unit 3 investigate and archive: limpets sandy beach ... · the limpets curriculum is aligned with...

Greater Farallones National Marine Sanctuary

Monterey Bay National Marine Sanctuary

Channel Islands National Marine Sanctuary

Farallones Marine Sanctuary Association

Pacific Grove Museum of Natural History

Unit 3 Investigate and Archive: LiMPETS Sandy Beach Monitoring and Data Entry

3RD EDITION

LiMPETS Sandy Beach Monitoring Program: Curriculum Guide

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LiMPETS Curriculum

The LiMPETS curriculum was created by the Farallones Marine Sanctuary Association and updated by the Pacific

Grove Museum of Natural History in partnership with many generous individuals and organizations. We would like

to thank everyone for their countless and valuable contributions to this project.

Funders

The Greater Farallones National Marine Sanctuary supported the development of the LiMPETS Sandy Beach Monitoring Program through the T/V Puerto Rican Restoration Fund.

NOAA B-WET (Bay Watershed Education and Training Program) provided full support for the development, design, and update of this curriculum (2009–2011, 2014).

Curriculum Development and Editing

Gillian Ashenfelter, Lick-Wilmerding High School

Cynthia Cudaback, Ocean Consulting

Amy Dean (editor), Farallones Marine Sanctuary Association

Dr. Jennifer Saltzman, Farallones Marine Sanctuary Association

Tammie Visintainer, University of California, Berkeley

Alison Young, Farallones Marine Sanctuary Association

Ann Wasser, Pacific Grove Museum of Natural History

Emily Gottlieb, Pacific Grove Museum of Natural History

Maps, Illustrations and Design

Illustrations: Jamie Hall and Vanessa Gusman

Maps: Tim Reed, Greater Farallones National Marine Sanctuary

Design: Annabelle Ison, Ison Design

TABLE OF CONTENTS

Unit 3 | Investigate and Archive: LiMPETS Sandy Beach Monitoring and Data Entry

Using the LiMPETS Curriculum 2

Next Generation Science Standards, Common Core Standards, and Ocean Literacy Principles 3

FOR TEACHERS: Planning and Monitoring Day Tips 5

ACTIVITY: LiMPETS Sandy Beach Monitoring 6

ACTIVITY: Data Entry 8

ACTIVITY: Optional Extension to Monitoring — Acanthocephalan Investigation 9

Acanthocephalan Parasite Fact Sheet ............................................................................................................................11

Dissection Guide ........................................................................................................................................................................12

Acanthocephalan Data Sheet ............................................................................................................................................14

Acanthocephalan Data Analysis Worksheet ...............................................................................................................15

ACTIVITY: Acanthocephalan Parasite Life Cycle Game 16

Student Handout and Worksheet .....................................................................................................................................17

Playing Cards ................................................................................................................................................................................19

2 • LiMPETS Sandy Beach Monitoring Program: Curriculum Guide

Using the LiMPETS Curriculum

The LiMPETS curriculum was designed for a broad range of participants; middle school and high school students, college undergraduates, environmental education organizations, and community groups. We encourage you to adapt and customize this curriculum to suit the needs of your unique class or group. However, there are some essential elements that are required in order to participate. At minimum, teachers or group leaders should set aside three days to conduct the essential elements of the program: one day for classroom preparation, one day for monitoring, and one day for data entry and assessment.

The following outlines both the required and optional elements of this curriculum:

Unit 1: Getting Started (required reading for teachers and group leaders)

Unit 2: Engage and Prepare: In-class Introductory Activities for Sandy Beach Monitoring

ACTIVITY: The Essentials of LiMPETS In-class Preparation (required)

ACTIVITY: Monitoring Mole Crabs in the Classroom (suggested)

ACTIVITY: Investigating the “Crab” in Mole Crabs (optional)

ACTIVITY: Sandy Beach Food Chain, Trophic Levels, and Biomagnification Game (optional)

ASSESSMENT: Student Pre- and Post-Monitoring Reflection (optional)

Unit 3: Investigate and Archive: LiMPETS Sandy Beach Monitoring and Data Entry

ACTIVITY: LiMPETS Sandy Beach Monitoring (required)

