THE SOUNDSCAPE OF MAR CHIQUITA COASTAL LAGOON (ARGENTINA)

CERAULO M.; SAL MOYANO M. P.; BAZTERRICA MC; HIDALGO F.; PAPALE E.; GRAMMAUTA R.; GAVIO M. A.; MAZZOLA S.; BUSCAINO G.

Mar del Plata

Congreso; Congreso Latinoamericano de Ciencias del Mar COLACMAR; 2019

The study was conducted in the framework of the Italian-Argentinian scientific cooperation (project CAIMAR JL funded by CNR and BOSS funded by Italian Ministry of Foreign Affair - MAECI) and aimed to study the temporal and spatial patterns of the soundscape in the Mar Chiquita coastal lagoon (Buenos Aires, Argentina). It is an important biodiversity area used for tourism and recreation activities, categorized as Man and the Biosphere Reserve (MAB, UNESCO, Iribarne 2001). The study was conducted during autumn-winter (May and June) and spring (November) seasons. Acoustic data were collected using 4 autonomous recorders located a different distance from the mouth to the headlands of the lagoon. A 5th hydrophone was located close to the aggregates ("reefs") of an invading polychaete in order to investigate the effect of these on soundscape. The reef-like constructions are an important source of habitat. A high abundance of the crab Cyrtograpsus angulatus inhabiting reefs was recorded (Schwindt et al. 2001; Méndez Casariego et al. 2004). Through visual and automatic analysis of data collected, we showed that the biophonic component of the soundscape is dominated by fishes (mostly Pogonias cromis chorus) and crustaceans sounds that presented a seasonal presence (increasing during reproduction activity) and different spatial patterns, with higher activity during spring in the locations closer to the mouth of the coastal lagoon. These areas are also the most affected by human generated noise. The analysis of acoustic energy revealed that the strongest driver for soundscape in the area is due to low-frequency (< 100 Hz) noise that showed a strong periodicity probably connected to tide dynamics. The polychaete reefs determined changes on lagoon soundscape as for biophonical presence and its geophonical effects, making it discriminable from the closest site far from reefs. The presence of reefs makes the soundscape locally distinguishable and this information could be used by crustaceans and fish as cue for orientation along the lagoon.