Friday, June 20, 2014

Marine Science @ Otago - Fede Baltar

Ocean Sampling Day 2014

I'm posting this on Ocean Sampling Day - 21st June 2014 - whilst the biggest global effort in marine science carried out in a single day is happening! 

Scientists from more than 150 marine research locations around the world are collecting seawater samples on the same day in order to identify all the microbes - and there are millions in just one drop!  Gene sequencing will be used to identify the DNA of the microorganisms.

The Marine Science Department at the University of Otago is one of two places in New Zealand that is carrying out scientific sampling.   Dr Fede Baltar is leading the team of volunteers carrying out the sampling.

Dr Fede Baltar is ideally suited to this role.  His research in biological oceanography integrates marine microbial ecology and biogeochemistry within the framework of physical  oceanography.  His research is based on microbes, trying to arrive at a mechanistic understanding of the regulation of marine carbon cycling to better constrain the potential consequences of climate change on the marine biogeochemical cycles and vice versa.

Dr Fede Baltar's sampling team on this historic day includes Marine Science staff and students, and students and staff from local high schools.  As Fede says:

"This is an important occasion as it is the first time scientists from all around the world are joining their efforts to do the sampling on one day and under the same conditions.  This provides us with a snapshot of the current state of the microbes that are the basis of all life in our oceans, and will help us to find out how they may respond to climate change."

All samples collected on Ocean Sampling Day will be sent to the Max Planck Institute for Marine Microbiology in Germany for analysis, and samples will be stored at the Smithsonian Institution's Natural History Museum in the USA at their brand new BioArchiving facility. This will facilitate long-term access to this material, as well as advanced analyses in the future which immensely increases the value of the project.

Monday, June 9, 2014

Marine Science @ Otago - Marta Guerra

How do dolphins react to boats and underwater noise?
 In the last two decades there has been a rapid growth in nature tourism, including boat-based whale and dolphin watching. As a consequence, coastal cetaceans have been increasingly exposed to boats and noise. Doubtful Sound (Fiordland, New Zealand) is home to a small resident population of 62 bottlenose dolphins (Tursiops truncatus), and is also a hotspot for tourism, with boat cruises running year round in the fiord. 

As part of her MSc thesis, Marta Guerra spent a year making acoustic recordings and observing the dolphins' behaviour to understand how they are affected by the presence and noise of tour boats.
 The research showed that dolphin groups with mother−calf pairs were less coordinated and more dispersed in the presence of tour boats, while groups without calves were not affected. These groups also became more vocal when boats were close and while moving away, presumably to re-establish group structure. Dolphins also responded to boat noise by altering the pitch and duration of their whistles.

These findings suggest that elevated boat noise affects communication, and that groups with calves are particularly sensitive to boat presence and noise.
 Due to the population being endangered and having a history of low calf survival, these findings have relevant implications for the management of boat tourism in Doubtful Sound.