ACTIVITY: Data Entry (required)

ACTIVITY: Extension to Monitoring — Acanthocephalan Parasite Investigation (optional)

Unit 4: Analyze and Interpret: Data Analysis Activities for the Classroom (optional)

ACTIVITY: Visualizing Data from a Great Day at the Beach

ACTIVITY: Exploring Trends in Mole Crab Abundance Over Time

Unit 5: Communicate: Effectively Communicating Science and Taking Action In Your Community (optional)

ACTIVITY: Student Pre- and Post-Monitoring Reflection

ACTIVITY: Communicating Science Through Posters and Oral Presentations

ACTIVITY: Taking Personal Action to Protect the Ocean — Us Vs Them

The LiMPETS curriculum is aligned with the Next Generation Science Standards and Common Core Standards for grades 6–12. It is also aligned with the Ocean Literacy Principles and Concepts, which identifies the content knowledge that an ocean literate person should know by the end of 12th grade, www.oceanliteracy.org.

http://www.oceanliteracy.org

LiMPETS Sandy Beach Monitoring Program: Curriculum Guide • 3

Middle School Curriculum AlignmentActivity Next Generation Science

Standards Common Core Standards Ocean Literacy Principle

LiMPETS Sandy Beach Monitoring

Practices

planning and carrying out investigations

Core Ideas

LS2.A: interdependent rela-tionships in ecosystems

Crosscutting Concepts

patterns

RST 3: follow precisely a multistep procedure when carrying out experiments, taking measurements, or performing technical tasks

2.D: sand is redistributed by waves and coastal currents seasonally

5.H: tides and waves cause zonation patterns along the shore

5.D: ocean biology provides unique examples of adapta-tions and relationships

Acanthocephalon Parasite Investigation

Practices


Core Ideas

LS2.A: interdependent rela-tionships in ecosystemsLS4.B: natural selectionLS4.C: adaptation Crosscutting Concepts

structure and function

RST 3: follow precisely a multistep procedure when carrying out experiments, taking measurements, or performing technical tasks.

5.C: some major groups are found only in the ocean


Acanthocephalon Life Cycle Game

Practices

developing and using models

Core Ideas

LS2.A: interdependent rela-tionships in ecosystemsLS2.B:cycle of matter and energy transfer in ecosys-tems LS4.B: natural selectionLS4.C: adaptation Crosscutting Concepts

energy and matter




High School Curriculum AlignmentActivity Next Generation Science

Standards Common Core Standards Ocean Literacy Principle

LiMPETS Sandy Beach Monitoring

Practices


Core Ideas

LS2.A: interdependent rela-tionships in ecosystems

Crosscutting Concepts

patterns


2.D: sand is redistributed by waves and coastal currents seasonally

5.H: tides and waves cause zonation patterns along the shore


Acanthocephalon Parasite Investigation

Practices


Core Ideas

LS4.B: natural selectionLS4.C: adaptation Crosscutting Concepts

structure and function




Acanthocephalon Life Cycle Game

Practices

developing and using models

Core Ideas

LS2.C: ecosystem dynamics, functioning, and resil-ience LS4.B: natural selection LS4.C: adaptation Crosscutting Concepts

energy and matter




ACTIVITYFOR TEACHERS

Planning & Monitoring Day Tips

LIMPETS WEB RESOURCES:

• Sandy Beach Methods, http://limpets.org/sb_methods.php

• Sandy Beach Equipment, http://limpets.org/sb_equip.php

• Sandy Beach Datasheets and Forms, http://limpets.org/sb_data.php

• Sandy Beach Monitoring Sites, http://limpets.org/sb_sites.php

BEFORE YOU GO:

• Check the tides: Plan to monitor when the tide is fairly low, ideally during the ebbing tide, when tide height is about 3 feet or lower. For tide predictions online, visit http://tidesandcurrents.noaa.gov.

• Consider your group size: Monitoring works best with a group of 25 students or less. If there are more students in your class, you may also establish another 50 m sampling area that is at least 50 m from the first; however, you will need two sets of equipment. Alternatively, you may choose to have half the class involved in another activity on the beach.

