Shark Conservation

Today we discussed conservation of sharks. Millions of sharks are killed each year by humans. Some are caught by sport fisherman, some are harvested for oils, meats, and other things; many of them are being harvested for their fins. Finning wastes 95% of an animal, and the sharks are often tossed back in the ocean alive after being finned to die a slow painful death. For more information, click here.

The fins are harvested for shark fin soup. Shark fin soup is considered a delicacy in some countries and can sell for upwards of a hundred dollars a bowl.

The next thing we talked about was shark attacks. Most shark attacks are actually provoked by humans. Other shark attacks like bump-and-bites and hit-and-runs are the shark investigating a human to see if it is something good to eat. Once the shark tries it, it finds it doesn't like humans, it will swim away. Unfortunately for us humans, we are not so tough and kind of squishy and shark attacks damage us.

Skates and Rays

Today in class we talked about skates and rays. Skates and rays are depressed relatives of sharks that often spend most of their time on the benthos. (There are a few exceptions like manta rays pictured in the upper right)

Skates and rays are really similar and often hard to tell apart. Some rays look like flat sharks and some flat sharks look like rays, so we are going to be general in identifying skates and rays. In general, skates have fins on the tips of their tails.

Only rays can have stingers, and not all of them do. They can have 1 to 3 stingers from 5 to 15 inches long. See the picture below.

I often get asked about Steve Irwin, the famous Crocodile Hunter when we talk about stingrays. Yes, Steve Irwin was killed by a stingray, but his type of accident was very rare. Steve got stabbed in the heart which injected venom right into an important organ. Also, he removed the barb which caused just as much damage going in as it did coming out because of the sharp serrated edge. For more information about Steve Irwin's death check here and here.

Still worried about shark attacks? Check the newest stats here at the Florida site.

Shark Senses

Today we learned about shark senses. Sharks have a large brain to help process the sensory overload they must get from the SEVEN senses they have. They have the five we have plus a lateral line (pressure and vibrations) and the ampullae of lorenzini (electro-reception).

Follow this link for a cool interactive about how shark jaws stick out when they attack their prey! The interactive is down at the bottom.

If you are doing a final project on a shark... check out this new link! www.shark.ch

And once again... one try only... how much do you know about sharks? MsJ scored a 1467. Try Shark Weeks Ultimate Shark Challenge to see how much you know. Please limit yourself to 15 minutes.

Shark Reproduction

Today students learned an introduction to sharks. We talked about the history of sharks, common characteristics of cartilaginous fish and then the reproductive strategies of sharks.

Not a lot is known about shark reproduction because in many cases it has never been observed.

Some sharks are oviparous and lay eggs (pictured). These egg cases are known as mermaid's purses. You can see the baby shark and its nutrient-rich yolk through the leathery egg case.

Some sharks are viviparous and have live birth a lot like mammals.

And some sharks are ovoviviparous and keep their eggs inside the uterus before releasing them... so its making eggs and then kind of having live birth.

Fishing Methods and Sustainable Harvesting

We discussed fishing and seafood harvesting, the good, the bad, and the just plain ugly.

The truth is that our oceans are being fished to extinction and emptiness. We are harvesting more and more fish from smaller and smaller populations. What is a person to do that wants to eat seafood, but not hurt the environment?

BECOME AWARE. Most people do not know where their seafood came from or how it was caught.

How it was caught makes a big difference. Different fishing methods have pros and cons for the environment and regarding bycatch (fish and other organisms like sharks, sea turtles, sea birds, and dolphins, that are caught, often killed, and not really wanted).

One of the biggest things to avoid is any kind of imported shrimp. Imported shrimp are either caught with destructive trawl nets that destroy habitats and that do not have TEDs that allow turtles and dolphins to escape unharmed or they are farmed in aquaculture plants that are built on destroyed mangrove forests that then leach pollution and kill nearby coral reefs.

The United States requires all shrimp trawlers to be outfitted with TEDs and regulates where they can trawl. The US has higher standards for pollution laws and laws protecting shore habitats that result in less damage to the environment. Choose US shrimp ONLY!

