Objective of the flight:
Three of twelve missions were flown to assess the effectiveness of Marine Protected Areas for inshore dolphin conservation using aerial surveys to determine distribution, abundance and habitat use.
Pilot: Jay van Deventer
Aircraft: Lambada Touring Motor Glider
Beneficiary: Nelson Mandela Metropolitan University
Report from the beneficiary, Alejandra Vargas:
“This study will be conducted over a 12 month period and the first flight occurred during November 2015 followed by the second and third during January and March 2016. The Indo-Pacific bottlenose (Tursiops aduncus) and humpback dolphins (Sousa plumbea) are categorized under the IUCN Red List as Data Deficient and Vulnerable species respectively. These animals largely utilise inshore waters and are susceptible to anthropogenic pressures such as coastal development, pollution, tourism and effects of fishing. However, their movement patterns and habitat use including “hotspots” of activity (e.g. for feeding) along South Africa’s coast remain poorly understood, hampering the design of effective spatial conservation measures.
This study will contribute to a better understanding of the population abundance and spatial and temporal patterns in the distribution and habitat use of these dolphins along the southeast coast of South Africa. This would be the first known comprehensive study comparing abundance estimates using two different methodologies: boat-based surveys utilising photo identification and mark-recapture techniques to produce estimates, and aerial surveys using the distance sampling technique. The abundance estimates of the two species obtained along the coastline at different times of the year through aerial surveys will be contrasted with boat survey estimates conducted over the same period.
The aerial survey approach is considered to be most useful for longer term monitoring because it is relatively economical, effective and replicable, therefore the study also provides a comprehensive baseline for future comparison and trend evaluation. Hotspots of dolphin activity will be identified based on spatial preferences and behavioural types determined from the surveys, with relevance for spatial conservation management.”
Report from the pilot, Jay van Deventer:
“I just spent a day flying with dolphins, which was sublime. Well, technically I spent the day looking down whilst the dolphins spent the day frolicking, jumping and generally looking like they were having fun. When I wasn’t busy flying GWR, I was getting a lesson on marine mammals and sharks from a world expert on the subject.
I reason I was up there was a mission I was flying for The Bateleurs. The mission involving a research flight along the garden route counting marine mammals. The scientist involved was a Ms Alejandra Vargas, a vet, doing research at the Nelson Mandela university. Whilst an obvious authority on her chosen subject Alejandra’s good ‘air legs’ and fun attitude made her a delight on the sort of flight that usually induces motion sickness in my passengers. Indeed her obvious commitment to the quality of her data occasionally resulted in one circling for longer than one might expect, just in case the two small dolphins below us were humpbacks.
The search took around five hours most of which was spent in tight orbits at low altitude. Sweaty stuff for the pilot but the seals and dolphins were a delight. A whale carcass, however, had beached in the middle of the area where I like to kite-surf. When we flew the mission it was leaking fluids in the middle of my kite-surfing beaches and the delightful odours had attracted every shark in the area. Under the circumstances I was happy to be in the air and not in the ocean. If the number of dolpins and sharks counted is a criteria then the mission was certainly a success. I stopped counting after several hundred dolphins and Alejandra was so excited she spent the whole of the next day on a rubber duck collecting biopsy samples for study from the large pods we spotted the day before.
From a pilot’s perspective this was great fun. The conversation was educational and very interesting but the low level flying along what is doubtlessly one of the most beautiful coastlines on earth was an absolute pleasure. I would certainly have no hesitation in volunteering for the subsequent animal counts that Alejandra’s research seems to require, just for the fun of it.”