Sampling Method 3 - Modified Hand Sorting

The Modified Hand Sorting sampling method is used to determine the population and species diversity of earthworms in a specific volume. With this method, you can study what species of earthworms live and work at different depths in the soil.

The purpose of this sampling method is to locate as many earthworms and earthworm cocoons as possible at one or two different soil depths. You will count all of the worms and then use the Key to Reproductively Mature Earthworms Found in Canada to determine the scientific name of the adult earthworms in your sample. Once you have identified the adults, use the Earthworm Field Guide to learn more about each worm in your sample. Don't forget to use the online database to submit your data to Worm Watch.

Earthworms live moist cool soil almost anywhere. They can also be found in many different habitats including: in, under rocks, aged dung pats, around water ways, with piles of dead leaves, under the moist bark of dead or fallen trees, and in your lawn or garden. To find these earthworms you will need to flip over rocks, logs and other bits of deadfall, and strip back the bark of the soil-side of fallen logs. Even if you don't find a worm you may be able to see evidence that earthworms are living in the soil. Look for piles of earthworm cast material (fancy words for earthworm poop) on the surface of the soil and tunnel or burrow entrances and exits.

There are highly productive soils around the World where earthworms do not exist, possibly because of glaciation, physical barriers to migration or for reasons that are yet unknown. You can help us understand more about earthworm habitats by recording your location, soils information, and all the other information asked for on the data sheet as accurately as possible.

1. Download and print a copy of the materials that you will need for Sampling Method 3: Modified Hand Sorting
2. Gather all of the equipment and check that you have everything before heading out to sample.
3. Make sure you have the following:
   • sampling template
   • Worm Watch site data sheets
   • Earthworm Size Chart
   • Earthworm Anatomy diagram
   • Key to Reproductively Mature Earthworms Found in Canada.
4. You may also want to have one copy of the Earthworm Field Guide with you as a reference.

Do not use a glass thermometer to measure the temperature of the soil. It could break and cut you.

Make sure you are in a safe location.

You are entering the homes of other living organisms. Treat these homes with dignity and respect. For example, if you turn over a rock replace it in exactly the same position as you found it when you are finished.

1. Select a site to sample. Remember to make sure you have permission to sample in this location.
2. When you have determined where you will sample, complete the first page of the Worm Watch Site Data sheet. This information is very important. Please be as detailed as possible. Use a pencil (pencil doesnŸt run when wet and also writes on damp paper) to complete all of the sections before you begin sampling.
3. Record your location as accurately as possible using distance and direction from road intersections, towns, cities or well known landmarks. You can also use GPS technology to determine your location.
4. Your teacher will give you more information such as the amount of time that you can sample and the boundaries of the sampling area.

1. Lay out the sampling template. This will ensure each group is sampling in the same amount of space.
2. Set your plastic sheets and containers just outside of your sampling area. The containers will be used to hold your earthworms until they have been counted.
3. Remove the surface debris (leaves, loose soil) from inside the sampling area and place it on the plastic sheets. Sort through this material carefully looking for earthworms and cocoons. Many earthworm cocoons look like kernels of popcorn. Place the earthworms and cocoons in one of the plastic food containers. Go to the Sorting section of this page and follow the instructions before digging.
4. Next, you are going to remove the first 10 cm of soil. Use the shovel to dig down approximately 10 cm deep. Remember to stay within your sampling area. Place this soil and plant material on your plastic sheet. Sort through this material carefully looking for earthworms and cocoons. Place the earthworms and cocoons in one of the plastic food containers. Go to the Sorting section of this page and follow the instructions before taking another sample.
5. Finally, you are going to dig down another 10 cm. Use the shovel to remove approximately another 10 cm of soil from your sampling area. Sort through this material carefully looking for earthworms and cocoons. Place the earthworms and cocoons in one of the plastic food containers. Go to the Sorting section of this page and follow the instructions.

It is time to sort your earthworms.

1. Place all of the adult earthworms into one plastic container. Remember, adult earthworms have a visible clitellum. Check the Earthworm Anatomy diagram if you do not remember where to find the clitellum.
2. Place all of the juvenile earthworms into a second plastic container. Juvenile earthworms are not ready to reproduce and do not have a clitellum.
3. Place all of the earthworm cocoons into a third plastic container.

Make sure you have your data sheet and pencil with you for this part of the activity.

1. Count the number of adult earthworms in the container. Record this information on your data sheet.
2. Count the number of juvenile earthworms in the container. Record this information on your data sheet.
3. Count the number of cocoons in the third container. Record this information on your data sheet.
4. Return the juvenile earthworms and cocoons to their original habitat. Make sure to put them back exactly where you found them or they might die. CAUTION: Do not return rocks immediate on top of earthworms, give the stressed earthworm a bit of time to recover and dig itself back into the soil.

1. Set up three plastic food containers. Label the first one "LARGE", the second "MEDIUM" and the third container "SMALL".
2. Use the plastic ruler and the Earthworm Size Chart to estimate the size of each adult earthworm. Do not pull on or stretch out the earthworm. All of your worms might be in the same size category or you could have a number of worms in each container.
   
