Data from: Temporal variation in the vocal behaviour of southern right whales in the Auckland Islands, New Zealand

Autonomous recorders are frequently utilised for examining vocal behaviour
of animals, and are particularly effective in remote habitats. Southern
right whales are known to have an extensive acoustic repertoire. A
recorder was moored at the isolated sub-Antarctic Auckland Islands for a
year to examine whether the acoustic behaviour of southern right whales
differed seasonally and throughout the day at their main calving ground in
New Zealand. Recordings were made in each month except June, and
vocalisations were audible in all months with recordings except January. A
total of 35,487 calls were detected, of which upcalls were the most common
(11,623). Call rate peaked in August (288±5.9 [SE] calls/hour) and July
(194±8.3). Vocal behaviour varied diurnally with highest call rates
detected at dusk and night, consistent with the concept that upcalls
function primarily as contact calls. Zero-inflated model results confirmed
that seasonal variation was the most important factor for explaining
differences in vocal behaviour. An automated detector designed to expedite
the analysis process for North Atlantic right whales correctly identified
80% of upcalls, although false detections were frequent, particularly when
call rates were low. This study is the first to attempt year-round
monitoring of southern right whale presence in New Zealand.