Experimental treatments and survival of transplanted harvester ant colonies

In sessile organisms such as plants and benthic invertebrates, founding
propagules typically suffer extremely high rates of mortality due to both
extrinsic and intrinsic factors.  Many social insect species
share similarities with these groups, but factors influencing early colony
survival are relatively unstudied.   We used a field experiment
to measure the importance of environmental quality relative to intrinsic
colony properties in the harvester ant, Pogonomyrmex occidentalis, by
monitoring the survival of 584 experimental colonies. Colony survival was
primarily determined by intrinsic factors. Multiple mating by the
queen and larger colony size at the time of transplant increased survival,
but queen size, maternal lineage and the composition of plant species in
the vicinity of the colony did not. Food supplementation increased
survival significantly when natural food was scarce, but was not
consistently beneficial, in contrast to predictions.  Our results
emphasize the general importance of rapid growth and early attainment of
large size in the survival of sessile species. However, attributes
specific to ants, their sociality and mating system, also strongly
affected survival. Colonies with multiply-mated queens were more likely to
survive over a wide range of circumstances, highlighting the importance of
this trait even at the early stages of colony life. These are data to
support the paper "The benefits of being big and diverse: early
colony survival in harvester ants." The data are the
experimental traits of the colonies used for transplantation (size and
lineage of the queen, size of the colony, mating status, food treatment,
local vegetation), the characteristics of the transplant itself (year of
transplant and the transplant set) as well as the experimental results
(the duration of survival and whether the colony survived until the end of
the experiment).