Termites are destructive pests whose presence often goes unnoticed until the damage is already done. The sudden, mass emergence of winged insects, commonly called “hatching,” is actually a swarming flight. This swarming is a reproductive effort where mature colonies release specialized, winged adults called alates to disperse and establish new colonies. Hundreds or even thousands of these swarmers take flight simultaneously, typically occurring only once a year. The appearance of a swarm is the most visible indication that an established termite colony is already active inside or very near a structure.
Environmental Triggers for Termite Swarming
The moment a termite colony releases its swarmers is precisely timed by environmental conditions that maximize the chance of new colony survival. For the most common species, subterranean termites, swarming is primarily triggered by a combination of warming temperatures and high moisture levels. This synchronized flight most often occurs during the spring and early summer months, particularly following a significant rainfall event. The moist soil is necessary for new kings and queens to burrow and begin laying eggs.
Consistent daytime temperatures reaching around 70°F or higher often signal the beginning of the swarming season for subterranean species. The high humidity that accompanies the warmth and rain is also beneficial, as it helps prevent the swarmers’ delicate exoskeletons from quickly drying out. Swarms generally happen during the day, often between mid-morning and early afternoon, when light and temperature conditions are optimal for flight.
The timing varies significantly by species and geographic location. Drywood termites, for instance, typically swarm later in the year, generally from late summer into the fall, and may swarm in the evening or at night. In consistently warm climates, swarming activity can occur throughout the year, but the primary environmental cues of warmth and moisture remain the dominant factors.
Identifying the Reproductive Termites
The winged reproductive termites, or alates, are frequently mistaken for flying ants, which also swarm seasonally. Distinguishing between the two is simple by observing three key physical characteristics.
Termite swarmers have straight, bead-like antennae, whereas flying ants have distinctly elbowed or bent antennae. Termites have a broad waist, giving their body a uniform thickness from head to abdomen. In contrast, flying ants possess a constricted, pinched waist that clearly separates the thorax and abdomen into three distinct segments.
The most definitive difference lies in the wings. Termites have two pairs of wings that are nearly equal in size and length, often extending well past the abdomen. Flying ants also have two pairs of wings, but their front wings are noticeably longer than their hind wings. Finding small piles of discarded wings, all of the same size, near windows or light fixtures is a strong secondary sign of a termite swarm.
What Happens After the Swarm
The single purpose of the swarm is reproduction and the expansion of the species. Once the alates emerge, they take a brief, weak flight, pairing off with a mate shortly after leaving the parental colony. The male and female pair then land and intentionally shed their wings by breaking them off at a pre-determined suture line, an act known as dealation. This physical sign of discarded wings is often the first evidence a homeowner finds.
The now wingless pair becomes the new king and queen, and they begin a tandem search for a suitable nesting site, with the female leading the male in a behavior called a tarsal walk. They seek a source of wood and soil to establish a small chamber where the queen will begin laying her first clutch of eggs. The presence of swarmers indoors almost always indicates that a mature, wood-consuming colony is already hidden within the structure. Killing the swarmers only removes the visible symptom; the true problem remains with the workers that continue to feed on the wood of the structure.