If you would like more information - check out SeafoodWatch, a non-profit organization that independently evaluates fisheries for their sustainability and environmental impacts.

This article also has some really nice information and photos. Sustainable seafood.

ByCatch

Netting is the most popular method of commercial fishing because a lot of fish can be caught in short amount of time without a lot of effort.

One the major problems with most commerical fisheries is the amount of bycatch. Bycatch is anything caught in the net that you do not want. This could include edible fish that your company is just not equipped to process.

Most organisms brought up in nets as bycatch do not survive because they are crushed or drowned. Sea turtles and dolphins sometimes get swept into nets and drown because they cannot make it to the surface to breathe.

Most scientists and fisherman agree that the oceans have been and are being overharvested. People may not like regulations, but without regulations, many fish species that we used to commonly consume would be extinct.

Fish Tails & Fish Reproduction.

Fish tails (caudal fin) indicate how fast and how much a fish swims. For this class, we are focusing on the crescent (not pictured), forked (e), square (d), rounded (b), and funky (c, f, h). As you can see there are more fish tail shapes out there.

Crescent caudal fins indicate a very fast fish that is constantly swimming - not time for resting, it is time to go go go! Forked caudal fins are the second fastest, and very maneuverable. Square fins are for your every day swimming fish - they have ok acceleration ad maneuvering. Round fins and Funky fins are slooooooow swimmers that don't spend a lot of time swimming. They can be quick for very short bursts.

Fish reproduce in a variety of ways. Most are broadcast spawners, meaning that when the time is right, the females release their eggs, the males release their sperm and they both meet and mix producing fertilized eggs that develop into fish fry (meroplankton) and eventually into adult fish. These snapper are spawning and you can tell by the large cloud of gametes in the water.

By producing a lot of eggs, the snapper hope to overwhelm any predators trying to make a meal so that there is no way all the fry are eaten and some will have a chance of surviving. Course there are predators that time their arrival with this spawning to eat all those nutritious eggs and gametes.... Yum!

Fish Shapes

Today in class we discussed fish mouth shape and body shape and what they mean about the fish.

Many fishes are identified by looking at or into the mouth. The number of mouth-types exhibited by different species is nothing short of astonishing. Three lakes in Africa contained about 900 species of cichlids, nearly all differentiated mainly by the way their mouths are shaped. (This number is rapidly dwindling, by the way, as the cichlids in these lakes are driven to extinction). Cichlid mouths are variously adapted to eat other cichlids' eggs, scales pulled from fishes' living bodies, algae from rocks, tiny invertebrates, and many other forms of food. The arrowana of South America has a mouth adapted for spitting water with precision at insects perched on overhead branches. Parrotfish mouths have evolved to look and act like beaks, which they use to grind at coral, making the sand that surrounds coral reefs. Seahorses and pipefish have tubular mouths for sucking in small prey in narrow places like a vacuum cleaner.  SOURCE

Fish with forward facing mouths eat what is in front of them - no surprise. Downward mouths eat algae, prey below them like crustaceans and molluscs, or they take in mouth fulls of gravel, eat the particles, and spit the gravel back out. Upward facing mouths indicate the fish eats prey above them - typical of benthic ambush predators. There are also bills and beaks. Bills are long and skinny used for poking in crevices and eating plankton one at a time. Beaks are used for chomping and can be seen on the parrotfish, a fish that chomps on the algae growing on the surface of dead coral. Fish can also have very large mouths common on filter feeders and fish that swallow large prey whole. Fish also have teeth - a surprise to many - and come in many shapes and size.

Body shape also tells you a bit about a fish. Com- pressed fish have flash and look skinny and can only be found in slow moving waters like coral reefs. Fusi-form fish are tapered like footballs and are very streamlined for constant fast swimming. Depressed fish are benthic and squashed looking. Eel shaped fish are poor swimmers and live on the benthos or in cracks and crevices.

Here is a website you can use to identify shapes - realize they are named a bit differently than how I do in class.

