{"id":17429,"date":"2026-10-30T09:02:39","date_gmt":"2026-10-30T09:02:39","guid":{"rendered":"https:\/\/blog.cwf-fcf.org\/?p=17429"},"modified":"2026-10-28T16:15:58","modified_gmt":"2026-10-28T16:15:58","slug":"monarch-butterfly-tagging-your-questions-answered","status":"publish","type":"post","link":"https:\/\/blog.cwf-fcf.org\/index.php\/en\/monarch-butterfly-tagging-your-questions-answered\/","title":{"rendered":"Monarch Butterfly Tagging: Your Questions Answered!"},"content":{"rendered":"

Our monarch butterfly tagging project has sparked lots of curiosity, and we\u2019re excited to answer your questions! <\/span><\/h2>\n

This summer, the Canadian Wildlife Federation (CWF), <\/span>in collaboration with Environment and Climate Change Canada and the Norris Lab from University of Guelph, tag<\/span>ged<\/span> migrating Monarch Butterflies using new Bluetooth tracking technology (BluMorpho) tags from Cellular Tracking Technologies. As the butterflies begin their incredible journey south to Mexico, the tags will help us learn more about Monarch Butterfly migration and help us make decisions to best conserve this incredible species. Curious about how the tags work, how they\u2019re attached, or what researchers hope to learn? <\/span><\/p>\n

Read on for answers to some of the most frequently asked questions about our monarch tagging project!<\/span>\u00a0<\/span><\/p>\n

About the Tags<\/span><\/b><\/h3>\n
\"Look
Look closely at the monarch\u2019s back in this photo. See the tiny solar panel? This panel provides energy for the antenna to ping off of nearby cellphones and send a location signal. \u00a9Vincent Fyson | CWF<\/figcaption><\/figure>\n

How Do the Tags Work? <\/span>\u00a0<\/span><\/h4>\n

The BluMorpho tags use a 2.4GHz frequency range, making the antenna very small and very efficient. The tags are detected using Bluetooth technology on smart phones, Motus stations, and other networks which record the time and location where the detection occurred. The tags are 100% solar-powered. No battery means that the tag is lighter than if it needed a battery, and the tag can transmit indefinitely as long as it is visible to the sun.\u00a0<\/span>\u00a0<\/span><\/p>\n

How Much Do the Tags Weigh? <\/span>\u00a0<\/span><\/h4>\n

The BluMorpho tag that we used is the lightest-weight radio tracking tag weighing 60mg, or 0.06g\u2014less than a grain of rice!<\/span>\u00a0<\/span><\/p>\n

Where Can I Buy Them? <\/span>\u00a0<\/span><\/h4>\n

The tags were created for use by scientists to help increase our understanding about Monarch migration and habitat needs, ultimately to help its recovery. We’re using data collected from the tags to help further scientific research for this declining species.\u202fSince monarchs are very delicate, only trained professionals with the proper handling permits should participate in tagging.\u00a0<\/span>\u00a0<\/span><\/p>\n

What is the Difference Between These Tags and the Monarch Watch Sticker Tags? <\/span>\u00a0<\/span><\/h4>\n

Sticker tags contain no electronics and instead rely on being found and reported back to Monarch Watch. These tags transmit continuously and provide data remotely as long as they are in range of a receiver (radio tower, cell phone, etc.). These tags are slightly larger to account for the technology, but instead of attaching to the monarch wing, the tag is attached to the back of the thorax.<\/span>\u00a0<\/span><\/p>\n

About the Monarch Butterfly <\/span><\/b>\u00a0<\/span><\/p>\n

\"\"<\/p>\n

How Does the Tag Get Attached to the Monarch? Is it Traumatizing to the Monarch? <\/span>\u00a0<\/span><\/h4>\n

We used a non-toxic, flexible adhesive to secure the tag to the back of the butterfly. Part of the tagging protocol includes chilling the monarch for a few minutes so that they naturally calm down (the same process that occurs during cold evenings\/nights when the monarchs naturally become less mobile) which helps avoid any injury or struggle. Once the tag is secured, the monarch is given time to warm up in the sun before being released.\u00a0<\/span>\u00a0<\/span><\/p>\n

Can They Even Carry the Tag all the Way to Mexico? Isn\u2019t This an Unneeded, Inconvenient Weight? <\/span>\u00a0<\/span><\/h4>\n

The BluMorpho tags are 0.06g (or 60mg, less than the weight of a grain of rice!). The butterflies are weighed before tagging (along with the tags to ensure the weight is within the acceptable range) to ensure that they are strong enough to carry the tag, but not too heavy. Monarchs who are too heavy or too light to be tagged are released to continue their migration.\u00a0<\/span>\u00a0<\/span><\/p>\n

How Does the Tag Impact Their Flight or Behaviour? <\/span>\u00a0<\/span><\/h4>\n

This tag, along with others, were tested for impacts on the ability of the butterfly to make the flight to Mexico and did not find evidence that the tag would impact flight or behaviour in a significant way. The study is currently under review and once it has been published, we will share the link.<\/span>\u00a0<\/span><\/p>\n

What Happened to the Monarch if the Tag Stops Transmitting a Signal? <\/span>\u00a0<\/span><\/h4>\n

A number of things could have happened to the monarch if the tag is no longer being detected. The tag may have fallen off and landed upside down. It could be covered by a shadow or debris, or the monarch is roosting with their wings closed, so the sun is not reaching the solar panel. It could also mean that the monarch has been predated or simply outside the range of cellphones and so is not being detected.<\/span>\u00a0<\/span><\/p>\n

How do the monarchs know where to go?\u00a0<\/span>\u00a0<\/span><\/h4>\n

That is a great question and one that humans have tried to answer for decades. Since they are multiple generations away from their ancestors who flew to Mexico the previous fall, migrating monarchs must have some natural instincts that help them find overwintering sites. The scientific consensus (and most studied hypothesis) is that they use celestial cues (from the sun) in combination with the earth\u2019s magnetic field. Read more about the science behind monarch migration ><\/a><\/span>\u00a0<\/span><\/p>\n

If we already know where they are headed, why are we interfering by tagging them?\u00a0<\/span>\u00a0<\/span><\/h4>\n

The tags can help us answer many questions that we don\u2019t already know about monarch butterflies, and the answers to these questions can help us make decisions to better conserve this endangered species. Some of these questions include:\u00a0<\/span>\u00a0<\/span><\/p>\n