Industrious as an ant!

Posted on 02 April 2015.

According to a study published in the journal Global Change Biology, New York ants can swallow the equivalent of 60,000 hot dogs in one year.

The study shows the importance of planners really understanding and managing urban ecosystems.

They are found just about everywhere in the world: in tropical forests, desert steppes, the African savannah, and of course in our gardens. They contribute to the balance of natural ecosystems, in particular through their role as decomposers (in other words, they clean up the environment!). But did you know that ants are also very helpful in our cities?

Dr. Elsa Youngsteadt and her team conducted an interesting study on the food consumption of New York arthropods – such as ants, centipedes, spiders and other invertebrates. Spreading scraps of junk food around streets and parks in the Big Apple produced some surprising results. Firstly insects are voracious. Extremely voracious! "We estimate that in the street medians of Broadway and West Street, arthropods consume between 600 and 975 kg of food per year - the equivalent of 60,000 hot dogs, 200,000 cookies or 600,000 potato chips.” Since we know New Yorkers produce more than 40,000 tons of waste per day, the insects’ contribution to reducing it is modest, but significant. Researchers made a second observation: insects found on sidewalks ingest two to three times more garbage than those living in parks, where there is greater biodiversity. Why? Because the pavement ant (Tetramorium caespitum), which is the most common ant in New York and in Europe, is very efficient at cleaning up organic waste in urban areas. And lastly, ants eat almost as much as rats. Waste devoured by ants leaves less waste for rats and so there are fewer rats.

Although Dr. Elsa Youngsteadt’s study highlights the ecological services provided by arthropods, it especially shows how important it is for planners to really understand and manage urban ecosystems. A city that takes care of its six-legged citizens will have less waste and fewer rats - which come with a number of health problems. It is certainly something worth exploring, given the great and unexpected diversity of all these little critters working for our good in the shadow of our skyscrapers.