• Talk to your local LiMPETS Coordinator: Let he/she know your plans, equipment needs and monitoring date(s). If possible, he or she will assist you in the field.

• Determine equipment needs: Make copies of the data sheets and forms on the LiMPETS website and gather all necessary equipment.

• Review and prepare students: Review the monitoring methods and prepare your students using the activities in Unit 2. Student in-class preparation is a required element of the LiMPETS program.

• Site Details: Are there bathrooms at your monitoring site? How do you get there and where should you park? LiMPETS site information is on the website.

• Check the marine forecast: If there is a high surf advisory, cancel your trip or modify your plans.

AT THE BEACH:

• Safety check: Once you arrive at the site, check the surf conditions. Does the swash zone appear dangerous? If so, do not monitor. Remind students of safety considerations while monitoring.

• Clothes, gear, and electronics: Gear should be stowed safely, far above the swash zone. Students should prepare to get wet up to their knees: take off shoes and socks, remove electronics from pockets, etc.

• Divide students into 5 monitoring teams of 3 – 5 students per team, ideally. Students can divvy up jobs as desired; however, one student must be responsible for recording the data, making certain that all data sheets are filled out completely and accurately.

• Students should complete the Field Log and the top portion of their data sheets before they begin.

• Monitoring Tips: Take cores quickly, after the waves recede. Avoid walking directly along the transect.Never leave any equipment unattended in the swash zone.

• Before you leave the site, be sure that all data sheets are filled out properly – names, date, start and end time, etc.

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http://limpets.org/sb_methods.php

http://limpets.org/sb_equip.php

http://limpets.org/sb_data.php

http://limpets.org/sb_sites.php

http://tidesandcurrents.noaa.gov


STUDENT HANDOUT ACTIVITY

LiMPETS Sandy Beach Monitoring OBJECTIVES:

• To connect teachers, students, and the community to the ocean, involve them directly in a real scientific endeavor, and increase their awareness of, and interest in, the marine environment.

• To establish baseline information about the abundance and distribution of the Pacific mole crab for California’s national marine sanctuaries.

ACTIVITY TIME: 75–120 minutes

GRADE LEVEL: 6–college



• Sandy Beach Equipment, http://limpets.org/sb_equip.php

• Sandy Beach Datasheets and Forms, http://limpets.org/sb_data.php

BACKGROUND: Your students should be familiar with the how, what and why of monitoring before they go to the beach. Preparation is both key to quality data collection and to an exciting and meaningful student experience. Classroom preparation activities and sandy beach ecology background can be found in Unit 2.

PROCEDURE: The sampling methods for LiMPETS Sandy Beach Monitoring are described below:

• Setting up the sample area: A 50-m line is placed above the swash zone, parallel to shore. This line should be placed in the same location each time the beach is surveyed. A GPS or compass can be used to find this location.

• Complete the Field Log.

• Using the Random Number Table, choose five random numbers between 0 and 50. These numbers should be at least 5 meters apart.

• Locate these positions along the 50-m line and stretch

a 10-m transect, perpendicular to the 50-m line, into the swash zone. If the swash zone is wide and it is safe to do so, the 10-m transect should start at the top of the swash zone. If the swash zone is narrow, the 10-m transect should start five meters above the top of the swash zone. A flag should be placed securely in the sand every meter along the transect.

• Collecting a sample: One sample should be collected at each of the 10 flags along the transect. To collect a sample, wait until the waves have receded. Quickly press a core 10 cm into the sand at or next to one flag. Some sites within the Monterey Bay and Channel Island areas collect cores 20 cm in depth. Check with your LiMPETS coordinator if you are unsure about what depth to take cores. Tilt the core diagonally, lift, and use one hand to hold the sand in place. Place the sample into sieves and pour water overtop to wash the sand away.

