Abstract:
This paper presents data from 48 resightings of 16 southern right whales that
were satellite-tagged on the South African coast in September 2001, up to and
including 2012. Tag performance in terms of number of days with locations received
was significantly higher in males than females, and lowest in cows with calves, and
attributed to behavioral differences leading to variable degrees of antenna damage.
Resightings occurred from 4 to 4,054 d after tagging: tags were retained in all
whales seen within 27 mo, but were apparently shed in all but one individual seen
within 36 mo of tagging. The exception was a whale that still had the tag present
11 yr after tagging. Healing at the tag site occurred gradually and within 5 yr of
tagging (and 2 yr after tag shedding). No significant difference in the subsequent
frequency of calving was detected between 12 tagged and 382 untagged females
photographed contemporaneously, and although statistical power was low, a 21% or
greater reduction in calving rate in tagged females would seem incompatible with
the observations. The death of one female 3 yr after tagging was more likely attributable
to a ship strike on an animal debilitated by a prolapsed uterus.
