Praying mantises are known for their unique appearance and predatory nature. Their life cycle begins with a specialized egg case, called an ootheca. This article explains how to determine if a mantis ootheca has hatched.
Understanding the Mantis Egg Case (Ootheca)
A praying mantis ootheca is a structure designed to protect developing eggs. It typically has a foamy, papery, or bubbly texture, resembling spray foam insulation. Unhatched oothecae are typically white, tan, or brown, camouflaging them against natural backgrounds like vegetation or bark.
The size and shape of an ootheca can vary depending on the mantis species, but they generally range from 1 to 5 centimeters (0.4 to 2 inches) in length. Females typically attach these cases to various surfaces, including plant stems, twigs, walls, fences, or house siding. The frothy substance secreted by the female hardens quickly, forming a tough, protective casing that insulates the eggs from environmental hazards.
Key Indicators of Hatching
Identifying a hatched ootheca involves looking for specific visual cues. One primary indicator is small, irregular holes or tears on the ootheca’s surface. These openings are where tiny mantis nymphs have chewed their way out.
The ootheca may also have a “frayed” or “shredded” texture, especially along a seam or edge, resulting from the nymphs’ emergence. Fine “sawdust” or remnants of the case material might be seen clinging to the ootheca, indicating recent hatching activity.
The most definitive sign of hatching is the presence of the mantis nymphs themselves. These newly emerged mantises are miniature versions of the adults, often only a few millimeters long and can appear translucent or yellowish-cream. They are very active, quickly dispersing from the ootheca once they emerge. You might also find shed exoskeletons, known as molts, near the ootheca, which are left behind as the nymphs grow and shed their outer layers.
What to Do After Hatching
Once a praying mantis ootheca has hatched, next steps depend on whether it was found in nature or kept for observation. An empty ootheca can be left in its natural location, as it no longer serves a purpose. If desired, it can also be removed.
For newly hatched nymphs, considerations involve their environment and food source. Outdoors, nymphs naturally disperse into surrounding vegetation to find small insects. Indoors, they require a suitable environment and tiny food, such as flightless fruit flies, as they are very small and voracious eaters. Provide sufficient space and separate the nymphs, as they can be cannibalistic, especially if food is scarce. Vertical surfaces like sticks or mesh are important for them to successfully molt.