Jawless Fish

Today we discusses jawless fish. Jawless fish are primitive fish with a notochord instead of a backbone and a flat rasping mouth that cannot close like ours. As a result thes fish cannot bite... only scrape and hold on.

Pictured to the right, you can see five lamprey mouths and one lamprey head with blue eyes and seven gill holes.

Jawless fish include lampreys which are parasites and hagfish which are detritavores. Neither one will ever win a beauty contest.

Echinoderms

Echinoderm means spiny skin. Echinoderms include sea urchins, sea stars, sand dollars, sea cucumbers and some other odd organisms like feather stars and basket stars. All echinoderms have radial symmetry, spiny skin, and an endoskeleton called a test.

Most people are familiar with an orange sea star because on the east coast, that's all we've got. On the west coast and in other places around the world, it is easier to find a variety of sea stars in other colors and with different amounts of legs.

Sea stars have powerful tube feet that use water suction to open molluscs. When they eat molluscs, they actually stick their stomach into the shells of the mollusc, digest it, and then put their stomach.



Feather stars and basket stars both have crazy looking legs that they wave around to filter feed. Sea urchins and sand dollars are both covered with protective spines and eat with a scraping mouth called Aristotle's Lantern.

Sea cucumbers have lost most of their exoskeleton and are a bit squishier than other echinoderms. Sea cucumbers are important detritus eaters on the sea floor. When attacked by predators they will expel their guts as a meal for the predator as they make a get away. Sea cucumbers are able to regenerate these guts over time.

Crustacean Basics - A Review for Marine Ecology Class

Crustaceans have bilateral symmetry and a hard crunchy exoskeleton. Because the crustacean grows and the exoskeleton does not, crustaceans have to molt or shed their hard outercovering, exposing a new softer bigger covering that will harden in a few days.

LOBSTERS
There are two basic lobsters to be familiar with - the clawed lobster and the spiny lobster. Both are primarily scavengers. The clawed lobster has two different claws - a lighter faster shredder and a heavier more powerful crusher. The clawed lobster is more solitary because it is more aggressive. The spiny lobster does not have big claws, but can defend itself with its long whip like antennae. This lobster likes to congregate in groups and is not as aggressive. Both lobsters carry their eggs on the swimmerettes protecting them from potential predators.

Left: male ; Right: Female

CRABS - In general, you can tell the difference between boy crabs and girl crabs by looking at the shape of the plate on the abdomen. Boys have a thinner more pointy plate, girls have a wider more rounded plate because it is used to hold the egg mass. The mothers carry the eggs because not many predators will mess with them to get to the eggs.

• Blue Crabs are found in the Chesapeake Bay. They are very agressive, like to pinch, but are good to eat. They have a pointy-ended shell and swim fins. (you can kind of see the swim fins on the last leg of the crabs on the right)
• Spider Crabs have a rounder body shape, often a bumpy shell that will grow algae for camouflage, and longer more spindly legs. Spider Crabs include snow crabs and king crabs like the ones seen on Deadliest Catch. A decorator crab is a kind of spider crab that attaches stuff to its bumpy shell to blend in.
• Fiddler Crab males have one claw that is a lot bigger than the other. This is for impressing the ladies, and used to show dominance over other males. 
• Hermit Crabs have a weak exoskeleton and thus protect it with a stolen mollusc shell. They have adapted to this lifestyle and have modified back legs that hook on the inside to hold the shell on and one claw that is slightly larger to use as an operculum.

SHRIMP - miniature lobsters... use their swimmerettes to keep themselves moving - most Americans have never seen one with its head and legs still attached!

• Gulf shrimp are the ones people most people are familiar with because these are the ones we eat!
• Shore shrimp live in sea grasses, are fairly small and clear, and are not commercially harvested because no one would make any money.
• Snapping shrimp (or pistol shrimp) have slightly larger claws and can use them to make sonic waves to stun their prey with sound. 
• Mantis shrimp whack their prey with arms that can unfold and strike lightning quick. 
• Cleaner shrimp make their living eating parasites off of fish and other sea creatures. 

