The dissection of owl pellets can provide a valuable learning experience for students at all grade levels. The following guidelines will help to ensure that this activity is done in a safe fashion.
Use sterilized owl pellets, such as those sold by Carolina Biological Supply Company.
Owl pellets contain the remains of small animals that the owl has ingested and can be a source of bacterial contamination. Carolina’s individually wrapped owl pellets are heat sterilized at 250º F for 4 hours to eliminate harmful bacteria, including salmonella bacteria. Owl pellets from Carolina are not treat with chemicals. We recommend keeping the owl pellets wrapped and sealed in plastic bags until you are ready to use them. This will help prevent insect infestations or contamination.
Supervise dissection activities.
Oversee students’ owl pellet dissection activities to ensure they perform the activities safely.
Handle owl pellets, even sterilized ones, with good laboratory practices, as this affords another layer of safety.
This is good advice for any lab work involving biological materials. Learning good laboratory practices will serve students well throughout their academic careers and beyond.
Cover work surfaces
Covering laboratory or classroom tables with a disposable material such as absorbent pads or newsprint will aid in cleanup and is one more step to keep surfaces clean and safe. Also you can use disposable trays, paper plates, or paper as work surfaces for dissection of the pellets. Dispose of these upon completion of the activity.
No eating or drinking in the dissection area.
Like all lab activities, students should not be allowed to eat or drink during the dissection. Eating and drinking should take place before the activity or after the student has completed the activity and thoroughly washed his or her hands.
Personal protective equipment and hand washing.
As an added layer of protection, even when working with sterilized owl pellets, you may choose to have students wear disposable safety gloves during the activity. While it is not necessary, this provides an opportunity for students to learn the importance of personal protective equipment including how to properly use gloves. If using gloves, demonstrate how to avoid skin contact with the exterior of the glove during removal. The common practice is to:
- Remove the first glove by grasping the cuff, taking care not to touch bare skin, and peeling the glove off the hand so that the glove is inside out.
- Remove the second glove while holding the inside of the first in the ungloved hand.
- Drop both into the disposal receptacle.
Whether students use gloves or not, instruct them to keep their hands away from their faces, and to not touch other surfaces or items during the activity.
Immediately after the activity, have students thoroughly wash their hands with soap and warm water. Refer to the U.S. Centers for Disease Control and Prevention website for details (http://www.cdc.gov/cleanhands). A good antimicrobial foaming skin cleanser for use with water is BactoShield® by Steris. A waterless hand sanitizer can also be a very effective alternative if it is comprised of at least 70% alcohol. This can be used in addition to hand washing or, if soap and water are simply not available, in lieu of hand washing (though hand washing is preferable).
Note: Latex gloves can cause allergic reactions in some individuals. Carolina recommends nitrile disposable gloves.
Collect dissection supplies and sanitize work surfaces after the activity.
Allow students to use only the tools provided for the dissection. They should not use personal items that they will maintain in their possession after the activity. To minimize cleanup, use disposable dissection tools and then throw them away. Otherwise, sanitize the tools and work surfaces using an appropriate cleaning agent, such as 10% household bleach solution or 70% ethanol.
Owl pellet dissection is a safe and rewarding activity.
Through this investigation students learn about the food chain and the diets of owls. This activity also provides an opportunity to learn about safe laboratory practices and the importance of taking precautions. We want to reiterate that the owl pellets sold by Carolina have been heat sterilized. This is expected to eliminate the risk of microbial infections such as salmonellosis. As is always advised when working in the lab, though, we need to use good and prudent safety practices to minimize the possibility of any sort of safety risk. Using sterilized owl pellets and enforcing standard lab safety practices make owl pellet dissection a safe and rewarding activity that students will never forget!
