Collection Trip to Texas

Reporting live from Texas! 

Occasionally monarch butterflies bring me to Texas during either their fall migration to Mexico or their re-migration back to the U.S. and Canada in the spring. Texas is the last spot to find eastern monarchs in the fall before they cross the border. While you can find them all over Texas, I spend the majority of my time in Hill Country, an area that encompasses Austin and many smaller cities to the west including Kerrville, Llano, and Fredericksburg.  

Catching an actively migrating monarch is tricky if not impossible. They fly relatively high in my experience - certainly higher than my 6 foot net can reach. So if I plan to collect, I focus on areas with many wildflowers. Monarchs feed over the course of their several month long migration south, and a feeding monarch is surprisingly easy to sneak up on. 

I spend most of my time in places that look like this:

What you can't see are the numerous small cacti, grasses with painful burrs, and the large fire ant hills.

On the slow days, when monarchs are in short supply, I might turn my attention to other local butterflies. I justify netting these butterflies as honing my skills, but mostly I find it interesting to have a look at their beautiful wings up close. Hopefully you might enjoy them as well!

The following photos represent some of the most common larger species found in Texas, all of whom I then released. The smaller hairstreaks and blues are difficult to handle for photos while alive due to their small size so I avoided them altogether.  

 

 

 

 

Artificial feeders for butterflies

Perhaps you are like me and raising an absurd number of butterflies - so many butterflies, that feeding them nectar from flowers is out of the question?

In the Kronforst lab, where I am doing my graduate work, we feed our adult butterflies Birds Choice Butterfly Nectar from fake flowers that we make from readily available lab supplies.

**At this point, I'd like to mention that you must teach your butterflies to eat from any artificial feeder. They often will not figure it out on their own! I will do another post on hand feeding and teaching butterflies to eat from artificial feeders soon.**

Monarch butterflies feeding from our fake flower set up.

Monarch butterflies feeding from our fake flower set up.

Making the flowers

1. Sealing

Seal the point of a P20 or P200 pipette tip. We use a Bunsen burner to melt the point, but I could imagine other ways to create a seal - maybe a hot glue gun? 

2. Petals

 Cut a length of colorful tape and fold the sticky sides together to create a non-adhesive sheet. Alternatively, use thin colorful plastic sheeting that is easy to cut through. Next using either scissors or a scrap booking flower shaped punch tool, cut out petals or punch out a flower. The punch will also need to be hole punched in the center, slid onto the pipette tip, and glued in place. If you cut out your petals with scissors, take a bit more tape, arrange three to four petals on the adhesive side and wrap around the open end of the pipette tip.

3. 1.5 ml tube flower holder

Pierce a small hole through the cap of your 1.5 ml tube - I often use old tweezers or small scissors to do this. Now slide the cap onto a length of wire with a diameter slightly wider than that of your tube's hole. Voila! Now you can hang your flowers inside your butterfly cages.

4. Filling the artificial flowers

We fill our flowers using a 5 or 10 ml syringe with a blunt end needle

Sponge and Cup Method

Another option is to pour nectar into the base of a small cup and place a sponge with wide holes in the cup. The butterflies can sit on the sponge, insert their proboscises into the holes, and drink to their hearts' content.

I don't prefer this method as it wastes nectar. Nectar tends to ferment and go bad in a couple days when not refrigerated. The fake flowers use far less nectar, and the butterflies tend to drink up most of the liquid in the flower before it spoils. But assuming you don't have a full scale butterfly operation, you might still prefer this less complicated option.

Butterflies feeding from a yellow sponge soaked in nectar inside a red plastic cup.

Butterflies feeding from a yellow sponge soaked in nectar inside a red plastic cup.

 

 

How to hand pair butterflies (i.e. getting your butterflies to mate now)

If you are trying to set up a butterfly mating and don't have time to wait around for nature to take its course, you can hand pair. When hand pairing two butterflies, you position the male and female bodies facing each other such that the male can easily grab the female's genitalia with his claspers - see this post to get a closer look at male and female butterfly genitalia. 

Why

I frequently hand pair individuals when I need to ensure the survival of a specific group of butterflies, this way I don't run the risk that a butterfly will die before mating takes place. Hand pairing also saves me time and energy; I could either set up four cages with four different couples and hope for a mating to occur naturally, or I can hand pair a single couple which usually leads to fertilized eggs within a day or two.

