Food, Paper, and Sand

 Feeding ~600 mole rats is quite a feat. In the wild they mainly eat underground tubers and bulbs. In the lab, they are fed a diet of sweet potatoes and english cucumbers, that we buy in bulk. When the colonies began, several types of food were tested, and these two were the winners in popularity and nutrition.

Deliveries are about every two weeks, and in a month we can go through about 560kg (1234lb) of sweet potatoes and 400 English cucumbers (The long ones). The food is stored in fridges, although recent mechanical have led to large amounts of food loss because the food freezes, thaws, and goes rotten. We are trying out different ways to store the food, but even potatoes left out of the fridge and in the dark got moldy.

The two other basic necessities for mole rat life in a tunnel system include paper and sand. We get massive rolls of thin paper (like really cheap paper towels) which we provide to the mole rats to use for nest building. They have plastic shoe boxes attached to certain points in the tunnel systems, which are used as food stores, latrines, or nests. The nest boxes are quickly obvious because they are often full of paper and you cannot see inside.

The sand is probably the most labor intensive part and needed in the largest amount. The sand is brought to the lab from various dunes on the reserve, and must be completely dry. Each day the feeder tubes (upright tubes on the systems) are filled with sand to resemble collapses and encourage working behaviors and food searching behaviors. The feeders are filled once in the morning and once in the evening for most colonies.

However, during twelve hour scans we fill the tubes every two hours, so that there is plenty for the mole rats to do during the scan. We also try to fill them before doing focal observations, if there is not enough sand already in the tunnels.

You may be thinking, where does all this sand go? What do the mole rats do with it?

At one end of each tunnel system, there is a large box we call the wastebox. It is where the mole rats put things they don’t want in the colony. This includes excess sand, old nesting paper, and food that they don’t want. But, since these systems aren’t completely accurate at resembling real life, sometimes the wastebox becomes a food store, or even a nest.

When the wastebox gets full, the sand is removed. Also sand is removed when the rooms and colonies are deep cleaned. All this sand is full of paper and old pieces of food, which must be removed before it can be put out in the reserve. The workers use large metal sifters to remove the large pieces of debris, so we aren’t adding paper to the environment or feeding the wildlife. The sand needs to be taken out often not only because of the amount, but it also helps keep the colonies clean.

At the end of each day all the volunteers/researchers in the lab (currently 6 of us) do room checks. This involves checking to make sure each colony has food, and filling the feeders. The feeders definitely take the most time.