According to Betteridge’s law of headlines, the answer should be no. Feeding your ants a high-protein diet seems like a great idea in order to increase your colony’s growth rate. After all, queens need protein to produce eggs and larvae need protein to grow. So more protein equals a larger colony, right?
According to this study by Dussutour and Simpson (2012), the above mentioned equation is not true at all. The researchers have used Lasius niger in their study. First, the effect of protein-to-carbohydrate ratio was determined, resulting in a reduced survival with a high-protein diet. Further experiments showed that the increased mortality was due to the increased protein intake rather than the decreased carbohydrate intake. The researcher conclude that a high-protein diet not only decreases the worker lifespan, but also reduces colony size.
So for optimal colony growth, what ratio should you feed your ants? The study showed that with a 1:5 (protein-to-carbohydrate) ratio, ants lived longest. However, lower protein diets were not included in the study. It is therefore hard to tell if you should feed your ants even less protein, but for Lasius niger you should probably not exceed the protein-to-carbohydrate ratio of 1:5.
An important sidenote to this study is that it was performed on worker ants without any brood, meaning they weren’t able to regurgitate the protein in order to transfer it to larvae. In a colony, most of the protein would not be digested by the worker ant like in this study. Further research is therefore needed to determine the effects of diet on colonies.
Implementing the results of this study for the ant keeping hobby, I would suggest that synthetic foods (such as honeydew surrogate), which force the ants a fixed intake of nutrients, should be prepared with a bit of care. Increasing the amino acid concentration in the honeydew surrogate recipe for example, would probably be a bad idea for most ant species. You should stick with the original recipe. When providing protein and carbohydrates in seperate sources, you shouldn’t worry too much though.
In the Netherlands, many ant keepers feed their ants something called “honeydew surrogate”. It’s a homemade golden liquid of which the composition is designed to imitate the honeydew secreted by aphids. In nature, honeydew is the main source of nutrients for many ant species. Homemade honeydew surrogate contains sugars, amino acids and vitamins, in concentrations that are almost identical to that of natural honeydew. However, its amino acid content is ten times higher than that of natural honeydew. This is done on purpose, because in nature, ants have to travel much longer distances to gather honeydew than in captivity, using up a significant part of the sugars and therefore concentrating the amino acids in honeydew before reaching their nests.
Many ant species seem te love honeydew surrogate. I feed it to my ants and when I’m short of insects to feed them, the amino acids in honeydew surrogate are an excellent replacement for insect protein. However, I like to add insects to my ants’ diet, just to make sure they get enough protein. Honeydew surrogate is easy and cheap to make and the batch will last for quite a time, depending on the number of colonies you have and their sizes.
I guess you’re dying to know how to make honeydew surrogate for your ants. I’ve translated the Dutch recipe for honeydew surrogate that can be found here on AntForum.nl (page is in Dutch). All credits go to user Mika, the inventor of honeydew surrogate, and to user Floris, who took the time and effort to share the recipe. My purpose is to make it accessible for other countries as well.
Honeydew surrogate recipe
25 ml of liquid amino acids (also known as BCAA) *
50 ml of maple syrup, honey is fine too
130 grams of glucose (also known as dextrose or grape sugar), table sugar is fine too
480 ml of water
You will also need:
Stirrer (e.g. spoon)
Syringes (no needle required)
* You might wonder where to get liquid amino acids. Liquid amino acids are sold in (online) sport supplement stores. The supplement serves as a quick and easy source of amino acids for bodybuilders. Try to look for liquid amino acids in ampoules, because you will only need one ampoule. They often come in packs of 10, 20 or 30, so although one ampoule isn’t expensive at all, the whole pack will be expensive while you won’t need all ampoules. Try to share the ampoules with other ant keepers and split the costs, or try to get your hands on one ampoule from a bodybuilder or a nearby gym.