   
   
   
   
   1. Place earthworms that are between 0 and 55 mm into the SMALL container.
   2. Place earthworms that are between 56 and 110 mm into the MEDIUM container.
   3. Place earthworms that are between 111 and 300 mm into the LARGE container.
3. As you discovered in Investigation #2, the next step in the key is determine the colour of your earthworm. Remember, if the specific colour is NOT listed, then use "Other Colour" parts of the Key.
4. Follow the steps in the Key to Reproductively Mature Earthworms Found in Canada to identify the earthworms in each container. If you are having trouble, go back to Investigation 2 - Identifying an Earthworm. This investigation walks you through the Key in a step-by-step fashion.

   Question? What if you cannot identify an earthworm using the Key? Put one or two representative adults into one of the containers and bring it back to school or home with you. Keep earthworms cover with moist or litter and keep them in the shade away from the sun. Then please follow the instructions under reporting to Worm Watch.

5. Complete the data sheet. Record the number of each species of earthworm that you find in the appropriate column. Four examples are provided on the data sheet. In the examples, Group #1 would have found:
   • 3 Allolobophora chlorotica
   • 6 Aporrectodea rosea
   • 2 Aporrectodea trapezoides
   • 4 Aporrectodea tuberculata
6. After they have been counted, it is very important to return the earthworms to the place that you found them. Always put some soil or litter on top of the earthworms. DO NOT LEAVE EARTHWORMS ON TOP OF THE SOIL, UNLESS THAT IS WHERE YOU FOUND THEM.
7. Make sure to collect all of your materials and garbage before leaving the site. Put everything back just the way you found it. People looking at the area should not be able to tell that you were there.

1. Use the Internet to access the Worm Watch web site and select the online database. Simply follow the instructions. This procedure allows you electronically transfer your data to Worm Watch.
2. If you are having trouble accessing the database, send an e-mail to Worm Watch describing the problem, and we will get back to you.
3. Worm Watch scientists are available to verify your earthworm identifications or try and identify earthworm species that are not listed on the taxonomic key. Please follow the procedure outlined below:
   • Select one representative adult of each earthworm species that you would like verified. If you found four different species, you will be sending four different adult earthworms.
   • Please make sure it is an adult earthworm with a fully developed clitellum.
   • Place each specimen in a separate container.
   • Add some wet bunched-up paper towels to a plastic container. The wet paper towels will serve as bedding and protect the earthworms during transport.
   • Place the worm in the container and poke a few air holes in the lid.
   • Label the container and secure the lid with packing tape.
     
     
     
     
     
     
     
     
     
     
     
   • Send the container(s) to Worm Watch at the address shown below.
   • Include a copy of your data sheet with the specimens.
   • Please use Priority Post, Express Post or courier to make sure the earthworms get to Lethbridge alive.

NOTE: Please send earthworms at the beginning of a week and not on a Friday to minimise the possibility that the earthworms will be stored for a long period of time in too hot or too cold conditions.

NOTE: Earthworms can survive for approximately one week if kept in a container with wet paper towels in a cool dark or shady place.

• Remove the earthworm and the soil from the container you brought from the field
• Place the earthworm into a clean small screw top PLASTIC container. For example, clean sample-size shampoo bottles work well. Do not use any flip top containers because they will leak!
• Fill the vial with about 20 ml of colourless drinking alcohol (vodka, white rum, and tequila are preferred), 70% ethanol, or methylated spirits. Beer, wine, and rubbing alcohol are not acceptable for preservation.
• CAUTION: Children and students should be supervised by an adult or the teacher while handling these liquids!
• Gently drop the earthworm into a labeled vial and close the lid firmly. Clearly indicate on the label what kind of liquid is in the bottle! Unmarked vials will be discarded.
• Once the earthworm stops moving (about 1 minute), open the vial, and tightly fill the vial or container with cotton balls to the top.
• Add enough liquid so that the cotton is completely saturated and there is a very small amount of excess liquid on top of the cotton balls. It is important that there is a sufficient amount of liquid preservative in the vial so that the earthworm remains in contact with the liquid at all times during shipping.
• HINT: pack the earthworm with the cotton ball do not squish the earthworm onto the bottom in a heap with the cotton balls. The cotton balls are there to ensure your specimen does not get beaten up, and stays preserved during its journey to the Worm Watch lab.
• Firmly secure the lid and place the vial into a plastic bag.

• Make sure that there is enough liquid preservative in the vial and that the lid is on tight so nothing can leak out of the container.
• Label the screw-top container the name of the earthworm species or unknown (unknown #1, #2, etc.), where you found it, and your name and email address or telephone number. You can include your original data sheet if you like.
• Place your vial inside another Ziplock bag. We recommend the freezer Ziplock bags because they are made out of a thicker plastic. Remove the air and seal the bag.

We want your earthworms in good condition so we can identify them. After all you may have found a new species!

All your containers should be labeled with your name, what is inside the container, and where you collected the worm.

• Tightly package your containers in newsprint, or other packing material like Styrofoam popcorn or popcorn inside a small box or sturdy envelope. Then the containers will not shift around during transport to the lab.
• Please include a data sheet or a piece of paper with your name, address and email address or phone number so we can contact you later.
• Label the package with the Worm Watch address on page your return address, and apply sufficient postage to the package. Worm Watch will not accept packages C.O.D..
• Please send your live earthworms Monday - Thursday to avoid specimens being stored in either extreme cold or hot for extended periods of time. Preserved specimens are also best sent on a weekday.