Loving, or at least appreciating, Lubber Grasshoppers is hard for many folks. Gardeners are not fans. In some years, it appears that they show up as small armies, chewing up everything in sight. So, where are their predators? Can we get more of those? The short answer is no.
As with the well-known distasteful defenses of Monarch Butterflies, Lubbers do much the same, and more, to keep would-be predators at bay. As with Monarchs, it starts with their bold warning coloration, that sends the message that I may be easy to spot, but I taste bad. The bad taste comes from toxins obtained or synthesized from the plants they eat. After their first encounter, individual predators learn to avoid them, providing communal protection.
For Monarchs, toxins are sequestered directly from the milkweed plants they ingest, stored in their flesh. In the case of Lubber Grasshoppers, they feed on a wider range of plants from which they sequester or synthesize their suite of toxic chemicals. They do not need to be picky about what they eat – their physiology generates what they need to be distasteful.
These grasshoppers are also one of our largest species, that along with prominent spines on their legs, adds a level of intimidation for most would-be predators. If that doesn’t work, they have a few other tricks to play before being grabbed for a taste test. If disturbed, they will hiss and flare out their fore wings to expose the bright red hind wings underneath to try and scare you. If grabbed, they can emit a foul-smelling froth from their mouths and spiracles – holes on their sides that they use to breathe.
And yet, some vertebrate predators do try and grab these critters, at least once, before they either learn the lesson, or die. The toxins have been shown to invoke vomiting in lizards, and likely others. Some species have been reported to die from the experience. I suspect that the Southern Toad that my friend Emmett spotted with a Lubber in its mouth experienced the same and eventually spit it out.
But, at least one species of bird has figured out how to deal with the toxins. Loggerhead Shrikes are known to impale Lubbers on spines of trees or barbed wire, like they do with many of their prey. Over the course of a day or so, the toxins break down, allowing these birds to feed on the carcass. Birds are smart and this behavior is likely passed on.
But alas, Lubbers are not immune from something that will eat them. Several species of Flesh Flies (Sarcophagids) and Tachinid Flies (Tachinidae) seek them out to lay eggs on them, leaving their larvae to eat them out from the inside over several weeks, with the hopper going about its business. Once mature, the flies emerge from a hole in the grasshopper’s side, with the hopper still clinging to life. Some of you would say, “Serves you right!” Well, it is part of the food chain. A few microorganisms also infect them.
But you have to give Lubbers credit for being tuff critters. With layers of defenses, they survive attacks from a multitude of hungry predators, that learn quickly to avoid the next one, if they survive the first one.
Hope to see you in our great outdoors!
Photo of Southern Toad with Lubber courtesy of Emmett Carstens-Wood