The Superorganism

We have not actually read the new book on social insects by Hoelldoebler and Wilson, but it is on our Christmas list. The Superorganism: The Beauty, Elegance, and Strangeness of Insect Societies looks to be the latest important volume by these award-winning scientists. Bert Hoelldoebler is Foundation Professor at Arizona State University and has been the recipient of both the Pulitzer Prize and the Leinbniz Prize - Germany's most highly endowed research award. Edward O. Wilson is a Harvard professor with nearly fifty years experience, more than twenty books published, and the recipient of two Pulitzer Prizes and the National Medal of Science. The two have teamed up for the second time to explore the world of insects. Eighteen years ago their book The Ants became the definitive scientific study of these diverse creatures. Their latest book expands our knowledge of social insects - ants, bees, wasps and termites. They are identified as superorganisms because they live in tightly knit colonies formed by altruistic cooperation, complex communication, and division of labor. From a scientific and entomological viewpoint, their Superorganism book brings insight to how transitions between levels of evolution have occurred and how life has progressed from simple to complex forms. On a sociological level, perhaps the two scientists give us food for thought on how we interact and function together as humans. 

We would recommend attending a lecture by Hoelldoebler and Wilson tonight, but it takes place in New York City and is sold out. Next best thing: put the book on your Christmas list!

Quiz Answers: Pharaoh Ants

Here are the answers to yesterday's quiz on Pharaoh ants. The hope is that in learning more about these difficult pests, we can work together to control infestations and secure homes against invasion.

1. In the human world, polygynous means more than one wife. In the ant world, it indicates (b) colonies have more than one queen. Mature colonies of Pharaoh ants contain several queens, winged males, workers, eggs, larvae, prepupae and pupae. 

2. Pharaoh ants are usually very small (approximately 1/16 of an inch long), and yellow to light brown in color. One distinguishing characteristic is the (c) three-segmented club at the end of their antennae. 

3. Although Pharaoh ants can be found in apartments, hotels and grocery stores, they are often associated with (a) hospitals. They can be especially troubling in health care areas, as they infest small spaces are are very difficult to eradicate. Unfortunately, they are capable of mechanically transmitting diseases and contaminating sterile materials - making them an especial nuisance in the health care industry.

4. The best way to treat Pharaoh ants is to (c) bait only. For this reason, we recommend you (d) call a pest professional. A successful Pharaoh ant control program will involve intensive baiting using baits that contain insect growth regulators. Unlike the more common Argentine ants, spraying can be counterproductive with a Pharaoh ant infestation. Chemical sprays tend to induce colonies to spread and divide, making control much more difficult.

5. Part of the reason baiting is more successful is that the percentage of Pharaoh ants typically out foraging at any given time is around (a) 5%. That means the best shot we have at control is to use the foraging ants to take poison bait back to the nest.

6. In severe infestations of larger buildings, like warehouses and hospitals, it could take (c) up to a year before total elimination is achieved. 

7. A mature Pharaoh ant colony can house (d) up to 300,000 ants. That's a lot of ants. A single queen can produce many hundreds of workers in just a few months. And remember, the colonies of Pharaoh ants often house multiple queens. Unlike many other ants, they breed continuously throughout the year in heated buildings.

Now that you know more about these difficult pests, be aware of the ants around you and be sure to report any suspected infestations of Pharaoh ants before they take over!

Tuesday's Quiz: Pharaoh Ants

Today's quiz takes a closer look at a rare but difficult variety of ant: the Pharaoh ant. Although most ants infesting San Diego neighborhoods are Argentine ants, we recently identified a colony of Pharaoh ants living in an apartment complex. Here are a few questions to test your knowledge of these tiny invaders.

1. Pharaoh ants are polygynous. What does this mean in the ant world?

a. Worker ants carry both reproductive parts.

b. Colonies have many queens.

c. Queens lay many eggs and then die.

d. Only queens have wings.

2. Pharaoh ants can be identified by

a. their dark, black color.

b. their distinctive odor when squashed.

c. a distinct club at the end of their antennae.

d. a turban-like appendage from which they get their name.

3. Pharaoh ants are often associated with infestations in

a. hospitals

b. apartments

c. hotels

d. grocery stores

4. The best way to treat Pharaoh ants is to

a. spray and bait

b. spray only

c. bait only

d. call a pest professional

5. What percentage of a Pharaoh ant's nest is typically out foraging at one time?

a. 5%

b. 20%

c. 50%

d. 75%

6. In severe infestations of larger buildings, how long might total elimination take?

a. 2-4 weeks

b. 2-4 months

c. up to a year

d. 2-4 years

7. Pharaoh ant colonies are large and very mobile. How many ants might one colony contain?

a. up to 1,000 ants

b. 2,000-5,000 ants

c. 50,000-80,000 ants

d. up to 300,000 ants

For answers to today's quiz, click here.

