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Teacher Resource GuidePreferred Activities
Education Outreach With Generous Support from theMaxwell H. Gluck Foundation
Complete Teacher Guide available at www.nhm.org/seamobileAlso available on Seamobile Resources USB
Odds and Ends
pre-visitC
lassifying Creatures
Procedure:1.) Discuss with students different ways of grouping objects. Ask why it is important to group objects. You might introduce a dichtomous key as one way of grouping and identifying things. Introduce the term “dichotomy” (division into two parts, groups or classes) and show how this is important in this kind of classification scheme.
Example: The people in your classroom can be grouped into categories of clothing. One couplet for this might be: People who are wearing a blue shirt. People who are not wearing a blue shirt.
2.) Divide the students into teams of two or three and give each team a bag of Odds and Ends, the Odds and Ends Worksheet, and a dry erase marker.
3.) Students should choose one item from the bag and follow the key in order to “identify” the object. After making the appropriate choice in each couplet, the team will follow the directions on the right hand side of the key until they have identified the object with a particular letter. Students can write the object name next to the appropriate letter on their worksheet, or copy this information into a notebook.
Key Concept:Students are introduced to a common method of scientific classification called the dichtomous key. They will use this method on a collection of everyday items. The goal of this activity is NOT to identify these objects, but rather to use a dichotomous key correctly.
Background:Scientists use keys to help identify and classify plants and animals. By organizing specimens based on similar characteristics, scientists can better understand how these species might be related to each other on an evolutionary level. Keys can come in different formats - some are used to identify organ-isms into larger categories, such as kingdoms or phyla, and other are used to distinguish among closely related species.
A dichotomous key presents the user with a series of positive/negative statements relating to distinct characteristics of the specimen.(”The animal has a backbone/”The animal does not have a back-bone”). These statements are sometimes referred to as couplets. The couplet is usually an either/or choice. The specimen is correctly identified when one makes the appropriate choice for each set of characteristics in a series of consecutive steps, similar to a flow chart.
Guided PracticeFor using a Dichotomous Key - “Odds and Ends” activity
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More Information - for using a dichtomous key - “Odds and Ends” activity
Teaching Tip:Students often “switch” their items as they proceed through the key, choosing an item that matches the positive statement. For example, a student classifying a paperclip, after the statement “Object not made of metal,” might drop the paperclip and pick up a toothpick since it makes the statement true. Ask students to close their bag after choosing an item. The bag should remain closed until the group has completely finished identifying the object.
Materials:Odds and Ends activity set(contains 10 small bags)
Each small bag contains 11 items:- small metal paperclip- large metal paperclip- plastic coated paperclip- wooden clothespin- toothpick with plastic fringe- small sponge- metal jack- garden hose washer- penny- plastic straw- pencil top eraser
Odds and Ends Student Worksheet(10 laminated copies)
Activity Time:30 minutes
Process Skills:ComparingOrderingCategorizing
Odds and Ends
Student W
orksheet
choices directions1. Object made of metal Object not made of metal
2. Wood Not wood
3. Plastic tip No plastic tip
4. Rubber Not rubber
5. Pointed Not pointed
6. Rectangular shape Tube shape
7. Painted Not painted
8. Flat Not flat
9. Object copper color Object silver color
10. Greater than 4 cm Less than 4 cm
Go to couplet 7Go to couplet 2
Go to 3Go to 4
Object aObject b
Go to 5Go to 6
Object cObject d
Object eObject f
Go to 8Go to 9
Object gObject h
Object iGo to 10
Object jObject k
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1. Living Go to couplet 2 Not living Go to couplet 3
2. Roots Object D Tree No roots Go to 3
Example:
Odds and Ends - Student WorksheetIn this activity, you will use a dichotomous key to sort some everyday objects.
How to Use This Key1. Choose one item from your plastic bag. Close the bag.2. Begin by reading the first set of choices, called a couplet.3. Decide which statement of the pair best describes your item.4. Follow the directions on the right hand side of the key.5. When your choices bring you to an object letter, write the name of the object on the blank line.6. Repeat with a new object until your team has identified all 11 objects.7. Compare your answers with the Answer Sheet when done.
