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Vocal interactions are common in chorusing frogs. Changes in the calling patterns of Eleutherodactylus johnstonei males were analyzed by recording their responses to playbacks of conspecific calls repeated at fixed periods (long: 1.7 s, short: 0.98 s). The call period and timing, estimated through the onset response time, were determined for each male. Males reduced and regularized the period of their calls in response to both stimuli, regardless of their absolute and relative period (i.e., the difference between the male’s period and the stimulus period). Males avoided initiating their calls during ongoing stimuli, but did not time their calls in the silent gap between successive stimuli in ways that reduced the probability of overlap: the proportion of calls without overlap did not depart from random expectations when the silent gap was long, and was smaller than expected when the gap was short. This result indicated that males react to the presence of the virtual competitor but not to its particular characteristics. Fixed responses have been described in other anurans, and often relate to trade‐offs between female attraction, male competition, predator attraction, and depletion of energy reserves. Lack of coordination with the stimuli, beyond inhibition of calling during an ongoing stimulus, also indicates somewhat rigid vocal strategies, at least under the experimental conditions. Results from the short period trials suggested a compromise between maintaining a call period and avoiding call overlap. Whether female behavior is influenced by call interference and whether males pay selective attention to distant males instead of to close neighbors must be investigated to better understand the vocal behavior of E. johnstonei.

We simulated the presence of an acoustic competitor by broadcasting conspecific playbacks to males of Johnstone's whistling frog, Eleutherodactylus johnstonei, in the field. We broadcast calls that differed in duration (short, typical, and long), dominant frequency (high, typical, and low), and period (short, typical, and long), and analyzed male vocal responses. We tested the hypothesis that males respond by escalating vocally when they are exposed to female‐attractive calls and by ignoring unattractive ones. At the population level, males responded to playbacks in ways that would potentially increase their attractiveness with regard to solo calling: males increased the duration, reduced the dominant frequency, and increased their calling effort (duty cycle), despite an increase in call period. The modification of call duration occurred only in response to playbacks of low‐frequency calls, long calls, and short‐period calls (selective response), while the modification of the dominant frequency was independent of the characteristic of the playback (fixed response). Contrary to the expected, males did not reduce the call period when they were exposed to attractive playbacks. At the ultimate level, the results suggest energy‐saving strategies. In addition, males seem to trade off call period for the avoidance of acoustic interference with attractive calls as calling effort was typically increased by increasing call duration but only rarely by reducing the call period. Interactive playbacks are necessary to better understand the calling strategies of males of E. johnstonei.