Wildlife, Little Leapers
Friday, 25 September 2009
Today we're looking at the little insects that could be sharing your home, your bed and even your hair!
Colin Stafford Johnson
Over the past two decades, Stafford-Johnson has tracked and filmed animals all over the world, including jaguars in the Amazon, tigers in India and birds of paradise in New Guinea. In 2006, he won an Emmy for cinematography on the film Mississippi - Tales of the Last River Rat for Discovery Channel. He has also worked with renowned broadcaster and naturalist David Attenborough on the well-received BBC series Planet Earth. He is currently filming the second installment of his RTE show, Living The Wildlife.
Colin will be speaking about four common little insects that sometimes share our homes and bodies with us.
Bedbugs are found all over the house. Apart from your bed, these 5mm long insects can be found in headboards, behind peeling wallpaper, broken plaster, light switches, under carpets and also skirting boards. They are nocturnal and live by feeding on human blood. If living in your mattress they tend to wait until night time and will come out of the mattress and bite you. They usually suck on your blood for up to five minutes before going back into the mattress again. A bed bug bite is usually small and red in colour. They also tend to bite in rows so bites are quite easily identifiable.
They usually lay around 200 - 500 eggs over a two month period. Their mouthparts are specially adapted to pierce human skin and suck blood. The best ways to prevent bed bugs is to keep your bed and rooms of your house clean, paying particular attention to the places mentioned above.
Ticks are parasites that feed on animal and human blood. There are four distinct stages of a tick's development from eggs to larvae to nymph to adults. Between each stage ticks must have a bloodmeal.The whole cycle usually takes about a year from egg to adult. It is easy to confuse the different stages of a tick's development for different species of tick. The body of the female is capable of massive stretching: it can absorb approximately 100 to 200 times its body mass in blood, which increases its volume by a factor of 120.
Ticks inject a toxin that may cause local irritation or a mild allergic reaction, however most tick bites cause little or no symptoms. In some cases ticks can pose a serious threat to human health. Tick borne diseases, tick paralysis and severe allergic reactions, while uncommon, can pose a serious health threat. They target specifically the armpit, groin and back of the knee. However, victims do not feel the bite because the tick also injects a toxin that anaesthetises the area
Around 850 species of tick have been described in the world as a whole. Tick bites are best prevented by staying away from scrub and high-growth areas and sticking to roads and paths. If you want to go off the roads and paths you should wear boots, long trousers and a longsleeved shirt.
Any ticks can then be easily brushed off of the clothing when you come home. Even though you have been appropriately dressed, it is always a good idea to check yourself and your children (and your dog) for ticks when you come home from a walk in the woods. Be aware that ticks look for a place on the body that is dark and warm, where the skin is thin. So remember to look for ticks under your arms, behind your knees, in your crotch and behind your ears!
These are well known as jumping insects and can jump up to 10 inches in height. This is many many times their own height as they are tiny. They are a wingless insect and can be anything from 1mm to 4mm long. They also feed on blood.
After every blood meal a female flea can lay anything from 4 to 8 eggs, they can usually lay several hundred eggs over the course of their lives. Their young can emerge after justb two weeks having completed a larval and pupal stage. However sometimes eggs can lay dormant for up to one year. This happens at times in unoccupied houses, once the house is re - occupied the egges may be disturbed and adults will emerge.
Fleas often bite around the leg and ankles and bites usually number two or three and are usually in a row. These sore bites can also present a risk of spreading disease as fleas move from one host species to the other. These fleas can also be found on animals such as dogs, rats, pigs, deer and foxes.
To prevent fleas it's important to make sure that any animals you come into contact with are clean, especially if they're living in your home with you.
Head lice are tiny bloodsucking parasites that live in human hair. They prefer to attach themselves to the scalp where there is moisture and a high temperature (about 30° C), enabling them to easily suck blood. An adult louse is 2-3 mm long. The female louse is larger than the male. The louse's body is oblong and flat. Its colour can vary from almost transparent to quite dark. Colour differences are partly due to the louse's ability to take on the colour of the hair it lives in, and partly because the louse looks darker after it has sucked blood.
Adult lice can live for about three weeks. During that period a female louse will lay 5-8 eggs per day. Lice eggs are about 0.8 mm long and are laid all the way down near the scalp, where they are nearly glued to the hair stalks. The eggs take 6-9 days to hatch. From the time it hatches, it takes 9-12 days before a female louse can begin to lay eggs.
Head lice can neither fly nor hop, they only crawl. Lice will not voluntarily leave the scalp, unless they can crawl directly over onto another. When lice are spread from person to person, it is usually when the someone's hair touches someone elses. Lice eggs are not contagious. Not even from hair that has fallen out. The eggs are stuck to the hair and are unable to hatch at temperatures under 22° C. Lice can survive up to 48 hours away from the scalp. This means they can spread among people using the same comb, brush, cap, pillowcase/bed etc.
Anyone can be infected with lice. Whether you or your child become "infected" has nothing to do with how cleanly you are. Lice are generally found on children, because they are in close physical contact when they play.
The best way to prevent lice is to check hair once a week and brush through it with a fine tooth comb.