PacSci Perspectives

Eating Us in to House and Home: Stick Insects and Sustainability

Mar 26, 2019

Australian Prickly Stick

Butterflies may take center stage in our Tropical Butterfly House, but Pacific Science Center is also home to a host of other spectacular insects. Take our three species of stick insects for example; these maestros of mimicry and camouflage are soon to be the stars of a new sustainability initiative here on campus.

PacSci is always looking for creative, green solutions, so with that in mind, we’re starting a horticultural experiment. It’s an experiment born of necessity: how do we reliably satisfy the appetites of dozens of walking sticks? Wild stick insects in the American South are infamous for their ability to strip entire trees of their foliage. Rainforest ecosystems depend on these voracious herbivores to assist the pruning and decomposition process that keeps established forests healthy.

How can we provide the best care for our various species of Phasmatodea? Store-bought plants are frequently treated with pesticides that could do serious harm, so that’s out of the question. The current feeding system relies on one of our animal care specialists who collects blackberry brambles from surrounding neighborhoods. As you might imagine, this is a fairly time-consuming process and rather difficult to maintain long-term.

Thus, the next natural step is to grow our own organic greenery. The top contender on the menu is the hearty, aesthetically appealing rose bush. In addition to increasing PacSci’s self-sustainability, new rose bushes would beautify our campus. They would also be easier to handle than blackberry brambles.

However, this experiment is not without its challenges. Fresh branches are necessary on a weekly basis. Depending on how quickly the roses can keep up with this volume, the stick insects might still need supplementary foliage. Not to mention, the insects themselves may not be keen on the new flavor. Like any other living creature, they constitute an unpredictable variable in the equation.

Speaking of our spindly denizens, let’s introduce the cast. The largest and thorniest of the gang is the New Guinea Spiny Sticks. They are surprisingly accommodating and easy to handle— as long as you watch out for the barbs on the male’s hind legs. The Vietnamese Stick Insects are the movers and the shakers, exhibiting the iconic bobbing motion that makes them so hard to spot on a swaying tree branch. The real divas are the Australian Prickly Sticks. If you disturb them on a sensitive day, which is every day, they transform from a crumpled, dead leaf into an intimidating scorpion, arching their abdomen up, emulating a stinger. Their capacity for both camouflage and mimicry makes them especially compelling.

Science is always a process, so stay tuned for an update on our walking sticks and their new home-grown diet!