• Recording the data: If mole crabs are present in a sample, determine the size and sex of each crab. Determine the size by measuring the length of the carapace with a caliper (to the nearest millimeter). Determine sex by carefully lifting the telson. Females are identified by the presence of modified legs, or pleopods, under the telson. Ovigerous females are

Dry Beach

Survey Area – 50 meters 0 m 50 m

Sw

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one

Sample 1

Sample 10

TRANSECT #1 #2

Ocean

#3 #5#4

Schematic of sample area showing 5 randomly placed transects stretching through the swash zone. Transects are 10 meters in length.


http://limpets.org/sb_equip.php

http://limpets.org/sb_data.php


ACTIVITYACTIVITY

identified by an orange mass of eggs. Males lack both pleopods and eggs. Sex cannot be determined if crabs are less than 10 mm, but size should still be recorded.These tiny crabs are considered “recruits.” Record data on data sheet and return animals to the water in the exact location they were collected from.

• Data sheet check: When all 5 transects have been completed, check to make sure the data sheets are filled out properly – names, date, start and end time, etc. Also, remind students that zero is a number too! For example, if students do not find any mole crabs, they must check the ‘zero’ box on their data sheet.

EXTENSION ACTIVITY:

• Parasite Analysis: In this optional extension to LiMPETS Sandy Beach Monitoring, the presence of a parasitic worm (phlyum Acanthocephala) is investigated. A fishing permit or scientific collecting permit is needed to conduct this activity.

• If you plan to conduct the parasite analysis, here’s what you need to do while at the beach. Collect about 30 adult crabs for the in-class dissection (> 9 mm). Do not collect ogiverous females. If you cannot find 30 crabs, that’s ok. Collect as many as you can find. Placed in a ziplock bag and put in a freezer for more than 4 hours. This optional activity is described in detail on page 8.

ASSESSMENT:

After students have completed their monitoring activities at the beach, ask them to complete the Student Reflection, post-trip reflections questions at the end of Unit 2.

Female sand crabs are identified by the presence of modified legs, or pleopods, located under the telson.

FMSA


ACTIVITY

Data EntryOBJECTIVE: Students will archive their data in the LiMPETS database and will understand why long-term cumulative data are important.




• Data Entry and Results, http://limpetsmonitoring.org/data_entry.php

MATERIALS:

• Computer(s) or computer lab

• Access to the web

• Data sheets

• Username and password

BACKGROUND: Unglamorous as it may seem, data entry and analysis are extremely important parts of the process of science. Entering LiMPETS data into one database ensures that everything is stored in one place and is available for long-term comparisons and other types of analyses.

Entering data is your responsibility. Whether you choose to enter data yourself or make data entry part of the student experience, all LiMPETS participants are required to enter their data at http://limpets.org.

PROCEDURE:

• It is best to enter data soon after monitoring so that it is fresh in your mind(s).

• If you are new to the LiMPETS program, you will need a username and password to access the database. Contact your LiMPETS coordinator and he/she can set this up for you.

• Review all data sheets before you begin. Make sure that data sheets are filled out completely and accurately. If data is missing or there are obvious errors, contact your LiMPETS coordinator to discuss whether you should enter your data.

• Options for data entry include: teacher enters data,

one student or group of students enters all data, or each group of students enters their data separately.

• If you choose the last option above, you must login into the database first to input the date and location of your monitoring event. See Step 1 below.

STEP 1 – CREATE A NEW MONITORING EVENT

• Go to LiMPETS website > click on Data Entry and Results > click on Sandy Beach Data Entry.

• Enter your username and password > click Login.

• Click Add a New Sandy Beach Monitoring Event.

• Enter the required information > click Save.

• In the ‘data sheet label’ field, create a label that identifies your unique survey. If you completed two transects in one day, create a label that identifies between the two transects (e.g. SunsetSouth_Jun10 , GalileoHS_Spr2010.)

STEP 2 – FIELD LOG

• Continue from Step 1 above > click Add the Field Log > enter the required information > click Save.

• If students are entering data, they will first need to login and select the ‘monitoring event’ showing the correct date and location.

STEP 3 – ENTER SAND CRAB DATA

• Navigate to page titled Data Entry Step 2 using the bar along the top of the page, if necessay.

• Complete data sheets for transects 1-5.

• If zero crabs were found in any sample, be sure to check the ‘Zero Crabs Found’ box just below the sample number.

• Click Save > check accuracy of data for each transect > click Confirm.

• Exit data entry section when finished and log out.