BARNACLES
If you look at a diagram, barnacles are like little shrimp glued on their backs with a white fence around them. They stick their feathery legs out to filter feed plankton. They are plankton for a while and once settled and glues onto a hard substrate never move again. This makes mating difficult, but the hermaphroditic barnacles have special talents. Gooseneck barnacles have a stalk that they attach to substrates with.

Nudibranchs - Sea Slugs

Nudibranch (naked-gills) are sea slugs that have lost the ability to make a shell over evolutionary history. They do however have some interesting adaptations to keep from getting eaten. Most nudibranch exhibit warning coloration because they are poisonous or have stingers - none that they make - they acquire them from the prey that they eat!

National Geographic did a great article a few years ago full of lovely photos. Both are linked here. Watch the video for a full-range spectrum of photos.

local bivalves

Most people do not know that there are freshwater clams and mussels in Lake Anna and that they can get as big as the palm of your hand. Nathan, a former student, did his Governor's School project about some of the habitat in the lake and I has asked him to bring in some of these beauties so we could get a good look at them. With the help of his brother, a current student, brought in three little clams for us to enjoy in class a few semesters back.

I found that taking pictures of them in the cup was not easy, but using the document camera, I was able to project an up close view of them onto the wall so that everyone could see the clams and their siphons in detail. Students were able to watch the clams in action while taking their practical. Now that may seem like an oxymoron - clams in action... but there was stuff to see.

You could clearly see the siphons and at times see particles being sucked into the siphons. I put some fish food in the cup and the suction power of the clams was enough to create a current that caused the fish flakes to swirl around in the top of the cup. In first period we were able to watch one of the clams use its foot to dig into the sand to sit upright with its siphons up.

So get to the Lake and have a look!

Cephalopods

Today students explored the wonders of cephalopods. Cephalopod means head-foot and includes octopi, squid, cuttlefish, and the chambered nautilus.

Cephalopods are characterized by their large well developed eyes, numerous tentacles, a parrot like beak in the center of the tentacles, and well developed chromatophores in their skin that allow them to change color.

We watched numerous videos today to see and understand how and why cephalopods make ink clouds, to see how an octopus can swim with jet propulsion or use its tentacles to crawl around, and we also saw how a octopus can eat a shark! Below is a video that I took at an aquarium that shows how an octopus uses its tentacles and suckers to move.


For more information about cephalopods, check out CephBase and the Australian Cephalopod Research page.
Students read a historical narrative about sea monsters and how those stories of the Kraken were based on squid sightings. We have known about the giant squid for several hundred years because of dead specimens and pieces found, but the first live one was not observed until 2005. Sailors used to think that the giant squid was much bigger because of a measurement error. Sucker marks on sperm whales were used to estimate size until they relaized that those marks and scars grew bigger as the whale grew.

Students then read a fictional account about a squid attacking the Jersey Shore (article pictured at left) and had to identify what parts of the stories were accurately portraying the squid and which parts were inaccurate.

Gastropods

Gastropod means "stomach foot" and includes all snails and anything else that makes one shell. Gastropods have one foot, one shell, and one siphon.

Some shells are spiral and have an operculum to act as a door for when they hide inside. The snail lives in the entire shell (all the way up into the top and retreats inside to hide when it feels threatened or exposed. The operculum blocks any would-be attackers and is made of a material similar to fingernails. These types of molluscs include whelks and moon snails.

Other shells are not spiral and the snail has good suction power so that predators have a difficult time pulling the snail off the rocks. These types of molluscs include slipper snails, abalones, and limpets.

Pearls

Pearls can be made by any mollusc that has a shell. I passed around my pearls and some shells that I have with pearls on the sides - not all pearls are free floating - they can be attached to the side of a shell. A mollusc makes a pearl to cover an irritating spot like a piece of sand that gets inside the shell. Pearls can be "glued" to the side of the shell or free to move inside the mollsucs shell. We prefer the "free" kind.