Odds and Ends
Answ
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Answer Key Odds and EndsObject aObject bObject cObject dObject eObject fObject gObject hObject iObject jObject k
tooth pickclothes pineraserrubber washerspongeplastic strawpainted paper clipjackpennylarge paper clipsmall paper clip
Odds and Ends
Answ
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Object gObject hObject iObject jObject k
painted paper clipjackpennylarge paper clipsmall paper clip
Invent a Key for Echinoderms
pre-visitC
lassifying Creatures
Invent A Key for EchinodermsStudents will make observations and use their understanding of classificationto create a dichotomous key which will help distinguish several echinoderms.
IntroductionEchinoderm is taken from a Latin term that means “spiny skin.” These animals live underwaterand include sea stars, sand dollars, sea cucumbers, sea urchins and brittle stars.
Procedure1. If you have not already completed the activity Odds and Ends, consider using some of the same introductory discussion recommended for that activity.
2. Divide the class into teams of 2 to 4. Give each group an Echinoderm photo set and a worksheet.
3. Sudents can begin by examining the cards and thinking about different characteristics they might use to group the objects (body shape, color, number of arms, etc.)
4. Once the students have had a chance to think about grouping, ask teams to devise a dichotomous key for their echinoderms on the worksheet provided. Remind them that they will write couplets, which basically provides a choice between two options. Example: Animal has a shell. Animal does not have a shell.
5. Encourage students to follow one branch of classification to its completion, rather than looking back at the whole set of photos all at one time.
6.Once students have completed their key, ask each team to present their classification scheme to the class. As they describe their choices, ask other students to consider how their dichotomous key was different. Alternatively, you may ask groups to exchange keys and see if they can classify the pictures using the other team’s key.
Alternative AssignmentSome students may be able to organize their key better in a more graphic mode. Consider asking students to choose which mode (written text or branching diagram) they prefer. If students choose to create a branching diagram, remind them to describe the characteristics at each branch point.
Extensions1. After students have created their own keys, you might share with them the actual names of these echinoderms. Notice that some are actually the same species, even though they look quite different.
SpeciesABCDEFGH
Common Namepurple sea urchinbat starsunflower starbrittle starbrittle starsea starsea cucumbersea cucumber
Scientific NameStronglyocentrotus purpuratusPatiria miniataPycnopodia helianthoidesOphiothrix spiculataOphioderma panamensePisaster giganteusParistichopus parvimensisParistichopus parvimensis
2. Ask students to create a classification system for more common “species” such as snack foods, writing utensils or types of shorts worn by students in the class.
MaterialsSet of 8 Echinoderm Photos*(one per team)Invent a Key worksheet*photos are pages 69-72
Activity Time40 minutes
Process SkillsObservingCommunicatingComparingOrderingCategorizing
Teaching Tip: There is no one right answer for this activity. Each group will interpret their observations differently. Assessment should be based on student explanation and the effectiveness of their choice of couplets.
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Student Worksheet Invent a Key for EchinodermsUse the spaces below to write couplets which group the echinoderms (onthe picture cards) into smaller categories.
1.
2.
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4.
5.
6.
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Echinoderm Photos - Appendix DThe eight photos on the following pages can be used with the activity Invent a Key for Echinoderms.Each team of students will require one complete set of photos species A through H
A
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F
G
H
Squid Dissection: From
Pen to Inkpost-visit
Life Beneath the W
aves
Squid Dissection: From Pen to InkThrough squid dissection, students will examine some of the unique features which have allowed squid to adapt and thrive in Southern California waters and through-out the world. Students will identify the internal and external anatomy of the squid. To avoid being wasteful, the activity ends with a Calamari Cookoff!
IntroductionOne of the main objectives of this activity is to introduce students to dissection, an important part of science discovery that can help us better understand how life works. It is important for students to see the role that dissection plays and develop a sense of responsibility and respect for the animal that they are using as a learning tool.
After the students finish their dissection, the impact of squid in their daily lives should be discussed. Squid are an important food item to many people throughout the world. With this in mind, the students have the opportunity to prepare and cook their squid at the end of the lesson.
Dissection Procedure1. Begin the activity by asking students what they know about squid. Encourage questions, possibly making a list on the board that you may be able to answer as you continue through the dissection.
