You are enjoying some outdoor time with friends or family when suddenly, your arm begins to itch. As you start to scratch the new red bump on your skin, you realize it is a mosquito bite. “Why,” you ask yourself, “do mosquitoes have to bite?”

Many scientists have researched mosquito behavior to understand why mosquitoes bite. While many theories are debated upon, there are a few facts that can be stated with certainty.


Not all mosquitoes bite. Only female mosquitoes take blood meals. This is because they need the protein in blood, composed of amino acids, to develop eggs. Some female mosquitoes require a blood meal to reproduce the first time. All female mosquitoes require a blood meal to reproduce a second time.

Human blood is the meal of choice for many female mosquitoes, although the reasons for this are not fully understood. Many scientists believe that humans have ingredients in their blood that lead to the more successful production of larvae. However, this type of mosquito behavior is unpredictable because not all mosquitoes prefer humans.

Every time a female mosquito bites, she takes about 3 milligrams of blood. This number is trivial in comparison to the amount of blood in the human body, but it can equal up to four times her actual weight. It is the equivalent to one human eating 400 pounds of steak, according to the Mallis Handbook of Pest Control by Arnold Mallis.

While the amount of blood mosquitoes draw is insignificant to many humans, if numerous mosquitoes are all feeding off of the same food source, the amount of blood lost can be dangerous for some. According to Mallis, cases of animals dying after losing too much blood to a gang of mosquitoes have been reported.

While female mosquitoes need blood for egg production, they do not use it for their own nutritional benefit. Instead, both male and female mosquitoes feed on nectar and water.

Many people believe that they are more popular amongst mosquitoes than others. While much research has been done to uncover this mosquito behavior, a lot of questions remain unanswered. A number of researchers have demonstrated that mosquitoes are attracted to sweat or bacteria on the skin. Other researchers have more specific theories.

In more recent studies, scientists suggested that genes could also play a role. When researchers observed how a group of females would respond to identical twins, who share the same genes, versus fraternal twins, who have different genes, they discovered that identical twins elicited the same response from mosquitoes. Mosquitoes were either very attracted to the identical twins, or not attracted. However, the results from the fraternal twins showed that mosquitoes sometimes favored one fraternal twin over the other. This sheds more light on mosquito behavior and suggests that genes do play a role in levels of attraction.

Concerned about mosquitoes near your home? A pest management professional can better explain different mosquito behavior and develop a solution for your home that will help you get a grip on that itch.

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