Fire Ants

As noted in a previous post, Argentine ants are the most common  household pests in San Diego County. However, there are about 200 different ant species in California, including the southern fire ant (Solenopsis xyloni) and the red imported fire ant (Solenopsis invicta). A recent article in the Riverside Press-Enterprise discussed an infestation of fire ants in Rialto, where these pests have been devouring crops and threatening residents for the last 10 years. Fire ants came to the United States on cargo ships from South America in the 1930's. Today they are a problem that has cost millions in dollars per year, especially in Riverside and Orange counties. The battle against fire ants got tougher after funding for a statewide eradication program was cut in 2003. All of Orange County and parts of Riverside and Los Angeles counties are under a red ant quarantine, limiting the movement of plants and soil in those counties.

Fire ants vary in size, ranging from 1/16 to 1/4 of an inch long, and are yellow to dark red-brown. They have a stinger at the tip of the abdomen. Colonies range in size from 80,000 to 250,000 workers in a single-queen colony. Queens can produce approximately 1,500 eggs per day. They are called "Fire Ants" because of the fiery, painful sting they inflict. The venom on these tiny ants causes painful, itchy welts or blisters. For individuals who are allergic, the bites can be fatal.

Because their nests are so large, sometimes several treatments of insecticide are needed to reduce or eradicate the colony. Baits which contain an insect growth regulator (IGR) and/or a slow stomach poison can also be effective. Here in San Diego, we don't see many infestations of fire ants - but with populations growing nearby, we want to offer suggestions to homeowners that apply to control of all varieties of ants. Here are the basics:

1. Determine what the ants are attracted to and remove the source.

2. Vacuum trails, clean with soapy water or spray with window cleaner.

3. Locate entry points and fill with caulking or petroleum jelly.

4. Place ant bait stations or gel bait labeled for ant control near the entry points.

5. Continue to clean up trails, as baits require time to work.

6. If ant invasions continue, call your pest professional.

Quiz Answers

Yesterday's quiz generated some good discussion about ants. Here are the answers to the quiz, with a few explanations.

1. Ants are close relatives of (c) bees and wasps. If  you said (d) aphids, you probably remember that there is a connection between ants and aphids, and there is. Ants are attracted by the "honeydew" aphids leave on plants - so they actually protect and care for aphids outdoors. But bees and wasps are the ants' close relatives, belonging to the insect order Hymenoptera.

2. According to San Diego County's website on ants, there are about (b) 200 species of ants in California. The website also states there are fewer than a dozen that are important. We are not sure how that makes the others feel. Among the most common are the Argentine ant, pharaoh ant, odorous house ant, thief ant, and the southern fire ant. To see pictures of each of these for purposes of identification, click here and scroll down.

3. Ant baits attract ants, inviting them to feed on poisonous bait and take it back to their nest. From a recent article on ant baits in PCT Magazine, we learn that the process whereby foraging ants bring food to those back in the colony is called trophallaxis. Workers collect fluids that are stored in the upper part of their digestive system, then regurgitate a portion of the stored food and pass it on to other workers, larvae, and queens. In fact, in some species, there are workers who remain in the nest, with the specific job of storing the fluid so it will be available in times of food shortage. This is the long way of saying the correct answer is (d) - ants eat the bait, then regurgitate it to feed ants back at the nest.

4. The chemical substance ants leave behind in a trail for others in the colony to follow is (a) a pheromone trail. The pheromones ants excrete are hydrocarbons that trigger a response to follow the path to food. Most ants renew the pheromones as long as the food is available. In some species, the ants actually mark trails that no longer lead to food with a repellent pheromone. Cleaning up an ant trail with a household cleaner can actually erase the pheromones and confuse the ants. But if the food remains, they'll be back!

5. Most ants we see walking around are (a) searching for a food source. Ants are always on a mission. The ones we see in our yards and homes are focused on foraging for food and getting it back to the colony. They do not need wi-fi, and have their own GPS.

6. This is a trick question. Give yourself credit for (a), since the ant queen is fed by the other ants. But the best answer is (c) - the queen is more like a slave or a prisoner. She doesn't order the other ants around, and is limited to her egg-laying role in the colony. Not a very glamorous life.

7. The best way to tell if you have Odorous house ants is to (d) squish one and take a whiff.  The identifying smell has been described as "rotten coconut." They are tiny, around 3mm in length, dark brown to black in color. Odorous house ants prefer sugary foods and fruits and usually forage in large numbers. These ants are less common than Argentine ants in San Diego, but now you know how to recognize one if you see one.

How did you do? Look for another bug quiz in next Tuesday's blog.

Tuesday's Quiz: Test Your Ant IQ

We here at Centurion Pest Control think the more people know about bugs, the fewer they'll have to deal with. Hence, a new weekly feature on the blog: Tuesday's Quiz. Each Tuesday we'll test your Ento-IQ, with the answers to the quiz available in Wednesday's blog. You could probably Google the answers in about 5 minutes, but where's the fun in that? Instead, use the 24 hours between questions and answers to think through the questions logically and see how you do the next day. Or maybe use the quiz as a family activity, so everyone in the household gains a little more information about the bugs that bug us. Hopefully, as you learn more about the habits of these pesky invaders, it will help keep them out of your home and back in the wild where they belong.