Possible questions (relating to anatomy) might include:How does it eat? What does it eat?How does it swim? How does it steer?How does it protect itself?Is it male or female? How can you tell?Consider giving students a copy of the information sheet,About Squid
2. Using one squid for demonstration, and the worksheet Squid: External Anatomy, begin to discuss the external anatomy and relate the features to the way the squid functions in its marine environment. Important features include the arms and tentacles, for hunting and mobility; the fins, for stabilizing and turning the squid while swimming; and the chromatophores, which can change color to aid in finding a mate, or in warning other squid.
3. Provide each student, or pair of students, with a squid on a paper plate. Use newspapers to cover the area where they are working.
4. Ask students to identify the external anatomy of the squid. Make sure they count the number of arms and tentacles. Have the students pull back the arms to locate the beak. As they identify the features, they can fill in the spaces on their external anatomy worksheet.
5. After the students have had the opportunity to explore the external anatomy, they are ready to begin the dissection. Instruct the students to position the squid on the plate with the siphon facing up.
6. Distribute scissors. (These are the easiest tools to work with; scalpels are not necessary and can be dangerous). Ask students to make one long cut from the bottom of the mantle, above the siphon, to the tip of the mantle next to the fins. Be sure to instruct the students to lift up with their scissors when cutting so as not to cut into the internal organs of the squid.
Materials forDissectionfresh or frozen whole squid(Loligo opalscents) available at a fish market or grocery store(one per student or team)Clean dissection scissors or basic student scissors(one per student or team)Paper platesPaper towelsSquid Anatomy worksheets
Materials for Food Preparationportable fryer and oilcontainers for milk and flourmallet (for tenderizing)seasoned flourbuttermilkcocktail sauce
Activity Time40-50 minutes
Process SkillsObservingCommunicatingComparingRelating
Teaching Tip: Depending on the class, you may wish to demon-strate the entire dissection for the class before asking them to do it. A video camera or flexcam attached to a monitor could make this even more effective.
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7. Spread the mantle open and have the students identify the internal anatomy using the Squid: Internal Anatomy worksheet. Begin with locating the feathery gills and following those to their base to locate the hearts. Challenge students to find the liver, ink sac and siphon.
8. When the students have located all of the internal organs, they can remove the arms and internal organs from the mantle. Students should pick up the squid by the arms and while holding the mantle in the other hand, pull to separate the arms from the mantle. If done properly, the arms and internal organs will come off in one piece. Students may notice a thin shell-like pen inside the mantle. They can pull the pen out of the mantle. (They made need to snip it out using scissors).
9. While students are dissecting the squid, consider asking some questions to encourage discussion about the squid.
Where does the squid fit into the marine food web?What adaptations does the squid have that allow it to survive?Can you think of other animals that play a similar role in other ecosystems?Have you ever used a squid for food or fish bait?
Calamari Cook-Off1. Have the students remove the fins by grasping the mantle in one handand the fins in the other and pulling to remove the fins. Then have the students clean the mantle by removing any of the excess skin.
2. When the mantle is clean, have the students cut the mantle into strips. Once the strips are cut, have the students tenderize the squid by pounding it a few times with a clean block or meat hammer.
3. The students should first coat the squid strips with buttermilk, and them roll them in the seasoned flour mix. The teacher can then drop them carefully into the preheated deep-fryer and then let them cook until they curl up and float to the top of the oil; approximately 1 minute. The cooking should be done by an adult to prevent burns or other injuries.
4. Garnish with cocktail sauce and enjoy!
Squid Dissection: From
Pen to InkE
xternal Anatom
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ChromatophoreSkin cells containing pigment. Some animals, like squid, ”move” pigment and reorient reflective plates inside chromatophores to change color.
EyeSquid have well developedeyes that allow them to see almost as well as people! Cones within the eye even allows them to see color.
ArmSquid have 8 arms covered with suction cups.
Suction CupThe suction cup helps the squid hold onto food.
FinThese help squid change direction when swimming.
MantleThis is the main part of the squid’s body - all of the organ’s are inside.
PenThe squid is related to other shelled animals like clams and snails. The pen is all that is left of the shell the squid’s ancestors once had.
TentacleThe tentacles are longer than the arms and have suction cups only at the tips. These are used to pass food to the shorter arms and then to the mouth.