STEP 4 – MAIL US DATA SHEETS

• It is important that you send copies of data sheets to your local LiMPETS coordinator via mail, fax or email.

http://limpets.org


ACTIVITY

Optional Extension to Sandy Beach Monitoring – Acanthocephalan Investigation

OBJECTIVE: Students will investigate the presence of parasites in Pacific mole crabs. Students will learn about the life cycle of a parasite and how it influences organisms in a food web. They will examine the anatomy of mole crabs while using dissection techniques and scientific equipment.




• Acanthoceophalan Parasites, http://limpets.org/sb_acantho.php


BACKGROUND: This activity is an optional extension to the LiMPETS Sandy Beach Program. In order to conduct this activity, you will need to collect the adult mole crabs that you find at the beach and freeze the crabs overnight.

Important: Because you will collect and dissect mole crabs for this activity, you must either have a LiMPETS coordinator with you at the beach while you collect mole crabs or a fishing license from the California Department of Fish and Game. A one-day recreational fishing permit costs about $15. For online purchase, go to https://www.calicensetofish.com. Questions? Call the California Department of Fish and Game License and Revenue Branch at: (916) 928-5805.

Acanthocephalans (spiny-headed worms) are parasites that require two hosts: as juveniles they live in either crustaceans or insects, and they develop into adults in the digestive tracts of vertebrates. In this case, these parasites use Pacific mole crabs as their primary intermediate host and live inside a part of the crab called the posterior hemocoel (near the midgut). Surf Scoters (diving ducks) are the definitive host for acanthocephalans, but the parasite affects sea otters as well. Acanthocephalans have caused Surf Scoter die-

offs and disease in sea otters by causing peritonitis, an inflammation of the abdominal cavity.

MATERIALS: The following materials are required for each lab table or group of students

• Acanthocephalan Parasites: Fact Sheet

• Student Dissection Guide and Data Sheet

• Student Worksheet: Data Analysis (optional)

• Microscope, dissecting scope, or magnifying glass

• 2 Petri dishes: 1 for crabs and 1 for parasites

• Large waste bowl or 100 ml beaker

• Squirt water bottle filled with fresh water

• Small scissors

• 2 Tweezers or forceps

• Caliper

• Gloves (optional)

FMSA

http://limpets.org/sb_acantho.php


https://www.calicensetofish.com



ACTIVITY

PROCEDURE – BEFORE THE DISSECTION

• During your monitoring trip to the beach, randomly collect about 30 adult crabs for dissection (> 9 mm). Do not collect ogiverous females. If you cannot find 30 crabs, that’s ok. Collect as many as you can find.

• Place the crabs in a zip lock bag and store them in a freezer for more than 4 hours. Make sure to note the date and beach where the crabs were collected.

• You MUST have a valid fishing license from the California Department of Fish and Game in order to collect crabs legally. A one-day recreational fishing permit costs about $15. For online purchase, go to https://www.calicensetofish.com.

• Assign students readings, Acanthocephalan Parasites: Fact Sheet and Dissection Guide, for homework (or in-class) prior to the activity.

• You may optionally conduct the game on page 15 of this unit to help prepare your students.

PROCEDURE – THE DISSECTION

• Take crabs out of freezer approximately 30 – 60 minutes before the dissection.

• Each group of students will need thawed crabs and a complete set of materials before they begin.

• One student in each group should record their data on the Acanthocephalan Data Sheet.

• Dissection procedures and photos are included on the Dissection Guide.

• Students should be sure to measure their crabs with calipers BEFORE beginning their dissection.

• You can see the parasites with the naked eye, but using a microscope or magnifying glass will make the identification of the parasites easier.

• When finished, ask each group of students to record their data on a white board or chalkboard in the classroom. All students should have a complete copy of the data from the entire class.

• Clean-up: Have the students place all the crab parts in their large waste bowl, then dispose of all the dead material in a trash can.

PROCEDURE – DATA ENTRY

• Go to LiMPETS website > click on Data Entry and Results > click on Sandy Beach Data Entry.

• Enter your username and password > click Login.

• Select the ‘monitoring event’ showing the correct date and location. If you have not yet created a ‘monitoring event’ that shows the date and beach that you monitored, please do this now. Instructions are described in the previous “Data Entry” activity.

