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Being involved in the Species Distribution Project means you will be a member of a scientific research team. When doing research, it is essential to keep accurate records about your work. This information should all be kept together in a lab notebook. You will find this very helpful when you need to describe to others what you have done. Your lab notebook should include a description of all procedures performed, any deviations or errors that may have occured, and documentation of all observations and data collected during your research.

Sampling in Field

In order to obtain live specimens of tardigrades you will need to go into the field and collect samples from various locations. Record the date, time, and location, including type of tree, for each sample you collect. The greater the variety of locations you take your samples from the higher the potential for different types of water bears. Collect samples of moss and lichens from tress and rooftops, being carefully not to harm any of the vegetation (Please use extreme caution when collecting from high places.) Place the samples in separate paper sacs, making sure to label each sac with the appropriate collection data. These can then be stored in a dry place for an unlimited amount of time. 

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Rehydration and Extraction

After returning to the lab, the animals can be rehydrated and isolated from other debris. Being careful not to mix samples, place each half of each sample (saving the other half) in a separate dish and add enough water to cover all of the collected material. (The water should be spring water or tap water that has been in an open dish for 24 hours, allowing for evaporation of the chlorine.) The sample should soak for at least 3 hours and up to 24 hours. After the animals have been rehydrated, they can be seen by examining a small portion of the debris under a dissecting microscope. Isolate the tardigrades by placing them in a small culture dish with water, a very small amount of debris, and food (rotifers and nematodes which can be found in your original sample).

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Water bears can be maintained in a culture dish for a number of weeks. Maintaining a few key elements will provide an appropriate habitat for tardigrades. First they must have enough water to adequately cover them. Every 3-5 days most of the water should be taken out and clean water should be added. The other key element is providing them with enough food. Add rotifers and nematodes as the are eaten. Also keeping a loose cover over the dish helps keep unwanted debris out and helps slow evaporation.

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LM/SEM Microscopy Preparation

Once you have isolated a number of tardigrades you will want to take a closer look at them under a compound light microscope (LM). First they must be slowed down. Placing them in anoxybiosis, a death like state when no oxygen is present, is the best way to do this. Put a number of tardigrades into a small vial, fill the vial with water, and then seal it. After a few hours your animals should be in "dead man's float", a temporary state. They will appear bloated and motionless. A specimen can then be placed on a slide and covered with a cover slip. You will want to use Vaseline or a similar substance on the corners of the cover slip to keep from squishing the animal. Now examine the animal and make a detailed drawing. When you are finished the animal can be returned to a culture dish, where it will return to its original state.

You are know ready to identify your water bear on the web. Click here to access the Taxonomic Key.

Protocol for preparation using a scanning electron microscope (SEM) are stilled being refined. If you have access to an SEM please contact us and we will provide you with further instruction.

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Mailing Samples

If you have found a sample you would like to mail to us here are a few guidelines.

Packaging - place at least two handfuls of your sample in a labeled paper bag. It can then be mailed in a padded envelope or small box. Include a short letter indicated what species you have and why. Send package second day mail.

Address to:
SDP Dr. Susie Balser
Dept. of Biology
Illinois Wesleyan University
PO Box 2900
Bloomington, IL 61702-2900

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Website Authors: Karen Lindahl and Professor Susie Balser in affiliation
with Illinois Wesleyan University. Last revised 1 Oct. 1999.