Todies are most active on sunny mornings after rain, with activity peaks occurring during March and September (Raffaele 1989). Breeding activity is greatest from February to April, during the dry season, as todies court, build nests, and delineate breeding territories (Kepler 1972).
Many coraciiformes roost huddled in groups or in cavities to conserve energy required for thermoregulation, but Puerto Rican Tody roosts singly in trees (Kepler 1972, Merola-Zwartjes and Ligon 2000). Females, but not males, sometimes enter torpor when ambient air temperatures are low (Merola-Zwartjes and Ligon 2000). The basal metabolic rate of Puerto Rican Tody varies throughout the year, and their body temperatures are consistently lower than expected for their mass (Oniki 1975, Merola-Zwartjes and Ligon 2000).
Kepler (1972) observed various behaviors of Puerto Rican Tody. Puerto Rican Tody bathes in flight in drizzling rain, dew, or wet foliage. They scratch and preen. Todies clean their bill by rapidly stroking the bill base-to-tip against a perch, swiping it on the branch one to four times per side after foraging, regurgitation, cleaning their bodies, or during nest excavation. Todies defecate while perched, and do not defecate in their nest burrows. They also commonly regurgitate to expel indigestible matter, followed by keeping their bill open and gaping. They have not been observed drinking, and likely obtain water from leaves and insects while feeding. Todies ruffle their feathers and shake laterally, then relax and allow the feathers to settle during preening and bathing, feeding, burrowing, displaying to threaten opponents, and by females showing submission. Todies engage in short flights averaging 1.3 meters (n = 3472 observations) with a maximum flight of 16 meters, and rarely hover. Todies seldom are observed on the ground, and hop rather than walk on the ground. Todies also flick their wings rapidly and repeatedly, usually during preening, bathing, or active feeding periods. Although some birds use a "favorite perch" for foraging and roosting, the tody seems to only use a favorite perch before entering the nest.
Territories are small and defended by the pair year-round (Waide 1996, Harris 2009). Home ranges are larger than breeding territories, which are centered around the nest burrow; pairs forage beyond their breeding territory boundaries when neighboring todies are not nearby (Kepler 1972). Territory sizes are generally 0.6 to 1.2 hectares (mean 0.7 hectares) in El Verde, and 1.5 to 4.0 hectares in and around Mt. Britton (Kepler 1972). Territories are largest in flat and open expanses of forest and in ravines with boulders, and todies avoid territories with large rocky rivers possibly due to the lack of nesting banks (Kepler 1972). The territory area defended increases at higher elevations, although the volume of area defended, when canopy height is included as a third dimension, is similar to lower elevations (Kepler 1972). Pairs in smaller territories defend more aggressively than pairs in larger territories (Kepler 1972).
Kepler (1972) observed 12 agonistic displays in Puerto Rican Tody territory defense. Close disturbances and potential predators cause the tody to rapidly bob up and down, accompanied by several vocalizations. Males bob more frequently than females during territory defense, but both sexes sometimes bob silently after landing from feeding or during nest-excavation. Todies fluff and raise their crests at intruders. Todies chase intruders, sometimes accompanied by a wing-rattle, and replace the intruder by assuming its position on the perch. Wing rattles occur most commonly during territorial defense (Kepler 1972, Harris 2009), and wing flicking occurs in both territorial defense and sexual displays. Sometimes the tody leans forward and fluffs its feathers, holding its bill horizontally and periodically raising its crest while staring intently at the intruder. The intruder may perch with feathers fluffed, and twist its head to face away from the aggressor as a sign of submission. If agonistic behavior is intense, todies chase one another over long distances with irregular flight patterns, and sometimes grab each other and tumble downward or fly as a unit. Rarely, two rivals land on one branch, with one hanging upside-down and the other perched adjacent to it, both with straight unruffled bodies and vertically pointed bills. After several seconds, the upside-down bird fluffs, returns to an upright posture, and they return to normal agonistic behaviors. Todies also rarely fence with their bills and push each other with their bodies. Vocalizations include a loud beep, a bee-beep, a beep followed by a trill, and accelerated normal beeps (see Vocalizations).
Todies are monogamous and have single broods (Harris 2009). Courtship occurs within the breeding territory, and pairs usually limit courtship activities to within 5 m of the nest site and 3 m of the forest floor (Kepler 1972). Most courtship is concentrated during nest-building and egg-laying, from February to May (Kepler 1972). Males and females chase each other during courtship for short distances, accompanied by wing-rattles. A female may periodically flick her wings after being chased, and enter a submissive posture with breast low, wings open, feathers fluffed, and tail lifted upward (Kepler 1972). Males and females also have a "flank" display preceding copulation, where both birds fluff out their flanks to the point that they are a nearly spherical ball of feathers (Harris 2009). Mates sometimes bring prey items to each other as well, usually during incubation, care for young, or after nestlings have been killed (Kepler 1972). Courtship vocalizations appear agitated, and include a low and muffled beep, a bee-beep, a normal or accelerated beep call, a beep followed by a trill, or a loud beep call (Kepler 1972; see Vocalizations).
Social and interspecific behavior
Todies usually are found singly or in pairs (Harris 2009). They retain year-round pairs, loosely bonded during the non-breeding season, within roughly the same home ranges (Kepler 1972). They are not a social species, and do not flock or nest socially (Kepler 1972). On average, 70% of todies are paired during the breeding season (Kepler 1972).
Predators likely include Sharp-shinned Hawk (Accipiter striatus), Red-tailed Hawk (Buteo jamaicensis), Barn Owl (Tyto alba), Pearly-eyed Thrasher (Margarops fuscatus), and Indian mongooses (Herpestes mungo, Mustelidae) (Waide 1996). Additionally, adult Diptera and nematodes likely feed on Puerto Rican Tody (Waide, 1996). Mongooses prey on Puerto Rican Tody and its nestlings, especially if nest burrows are below 0.8 m above the ground (Kepler 1972). Several animal species may cause a nesting pair of todies to abandon their nest, even if the animal does not harm the eggs, including frogs, lizards, scorpions, stinging ants, snakes, whipscorpions, snake-like lizards, and tarantulas (Kepler 1972).
Fremgen, A. (2018). Puerto Rican Tody (Todus mexicanus), version 2.0. In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/nb.purtod1.02