• Click Add the Parasite Datasheet at the bottom of the page > enter the required information > click Save.

• Check to make sure that data has been transferred accurately > click Confirm.

EXTENSION ACTIVITIES:

• You may ask students to visit the LiMPETS website, http://limpets.org, to review the “Species Monitored” pages and conduct additional web research on Acanthocephalan parasites.

ASSESSMENT: Students complete the Dissection Guide and Data Analysis Worksheet in this section.

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http://limpets.org


STUDENT HANDOUT

Acanthocephalan Parasites: Fact Sheet

A parasite is an organism that lives in or on a host (another

animal or plant) and usually causes harm to its host organism.

Nearly all animals have parasites and they are therefore

an important part of ecosystems. There are many different

types of parasites, including parasitic worms. Members of

the phylum Acanthocephala are known as “spiny-headed

worms” and are characterized by the presence of an

evertable proboscis (a feeding or sucking organ), armed with

spines. These parasites have complex life cycles that require

multiple hosts. As juveniles, they live in crustaceans such

as sand crabs. As adults, they live in the digestive tracts of

vertebrates such as sea otters or birds.

Life Cycle

In the ocean, acanthocephalan eggs float freely in the water until they are accidentally ingested by suitable intermediate host. The acanthocephalan Profilicollis altmani uses Pacific mole crabs (Emerita analoga in California) and spiny mole crabs (Blepharipoda occidentalis) as intermediate hosts. Once these crabs eat an acanthocephalan egg, the eggs develop into a juvenile parasite, called a cystacanth. The definitive host is infected when it ingests an infected mole crab. Various coastal birds are a definitive host for this acanthocephalan, meaning that the parasite develops into an adult and can reproduce. The cystacanth excysts (emerges from its cyst) in the small intestine and matures into an adult worm. Eggs are then produced by the adult acanthocephalans and pass out of the bird in the bird’s feces back into the ocean to continue the cycle. Seabirds that are infected by this acanthocephalan include gulls, Willets, Sanderlings and sea ducks such as Surf Scoters and Common Goldeneye. The parasites affect California sea otters as well, but they are a dead-end host because the parasites are not able to reproduce.

Effects on Organisms

Pacific mole crabs are the primary intermediate host for acanthocephalans. In mole crabs, the parasites are located in the posterior hemocoel near the midgut. This parasite is prevalent in mole crabs with many of the largest mole crabs being infected. The parasites are not lethal to mole crabs, although they could affect their behavior, perhaps making them easier prey to fish and birds. In both the definitive and dead-end hosts, Acanthocephalans induce peritonitis, which is inflammation around the abdominal cavity. Peritonitis occurs when larval Acanthocephalan parasites that reside in the intestine migrate through the intestinal wall, allowing bacteria to infect the abdominal cavity.

Acanthocephalan peritonitis can cause death in its final hosts. It is currently estimated that 13-16% of deaths in the threatened California sea otter population have been caused by infection with this parasite. In addition, unusually high loads of acanthocephalan parasites have been linked to episodic deaths of thousands of Surf Scoters. Monitoring helps us to understand the life cycle, seasonal cycles, and prevalence of the parasites in populations of mole crabs and can lead to a better understanding of the prevalence of infection in otters and sea birds.

Definitive Host

Primary Intermediate Host

Dead End Host

Feces and eggs

Parasite egg


STUDENT HANDOUT

Dissection Guide for Acanthocephalan ParasitesPROCEDURE: Refer to the Photo Guide for photos of each of the steps below.

1. Measure the carapace length and determine the gender of the crab. Record this information on the data sheet.

2. With the scissors, cut off the posterior end of the crab, slightly back from the end of the carapace (a little bit more than the telson).

3. Cut the crab’s carapace up the middle and pry the two sides open with your fingers or tweezers.

4. Put the crab in a petri dish and place the petri dish under a microscope or dissecting scope, if you have one. Look at the midgut.

5. You are looking for small white “footballs” that are right under the carapace. You might have to dig around in the gut a little with the tweezers, but if there are parasites they are pretty evident. Flushing the inside of the crab with water using the squirt bottle can help find parasites. Make sure you keep pulling out the insides of the crab to thoroughly check the whole gut area for parasites.

