Are Icelandic harbor seals acoustically cryptic to avoid predation?

Male harbor seals (Phoca vitulina) produce stereotypic underwater roars during the mating season. It remains unclear to what extent roar structures vary due to predation levels. Here, seal roars from waters with many (Iceland) and few (Denmark and Sweden) predators were compared.

Temporal and spatial variation in harbor seal (Phoca vitulina L.) roar calls from southern Scandinavia.

Male harbor seals gather around breeding sites for competitive mating displays. Here, they produce underwater vocalizations possibly to attract females and/or scare off other males. These calls offer prospects for passive acoustic monitoring.