by Carlos de la Rosa
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I got the message late on a Monday evening. I had been living in Catalina for less than four months, and already felt a bit overwhelmed by the complexity of the Island. I felt especially challenged by the Island’s amazing biology which I had started to experience by hiking its trails through canyons and valleys filled with species new to me. I had already begun the exciting but long road to learning this flora and fauna and felt energized about the prospect of cataloging, photographing, protecting, and learning about them.
In the e-mail, one of my new Island friends said “Could you identify this creature for me? It appeared in my patio and I had never seen one of them before.” Attached to the e-mail was a slightly over-exposed photograph of a walkingstick or stick insect. Nothing to write home about, I thought. Walkingsticks are fairly common, right? Wrong! When I looked at it closer and started my little research on the Internet and our wildlife file cabinets, I started to find the hidden stories. This was my first foray into the world of Catalina’s endemic insects, a few species that over the last century or so, have been found to live and thrive on the Island and nowhere else in the world.
The scarcely two-inch long stick insect happened to be one of these species. The Catalina walkingstick, known by its mouthful of a scientific name as Pseudosermyle catalinae, has been collected only a few times, not just because it is rare, but because it is very hard to see! They look uncannily like the little branches and twigs of the plants they sit on. It is only when they take a hike away from their host plants that they temporarily lose their camouflage and become visible to us. Our particular species was described and named for the first time in 1981 and, since then, only occasionally seen and collected by entomologists and Island naturalists. It lives its quiet life largely unnoticed by predators and naturalists. It belongs to the order Phasmatodea, the “phantom or ghost insects” because it literally disappears among the sticks and leaves that they normally rest upon.
The walkingstick walk is a great example of a behavior that enhances its appearance. While immobile, the walkingstick looks like a little twig, sticking out like any other dry twig on a plant. Its long antennae are either held close to the body or extended out, very much like the thinner end of a “stick.” The deception is perfect. When it needs to move, it does so with slow, measured steps, balancing its body back and forth at each step, much like what you would see the wind do with a twig that’s about to fall from the tree. A slow pendulous movement, pulsing and natural. Again, the trick works well and the walkingstick remains unnoticed under its cloak of invisibility, even to the trained eye of a bug biologist. Feeding on leaves, the Catalina walkingstick lives a quiet, barely perceptible life among the Island’s native plants.
More robust and visible, although almost equally private, is another one of Catalina’s unique insects, the Catalina shield-backed katydid (Neduba propsti). Also known as Propst shield-backed katydid, it was named in honor of the Catalina Island Conservancy’s second President, Douglas Propst, who lived a large portion of his life in the Island he loved so much. It is a great honor to have an animal or a plant named after you, a little bit of immortality that endures beyond our short, busy lives. That is, until some other biologist reviews the taxonomy and changes the name to something else. It happens, but not that often.
Anyway, this katydid’s main distinguishing characteristic is a strong, knobby plate on its back that looks much like a shield, thus its given name and that protects its short wings. But, a brown katydid? Most katydids are green in color, which helps them blend well in their surroundings. In Catalina, green is not the color of choice for a terrestrial insect, largely because most of the Island is a palette of brown shades and tones, at least for most of the year. So, it pays for an insect to be inconspicuous and blend with its environment, and the shield-backed katydid does this admirably well. There are a couple of related species and subspecies of Neduba in other Channel Islands, all seemingly confined to each island, and all equally secretive in their life styles. To see photographs and additional information about our unique species, please visit the following website: https://entnemdept.ifas.ufl.edu/walker/buzz/149a.htm. Pay attention to the male’s song. It is so subtle that only young people can hear it. Older adults have lost the capacity to hear these superfine sounds. I know, I tried to listen to one in a terrarium and couldn’t hear it, while two younger naturalists could hear it clearly.
The world of Catalina’s endemic insects is a world still to be explored. There are several other insects already determined to be unique to the Island, like four species of scarab beetles, two butterflies and a yet-to-be-named species of Jerusalem cricket. But knowing now what I know about the Island, the history of the entomological explorations and the diversity of habitats across this isolated bit of land, I can confidently say that we have barely scratched the surface. There are more Catalina’s endemic insects out there, hiding in the littler of the ironwoods, in the slowly drying pools after the scarce rains, under the kelp that wash ashore on its beaches, and in the patches of oak forests deep in the canyons, waiting to be discovered, studied, described and their secrets unfolded. For a biologist like me, Catalina is not just a great place to live, but a great place to explore, share and entice others to study and learn from it. It will be through this learning and research that the secrets of the Island will come to light, for all its residents and visitors to learn about and enjoy.
Cazuela 
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