6. Remove the parasite(s) and place them in a petri dish filled with fresh water. The parasite will excyst after a few minutes. Look at the parasite under the microscope. You should see spines around the head!

7. Record the number of parasites found in each crab on the data sheet. If your crab does not have any parasites, remember to record “zero” on your data sheet.

VOCABULARY

Parasite

Proboscis

Definitive host

Dead-end host

Hemocoel

Peritonitis

DISSECTION PHOTO GUIDE

1. RECORD SIZE AND GENDER. 2. CUT OFF TELSON; CUT CARAPACE UP

CENTER.

3. PULL APART THE SIDES OF THE CARAPACE. 4. LOOK FOR PARASITES.

5. FLUSH AND PROBE WITH FORCEPS TO

LOCATE ALL PARASITES IN MIDGUT.

6 & 7. REMOVE ALL PARASITES; RECORD TOTAL

NUMBER FOUND; PLACE IN PETRI DISH WITH

FRESH WATER.

gg


STUDENT WORKSHEET

Acanthocephalan Data Sheet

Name(s)

Crab Number Gender (M, F, FE) Size (mm) Number of Parasites

QUESTIONS:

1. What percentage of crabs collected from your beach are infected with parasites?

2. What percentage of males are infected? Females? Females with eggs?

3. On average, how many parasites were found in each infected crab?

3. At an urban beach in San Francisco, approximately 50% of all crabs are infected with parasites and an average of 2 parasites are found in every infected crab. How does this compare with your data?


STUDENT WORKSHEET

Acanthocephalan Data AnalysisName

DIRECTIONS:

1. Transfer your data into the following table. If your class dissected 3 crabs that were between 15 and 19 mm in length, and one parasite was found in each of these crabs, you would write a “1” in the three boxes below the “15-19 mm” column. Average these numbers in the last box in the column.

2. Using the data in the table, create a bar graph in the space provided. Don’t forget a graph title and labels for the axes. Is there any relationship between crab length and parasite infection? Explain.

10–14 mm 15–19 mm 20–24 mm 25–29 mm 30–34 mm 35–39 mm

Number of parasites per crab

Average number of parasites

GRAPH TITLE:


ACTIVITY

Acanthocephalan Parasite Life Cycle GameAuthor: Gillian Ashenfelter

OBJECTIVE: Students will understand the role that Pacific mole crabs play in the life cycle of the acanthocephalan parasite. Students will learn about intermediary host relationships and will consider the relationships between parasites and hosts.

ACTIVITY LENGTH: 30–45 minutes

GRADE LEVEL: 6–12

WEB RESOURCES:

• LiMPETS Species Monitored Pages, http://limpets.org/sb_species.php

BACKGROUND: See Acanthocephalan Parasites: Fact Sheet and the LiMPETS website for information. For the purpose of this game, you will assume that the metabolic rate of sea otters is higher than that of Surf Scoters, thus requiring more mole crabs as food. The parasite loads considered fatal in this game are not to be considered absolute representations, but are merely used to explain the concepts.

MATERIALS: The following materials are required for a class of 30 students, separated into 6 groups of 5 students each. Adjustments may be necessary, depending on class size.

• Cards for game play. Use different color paper, if available, to make 5 copies of the Surf Scoter page, 3 copies of the sea otter page, and 25 copies of the mole crab page.

• Use the same color paper to make 25 copies of the plankton page (without parasite eggs) and 15 copies of the plankton page (with parasite eggs).

• 5 dice

• 5 copies of student handout and worksheet

PROCEDURE AND GAME RULES:

• Cut up (or have students cut) each page so that you have plankton, mole crab, Surf Scoter and sea otter cards.

• Each group of 5 students should have the following: 1 die, a stack of 50 plankton cards (no parasites) and 10 plankton cards (with parasites) shuffled together, a stack of 20 additional plankton cards (with parasites), a stack of 50 mole crab cards, a stack of 10 Surf Scoter cards, a stack of 6 sea otter cards and one student worksheet.

• Divide the class into teams and hand out materials.

