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Karner Blue Butterfly


Peter J. Tolson

Toledo Zoo


Karner blue butterfly research/management work:

Reintroduction of the Karner blue butterfly to the Oak Openings of Northwestern Ohio; conservation breeding protocols for the Karner blue butterfly.



1. Adult Karner blue butterfly life span can be extended to up to 30 days by daily hand feeding of adults.

2. Host plant fertilization results in pupae that are significantly longer and heavier than those raised on non-fertilized plants.

3. Adult females raised on fertilized host plants as larvae have significantly higher fertility and fecundity.

4. Development of larvae can be delayed by up to three weeks by cooler temperatures to synchronize releases.


Work Area: Ohio


Contact Information:

Department of Conservation and Research
The Toledo Zoo
P.O. Box 140130
Toledo, OH 43614-0801

(419) 385-5721 x2112



Propagation Handbook for the Karner Blue Butterfly (PDF)




Last updated: July 19, 2016