Sunday, October 31, 2010

Fish Reproduction

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 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.

Wednesday, October 27, 2010

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.

Thursday, October 21, 2010

Crustacean and Echinoderm Costumes

Today in class we did our final review of crustaceans and echinoderms. Groups drew a random card and had 15 minutes to make a costume for one of people to wear. Materials included a stapler and a piece of paper. Mr. Straley stopped by in the middle of the fashion show and snapped this photo of Corrinn's crab walk (I am in the background wearing a barnacle hat). He posted this photo to his blog - you can check it out here.
Elijah is helping Moe with her Mantis Shrimp gloves

Tommy is helping Lindsey with her antennaes (and looking evil)

making feathery legs for the gooseneck barnacle

Lindsey's spiny lobster antennae is getting lots of help

Amanda is a decorator crab

Corrinn is a male fiddler crab

Courtney is a barnacle with feathery legs

Morgan is a sea cucumber complete with yellow tentacles

Friday, October 15, 2010


Today was POKING DAY! Which is just a more interesting title for Crustacean - Mollusc - Echinoderm Observation Day. I go to the grocery store in town and see what kind of seafood I can find and the students make measurements and observations and see some of the organisms we've been discussing first hand.

It does smell a little bad.... but it is pretty fun, and the students do learn a lot. Here are some of the photos from today. 

Corrin and Rachel with Echinoderms (check out Corrin's cool new do)

ready to learn

shrimp with heads and super long antennae

ouch it's got me!

Kaitlin and the horseshoe crab

Jeremiah and the octopus

Kaitlin, Michelle, Bruce, and Jess at the Crab station

Alex, Tommy, and Lindsey at the lobster/crawdad station measuring claws

Bruce held the octopus (I think because of peer pressure)

More peer pressure for Amanda and Delafayetter

Cruella has nothing on Carlton and the shrimp heads :)

Harley and the crab get to know each other
My apologies for not turning any of them... sorta in a hurry. I have a feeling some of these might end up on Facebook and that is OK with me. :) Have a FAB weekend.

Nate and the octopus, demonstrating something

This photo makes me laugh.

Brittney and the blue crab (it's a male)

Meet the shrimp (via Carlton) - BEST PHOTO of the DAY

Saturday, October 9, 2010

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.

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.
  • 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 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. 

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.

Monday, October 4, 2010

Finishing up Molluscs

Today is the shell practical for Unit 4 on Molluscs. Students will get a cup with a question and a shell and see what they remember about all the molluscs covered in this unit. Most students enjoy the challenge of this unit even though it is a lot of information to remember. The benefit of the practical is that it really cements the knowledge into their brains so the next time they go to the beach they will know what seashells they are finding.

Students took the Unit 4 Mollusc Test on Friday and did very well on it. These are the last assignments that will be included on the nine weeks grade.

Computer Lab Etiquette

You are in the computer lab to do work for this class. If you are not doing work, then we will have problems.

Do not pack up early. Work until the bell or until MsJ says.

SAVE OFTEN. And if you save to a key, also save it to your number. If you lose it, you will have to do it again.

If MsJ asks for your attention, stop what you are doing and listen to what she has to say.

You may watch videos about your organism through reliable websites.

You may listen to music through the computer if you have your own headphones. Rule1 MsJ cannot hear it. You get one warning. Rule2 Turn it on and listen – no million clicks and constant changing. Take both ear phones out when MsJ is talking.