External AnatomySquid Dissection
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Student Worksheet Squid Dissection: External Anatomy
Squid Dissection: From
Pen to InkInternal A
natomy
Internal AnatomySquid Dissection
CecumThis is part of the digestive system. Processed food is absorbed into the blood here.
HeartsThese are used for blood circulation.
LiverThis helps with digestion.
SiphonThis tube squirts out water so that the squid moves like a jet plane.
BeakThe squid mouth parts resemble abird’s beak.
Nidamental GlandThis is a female reproductive organ. It provides a protective coating for the eggs.
GillsThese are used to absorb oxygen from the water.
Ink SacThe squid releases ink from this gland in times of danger. The ink also pushes through the siphon.
BrainThe squid’s brain is highly developed for an invertebrate.
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Student Worksheet Squid Dissection: Internal Anatomy
About Squid Q
uick Info:
About Squid The squid is one of the most highly developed invertebrates.Some of the animal’s structures illustrate the ways in which the squid has adapted to life in the ocean. Its streamlined body and “jet propulsion” which occurs as the squid squeezes water out of its body through the siphon, make the squid a fast, active predator. This animal also has a very good defense mechanism.
Squid can be as small as athumbnail, or as large as house.The giant squid, Architeuthis, canmeasure 60 ft. in length and weigh three tons!
Squid have ten arms which are wrapped around the head. Eight are short and heavy, and lined with suction cups. The ninth and tenth are twice the length of the others, and are called tentacles. Suction cups are only on the flat pads at the end of the tentacles.
Squid feed on small crustaceans: fish, marine worms, and even their own kind! They use their tentacles to quickly catch their prey, which is pulled in by the arms and down to the radula, or beak, which uses a tongue-like action to get food to the mouth so it can be swallowed whole.
Squid are a major food source for many fishes, birds and marine mammals.
After mating, a female squid will produce 10-50 elongated egg strings, which contain hundreds of eggs each. In many species, the parents will soon die after leaving the spawning ground. The egg strings are attached to the ocean floor, are left to develop on their own, and hatch approximately ten days later.
All mollusks have a soft body with a special covering called the mantle, which encloses all of the body organs such as heart, stomach and gills.
Squid are an important part of the ocean food web. Squid are gaining popularity as a food source for humans around the world. Overfishing is a growing concern because there are no regulations on squid harvesting.
Squid produce a dark ink that they use to escape from predators. When a squid is startled, the ink is released through the anus, and the cloud of inky water confuses the predator while the squid swims away.
Southern California squid populations spawn mainly in the winter (December to March). Squid are seined (netted) commercially at their spawning grounds. About 6,000 metric tons are taken yearly for human food and bait.
lined with suction cups. The ninth and tenth are twice the length of the others, and are called tentacles. Suction cups are only on the flat pads at the end of the tentacles.
Squid feed on small crustaceans: fish, marine worms, and even their own kind! They use their tentacles to quickly catch their prey, which is pulled in by the arms and down to the radula, or beak, which uses a tongue-like action to get food to the mouth so it can be swallowed whole.
Squid are a major food source for many fishes, birds and marine mammals.
After mating, a female squid will produce 10-50 elongated egg strings, which contain hundreds of eggs each. In many species, the parents will soon die after leaving the spawning ground. The egg strings are attached to the ocean floor, are left to develop on their own, and hatch approximately ten days later.
Squid are an important part of the ocean food web. Squid are gaining popularity as a food source for humans around the world. Overfishing is a growing concern because there are no regulations on squid harvesting.
Squid produce a dark ink that they use to escape from predators. When a squid is startled, the ink is released through the anus, and the cloud of inky water confuses the predator while the squid swims
Southern California squid populations spawn mainly in the winter (December to March).
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dBackgroundWhat are transects and what can they tell us?Transects are simple ways of estimating population density, or the number of organisms living in a given area. There are various methods of conducting transects (such as random sampling and line transects), but they all follow a similar pattern. First, a small representative section of the study area is chosen. Then, smaller sample areas, referred to as plots, are established. In a line transect, these plots could be either touching or intersecting the line. The shapes of the plots are usually circles or squares of equal size. Each plot is then examined, and the numbers of individuals of the target species are counted. The total number for all plots are then averaged , giving you an aver-age density for the area of your plot. This can then be used to determine the average population density of your entire target area.
