The Seasonal Natural History of the Ant,Dolichoderus mariae, in Northern Florida

Abstract

Dolichoderus mariae Forel, (Hymenoptera: Formicidae) is an uncommon, monomorphic but locally abundant, reddish-brown ant of peculiar nesting habits, whose range includes most of the eastern USA. In north Florida the ant excavates soil under wiregrass clumps or other plants with fibrous roots to form a single, large, shallow, conical or ovoid chamber broadly open to the surface around the plant base. Colonies are highly polygyne and, during the warm season, inhabit multiple nests connected only by above ground trails, over which nests exchange workers. Although monomorphic, worker size may differ significantly between colonies. The colony cycle is dominated by strong seasonal polydomy. From one or two over-wintering nests, the colonies expanded to occupy up to 60 nests by late summer, then retract once more to one or two nests by mid-winter. The worker-to-queen ratio changed greatly during this cycle, with over two thousand workers per queen during fall and winter, dropping to a low of about 300 during midsummer. Most of these summer queens probably die during the fall. Colonies reoccupy roughly the same area year to year even though they contract down to one or two nests in winter. Observation of fights in the contact zone between colonies suggested that the colonies are territorial. The ants subsist by tending aphids and scale insects for honeydew and scavenging for dead insects within their territories.

The architecture of subterranean ant nests: beauty and mystery underfoot

“…Dolichoderus mariae appears to have abandoned all pretenses of aesthetics and simply excavates the soil under grass clumps to form a large, irregular cavity exposing the grass roots that the colony then uses as a scaffold on which to hang itself and its brood (Fig. 12) (Laskis and Tschinkel 2009). …”

“…Figure 15 shows nests built by approximately 6000 Monomorium viridum, a very small ant, 6000 Pheidole morrisi, a medium-sized ant, and P. Fig. 12 The polygyne, polydomous ant Dolichoderus mariae simply excavates the soil beneath grass clumps and uses the exposed roots as a scaffolding on which to hang the workers and brood (Laskis and Tschinkel 2009) badius, a large ant. Larger ants need larger diameter shafts and higher chamber ceilings than do smaller ones.…”

A seasonal natural history of the ant, Odontomachus brunneus

“…For social insects such as ants, it is the life history of the superorganism that is of interest-the individual colony members are the parts that make up the superorganism. Natural history studies may include, but are not limited to the seasonal cycle, colony size, queen number, number of nests per colony, worker size, alate size and number, nest location, and nest architecture (Hölldobler and Wilson, 1990;Gadgil and Bossert, 1970;Tschinkel, 1991Tschinkel, , 1993Laskis and Tschinkel, 2009).…”

The response of an aphid tending ant to artificial extra-floral nectaries on different host plants

“…The feeding activities of ants sometimes change following the seasons, in particular following the natural growth of their colony and brood rearing, which increases the need for protein sources while, during other seasons, carbohydrates are a priority. Seasonal differences in feeding strategies were found in some ant species (Laskis and Tschinkel 2008) but not in others (Barbani 2003).…”