A friend is building a new house and he wanted to know about the ant colonies he found in his yard.
These shiny black ants are Messor pergandei (also seen in the literature as Veromessor.) They are a type of harvester ant, which means they collect, process, and store seeds as their main food source (See previous post).
Nearby was another ant colony.
Although these ants look similar superficially to those above, on closer inspection their bodies are dark maroon-red rather than black, particularly in the mid section. They also have fine parallel grooves on their heads. Theses ants are harvesters known as Pogonomyrmex rugosus.
Although both these species harvest similar types of seeds, it is not uncommon to find them living near each other. Robert Johnson (1992) suggests that they may segregate over broad regions based on soil texture, but coexist together in regions of overlap.
Some of Bill's earlier photographs showed the ants had placed a ring of wood fragments from construction as a barrier around their colony. It would be interesting to see whether they were reacting to conspecific colonies or those of other species.
Wouldn't it be cool to have ant neighbors like these?
For more information:
Kwapich, C.L., Gadau, J. & Hölldobler, B. (2017) The ecological and genetic basis of annual worker production in the desert seed harvesting ant, Veromessor pergandei.
Behav Ecol Sociobiol 71: 110. https://doi.org/10.1007/s00265-017-2333-1 (link)
Johnson, R.A. (1992) Soil texture as an influence on the distribution of the desert seed-harvester ants Pogonomyrmex rugosus and Messor pergandei
Oecologia 89: 118. https://doi.org/10.1007/BF00319023 (link)
Johnson, Robert A. 1991. Learning, Memory, and Foraging Efficiency in Two Species of Desert Seed-Harvester Ants. Ecology 72: 1408- 1419. (link)
Rissing, S.W. (1988) Dietary similarity and foraging range of two seed-harvester ants during resource fluctuations. Oecologia 75: 362. https://doi.org/10.1007/BF00376938 (link)