Cockroaches leave their sign wherever they go. Cockroach eggs, egg sacs, droppings, and shed exoskeletons, are all signs of a roach infestation. Although less than 1% of the approximately 4,500 species of cockroach ever bother humans, we still see them all as dirty pests. In truth, cockroaches play a vital role in breaking down dead plant and animal matter. But, when they come into our homes, they tend to cause their fair share of problems.
Here, we’ll learn everything there is to know about cockroach eggs and egg sacs. We’ll begin by learning about the different methods roaches use to reproduce. Then, we’ll examine cockroach eggs and egg sacs, and how to identify them. After that, we’ll go into detail about how many eggs are in each egg sack, and whether or not you can actually see these minuscule shells. Then, we’ll analyze methods for getting rid of, and preventing, cockroach eggs in the first place.
Do Cockroaches Have Egg Sacs?
Cockroaches reproduce just like any other animal, but not in the same way that humans do. Where humans have one, sometimes two or three, offspring at a time, cockroaches can produce hundreds of larvae per year. All roaches start as eggs encased in egg cases that look a lot like tiny, dried out kidney beans. These egg cases are either left in a safe place, carried with the mother, or kept inside the mother for the duration of incubation.
Some cockroach eggs never exit the mother’s body. Species like the Australian rhinoceros cockroach actually keep the eggs, and egg case, inside during incubation. The baby cockroaches, also known as nymphs, hatch inside the mother. She then gives birth to live, translucently white, young. This process is known as ovoviviparity, and cockroaches that do it are known as ovoviviparous roaches.
What Do Cockroach Egg Sacs Look Like?
Cockroach egg sacs aren’t quite the same as spider egg sacs. For one, they’re called egg cases, rather than sacs. Each species’ egg case has a unique appearance. The American cockroach’s egg case looks like a dried kidney bean, while the Oriental cockroach’s egg case has a much more rectangular shape. Egg cases are long and thin, and often have striations, like stripes, down their length. They can sometimes be found stuck to the undersides or furniture, or in warm, dark, protected areas.
The German cockroach’s egg sack is exceptionally long and thin. It’s also very light colored, almost an amber brown, with distinct dark brown striations. Brown-banded cockroach egg sacs look like tiny coffee beans.
How Many Eggs Are In a Cockroach Egg Sack?
The number of eggs per egg sack varies depending on the species, just like the amount of time it takes to incubate the eggs. German cockroaches are prolific breeders, and may have up to 50 eggs per egg case. American cockroaches, on the other hand, typically have between 12-16 eggs per egg case. Females make up for having so few eggs per case by producing many egg cases—up to 14 per female.
One species of roach, the Dubia cockroach, is a particularly fecund breeder. They’re ovoviviparous, and can hatch and birth up to 40 baby cockroaches every single month. This fecundity makes them a popular species of feeder roach. Feeder roaches are bred and sold to owners of exotic pets as feed.
Can You See Cockroach Eggs?
The eggs and egg sacs of many insects are so small that they’re difficult for humans to see; this is not the case with cockroach eggs. Though small, cockroach eggs are not invisible to the naked eye. Cockroach eggs often look like small, dried kidney beans, or darkly colored grains of rice. You won’t generally find them out in the open though. If female roaches don’t carry the egg sacs with them, they usually leave them in safe, dark places. You may see cockroach egg sacs if you move a refrigerator, or clear away clutter.
How Do You Know If a Roach Egg Has Hatched?
Full cockroach egg cases are best compared to ripe pea pods. When the eggs are inside, incubating, the egg case looks like a pea pod stuffed with ripe peas. It’s full, slightly bulbous, and firm. When the baby cockroaches hatch out, they leave the egg case empty.
An empty egg case looks much the same as an empty pea pod: deflated, sunken, and shriveled. If you’re not sure whether the egg sack is full or not, and you have a strong stomach, you can try squeezing it, and see what happens. If you do, be sure to wear gloves, and wash your hands afterwards.
How to Get Rid of Cockroach Egg Sacs
If you find cockroach egg sacs in your home or business, you should take immediate steps to get rid of them. Even if you don’t have any particular problem with cockroaches, most species that infest homes can cause severe damage and create unhealthy environments for humans.
Your first step may be to call a professional pest exterminator who can diagnose and take care of the infestation for you. Or, if you prefer doing things yourself, you may want to start with roach traps. Use the traps to determine where the worst infestation is, then use pesticides to kill the cockroaches.
If you decide to take care of the roaches yourself, use extreme caution when administering the pesticides; they’re toxic to both people and pets.
Preventing Roach Eggs
Cockroaches love dark, damp, warm places. They need sources of food and water, and a good place to hide. To minimize the potential for infestation, be sure to clean up all food and garbage in a timely manner. Keep clutter to a minimum, and ensure that under the sink cabinets are kept clean and dry.
How Many Species of Cockroaches Are There?
Did the subject of cockroach eggs cause you to pause and wonder how many types of cockroaches there are in the U.S. or worldwide? Believe it or not, there are over 4,500 different types of cockroaches on the planet! Maybe it’s not that surprising, given the jokes surrounding how cockroaches would likely survive a nuclear holocaust or any other type of catastrophe just fine.
In the United States, there are 69 species. Types that seem to be spoken of the most include American cockroaches, German cockroaches, brown-banded cockroaches, smoky brown cockroaches, and Oriental cockroaches (often referred to as waterbugs). Other American varieties are the Pennsylvania wood cockroach, three-lined cockroach, field cockroach, and Florida woods cockroach.
If cockroaches give you the heebie-jeebies, consider the top 5 largest cockroaches in the world:
- Megaloblatta Longipennis – largest in the world at 3.5 inches long, 1.5 inches wide, and an 8-inch wingspan
- Giant Burrowing Cockroach – 3.1 inches long, weight of 1.5 ounces
- Blaberus giganteus
- Madagascar Hissing Cockroach
- Death’s Head Cockroach
The photo featured at the top of this post is © iStock.com/VitalisG
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