Time to make the honeydew surrogate. Dissolve the glucose in the water in a large container. Stir or heat to increase the dissolution rate. Now add the maple syrup and stir. Finally, add the liquid amino acids and stir. Your honeydew surrogate is done! This recipe yields about 650 ml honeydew surrogate.
Honeydew surrogate is prone to spoiling, so it must be freezed prior to storing. I always fill a few syringes with the solution and then I freeze these. I store the remaining batch in a large bottle and freeze that too. When I need to feed my ants, I thaw a syringe by placing it at room temperature for about an hour. When all syringes are empty, I thaw the large bottle with the honeydew surrogate batch and refill my syringes after cleaning them thoroughly. Using this method, the batch lasts for months. Bon appétit.
Ants that do not live in tropic regions need to pass the harsh winter by means of dormancy or inactivity, in order to survive the extreme temperatures and the occurring food shortage. Dormancy is a state in which the ant’s development is temporarily interrupted. Metabolic activity is reduced to conserve energy and brood is paused being raised.
Dormancy has many forms, depending on the species and habitat of the ants. A simple resting state is called quiescence and is opposed by diapause. Diapause is an extreme form of dormancy, which is initiated and inhibited by specific conditions, like temperature and photoperiod. However, not only environmental conditions can contribute to the onset of dormancy. Temperate ants also possess a biological timer, which, in these species, is of greater importance for controlling their cycle than environmental factors.
So what does this mean for the ant keeper? Should we worry about the dormancy of our precious ants? I believe we should, depending on the species. In most tropical species, eggs, all larval stages and pupae are present throughout the year. They don’t need dormancy and can therefore be kept at high temperatures all year. My Polyrhachis dives colony for example, doesn’t need dormancy. I can enjoy them all year long.
However, temperate species do, to some extent, need dormancy. Species from the southern part of the temperate regions do not possess the biological timer controlling their cycle. Their dormancy is initiated by a drop in temperature. When there is no drop in temperature, they keep developing. Skipping the dormancy has no negative influence on egg-laying and development of larvae. I, however, do recommend dropping the temperature in the winter for 6 to 12 weeks in order to initiate dormancy. For my Messor structor colony, I will start dormancy in December and the temperature will vary between 10 and 15 °C (50-59 °F).
More important is to respect the dormancy of northern temperate species. My Lasius flavus, Lasius fuliginosus, Lasius niger, Formica fusca and Myrmica rubra colonies are in dormant state since early November and will stay so until late March. These species have a biological timer, so even if you do not drop the temperature, the development of brood will cease. It is still very important to drop the temperature though, because these ants need something called ‘cold reactivation’. They are supposed to be exposed to low temperatures in order to restore their brood-rearing-ability, which depends on many factors. Without cold reactivation, the colony will eventually fail to grow. Your colony needs to be refreshed, upon which you can enjoy a nice growth in spring!
So how do I drop temperatures for my ants? I refrigerate them. The temperature in the refrigerator is about 5-10 °C (41-50 °F), which is cool enough for cold reactivation. If you do not have a refrigerator available for ants, you can also put them in a cold basement or you can come up with another solution. Just do keep in mind that the temperature should never drop below freezing point, which can kill your ants. The ants do not need to be fed during dormancy, but water should always be available.
Below my colonies in the refrigerator can be seen. It is a second-hand refrigerator, stored in the basement. Nothing fancy, it is the cheapest second-hand refrigerator I could find (and it’s surprisingly clean for that matter). As long as it cools, it will suffice.
After dormancy, temperatures should rise steadily, so the metabolic activity can increase slowly. Try to move the ants to a cold room before actually exposing them to high temperatures. Instant warming up of the ants can kill them. Because I have a special refrigerator for my ants without any food being stored in there, I can just raise the temperature in the refrigerator steadily.
Ant dormancy is a subject which is easily ignored in literature. It is, however, not exactly an unimportant aspect of ant keeping. It determines the success of a colony by influencing its growth. As an ant keeper, you should therefore, if required, respect it and let your hard-working ants relish their well-earned rest.