What does population density tell us about habitat health?In general, in increase in population density of a given species indicates that the area is favorable to that particular species. If the density of all organisms increases, or remains stable over time, this would indicate a relatively healthy habitat - one that is able to maintain a large population. How-ever, an increase of one population, with decreases in others may indicate problems with the habitat. It may indicate that one species is intensely predatory on other species, or that changes in the habitat favor one species over another. If all species populations decrease over time, this would tend to indicate major problems with the habitat. These problems could be natural, such as a depletion of resources due to overpopulation or disease breakout in the area. Of course, the prob-lems also could be man made, such as pollution or overharvesting.
How can we interpret the data?There are many difficulties in interpreting species density data, especially with animals. The major problem is that, in most cases, animals tend to move. The assumption is that they will move into or out of other plots, and the average will remain pretty much the same. The fact is though, that animals rarely move in a uniform manner, and the numbers may vary greatly from sample to sample. Two ways researchers can try to account for the error are (1) using large area sample plots, and/or (2) using many plots along the transect. This way, moving animals will be more likely to stay in a sample area, or move into another sample area.
Seasons must also be taken into account, since many organisms will show natural seasonal fluc-tuations. Samples taken in spring may have completely different numbers from those taken in late summer. Other issues that could confuse the interpretation of these data would include natural population changes due to predators and disease, or predation by migratory species. Miscounting or misidentification of species could also drastically alter the totals. The best way to solve most of these difficulties is to take many frequent samples. Yet, this introduces new difficulties; namely lack of time, money and experienced researchers.
Making Sense of it AllHow can scientific data help us better understandwhat is happening in a marine habitat?
Completing the Seam
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NOTE: THIS ACTIVITY SHOULD ONLY BECONDUCTED AFTER THE SEAMOBILE VISIT!
MaterialsData Summaries handout(at least one per team)Research Ques-tions worksheet (optional)
Activity TimeVaries
Process SkillsCommunicatingRelating Inferring
Completing the Seamobile InvestigationStudents can complete their Seamobile investigation by making a hypothesis using the data they have collected and supplemental information.IntroductionThis activity is designed to allow students to complete the Seamobile investigation following their visit to the truck. As the program is designed for a range of student grades and abilities, there are occasions when student teams are unable to complete the entire Seamobile program in the allotted time. This activity provides the necessary background (for students and teachers) for students to complete their investigation.
In the Seamobile, student teams collect data from ome of five different study sites. A computer database provides details for some of the key species at each of their sites. Once they’ve learned about these key species, they examine video still frames of their study site to count the animals or plants found in the area. They then compare this data to previous data collected twenty years before. In most cases, students discover that the numbers are different compared to twenty years ago. Students are asked to think about what might be causing these numbers to change over time. The mission ends with the students making a hypothesis relating to the changes in species populations, based on what they’ve seen and the data collected.Procedure1. Because each student team works at a different pace, some teams will be further along (or finished) compared to others. First establish where the students are in the investigation. This will give you an idea of how much more time you will need to complete the program.
2. Distribute the Data Summary page appropriate for each group’s study site. (All groups do not need information from all sites). Encourage students to read through this information and think about what this data tells them about their site.
3. In some cases, the species count taken by the group may not match the present species count listed in the data summaries. Advise students to use the data they collected on the Seamobile when answering their questions.
4. Each student should have returned from the Seamobile with a “Researcher’s Notebook.” Near the end of the notebook are three research questions. Ask students to complete these, based on the data they’ve collected and information from the data summaries. These questions are also found on the Research Questions worksheet.
5. Once students have answered questions, ask each group to present their findings, based on the research questions. By the end of each presentation, students should provide a possible reason for the changes going on in the habitat at their study site.
6. You may refer to the Possible Hypotheses page to wrap up the investigation. It includes a list of possible explanations for the changes observed and recorded by students at each of the Seamobile’s study sites. Understanding the interactions of plants and animals with their environment is a complex and difficult process. The hypotheses described for each site are probably the most reasonable, given the data available. However, students should under- stand that there may be additional factors which are impacting these sites and that better predictions would require additional research.
Extensions1. Ask students to create a poster presentation of their findings. Their poster might depict the interrelationships between the species in the habitat, as well as their hypothesis that accounts for the changes in populations in the habitat.
