Novel acoustic intruders disrupt frequency partitioning and vocal competition

Evidence

Climatic variability may produce an increase of vocal repertoire in vertebrates, as is the case with mockingbirds, a group of species distributed in a variety of habitats of the New World (Botero et al., 2009). Species living in more variable and unpredictable environments (as expected under a climate change scenario) should be able to learn and invent new syllables, as argued Botero et al. (2009), or modify their repertoire (Laiolo, 2008; Laiolo and Tella, 2006), remodulating their acoustic niche with important consequences to interspecific competition. Particularly, when sound-generating organisms add signals into an assemblage for the first time, frequency partitioning can rarely be achieved, and this can create masking effects and confused messages. For instance, when the playback song of the Red-billed leiothrix (Leiothrix lutea) was applied inside an area at high density of blackcaps (Sylvia atricapilla), which had probably not previously heard such exotic species, the latter species suspended their song, singing again only during the Red-billed leiothrix’ singing pauses (Farina, submitted for publication). In this way, the playback of this new species acts as an intruder preventing blackcaps from maintaining an intense net of vocal interactions necessary for mating and territory defense. — Bernie Krause and Almo Farina, Using Ecoacoustic Methods to Survey the…, 45

Categorization

• ADDENDUM: Reinforces the biophony/anthropophony partition central to the Soundscape Ethnography course, showing how introduced acoustic signals destabilize established niche partitioning — the same intrusion logic as anthropophony over biophony in Krause’s niche hypothesis.
• XREF: connects to: Species in a habitat partition acoustic space into distinct non-overlapping bandwidths. — Bernie Krause and Almo Farina, Using Ecoacoustic Methods to Survey the…, 39; Chickadees pitch-shift incoming biophonic signals to create their own private bandwidth. — Bernie Krause and Almo Farina, Using Ecoacoustic Methods to Survey the…, 44; Each species occupies a distinct acoustic niche to avoid signal competition — Almo Farina, Soundscape Ecology: Principles,…, 387 (+4 more)

Related

• Species in a habitat partition acoustic space into distinct non-overlapping bandwidths. (similarity 0.85)
• Chickadees pitch-shift incoming biophonic signals to create their own private bandwidth. (similarity 0.84)
• Species time-share the acoustic space to minimize signal interference (similarity 0.83)
• Each species occupies a distinct acoustic niche to avoid signal competition (similarity 0.82)
• Four hypotheses organize the study of animal acoustic signaling (similarity 0.82)
• Species shift calls to ultrasonic frequencies to escape constant noise masking (similarity 0.80)
• Acoustic niche partitioning operates through both spatial movement and temporal scheduling (similarity 0.79)
• Habitat structure drives the evolution of animal vocal signals (similarity 0.79)
• Habitat-specific ambient noise can drive the evolution of animal signals (similarity 0.79)

Broader Connections

• Each species occupies a distinct acoustic niche to avoid signal competition #corroborates (0.85) — Almo Farina, Soundscape Ecology, 387
• Species shift calls to ultrasonic frequencies to escape constant noise masking #exemplifies (0.75) — Almo Farina, Soundscape Ecology, 1288
• Acoustic niche partitioning operates through both spatial movement and temporal scheduling #expands (0.72) — Almo Farina, Soundscape Ecology, 474
• Body size constrains the frequencies animals can vocalize #qualifies (0.70) — Almo Farina, Soundscape Ecology, 385