Monarch Butterflies in Houston
Resources and FAQs from HMNS Cockrell Butterfly Center
The HMNS Cockrell Butterfly Center is dedicated to providing resources for learning about Monarch Butterflies. Our curated collection of reference materials and links covers everything from their endangered status and migration behaviors to creating a butterfly-friendly garden. We also feature a FAQ section to tackle your most common questions.
Common Questions We Hear about Monarchs
Yes, and no. The North American migratory subspecies of monarchs (Danaus plexippus plexippus) was recently listed as endangered. There are two populations of migratory monarchs in the United States, eastern and western which are separated by the Rocky Mountains. The eastern population is most well known for its long journey to Mexico while the western population’s overwintering sites are in California. Though both populations have been in decline, it is the western population that has caused the most concern recently. Latest census numbers suggest that the population has declined by over 99%. Non-migratory populations that overwinter in Florida, Arizona, and along the Gulf Coast were not included in determining population trends, nor were the individuals found in the wild in various countries around the world. The monarch butterfly species (Danaus plexippus) is not listed as endangered, but those individuals that migrate in North America have been added to the red list to prevent further decline. For further information, please visit:
Yes! We see migratory monarchs during the spring and fall.
Houston and the surrounding area has a small population of monarch butterflies that do not migrate. They live here year round!
Unfortunately, the Cockrell Butterfly Center’s environment is not ideal for monarch butterflies. It is best to release them outside in their native habitat.
Try to release them in a sunny spot, preferably on a day that is above 50 degrees Fahrenheit. Do not be surprised if they do not fly away immediately, they’ll do so when they’re ready!
We do not have the ability to take in injured or deformed butterflies. If found outside, we recommend leaving it and letting nature take its course. If you have already rescued the butterfly or it is one that you raised, we suggest one of the following options:
- You can keep it in a container with access to food to live out its life. A cotton ball in a dish soaked in hummingbird nectar or orange slices work well. Make sure you have plenty of twigs for the butterfly to climb on.
- Humanely euthanize the butterfly. You can do this by placing it in the freezer for a minimum of 24 hours. This will slowly and painlessly shutdown the butterfly’s systems.
Unfortunately, we do not have the facilities to adopt caterpillars. We recommend one of the following options:
- You can check our resources page below for a list of local nurseries that may have surplus milkweed to purchase to feed your butterflies.
- If your caterpillars are large, you can try feeding slices of butternut squash or pumpkin. This should give them enough nutrition to pupate.
Tropical milkweed has become quite controversial during the past couple of years. Though it grows fast and is easy to propagate, it does not die back in the fall like native milkweeds do. This is thought to confuse monarchs during their migration while also allowing diseases such as OE to persist and multiply during the winter. To address these concerns, we suggest cutting it back mid-November 4-6 inches from the ground.
Ophryocystis elektroscirrha, more simply known as OE, is a debilitating protozoan parasite known to infect milkweed feeding butterflies such as monarchs and their relatives. Learn more about OE and it’s affects on Monarch butterflies.
Never use any sort of insecticides on plants in or near your butterfly garden!
If you have the correct nectar and host plants, monarchs will find you! Sometimes it just takes them a while.
If the caterpillars were all very large, they may have wandered off the host plant to find a secure place to pupate. However, monarch butterflies in all stages are a pillar of the food chain. Many insects and other animals use them as a food source, even though they’re poisonous.
If it’s the fall and you see a monarch butterfly laying eggs on your milkweed, it more than likely is one of our resident monarchs and not one belonging to the migratory population. Migratory monarchs go into a reproductive diapause, meaning they don’t mate or lay eggs until the spring.
Resources about Monarch Butterflies
Citizen Science Projects
- Monarch Larva Monitoring Project (MLMP)
- Integrated Monarch Monitoring Program
- Journey North
- Monarch Watch (Monarch Tagging)
- BAMONA (Butterflies and Moths of North America)
- NABA (North American Butterfly Association)
- Project Monarch Health
- The Xerces Society
- Texas Butterfly Monitoring Network