2. You might consider using this activity with classes that HAVE NOT participated in the Sea- mobile. The data sheets here provide much of the data necessary for students to begin to understand how we study habitats and make hypotheses regarding what may be impacting those sites.
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Student Worksheet Completing the Seamobile Investigation
1. Describe any changes that have occurred at your study site over the past ten years. Think about how the area may have changed and how the numbers and types of species living there may be different
2. What kinds of environmental problems might be affecting the plants and animals living in the habitat you’ve studied? There may be different problems for different species - try to mention as many as you can.
3. Based on all data your team has collected, make a hypothesis (an educated guess) that explains what is causing changes at your study site. Be specific in your explanation. Use your notes to help you.
Completing the Seam
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Data Summary Station 1
Habitat Kelp Forest
StudySpecies
SiteDescription
Garibaldi, Giant Kelp, Kelp Bass, Senorita
This site is located off the coast of Catalina Island, a popular tourist area surrounded by miles of kelp forests. These undersea forests provide habitats to over 800 different marine species. The kelpprovides both food and protection to many different types of marineanimals, from the ocean floor to the water’s surface. Kelp is helpful tohumans and is harvested for use in products such as ice cream, toothpaste, and some medicines.
Transect Count Data
Impact On SpeciesSpecies present count count from10 years ago
Senorita
Kelp Bass
Garibaldi
Giant Kelp
Senoritas use the kelp forest to hide frompredators. As cleaners, they also rely on theother fish living in the kelp for food.
Since kelp bass prefer to live where there is some sort of structure (kelp forests, oilplatforms, pilings, etc.), removing thatstructure may cause the fish to move to a different habitat.
Garibaldi were once threatened by humanover-collection. However, they are nowprotected by state law, making it illegal tocatch or spear any garibaldi. Garibaldidepend on the animals that live within thekelp forest for their food. Without the kelp,they would be forced to look elsewhere forfood.
The giant kelp creates a unique habitat formany marine species. Destruction of thekelp forest would force the animals to leavethe area in search of a new habitat, ifavailable. Scientists are often unable to figure out the exact causes for thedisappearance of a kelp forest. Perhaps it iscaused by severe winter storms with strongwaves that pull kelp up by its holdfasts. Itmay be the warm water temperatures causedby El Nino causing the kelp to wilt and die.Sewage and polluition can also destroy akelp forest by covering rocks with slime orsludge, preventing new kelp from attaching.
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Impact On SpeciesSpecies present count count from10 years ago
HabitatStudy
SpeciesSite
Description
ContinentalSlope
Basket Star, Lingcod, Rockfish, White Anemone
This site, near Catalina Island, is a deep water habitat. Themixing currents at this location create nutrient-rich water fullof food for the marine life. Lots of food means lots of fish inthe area too. The large number of fish brings many fishermen(and boats) to the area during the fishing season. Commercialfishing and tourism also occur in this area.
Rockfish
Basket Star
WhiteAnemone
Lingcod
7 55
10 15
1 12
6 8
Rockfish are a favorite sportfish. Rockfishdo not migrate and many spend their adultlife in one area, making them easy targets forthe fishermen.Basket stars are rarely caught by fishermenfor food. Deep water trawl nets used to catchbottom fish can accidentally catch, move,injure or even kill basket stars as the netdrags along the bottom.
Lingcod are prized for food and are alsovery popular with fishermen. Off SouthernCalifornia, commercial fishermen will alsocatch large numbers of these fish in gill and trawl nets.
White anemones are not commonlycollected by people for any reason. Theyreproduce quickly, so the few that are collected are rapidly replace. However, theweights of trawl nets can damage or killanemone as the nets are dragged across thebottom to catch fish.
Data Summary Station 2
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Completing the Seam
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Data Summary Station 3
HabitatStudy
SpeciesSite
Description
Transect Count Data
Impact On SpeciesSpecies present count count from10 years ago
RockyBottom
Moray Eel, Opaleye, Red Sea Urchin, Warty Sea Cucumber
This site is located off the coast of Palos Verdes, near thelargest sewage treatment plant in Los Angeles County.Before pollution control was improved, this plant collectedand discharged pesticides and other chemicals from localindustries into the ocean. Oil, debris, and other waste arestill washed into the ocean from streets and parking lotsduring storms. Runoff during heavy rains can also causethe treatment plant to overflow, forcing incompletelytreated sewage into the ocean
Red SeaUrchin
Warty SeaCucumber
Opaleye
Moray Eel
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If the food source of the red sea urchin isnot readily available in an area, the urchinpopulation may be in danger since they arenot as mobile as other marine animals andcan not easily relocate to another habitat.