Any mollusk that produces a shell can produce a pearl. Nevertheless, naturally occurring pearls are rare, found in perhaps one of every 10,000 animals. The cultured pearl industry, which has flourished since the early 20th century, has developed techniques to greatly improve these odds. Indeed, more pearls are produced now than at any time in human history.( SOURCE This is a good website for lots of information on pearls)

Sally Sells Sea Shells

Students are in the midst of Unit 4 Molluscs busily learning about the different classes of Molluscs and trying to learn a variety of sea shells. Students lhave earned the basics about sea shells

• The shells found on the beach are from dead organisms.
• Any mollusc that has a shell, makes it shell.
• Sea shells are made of calcium carbonate.
• Shells are smooth on the inside because slimy molluscs don't want to rub their soft bodies on something rough. If they are smooth on the outside, then the mollusc also wears its body on the outside of its shell.

Today's cool mollusc was the chiton, an odd mollusc that has 8 overlapping plates held together by its soft squishy mantle, and the plates come apart when the animal dies. Chitons are built like armored cars and have great suction to stay on the rocky coast in waves and storms. They spend their days sliming around scraping algae. When pulled off a rock, it can roll into a ball to protect its squishy parts. More info can be found here.

Students also learned the four major classes of bivalves - clams, mussels, oysters, and scallops. Bivalves have 2 shells and 2 siphons, as well as adductor muscles to help keep their shells from opening for hungry predators. Bivalves include some of the more well know shellfish like scallops, clams, oysters, and scallops as well as a few like jingles, ark shells, and cockles. Pictured to the right are a clam (tan), oyster (grey), and mussel (black).

Mussels make byssal threads for attaching (so do ark shells and jingle shells) and scallops have eyespots to see predators. Oysters make cement to stick together and clams have a powerful foot for digging down and hiding.

Marine Ecology Biomes

Students have been learning all the different biomes that exist in the oceans. Most people have heard of coral reefs and think about the beach, but there are actually many different biomes in the ocean.

We finished class by discussing coral reefs and passing around coral skeletons made of calcium carbonate that I have collected on my travels and inherited from my grandmother. Each hole in the coral houses a polyp... and all the polyps make up the coral colony. So the polyps make up a superorganism. We then watched some BluePlanet and learned about some of their predators like the crown of thorns sea star and saw how the corals that sometimes look like rocks are able to attack and eat each other.

Today we started by discussing the kelp forest. Kelp forests are dominated by kelp that can grow to 300 feet tall. The kelp is held near the surface by lots of air bladders. Kelp forests are important because they provide a lot of substrate and habitat for organisms to live, hide and eat.

We also discussed sea grass beds. Sea grass is super-important for stabilizing the substrate and holding the sand down. This promotes water clarity and decreases turbidity. Nothing eats sea grass when it is alive except for manatees. Everything else eats it after the bacteria have decomposed it a bit.

One of the weird- est, but also most inter- esting is Whalefall. Whalefall is when a dead whale settles to the bottom of the ocean and organisms move in to feed on the carcass until even the bones are decomposed. Hagfish are a dominant scavenger as well as bacteria. It may not seem like a big deal, but this biome boasts over 160 species that are not found on the surrounding benthos. More info can be found at the link above, or here. Listen to a podcast here.

Deep sea benthos is another biome and it is pretty boring. Its a gooey squishy substrate populated by some dd scavengers, but there is not a high biodiversity and not a lot of food to eat.

Not all biomes are found at the bottom of the sea. Along coasts you can find rocky coasts, sandy beaches, salt marshes, mangroves, sea grass beds, kelp forests, and fouling communities.

I think fouling communities are really interesting... because all these organisms need is a hard substrate (surface) to stick on. This could be a dock, a pier, a boat, or anything that's in the water long enough. Most people have seen all the 'stuff' growing on the pole legs of piers and docks, but don't really think of the variety of organisms that grow there - or their importance. Most of these organisms are filter feeders and do a lot for water quality. They also break down the surfaces like scavengers... not something we want for our boats and docks we use, but important nonetheless.

 

Salt Marshes are one of the most productive ecosystems, but nothing eats the salt marsh grass when its alive... once the anaerobic bacteria break it down into black mush, then other organisms eat it.

