By Sara Golaski - MSc student.
We’ve just finished up
another busy couple months of fieldwork in Lüderitz, with lots of time on the
water, and a few more interesting sightings!
During this year’s two-months in Lüderitz, we did 16
photo-id surveys (a total of 93 hours on the water) covering 868 kilometers. In
total, we took 8595 ID photos! The
information from these surveys is being used to look at abundance, population
trends and habitat use of Heaviside’s dolphins. We also did three multi-day ship
surveys, a continuation of our work looking at cetacean distribution within the
Namibian Islands Marine Protected Area. We covered a total of 2176 kilometers
in our 171 hours on these surveys and had 58 cetacean sightings from the ship.
INSHORE SURVEY EFFORTS FROM OUR RIB NANUUQ
OFFSHORE SURVEY EFFORT FROM THE RV !ANICHAB
We also had five acoustic loggers in the
water listening for dolphin clicks throughout the field season (see top map). This data will
be used to examine temporal patters in fine-scale movements of Heaviside’s
dolphins around Lüderitz. This is important to ground-truth our survey data for
defining dolphin habitat because we aren’t out late in the day or at night.
Fieldwork in Lüderitz
is always exciting, because there are so many opportunities for Heaviside’s
encounters and we really never know exactly what we’re going to find. Interesting sightings from this year include the southernmost
sighting to date of the inshore bottlenose dolphins from Walvis Bay and the
first sighting of fin whales inshore in Namibian waters! We also had 5 humpback
whale sightings, including a feeding pair and a surface-active mom/calf pair.
Humpbacks are usually seen migrating through between June and November, so
these sightings are important for highlighting “out of season” use of this
area. We even had a very rare sighting of southern right whale dolphins in the
distance from the ship!
When we aren’t at sea we keep ourselves
busy with office work too. Other accomplishments this field season include 1
paper submitted, 1 back from review and being corrected, 3 finished and with
co-authors for comment.
A great big thank you to Jean-Paul
Roux and Kolette Grobler at the Ministry of Fisheries and Marine Resources and
M&Z Motors for their support in making our field season possible.
RELEASING A STORM PETREL WHICH CRASHED INTO THE SHIP THE PREVIOUS EVENING
HEAVISIDE'S DOLPHIN CHECKING US OUT
AT SEA IN BOAT BAY ABOUT 25 KM NORTH OF LUDERITZ