Some bottom feeders like the warty seacucumber have become tolerant of pollutantsin the ocean sediments where they eat andlive. However, if poisons collect in the tissuesof the cucumber, there may be problems foranimals that try to eat it.
Opaleye feed primarily on kelp, but will alsoeat some small invertebrates. Toxins mayaccumulate in these fish if they eatcontaminated invertebrates. Also, pollutedareas that cannot support a healthy kelp bedseverely affect the number of opaleye.
Moray eels reproduce in the warmer watersof Baja, Mexico and become permanent residents of the southern California waters once they mature. Once they are settled intotheir new habitat and become part of thelocal food web, they may be accumulatingtoxins in their bodies from the food they eat.
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HabitatStudy
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Description
Data Summary Station 4
Sandy Bottom
California Spiny Lobster, Halibut, Horn Shark, Kellet’s Whelk
This site is located at the entrance to the Los Angeles/LongBeach Harbor. The harbor is one of the world’s largest withvery heavy traffic. Shipping lanes are designed in and out ofthe harbor, much like driving lanes, to control the flow of theships. To make sure that the ships can enter the harbor, theocean bottom is frequently dredged, or dug up, to make a clear passage. Dredging severely disturbs the harbor’ssandy bottom
Horn Shark
Halibut
CaliforniaSpiny Lobster
Kellet’sWhelk
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10
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12
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Horn sharks are “bottom dwellers.” Disturbingthe ocean floor may impact or destroy theother animals like clams or snails that the horn shark comes to feed on. This may forcethe shark to look elsewhere for its meals
Halibut are also bottom dwellers, spendingmost of their time on the sandy bottom inrelatively shallow waters off the Californiacoast. Changes to the ocean bottom, such asdredging, can cause problem for halibut bydestroying their habitat or displacing theanimlas that the halibut feeds on.
California Spiny Lobsters often search thesandy bottom areas for food at night. Algaeand most of the other food sources for thelobster live on the ocean bottom and aresensitive to changes that might disturb thearea. If no food source is available, thelobsters will move to other areas to hunt.
Often found on shallow bottom areas, Kellet’s whelks are scavengers. Fishing vessels in coastal areas often dump their waste fish parts and accidental kills back into the ocean before docking in the harbor. This trail of decaying and injured animals on the ocean floor can be very attractive to the whelks.With few predators and plenty of food,their population can grow very quickly.
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HabitatStudy
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Impact On SpeciesSpecies present count count from10 years ago
ContinentalShelf
Box Crab, Spiny Brittle Star, Sunflower Star, Giant Pacific Octopus
This deep water site is located off the coast of Orange Countynear Corona Del Mar. About five years ago, a ship spilled itscargo of copper powder near this site. Copper is a heavymetal and is known to be particularly toxic to many marineorganisms. The powder eventually settled to the bottom, andhas become part of the ocean floor sediment.
Box Crab
SunflowerStar
Spiny BrittleStar
Giant PacificOctopus
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Like many bottom dwellers, box crabs aresensitive to pollution from runoff oraccidental spills which accumulates on theocean floor. Some heavy metals, likecopper, may actually interfere with the crab’sability to use oxygen.
Sunflower stars are not particularly sensitiveto pollution themselves and are not impactedby human harvesting. As long as their foodsource of brittle stars, sea urchins and otherinvertebrates is available, sunflower stars will survive.
Scientists have discovered that the numberof some species of brittle stars dropssignificantly in polluted waters. As you movefurther and further away from the pollutedareas, these brittle star populations begin toincrease. The exact reason of how thepollution affects the brittle stars is notclear - scientists are still studying thisproblem.
