Patterns of daily and seasonal calling activity of a direct-developing frog of the subtropical Andean forests of Argentina

Abstract

Climate often regulates different aspects of the life cycle and activity of amphibians. Climatic seasonality may impose severe restrictions on breeding patterns of directdeveloping terraranan frogs. We studied the influence of abiotic cues on calling activity of males of the direct-developing frog Oreobates discoidalis in the Yungas forests of north-western Argentina. Vocalization activity and daily emission pattern of the vocal repertoire were registered with a frog-logger, and climatic variables were registered with a data logger. We sampled two reproductive seasons from 2010 to 2011. We used ordinal logistic regression to evaluate the relationship between independent climatic variables and the intensity of calling activity. The calling season of males of O. discoidalis was triggered by the first rainfall of the aestival season. The species could be defined as crepuscular -nocturnal with a calling activity peak at dusk. Sporadic calling activity during day time was associated with conditions of high humidity and rainfall. Both the emission and the intensity of the advertisement call activity were influenced by time of the day, high levels of relative air humidity and presence of rainfall; air temperature was not a determinant factor in the calling activity of this frog species. Territorial calls were strongly associated with full chorus activity that could be associated with a mechanism of inter-male spacing.

The use of bioacoustics in anuran taxonomy: theory, terminology, methods and recommendations for best practice

“…Relatively few studies target anuran assemblages (Bridges & Dorcas 2000;Todd et al 2003;Acevedo et al 2009;Acevedo & Villanueva-Rivera 2006;VillanuevaRivera 2007;Waddle et al 2009;Llusia et al 2011;2013a, b;Ospina et al 2013) or concern the acoustic monitoring of single rare frog species. Results are potentially relevant for taxonomy, if comprehensive and quantitative call descriptions are provided (Akmentins et al 2014;Jansen et al 2016b;Willacy et al 2015). However, recordings obtained from automated devices can be affected by environmental effects (e.g., differential excess attenuation, reverberation on trees and shrubs) and might be biased if calling individuals are too close or too far from the automated recorder, so their use in taxonomy must be approached with caution.…”

“…Many studies use Frogloggers (construction manual given by Peterson & Dorcas 1994;e.g., Acevedo & Villanueva-Rivera 2006;Akmentins et al 2014) or the Songmeter recorders (Wildlife Acoustics Inc.; e.g., Lehmann et al 2014;Zwart et al 2014;Ganchev et al 2015;Jansen et al 2016b). For the automatic detection of particular animal sounds there is a variety of algorithms that can be used, and several programs on the market have already implemented species identification tools for several taxonomic groups (Ganchev et al 2015).…”

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“…Relatively few studies target anuran assemblages (Bridges & Dorcas 2000;Todd et al 2003;Acevedo et al 2009;Acevedo & Villanueva-Rivera 2006;Villanueva-Rivera 2007;Waddle et al 2009;Llusia et al 2011;2013a, b;Ospina et al 2013) or concern the acoustic monitoring of single rare frog species. Results are potentially relevant for taxonomy, if comprehensive and quantitative call descriptions are provided (Akmentins et al 2014;Jansen et al 2016b;Willacy et al 2015). However, recordings obtained from automated devices can be affected by environmental effects (e.g., differential excess attenuation, reverberation on trees and shrubs) and might be biased if calling individuals are too close or too far from the automated recorder, so their use in taxonomy must be approached with caution.…”

“…For the long-term acoustic monitoring of natural habitats, autonomous, waterproof recording devices (Automatic Recording Systems, ARS) can be installed in the field. Many studies use Frogloggers (construction manual given by Peterson & Dorcas 1994;e.g., Acevedo & Villanueva-Rivera 2006;Akmentins et al 2014) or the Songmeter recorders (Wildlife Acoustics Inc.; e.g., Lehmann et al 2014;Zwart et al 2014;Ganchev et al 2015;Jansen et al 2016b). For the automatic detection of particular animal sounds there is a variety of algorithms that can be used, and several programs on the market have already implemented species identification tools for several taxonomic groups (Ganchev et al 2015).…”

Seasonal Reproductive Dynamics of a Lek-Breeding Neotropical Treefrog is not Organized by Male Size (Anura, Hylidae)

“…Among anurans, social organization is directly related to body size and reproductive traits such as chorus structure, male territoriality, pair formation, breeding site choice, and temporal breeding pattern (Wells, 1977;Martin et al, 2011;Rosa and Andreone, 2012;Sousa and Ávila, 2015;Berec, 2017). Moreover, temporal and spatial breeding patterns are affected by abiotic (e.g., climate and availability of reproductive resources) and biotic (e.g., habitat use, abundance of individuals, reproductive strategies, and adult life span) factors (Crump, 1974;Gally and Zina, 2013;Akmentins et al, 2015;Hurme, 2015;Luna-Gómez et al, 2017;Leivas et al, 2018). The majority of the anuran species from tropical areas with well-defined seasons possess seasonal reproductive dynamics associated with the hotter and rainier periods of the year (Shahriza et al, 2010;Van Sluys and Guido-Castro, 2011;Waldez et al, 2011;Schalk and Saenz, 2016).…”