When I walked into my vet’s clinic last week, I was surprised to see a large branch of Blackbrush in one corner. My first thought was that they had decided to use a native shrub as a Christmas tree (a practice I am coming to love!), but this was a rather scrawny specimen of Blackbrush. Plus, it had a large gray mass in the shrub’s center. What was this thing?

I quickly realized that the papery mass was an old nest of a colony of Mexican Honey Wasps. The wasps had long since abandoned this nest, but the shell remained. Pieces of the outer wrapper had fallen off, and the chambers for storing honey and raising young wasps were visible. Someone in the vet’s office had collected this nest. Why not? It was fascinating, especially when you knew what it was!

Mexican Honey Wasps (Brachygastra mellifica) are found in North and South America, but they have only moved into South Texas for the last 50 years. Like honeybees, they are social insects that live together in a colony. Mexican Honey Wasps are one of the few insect species besides bees that produce honey. 

I recalled my first encounter with these remarkable insects several years ago. My husband and I had gone to photograph an active nest. I had read that these wasps are relatively mild-mannered as far as vespid wasps go. The website said that you can get quite close to a nest if you do not harm it. (Somehow, I interpreted this comment as “they would not sting.”) So, we got pretty close, and I jostled a limb slightly.

Uh-oh!  The wasps let out a soft hissing sound reminiscent of a soda being opened. I pulled a persimmon limb aside to get a better look. Again, the hiss. They had warned me, and they had had enough. One of the wasps zapped me on the neck. It stung, of course, but I laughed it off. After all, I am a Texas Master Naturalist…and a big girl. But the wasp’s sting kept on stinging and hurting for hours. 

I don’t know who came up with the idea to try to get a bit of the wasps’ honey for a taste. But yes, that is what we did. My husband poked the nest with a sharp stick. After we ran out of range (or so we thought), we tasted the tip of the stick. A distinct, strongly-scented honey was evident. But those wasps didn’t want to share. One stung my husband on his head, and another one got me. It was time to leave.

With my newfound respect for Mexican Honey Wasps, I decided to learn more about these insects. Much information can be found on the wasps’ value as pollinators, pest controllers and honey producers. There was very little about their stinging ability except for a note that some Brazilian tribes used them as a rite of passage into manhood. (It figures.)

Mexican Honey Wasp nests contain large stores of palatable honey. Native peoples harvest the honey by cutting off the bottom of the nest, leaving the top still attached to the tree. The wasps rebuild the nest, allowing for exploitation again next year. Some farmers become “vespiculturists” by taking the whole nests when small and relocating them to their gardens. Periodically, the wasp farmers oust the insects with smoke, chop open the nest to get the honey, and allow the wasps to return and rebuild the colony.

In his Latin American Insects and Entomology (1993), Charles Hogue describes the nest-building process. The wasps build semi-concentric rings of combs that they suspend from a branch. They make the combs of “a relatively fragile paper-like material which they produce by chewing wood fibers and mixing them with salivary secretions.” The outer surface of the nest is a baglike envelope of a much more robust version of “wasp paper.”  There is usually only a single entrance to the nest near the bottom of the bag. Newly founded nests reach “smallish football-size in about 30 to 40 days.” Mature nests can be up to three feet long and contain as much as five pounds of honey.

Foraging workers visit flowers to gather nectar. Pollen sticks to their hairy bodies as well. At the nest, other worker wasps transport these provisions to the interior. Much of it is stored as winter food. Developing larvae are fed an exclusive diet of honey and pollen, which is unusual among wasp species. 

Like most wasps, Mexican honey wasps are predators at least part of the time. Although they gather nectar and pollen from flowers, these wasps also prey on various insect pests. The psyllid Diaphorina citra is a very destructive pest in citrus groves. D. Citra makes the fruit inedible and slowly destroys the citrus trees. This insect is common, especially in the late summer. Mexican Honey Wasps feast on these psyllids and decimate their populations. This behavior makes the wasps a very effective biological control agent for citrus farmers.

Perhaps the Mexican honey wasp’s most valuable contribution is as a pollinator. Not only do they pollinate many native plants, but they are also highly beneficial in avocado and citrus orchards. Before the introduction of the honeybee to the Americas, stingless bees and wasps were the chief pollinators for the avocado tree. 

A mature colony of Mexican Honey Wasps can have anywhere from 3,000 to 20,000 individuals. A perennial nest usually lasts about three years before the colony moves on. During that time, the numerous queens produce thousands of worker wasps. These wasps are valuable pollinators, predators of pest species and honey producers. However, I strongly urge you NOT to provoke them!