The Giant Pacific Octopus is collectedcommercially as a source of food for humans.Their survival also depends on the health oftheir ocean habitat. Chemical pollution, fromdumping or accidental spills, often settles tothe sea floor, where it accumulates in thebodies of the marine animals, like clamsand lobsters (and even octopus). Thesepoisonous chemicals may kill theseanimals, or simply make them poisonousto other animals that eat them.
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Possible Hypotheses Below is a list of possible explanations for the changes observed and recorded by students at each of the Seamobile study sites. Understanding the interactions of plants and animals with their environment is a complex and difficult process. The hypotheses described below for each site are probably the most reasonable, given the data available. However, students should understand that there may be additional factors which are impacting these sites and that better predictions would require additional research.
Site 1 Kelp Forest HABITAT DESTRUCTION These undersea forests located near Catalina Island provide habitats to over 800 different marine species. Destruction of the kelp, whether caused by man or nature, forces these animals to relocate and find shelter and food in other areas. (Students need not speculate the cause of the kelp loss-rather just understand its impact on the habitat.)
Site 2 Continental Slope OVERFISHING This location, on the west end of Catalina Island, is an area of mixing currents and deep water upwelling, creating and maintaining nutrient rich water. The high level of nutrients means there is much food in the area for fish. In this case, lots of fish means lots of fishing. During the fishing season, large numbers of boats and sportsfishermen can be found in this area. Commercial fishing also takes place in the area, involving large gill nets (nets that catch fish by entangling their gills) and trawl nets (nets towed behind boats, often moving on or near the bottom of the channel). Excessive fishing may significantly alter this community.
Site 3 Rocky Bottom COASTAL RUNOFF
The site is located off the coast of Palos Verdes, an area known for old deposits of pesticides like DDT and significant surface runoff. Years ago, pesticide manufacturers dumped chemical waste into the ocean and
it has now become part of the ocean sediment. The site is also located near a County water pollution control plant wastewater from over 4 million people a day is treated and released into the ocean. These forms of pollution may be responsible for poisoning local species or killing their sources of food or shelter (e.g. southern sea palm) through water or sediment contamination.
Site 4 Sandy Bottom HARBOR OPERATIONS This site is located at the entrance to the Los Angeles Harbor. This area is subject to dredging operations which maintain clear passage for ships entering and leaving the harbor. Dredging severely disturbs the sandy bottom environment. Also, an unusually high number of dead and decaying fish litter the ocean bottom, possibly due to these dredging operations or the actions of commercial fishermen dumping their fish waste parts or unwanted catch before entering the harbor. This may be contributing to an increase in the number of scavenging species (like the Kellet's whelk).
Site 5 Continental Shelf COPPER SPILL
This deep water site is located off the coast near an area where a ship spilled its cargo of copper power nearly five years ago. Copper is known to be particularly toxic to many marine organisms and since the powder eventually settled on the ocean floor, bottom dwellers would have been extremely susceptible to this pollution. Organisms not directly affected by the copper might be affected by the loss of a food source which was poisoned by the heavy metal.
Career Focus: Oceanography
Making Sense O
f It All
Career Focus: Oceanography Oceanography (or Marine Science) is the scientific study of the physical and biological components of the Earth's oceans. This field of study draws on several disciplines, integrating biology, geology, physics, chemistry, and engineering as they relate to understanding the ocean.
Marine Biology, one of the main branches of oceanography, involves the study of ocean plants and animals and the interrelationships between them and their environment. Marine biologists may also focus on the effects of pollution and human intervention on the organisms living in the ocean. Marine Geologists map the ocean floor, study shoreline problems, examine plate tectonics and seafloor spreading, and analyze characteristics of seafloor sediments. Physical Oceanographers study wave dynamics, tides and currents, ocean/atmosphere interactions, water density, temperature, and underwater acoustics and sound transmission.
Chemical Oceanographers are concerned with the chemistry of seawater, its major salts, and its many trace elements. These scientists also study the ocean's dissolved solids and gasses and the relationships of these conditions to the geology and biology of the ocean as a whole. Marine Engineers design and build oil platforms, ships, harbors, and other structures Students interested in an oceanography career typically enroll in a variety of science and math classes in college, including biology, chemistry, physics and geology. Although all marine scientists specialize in one area of research, they must also be familiar with other marine science disciplines to appreciate and make connections between them. Marine science contributes to our awareness and appreciation of the interconnection of all natural environments.