Since yesterday's blog was on ants, the quiz today will stretch your knowledge of the characteristics of ants. Have fun!

1. Ants are close relatives of which of these bugs:

a. fleas and ticks?

b. mosquitoes?

c. bees and wasps?

d. aphids?

2. About how many species of ants are there in California?

a. 20

b. 200

c. 50

d. 500

3. Ant baits attract ants, inviting them to feed on poisonous bait and take it back to their nest. How do the ants take the bait to their colony?

a. Small particles of bait adhere to their legs and antennae, then transfer to other ants.

b. Foraging ants carry pieces of bait, often bigger than the ants themselves, back to the nest.

c. Like an ant STD, poisonous bait is transfered during mating.

d. Ants eat the bait, then regurgitate it to feed ants back at the nest.

4. Some ants leave a trail for others to follow. What is the name of the substance they leave behind?

a. Pheromone Trail

b. Honeydew Trail

c. Lipid Trail

d. Sweat Trail

5. What are ants most likely doing when they are walking around?

a. searching for a food source

b. searching for a mate

c. searching for their colony

d. searching for wi-fi

6. The "Queen" of the ant colony is...

a. waited on by the other ants, who bring her food.

b. distinguished by a crown-like appendage on the head.

c. more like a slave or prisoner than a queen.

d. too small to be seen by the human eye.

7. The best way to tell if you have Odorous House Ants is to...

a. smell the trail they leave.

b. put out foul-smelling bait.

c. look for an exceptionally large thorax.

d. squish one to find out if it smells bad.

Find answers to the quiz in tomorrow's blog.

Ants Again

Do you have ants again? Although we've blogged about ants here before, they are such a common problem in San Diego we thought they deserved another look. Among the several varieties of ants in Southern California, Argentine ants are by far the most numerous. First, a little background.

Argentine ants were brought to the United States from Brazil in coffee shipments in the late 1890's. They are prolific breeders, so they quickly established nests across the southern states. They are also relatively aggressive among other insects, very effective in outnumbering and overtaking other varieties of ants. They are survivors! Around  your  home, you may have multiple colonies containing easily a million or more individual ants. Because all Argentine ants in this country came from the same colonies originally found in New Orleans, they can recognize each other and team up to form super-colonies, causing problems for home owners as they invade in search of food and water.

This tiny terrors can be stirred up by changes in weather. When we experience draught conditions, they may be in the house looking for water. When it rains, their nest may have been disturbed. Or perhaps you just left a crumb on the counter that was particularly attractive. Ants send "scouts" out looking for food. The scouts then make a trail from the nest to the food source - and all the ant cousins follow. Knowing this can help you break the trail and send the ants back outside. Empty trash containers in the house often, use food containers with tight lids, keep pet dishes clean, and follow any trails that may appear until you find the point of entry into the house. Some household detergents or window-cleaning sprays will help erase the scent scouts leave for others to follow. But if you use indoor bait stations, be sure  you do not spray detergents or chemicals near the bait, or ants will refuse it. Inspect caulk around sinks and windows, repairing any breaches. 

It is impractical to try to eliminate all ants outdoors, but some precautions can help keep them out of  your house. Outside, it is a good idea to check for cracks and crevices around the foundations where ants might enter. Caulk here too, as well as around places where pipes or wires enter the house. Avoid planting fruit trees too close to the house, and keep grass and mulch at least a few inches from foundations. Trim tree branches and vines away from the roof. Eliminate standing water and do not keep wood piles next to the house. Ant stakes may be useful as baits outdoors. If you have been diligent in trying to keep the ants out and feel you are losing the battle -  you are not alone! San Diego homeowners fight ants year 'round, but especially in summer months. If  you can't solve the problem yourself, call in a professional. New products help pest control companies do a better job in stemming the tide of these aggressive and populous pests. To watch a time-lapse video of ants tunneling  in an ant farm, click here.

Argentine Ants

Summertime in San Diego means ants are on the move. The most common ant in our area is the Argentine ant, scientific name linepithema humile. Argentine worker ants are 1/16-inch long and light to dark brown. The queens are 1/8 to 1/4 inch long and covered with fine hair. Males are slightly smaller and shiny brown-black. Colonies consist of several hundred to thousands of workers and several queens. They are found throughout the southern United States and California, typically living in nests outdoors and near food sources. They become major pests when they come indoors seeking food or water. The most effective control is accomplished when ant trails are followed to nests and treated with a residual insecticide.

We see infestations of Argentine ants year-round in San Diego, but in the summer they are especially aggressive. The San Diego County Department of Agriculture has good information for homeowners regarding the identification of ant varieties and ant management on their website.