularized the great white shark as the king of the seas, but the white shark is just one of more than 400 species of shark in the world’s oceans – and counting! 

New species are still being discovered and described by science, like the recent discovery of the American pocket shark in the Gulf of Mexico. The tiny new species wasn’t named for its pocketable size, but rather for the pockets on either side of its body that excrete a glowing liquid to attract its prey.

If that photo doesn’t look like what you’d typically imagine a “shark” to look like, then the next photos may be even more surprising.

Sharks are elasmobranchs, a taxonomic group that also includes skates and rays. The visual similarities between sharks and their flatter cousins becomes apparent in species like the wobbegong shark:

…or the Argentine Angelshark:

Some sharks, like the sawshark, look less like rays and more like swordfish: 

They also vary greatly in size. While the sawshark grows to only around 5ft in length, the basking shark can grow up to 30 feet in length – that’s as long as a school bus! And the whale shark, the largest fish in the sea, can be even larger – up to 40 feet long:

Sharks have a lot of unique adaptations. One defining feature is their skeleton, which is made up of cartilage rather than bone. Another is their teeth; sharks shed and grow new ones throughout their lifetimes. Unlike bony fish, they don’t have swim bladders for buoyancy, which allows sharks to move up and down through different depths in the water column without worrying about changes in pressure.

The positioning of their pectoral fins, which cannot bend upward like those of bony fish, means that sharks can only swim forwards. Many (but not all) shark species have to keep moving in order to keep water flowing over their gills so they can breathe.

Sharks reproduce via internal fertilization just like mammals, unlike most fish which eject eggs and sperm into the water for external fertilization. Some sharks lay eggs while others give birth to live pups!

Test your knowledge – take our shark facts quiz!

Take the quiz!

Fish are Friends! Including Sharks!

While sharks have been demonized in pop culture due to their size, scary-looking teeth, and natural predatory behavior, deadly human-shark interactions disproportionately happen in fiction compared to their frequency in real life.

Sharks generally avoid humans and only interact out of curiosity, in defense when we threaten them or invade their territory, or if they confuse humans for their normal prey, which varies from fish to marine mammals to seabirds, depending on the species. But no matter the reason, shark interactions with humans are extremely rare occurrences.

Shark bite fatalities, while terrifying fuel for the imagination, only occur about six times per year. That’s in comparison to the 100 million sharks that are killed by humans every year! 

As predators, sharks are critically important to maintaining healthy marine ecosystems. Predators keep populations of prey species strong by feeding on the weak and the sick, and they keep prey populations in check which maintains a healthy balance. Many sharks are important prey for other wildlife from marine mammals, seabirds, and other fish (including other sharks). Healthy oceans directly benefit humans.

Sadly, many species of shark in American waters are endangered or threatened due to human activities. Overfishing threatens shark populations both by directly catching sharks and by depleting their food sources. Shark fin harvesting is one particular threat to shark populations worldwide – it’s estimated 73 million sharks are killed globally each year for their fins. And as climate change and ocean acidification from human activities threaten coral populations throughout the world’s oceans, tropical sharks may lose critical food sources. The simple, misinformed fear that helps the senseless killing of sharks and indifference to shark declines is a major threat to these important animals.

Many shark conservation efforts are underway in the U.S., as coastal states have developed wildlife action plans listing many sharks as species of greatest concern. The basking shark, whale shark, great white shark, and many others are high priority species for coastal states.

TAKE ACTION: Support critical species recovery and resilience by urging your representative to co-sponsor the Recovering America’s Wildlife Act!

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Still can’t shake your fear of sharks? If you are headed to the beach and worried about potentially interacting with marine life – although you’re much more likely to be harmed in a car accident driving to the beach than by a shark when you go swimming – you can minimize the tiny, tiny risk from sharks by keeping out of the water if you have a cut or are bleeding, and by not going swimming alone or at dawn, dusk or nighttime when many shark species are active. (No, dolphins are not going to protect you from sharks–in fact, seeing dolphins could mean that sharks could be nearby as these two predators often hunt the same prey.)

So this week, whether you’re a shark buff or a SharkFest follower, enjoy learning about some of the ocean’s most fascinating creatures! Just remember: sharks are important ocean creatures, not human-hunting monsters – and they need our help!

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Want to learn more facts about these amazing animals? Read more about sharks in our blog.

In Hawai‘i, sharks hold a special place in cultural practices and are also vitally important to Hawaii’s unique marine ecosystem. Sharks are one of the most prevalent organisms identified as ‘aumakua, or ancestral family deities in Hawai‘i, and to honor this an ancient kapu or taboo was placed to protect most sharks from being fished or killed. Their cultural importance is emphasized further by the existence of kahu manō, or shark keepers, who held the responsibility of caring for patron sharks and in turn brought protection and bountiful resources. Today, many cultural practices have been oppressed and lost and there are no state-wide laws protecting sharks anymore.

One Hawaiian Family has sought to revitalize the practice of caring for sharks and restore the protection they once enjoyed. The Nakachi family continues the traditions of their ancestors by studying and caring for sharks in West Hawaii. They are also a part of the Kaupulehu community that has spent decades fighting to conserve their local resources. The Kaupulehu Marine Life Advisory Committee (KMLAC) was formed in 1995 and in 2016 successfully passed legislation to create a 10-year no-take-zone along a 3-mile stretch of coast. Sharks are one of several elements of KMLAC’s conservation action plan that are being studied. The KMLAC seeks to form adaptive management strategies to cooperatively manage marine life with state agencies. This includes supporting additional legislation to further protect sharks, particularly since they are such wide-ranging beings. The Conservation Council for Hawai‘i (CCH) has supported this effort by standing with Native Hawaiians in litigation efforts such as a lawsuit filed this year by CCH, the Nakachi Family, and Earth Justice that led to further protections being required for the Oceanic Whitetip shark.

CCH proudly supports the work that indigenous cultures do here in Hawai‘i and around the world. We are grateful for the work of the Nakachi Family and will continue to support their efforts to cooperatively manage marine life with state agencies by providing testimony in support of state legislation attempting to protect sharks from purposefully being harassed or killed, sharing their stories with, and mobilizing the support of our members and partners.

Keep up to date with Conservation Council for Hawai‘i’s work for wildlife by following them on Facebook.

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