Marine Conservation Photographer, Jean Tresfon embarked on the first official aerial southern right whale survey of the 2021 season for the Mammal Research Institute Whale Unit (MRIWU) on Tuesday, 3 August.
Piloting a gyrocopter with MRIWU researcher Dr Els Vermeulen on board, Tresfon surveyed the Cape Coast from Walker Bay to Struisbaai. Their survey was interrupted intermittently by fog, but clear weather in key locations such as the coast of De Hoop Nature Reserve resulted in reliable counts.
“Our first hotspot area was Walker Bay which yielded 3 cow/calf pairs and 29 unaccompanied adults for a total of 35 southern right whales, most of which were in the sanctuary area close to the Klein River mouth. It is probable that some of the unaccompanied adults are pregnant females which have yet to give birth,” reported Trefson in a Facebook post.
“Light aircraft reported gaps in the fog near our main target area at Koppie Alleen in the De Hoop Nature Reserve, so we decided to carry on with the survey. The fog finally moved a little way offshore at Arniston and by some small miracle the main whale nursery ground was in the clear! We counted 132 cow/calf pairs and 16 unaccompanied adults at De Hoop for a total of 280 southern right whales.”
Their count for the day was 158 cow/calf pairs and 52 unaccompanied adults for a total of 368 southern right whales. “This number is higher than the August counts for 2019 and 2020, it is still much lower than hoped for and indicative of the feeding challenges these animals are facing in the southern oceans. Hopefully we will do another count in early September around the peak of the season and possibly record a higher number.”
Vermeulen said that, as expected, the vast majority of southern right whales were located near Koppie Alleen in De Hoop Nature Reserve. “A total of 141 females with an associated calf located right in front of the De Hoop Collection, or nearly 90% of all females with calves were counted in their main breeding area (defined as Walker Bay to Saint Sebastian Bay). Vermeulen says these numbers are an indication that this year will result in a low-count year much like 2017 and 2019. In normal conditions more than double this amount would be expected.
William Stephens of De Hoop Collection who funded the flight explained that De Hoop offers a nutrient bay near Koppie Alleen that is shallow and sheltered which is an ideal preferred breeding site with no boat disturbances. “Much depends on the feeding conditions in the Southern Oceans where they feed before coming in to our waters – Ocean warming has affected these feeding grounds,” says Stephens. “In normal conditions we would expect more than double this amount. It also points towards the likelihood that next year will be a bumper year much like 2018 when about 1200 Southern Right Whales were counted off De Hoop alone.”
Whale tourism is an important draw card for visitors to De Hoop which boasts the best land based whale watching on the South African coast. De Hoop Collection has a variety of accommodation options from self catering bungalows to large cottages and are currently offering reduced rates until the end of August.
ALSO READ