Mangroves are trees that can grow in salt water. They have crazy prop roots or finger like roots called pneu- mato- phores that stick up out of the water so the tree can get oxygen during high tide. The roots provide a lot of substrate that a lot of fouling organisms will colonize and use as habitat.

Photic vs Aphotic is an odd one involving the light and dark zones of the ocean. Some organisms hide in teh dark aphotic zone during the day and migrate up to the surface (the photic zone) at night to eat the phytoplankton. Predators also migrate to eat the things that are eating the phytoplankton.

There is a lot of information to learn this unit. The Unit 3 Test is one of the hardest of the year.

Zonation

Today we discussed zonation in Marine Ecology. Zonation happens when organisms are adapted to a very specific set of conditions. Because some organisms are better adapted to these certain conditions, we see bands of organisms occupying zones. Today we talked about zonation and specifically how it affects the rocky coastline.

Students identified zones on rocky coast pictures and took notes on the material. Here is an example of a photo where the zones can clearly be seen by changes in dominant seaweeds. The Fucus would in the lower intertidal zone and the Pelvetia would be in the upper intertidal zone. It is easy to see the high water mark or where the high tide will reach. You can also see the lichens in the spray zone.

The spray zone is one of the hardest areas to live in because of the huge changes in salinity and temperature.

Seaweed

Students learned about the three types of seaweed. Seaweed and algae are the same thing and they are classified by pigment type - red, brown, or green. 

Red seaweeds are the most common, but we don't see a lot of them because they like tropical waters and deep waters. 

Brown algae is the most common seaweed on our coast, whereas green algae is the most common in the freshwater of Virginia. Students will make observations of seaweed to look for air bladders and other special adaptations. Air bladders help a seaweed stay near the surface to ensure adequate sunlight for photosynthesis.

There is also cyanobacteria - or the blue green algae.

Plankton!

We are learning about plankton! Plankton include organisms that drift through the seas that cannot swim and do not attach to the bottom. Plankton can be classified a variety of ways. The first way is to classify them by size. Microplankton and nannoplankton require a microscope if you want to see them because they are so tiny. Macroplankton are small, but you can see them without a microscope. Megaplankton are big enough to pick up and include things like jellies.

Another easy way to classify plankton is into plants and animals. Phytoplankton are tiny plants that photosynthesize and make their own food. Zooplankton (belong in the the zoo) and are animal plankton.

Plankton can also be classified as holoplankton and meroplankton. Holoplankton are plankton for their whole lives (forever) and meroplankton are only plankton for part of their lives. The meroplankton may be plankton when they are eggs, larvae, juveniles, all of those stages, or only some of those stages. Most of the invertebrates and fish in the ocean spend some time in their life as a plankton because it allows them to spread around the ocean and find new places to live. This photo is a meroplankton snail larvae that grows into a poisonous cone snail.This is my favorite website about plankton and it is where all my photos come from. Check out the other types of meroplankton.

Students have drawn their own plankton, tried to match meroplankton to the adult forms, and are currently designing plankton to compete in the Plankton Grand Prix - where the object is to sink slowly.

Keystone Species - Sea Otters

We talked about keystone species. Keystone species are important members of the food web because they help maintain biodiversity and keep everything in balance. An example is a sea otter. Sea otters eat sea urchins and keep their population in check. Trey loves sea otters - even though I keep telling him they are vicious and have scary teeth!

When the sea otters are removed (like when they used to be hunted for their fur), the sea urchin populations go crazy, eat all the kelp (as in many many 300 foot tall plants), and the loss of kelp leads to a drop in biodiversity because there is less food and habitat for the many other species that like to live in and on and among the kelp.

Look at these before and after food webs when the sea otter is removed from the kelp forest. (from this website)

Parrotfish

Parrotfish are part of the nekton because they swim. They are omnivores because they eat coral (animal) and algae (plants). This fish is a male because it is more colorful than its female counterpart. Some may consider this warning coloration because it will chomp on things that try to mess with it. An odd part of their niche is that the coral they digest is where most of the white sand in tropical locations comes from.

