Plastics and the Sea floor

Almost ninety percent of plastic bottles 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.

Many people mistakenly think that the sea floor is flat. Well about 80% of it is called the abyssal plain and is relatively flat, but the sea floor has mountains and canyons just like the land we see everyday! We discussed the definitions and identified them on maps and then answered some questions. Test yourself - can you identify the features to the right?

Floating Stuff and Currents

Currents can be identified by their temperature, salinity, and density. Students identified which currents were warm and cold by looking at where they are coming from and then colored them appropriately.

Sailors have known about some of these currents for a very long time. Early explorers knew it took less time to go to Europe from North America and not the other way, even if they didn't know it was the slightly warmer, slightly faster Gulf Stream that was carrying them along. Scientists who study currents have historically dropped stuff into the ocean and recorded where it has turned up. Yes, those messages in a bottle can be useful.

Curtis Ebbesmeyer is one of the leading oceanographers in current research and he doesn't drop any bottles. Instead he tracks cargo that is lost overboard from large container ships in trans-oceanic crossings. He started with a cargo of Nike sneakers, but has also worked with plastic ducks (pictured), legos. pumice from volcanic eruptions, and wooden barrels. Mr. Ebbesmeyer is most famous for his research on the plastic ducks. Although many ducks, beavers, turtles, and frogs have been recovered, oceanic currents are carrying them further still...

Students practiced latitude and longitude by plotting some points of a cargo lost overboard and where some of the shipment washed up beaches, then they read articles and answered questions, and finished up by listening to a podcast interviewing Curtis Ebbesmeyer, the oceanographer who studies sneakers, rubber ducks, and other floating debris. You can listen to the podcast here.

In the interview, and in the readings, gyres full of floating plastic debris are discussed. Here is a map showing some of the locations of these gyres. Click on the picture to get a larger view. Here is an excellent website with more information and some nifty graphics. We will continue to discuss this in class. 

Light in the Ocean

Today students learned about light in the ocean and how far light travels down. The amount of light transmitted depends on the turbidity (clarity) of the water. Different colors of light travel different lengths. Blue travels the farthest, but red, orange and yellow do not travel far. Because red does not travel far, these organisms appear black.

After discussing bioluminescence (organisms that can produce their own light) we looked at brief video clip about it that is a little old and then a TED talk by David Gallo that is more recent. Gallo's talk showed the organisms in more accurate color and in motion. His talk also showed some amazing footage of cephalopods like cuttlefish and octopus performing magical feats of mimicry and camouflage. You should definitely follow the link and watch this video stream.

His talk was based on research by Dr. Widder. We looked at some of her photos and you can learn more about her work and see her presentation here.

When it comes to deep sea creatures - some bioluminesce and some don't. People are fascinated with the gulper eel, a four foot long eel that has a HUGE jaw. It has such a big mouth so that it can eat anything it comes in contact with because in the deep ocean, meals may be far and few between. More information about the gulper eel and other deep sea creatures can be found at Sea & Sky's Website.

Tsunamis

Today we discussed tsunamis, which fascinate most students. Tsunamis are caused by underwater earthquakes and they displace water. Displacement of water causes a large wave or energy to travel through the water, but it cannot be seen at the surface until the wave approaches shallow water. (Confused? Check out the diagram to the left) Because the wave is not felt in deep water, going out to sea is one option for escaping a tsunami, getting onto land with higher elevation is another option. There are places in Japan and Hawaii where fishermen went out to sea in the morning and when they returned, their villages had been washed away.

We discussed tsunamis and how countries around the globe are teaching native peoples to recognize the signs of a tsunami and setting buoys to measure if a tsunami is coming. Students decided that they were glad they didn't live somewhere where the threat of a tsunami is imminent... well except if the Canary Islands fall into the sea.

Most people are aware of the large tsunami that hit Japan last spring and the damage it caused to their coasts and towns. We discussed the damages and how powerful a tsunami can be. An interesting assortment of before and after tsunami pictures from Japan can be found here.

Pressure in the Ocean

Pressure is the weight of particles above you and increases with depth in water. Right now there is one atmosphere of pressure squeezing on all of us, but we are used to it, so we don't notice the difference. We may notice our ears popping when driving over Shenandoah or flying in an airplane when pressure decreases.

Water is 800 times more dense than air, so underwater, pressure increases dramatically. Pressure increases one atmosphere with every ten feet of depth, so all you need to do is dive down the deep end of the pool and you will feel an increase in pressure to two atmospheres (one for the water, and one for the air)

Scientists think it is funny to take styrofoam deep into the ocean because the pressure underwater will squeeze the air out of the styrofoam and "shrink it." Really it is just compressed and more dense. Here is a photo of what happens to styrofoam wig-heads and cups when taken down a few thousand feet, a change of several atmospheres of pressure. Ms J has some styrofoam cups (donated by a former student) that went 12,000 feet down on a submarine that are very similar. They used to be 12oz cups and now they are only about 4 inches high.

We did a quick demo lab with plastic cups and water to demonstrate how pressure increases with depth.

Greetings students, parents, and guardians. Welcome back to a new school year with Ms Jancaitis! Welcome to Marine Ecology! This blog has been set up to connect students, parents, and guardians with the marine ecology class.

 At Open House or in class, each student will receive a course syllabus, safety rules, and a breakage sheet. The safety rules and breakage sheet needs to be read and signed by both the student and parent guardian.

The course syllabus outlines what the course will be like, what topics will be covered, and course expectations. It also contains contact information. There will be a quiz on this syllabus and classroom procedures on Thursday.


The safety rules are rules designed to keep the classroom safe and orderly to maximize learning and prevent accidents and injuries. These rules need to be studied because there will be a safety test on Friday and infractions of these rules can lead to disciplinary action as well as low assignment grades. A breakage sheet is a contract holding students accountable for the items that are broken if the student is acting a manner that is unsafe for themselves or those around them.


Please have these papers signed and returned by Monday the 14th. Students not returning signed safety rules and breakage sheets will not be able to participate in labs and activities until the contracts are signed and returned. 

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. Sharks have internal fertilization and the male shark has two claspers for sperm delivery. These can be seen on male sharks protruding from the pelvic fin.

Shark reproduction is violent with males biting the female. As a result female shark skin is much thicker than the males so that this practice does not ham or kill her. She fights a little to ensure that only strong males with good genes are able to fertilize her eggs.

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.