• Review the vocabulary listed at the beginning of the student handout with the students. Use the game cards to show them what plankton, mole crabs, Surf Scoters and sea otters look like.

• Go over the directions for the game together, outlined on the student handout.

ASSESSMENT:

• After playing the game, students can work with their team to answer the questions on the student worksheet. Discuss as a class.

ANSWER KEY:

1. The parasites were able to reproduce when infected crabs were ingested by a Surf Scoter, the definitive host.

2. An intermediate host is a host used by a parasite during the course of its life cycle but in which it is not able to reproduce.

3. Answers will vary. Acanthocephalans have co-evolved with their hosts. Natural selection favors characteristics that increase the passing on of the genes and reproductive success of the population. Therefore, parasites that cause death to their hosts may not be advantageous to their overall reproductive success.

4. Parasite egg > mole crab > Surf Scoter > parasite eggs released back into the ocean when the bird defecates.

http://limpets.org/sb_species.php


STUDENT HANDOUT

Acanthocephalan Parasite Life Cycle GamePURPOSE: To have fun while learning the role that Pacific mole crabs play in the life cycle of a the acanthocephalan (spiny-headed) parasite.

VOCABULARY: Parasite, intermediate host, definitive host, plankton, Pacific mole crab, Surf Scoter, sea otter.

GAME MATERIALS:

• 1 die

• One stack of 50 plankton cards with no parasites shuffled together with 10 plankton cards with parasites. The stack of plankton cards should be face down.

• One stack of 50 mole crab cards.

• One stack of 10 Surf Scoter cards.

• One stack of 6 sea otter cards.

• One stack of 20 additional plankton cards with parasites. Set aside.

GAME RULES:

• To win: One student needs 2 Surf Scoters and 1 sea otter.

• Roll the die to see how many plankton cards you are allowed to select from the deck. During your turn you may trade plankton cards for mole crabs, or trade mole crabs for Surf Scoters or sea otters.

• 6 plankton cards can be traded for 1 mole crab card.

• 3 mole crabs can be traded for 1 Surf Scoter.

• 5 mole crabs can be traded for 1 sea otter. Note – sea otters have higher energy requirements than Surf Scoters.

• When cards are traded in, return these cards to the bottom of the original deck.

ADDITIONAL GAME DETAILS:

• Some plankton cards have parasite eggs on them. You can still use these cards for making trades; however, do not return these plankton cards to the original deck. Any plankton cards with parasite eggs must stay with your new mole crab card (keep the crab card on top of any parasite cards). When you trade in mole crabs for a Surf Scoter, any parasite cards must remain with new Surf Scoter card.

• Parasites can reproduce inside of Surf Scoters. If a player earns a Surf Scoter card that is infected with one or more parasites, shuffle 5 more plankton cards with parasites into the plankton stack for every parasite the bird has accumulated.

• If a Surf Scoter has more than 10 parasites, it will die from swelling and irritation of the abdominal cavity. If a sea otter has more than 5 parasites, it will die. Note – this data is simplified. Studies indicate that Surf Scoters may perish after accumulating 700+ parasites, and sea otters may perish with 350+ parasites.

• If you have a mole crab with parasites, you may ‘feed’ your mole crab to someone else’s Surf Scoter, perhaps causing it to perish. You can also choose, during your turn, to feed your mole crab(s) to someone else’s sea otter. If you choose to do this you lose your mole crab card and cannot use it to trade in. Cards go back in the main stack.

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STUDENT WORKSHEET

Acanthocephalan Parasite Life Cycle Game

Name

1. When were the parasites able to complete their life cycle and reproduce?

2. Mole crabs are an intermediate host for acanthocephalan worms. Describe what you think that means based on the role mole crabs played in the game.

3. Think about how evolution and natural selection may influence the host-parasite relationship. Why do you think Surf Scoters are not killed by acanthocephalan parasites unless they have a very large amount of them?

4. Diagram the life cycle of the acanthocephalan worms:

PLANKTON CARDS: NO PARASITES

PLANKTON CARDS: PARASITES

PACIFIC MOLE CRAB CARDS

SURF SCOTER CARDS

SEA OT TER CARDS

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