New Award aimed to tackle Ghost Gear made in memory of Ocean Defender
An article about the effects of Ghost Gear on marine life, and solutions being developed to try and tackle the problem. Written by Elle Cote.
August 20th 2019
Plettenberg Bay, South Africa, is home to some of the world’s most iconic marine species including humpback whales, killer whales, great white sharks and bottlenose and common dolphins. This biologically diverse bay is home to our Ocean Research and Marine Conservation Volunteer and Intern Programme. Run by ORCA, otherwise known as the Ocean Research Conservation Africa Marine Foundation, this project allows marine conservation volunteers and research interns to work on dolphin and whale research projects, in addition to working alongside the community in education programmes.
On the 29th June intern Flavio joined our Ocean Research and Marine Conservation Programme and began collecting data in order to determine the reliability of whale watching as a source of scientific research. Over the next three months Flavio joined the daily whale watching trips.
“Tracking of whales from boats was done from the crow’s nest atop a 14m boat at about 3m above sea level. Observations started as soon as a whale was spotted and the species identified. Records of the time, weather conditions and location were kept for each observation. ID photos were taken where possible to help other research in the area.”
These observations were coupled with those from land carried out a few times each week. Behavioural data was collected from observations along with the presence of juveniles. Reactions to whale watching boats were recorded. Flavio then carried out data analysis.
“Over a total of 52 boat encounters by cetaceans recorded, 16 resulted in avoidance behaviour from the animals, 10 displayed friendly approach behaviour and 26 showed neutral reactions to the boat. Proportion of observed friendly behaviour is seen to increase when calves are present and avoidance decreases whilst proportion of neutral reaction remaining constant. Thus, overall animals were significantly more likely to remain neutral to the presence of the boat although avoidance was more predominant than friendliness, to the exception of cases where calves were present.”
Differences in observed behavioural states were also analysed with travelling found to have been observed significantly more than all other behaviours. Flavio goes on to detail that these figures are linked to minimal observations of other behavioural states compared with a large amount of time observing animals on the move. Finally the differences in those observations taken from land and at sea were analysed with results indicating no real variation in behaviour.
Flavio ends with a discussion on the benefits of whale watching highlighting its role in providing easily accessible and cheap data for scientists. He also points out the surprising similarities between observations from land and those at sea, suggesting an equal reliability. Later discussions also touch on the impact of whale watching on natural cetacean behaviour.
“My results show very little avoidance of whale watching boats. Neutral reactions tend to predominate, whilst friendly reactions are rarer.”
“The general linearised models failed to show any difference in observed behaviour due to the platform used to record the data. This suggests that whale watching was not having an effect on the behavioural budget if the observed species. However, the current study encompasses too many different species with different biologies and life histories to accurately describe whether behaviours were affected by the presence of the boat.”
Flavio finishes by suggesting further studies in Plettenberg Bay are necessary in order to guide future efficient management strategies and preserve the environmental integrity of the Bay.
“I suggest that more effort be put in studying the effects of whale watching and the species of Plettenberg Bay as whale watching in the area only consists of two boats and efficient management could maintain the area for insightful future research.”