MISSION 03 of 2012
Name of Mission: Namibian Coastal Survey 2012
Date of Mission: 3 and 4 March 2012
Aircraft used: Cessna 182
Pilot: Nico Louw
Beneficiary: Namibian Dolphin Project
Intro for the Annual Report:
This two-day mission was requested by Ruth Leeney of the Namibian Dolphin Project. Ruth needed another of her annual surveys to count dolphins, whales and turtles along the Namibian coast.
The flights took place on the 3rd and 4th of March 2012, in a Cessna 182 flown by Nico Louw, one of our three pilot members based in Namibia.
The reports presented below were prepared by Nico Louw and Ruth Leeney.
Objective of the Flight
To cover the entire Namibian coastline and record all whales, dolphins and other marine species of interest, in coastal waters.
Pilot’s report by Nico Louw
This was a mission that required quite a bit of preparation, as the flight to the Cunene covers an inhospitable area where very few flights take place. The two flights were from Walvis Bay to the Cunene Mouth (1500km), and Walvis Bay to the Orange River Mouth (also about 1500km). However, with the New 406 Mz ELT, a satellite/GPS alerting system, which is compulsory in Namibia, it was not as daunting as it could have been.
The pilot’s briefing had to include aspects that are unique to the skeleton coast. Cold, wind, sand, high radiation, etc, all of which means that mistakes are out of the question!The flight was done at 600-700 feet and about a kilometre off-shore. Flying along the coast at that level, with winds of up to 35 knots, consumes a lot of fuel. Consequently, we had to refuel no less than five times in the 19,75 hours of flying that this mission required: twice in Luderitz (I never knew sand could get that deep inside one’s ears!) and twice in Palmwag, and the cost of fuel was a cool N$23 per litre.
All went well with the actual count, and the observers all slept throughout the return flights – due to exhaustion.
As always, it was a privilege to fly for Bateleurs.
Was the objective met?
My first objective on both days was to conclude the flight safely. My second objective was to ensure that none of the passengers suffered airsickness. The first objective was met, but unfortunately I was not successful with the second objective – with winds of 35 knots a short overland flight demonstrates how quickly one becomes nauseous.
Beneficiary’s report by Ruth Leeney of the Namibian Dolphin Project
The aim of this mission was to fly the entire Namibian coastline over two days, in order to provide a snapshot of the whales, dolphins and other large marine species using Namibia’s coastal waters. The Namibian Dolphin Project (NDP) has been carrying out research in Namibian waters since 2008, but we have used mainly boat-based survey methods and have thus been restricted to the safe and sheltered areas of Walvis Bay and Lüderitz Bay. Whilst these areas are likely important refuges for marine species such as dolphins, it is also important to understand the distribution and number of marine animals along the rest of the coast and in offshore waters. A more complete picture of Namibia’s coastal marine life allows managers and conservators to better predict the effects of human activities on our unique and vulnerable marine life.The results of these aerial surveys, along with ongoing research by the NDP in the Namibian Islands Marine Protected Areas, thus forms the first step towards a more comprehensive picture of the key marine species present and important areas for them in Namibian waters.
For the two-day aerial survey, we flew along a line parallel to the coast, approximately 150-200 m from the surf zone. The crew consisted of our pilot Nico Louw, two observers, left and right, and a photographer. On the first day, the sea conditions were reasonably calm and the mist had cleared as we flew towards the town of Walvis Bay and turned northwards. We covered the entire coastline from Walvis Bay to the Kunene River mouth, stopping at Palmweg to refuel. By the end of the day we had recorded 64 sightings of Heaviside’s dolphins, one ocean sunfish and one bottlenose dolphin.
The following day, we set out to cover the southern part of the coast. As we flew over the salt pans and the Walvis Bay lagoon, flamingos flying far below us, the sea ahead was calm and turquoise. This section of the coast was covered in a previous survey, also supported by the Bataleurs, flown in November 2010, where we gained the first insight into the large numbers of Heaviside’s dolphins found south of Walvis Bay. We again sighted an abundance of these small dolphins, found only in the Benguela ecosystem, during our recent survey, with an apparent hotspot just south of Sandwich Harbour. The waters south of Lüderitz proved surprising, not for any of the focal species such as dolphins but for another ocean giant – Mola mola, the ocean sunfish. This is the heaviest bony fish in the sea (sharks can weigh more, but they are cartilaginous fish), and the heaviest individual on record weighing 2235 kg! They are odd-looking fish, with a somewhat circular, flattened body and two long, pointed fins – they look as if their tail has been cut off. Their Latin name ‘mola’ means millstone, and refers to their round shape. In total we sighted 25 sunfish, and no doubt there were many more, further offshore. Along the southern section of coast we had 69 sighting events; over and above the sunfish we saw 88 Heaviside’s dolphins and one bottlenose dolphin.The data collected provide a unique and novel picture of near-shore marine vertebrate distribution, and especially provide insight into the way in which Heaviside’s dolphins use almost the entire Namibian coastline. Heaviside’s dolphins are endemic to the Benguela Current ecosystem and through research, we can better understand the conservation status of this unique species.
More information on the Namibian Dolphin Project can be found at HYPERLINK “http://www.namibiandolphinproject.com” www.namibiandolphinproject.com
Was the objective met?
The objectives of this project were met – the entire coastline was covered over a two-day period, Although no whales or turtles were sighted, a significant number of Heaviside’s dolphins were seen, as well as a previously undocumented hotspot for sunfish in southern Namibian waters. The data collected will be added to the Namibian Dolphin Project’s database and will be provided to local conservation authorities, ensuring that our understanding of marine megavertebrates in this region continues to grow.