A sudden rise of dead cockroaches in the house means that there is a new predator in the house that is feeding on them, especially if you find that the dead roaches are scattered in pieces.
If the roaches seem to have died without any physical dents, then they are feeding on something toxic. This could be the reason why there are dead cockroaches in your house.
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6 Causes of dead cockroaches at home
Finding only dead cockroaches in your house is a sign that you are either succeeding at killing them or there is something that is killing and eating them. below are 6 reasons why you may keep finding only dead roaches in your house.
| Reason | Chances By Percentage | Reasons | |
| 1. | Roaches Playing Dead | 60% | This happens when you suddenly switch on the lights at night. Roaches act dead so that you don’t kill them. |
| 2. | Rat infestation | 80% | When rats lack food because they are many in numbers, they will kill and feed on roaches. |
| 3. | Lizards & geckos infestation | 85% | An increase in the number of those predators will make them hunt and kill roaches for food. |
| 4. | Fire Ants | 40% | This rarely happens. If it does, you will find dead roaches that are killed and left behind by the ants. |
| 5. | Dehydration | 25% | Cockroaches can not go beyond a week without water. If dehydrated, they will die. |
| 6. | Roach infestation | 90% | When there is a large number of roaches at your place, you will keep finding them dead in the open because they can no longer fit in their hideouts. |
1. Cockroaches playing dead
It is interesting that cockroaches can play dead and this helps them a lot in survival. When you surprise a grown roach, it can hold its breath for several minutes to trick you. After your sweep it away, it will bounce back on its feet and flee for safety. You may think that you are only finding dead roaches but instead, they are just tricking you.
Naturally, cockroaches do not like too much light and this is why they only come out at night after you have switched off the lights. When you suddenly open the lights and they scatter for safety, some of them may fall on their backs. This is when they will act dead so that you leave them alone.
2. Rat infestation will make you find dead roaches
An increase in the number of dead roaches at home means that you have rats in your house and they are starved.
If there are rats in your house and they cannot find food, they will resort to eating insects and roaches because they are an easy meal that will satisfy them fast. Yes, it will be an advantage that the roaches are dying out but the rats will be another thing you may want to deal with.
This is because after they are done eating the roaches, they will start to eat your clothes, carpets, curtains, and other valuables that you really like.
3. House lizards & geckos will make you find dead cockroaches
Cockroaches are one of the house lizard’s favorite meals especially when they are starved. If you have lots of geckos and house lizards at home, they will start hunting down cockroaches at night.
You will then notice cockroach wings all over the place since lizards have an of leaving them behind after eating the roaches. Using cockroach spray to kill lizards will also make you find only dead roaches at home.
There are other types of roaches that produce milk for their young ones and those are the ones that predators love to eat.
They are a rich source of proteins and sweet to the predators at the same time. This makes them irresistible to mice and house lizards including the geckos.
Rats and house lizards can survive on female cockroaches that lactate alone because they have enough supplements that they need. They are also rich in vitamins and amino acids which will keep their predators alive and healthy.
4. Dead roaches can be a sign of fire ant’s invasion
Fire ants will never spare anything with meat including cockroaches. In fact, they will kill feed on them as they sweep the area for any food. If fire ants gain access into your house or garage, they attack any crawling insects.
So if you find dead roaches and other crawling insects, then you may want to check the trail and ensure that those deadly ants are not camping in one corner of your house.
Simply follow their trail since they will always eat while on the move and leave the evidence behind.
When you suddenly find several dead cockroaches both in the house and outside, it means that the ants were killing and feeding on them while on the move.
5. Dehydration
When cockroaches are dehydrated, they will even come out during the day to look for water because they cannot survive for long without it.
If you keep the house dry and they have a good hiding place, you will only find dead cockroaches because they will crawl out and die in the open while trying to look for water.
It is not easy to starve roaches to death because they are cold-blooded and can stay for over a month without food.
This means that during that window, they shall have secured a meal and there are very minimal chances that they will lack since they scavenge eat almost anything.
However, it has been studied and proven that they cannot go for more than 7-8 days without water.
Dehydration is one of their weakness and they will even move out of your house if there is no dark, moist area that they can hide in. This is one of the reasons why they like hiding in water dispensers, drainage, toilet, and under the sink.
6. Cockroach infestation
If you keep finding dead cockroaches only in your house, it means there is a rise in the number of roaches that are breading in your place.
You should therefore consider moving things like cookers and checking the dark areas of your cupboards for signs of any eggs that they keep laying. Those bugs breed so fast and you may want to learn how to eliminate them as fast as possible.
Changing the type of dish soap that you use may also flush them out because roaches hate soapy water and this will make them come out of the drains to die out in the open.
Boric acid cockroach bait will cause dead cockroaches
Boric acid cockroach bait will make you find only dead roaches because When you trick cockroaches into eating boric acid, they will die a slow death.
This means that they will not die immediately so they will continue hiding. After some time, they will crawl out and die while looking for water since the boric acid will slowly poison and dehydrate them.
Boric acid will also kill cockroaches because it will slowly dissolve their cuticle wax which helps in keeping them dehydrated. This will work slowly and you will only find them dead latter.
The fact that boric acid powder does not kill cockroaches instantly makes it one of the best baits. When they return to their hideout and mingle with others, those will also die. This is one of the best ways to eliminate roaches in their hideouts.
The best way to make an effect boric acid bait is to mix ½ cup of boric acid powder with ¼ of sugar and ¼ of flour. Roaches love flour and sugar and they will not resist eating those. They will also return to their hideouts and their young ones will also be wiped out there.
Why do roaches come out to die?
Cockroaches come out to die because have small pores all over their body that they use to breathe and when those are blocked, they try to find more air in the open space while moving since they cannot stay in one place while suffocating.
Cockroaches will hide but eventually come out to die in the open because they are trying to escape from the fumes that were blocking their breathing system after spraying.
Roaches breathe through their skin and this is why they can even survive for some time without their head. When roaches are exposed to bleach, they get dehydrated so fast and this will make them restless. They end up coming out and you will find them dead.
In most cases, cockroaches will die after some time if you do not spray them directly. This also depends on the kind of spray you are using to eliminate them.
If you know their hideouts and you spray them, they may not come out immediately and this is why you will find them dead.
Reference:
- The University of Nebraska, Lincoln: Cockroach Control
- Science Alert: Cockroach Milk by Jacinta Bowler
- National Pesticide Information Centre: Boric Acid Technical Fact Sheet