Who

How well hand pairing works depends on the species. Some butterflies are significantly more difficult to hand pair than others. Sometimes this is due to their size as they are simply so small that it is difficult to handle them. And sometimes their mating strategies involve specific courtship rituals which are not performed when hand pairing. But for many species, including monarchs and swallowtails, hand pairing is a great way to get your next set of eggs a bit faster.

How

Probably most important when hand pairing is to convince the male to open his claspers. There are a number of ways to accomplish this: 1) use a paint brush to lightly brush the male's claspers 2) rub the abdomen of the male against the female's (my personal preference) or 3) place the male in a refrigerator for a minute or two. Number 3 is usually a last resort for me as it takes the butterfly some time to recover and actually clasp the female's abdomen. If the female is too active while you are trying to get the male to attach, you can also cool her down in the refrigerator for a few minutes.

No matter which method you use, any movement of the male's abdomen or claspers is a good sign that he is interested in mating, so keep trying! Sometimes it takes a few tries for the pair to get in the right position.

I'm also including a brief video below of my favorite method for monarchs, rubbing abdomens, as well as this link to a video of the paint brush method.

Here you can see me holding the female on the left and the male on the right. The male has already opened his claspers. I then rest his claspers slightly above the female's genitalia. The male extends his abdomen down to reach and grab the female.  

A couple things to consider before hand pairing:

1. How old are your butterflies? It is always better if the pair of butterflies are in their prime. The very newly eclosed (emerged from their chrysalis) and oldest butterflies might pair but not produce any eggs. Often this means that the male did not successfully transfer a spermatophore to the female, without which she cannot fertilize her eggs.   

2. Have either of your butterflies mated before? In some species, males know when a female has mated before which could make him less inclined. If the male has previously mated, he might not have a new spermatophore yet. Spermatophores are very large constituting 13% of the male's weight in some species.

Finally, patience is key! You might have to experiment a bit to see what works best in your species.

 

Can you tell the difference between male and female butterflies?

Though we can often determine a butterfly's sex by looking at the most obvious differences in its appearance - like the scent spots of the male monarch or wing pattern/color of tiger swallowtails - the best way to distinguish between males and females, particularly if you aren't intimately acquainted with each species, is actually by looking at the butterfly's genitalia. The genitalia are located at the base of a butterfly's abdomen.

The yellow circle marks the male monarch's scent organ. Females do not have these specialized scales.

The yellow circle marks the male monarch's scent organ. Females do not have these specialized scales.

In general, males have claspers which they open and use to grasp the female's abdomen during mating. With the female's abdomen clasped, the butterflies will remain attached until mating is complete. Very occasionally, you might even see this in the wild. I once caught a mating pair of monarchs as the male flew by with a female attached! Hopefully soon, I will have another post on butterfly mating with videos.

Male claspers in the  Papilio  genus (a swallowtail group) usually come to a point when closed. Here they are circled in yellow in  Papilio polyxenes,  commonly known as the black swallowtail. In the photo on the left, you can see I was actually out hunting for monarchs, note the blurry common milkweed at the top and my butterfly net.

Male claspers in the Papilio genus (a swallowtail group) usually come to a point when closed. Here they are circled in yellow in Papilio polyxenes, commonly known as the black swallowtail. In the photo on the left, you can see I was actually out hunting for monarchs, note the blurry common milkweed at the top and my butterfly net.

Papilio polytes  and  Papilio dardanus  males with claspers open.

Papilio polytes and Papilio dardanus males with claspers open.

Females are a bit trickier as you are looking for the absence of claspers. However in some species, like the monarch, you will note a small divot in the last segment of her abdomen. This is where the male actually grabs on during mating. In addition, most female butterflies have rounder abdomens than males, especially obvious when they are carrying many eggs.

A female and male monarch. The differencs between the sexes is highlighted in the yellow circles.

A female and male monarch. The differencs between the sexes is highlighted in the yellow circles.

A female  Papilio polytes  and  Papilio memnon , both native to Asia. 

A female Papilio polytes and Papilio memnon, both native to Asia. 

In some species, you might not be able to easily identify the claspers; in fact, I still have trouble with the Heliconius genus. These butterflies are on the smaller side which also makes a clear picture from my phone camera challenging and are mostly found in Central and South America, though a few species range into Mexico and the southern U.S. 

The female and male abdomen of  Heliconius cydno,  the difference between the female and male are highlighted in yellow. As you can see, male claspers in this species are smaller and difficult to identify. 

The female and male abdomen of Heliconius cydno, the difference between the female and male are highlighted in yellow. As you can see, male claspers in this species are smaller and difficult to identify.