Mutualism, Commensalism, and Parasitism

We started class with a BrainPop on symbiosis and then went right into notes covering the same material. We did take a lot of notes today, but the subject matter is interesting and students were asking a lot of questions.

Mutualism is the relationship that is best understood because both organisms benefit - although the advantages are not often clear to us. Pictured to the left are an alligator and plover, eel and cleaner shrimp, and zebra and finch - all of these are cleaning relationships. The smaller organism eats parasites and gets a meal and the larger organisms will not eat it as well as get the benefit of being cleaner (less infection and disease). The bottom right picture is a blind bulldozer shrimp and a goby fish. They share a dwelling that the shrimp builds, and the fish lets the shrimp know when trouble is coming. (Photos from this cool blog)

Parasitism involves things that give us the heebie jeebies. These parasites take advantage of their host, usually feeding on the host, and benefit. The host gets no benefits and over the long term is harmed.

Commensalism is when one organism benefits and the other is unaffected. So one gets all these advantages from the other... but the other doesn't get a benefit from it and isn't harmed by it.

Here are some other fun photos of oceanic relationships. Identify some and turn them in for extra credit!

Camo and coloration

We discussed predator prey adaptations - specifically coloration. The first topic is camouflage. Flounder (like the ones pictured) have passive camouflage. Their bodies are patterned and it allows them to blend in with the background. Can you spot the flounder in these photos?

Active camouflage is when an organism can actually change the color of its skin to match a background or flash colors to confuse predators and prey. Watch the Kings of Camoflage video about cuttlefish in the sidebar for more information.

The photo above is from this cool website blog that archives photos of all kinds of animals that are camouflaged.

We also talked about other types of coloration like mimicry, flash, warning coloration, advertising, and sexual dimorphism. Students finished the day by reviewing coloration and coloring their own fishes.

Lifestyles and Feeding

Today in class we discussed different lifestyles. Organisms can be plankton and spend their lives floating and drifting. Nekton means they can swim. Benthic organisms, or organisms that spend their time on the bottom can be attached, can crawl, walk, and some swim - but if they swim they swim along the bottom and spend most of their time resting on the bottom.

Next we discussed eating. Producers don't eat - they can make their own food. Producers starts with P and so does Plants and PhytoPlankton.

Herbivores eat plants, Carnivores eat meat, and Planktivores eat plankton. Students worked on a worksheet sorting organisms into their varying lifestyles and eating preferences to finish class.

We technically finished class with a little Blue Planet - watching orcas practically beach themselves in an attempt (a successful attempt to eat baby seal lions on the beach). :)

Sand & Underwater Vehicles

Today we discussed sand and where it comes from, what its made of, what colors it can be, an how shape and size affect the texture. In Hawaii there are black, red, and green sand beaches that have been deposited from the weathering and erosion of volcanic rocks. In the Caribbean, you can visit white and pink sand beaches from the weathering and erosion of sand and coral.

Students used scopes and made observations of sand samples from Hawaii, Grand Cayman, Normandy France, Lake Anna, Lake Superior, California, and Virginia Beach. Adrienne's mom brought us some sand from her recent trip to the Carribean - THANKS! Students determined what the sand was made of, where it came from, how old it was, if it was on an active beach, a windy beach - all kinds of information can be collected from a simple sample of sand!


The rest of class was spent working independently on the seafloor features surrounding the United States and reading and answering questions about underwater vehicles. Submarines are larger than submersibles and carry more people and can go longer distances. ROVs and AUVs are robots like remote-controlled cars, but go underwater. ROV's have a tether (cord) connecting them to power and AUVs do not.

Plastic in the Ocean - Seafloor Features

Almost ninety percent of them are not recycled and quite a lot of them end up blowing and floating around the environment where they look gross but also pose a hazard to wildlife. Most students do not think about where their garbage ends up. If you'd like to see the presentation - click here. For more information about plastics in the ocean - check out this info from the Ocean Conservancy.

Today in notes we covered sea floor features. We discussed the definitions and identified them on maps and then answered some questions. Test yourself - can you identify the features to the right?