Oh Snap!

Performing a medical examination on a fish might seem like a strange idea, but it’s all part of a day’s work for snapper scientist Dr Darren Parsons.

In order to gain a better insight into snapper and its role in the ecosystem, marine ecologists like Dr. Darren Parsons are testing young snapper in different conditions to study how variations in the temperature and acidity of the oceans might affect fish populations. Effectively, this is sending the snapper to a form of boot camp and studying how they fare.  

Climate change is impacting the oceans and the marine life, potentially including species important to those living in New Zealand. With dissolved carbon dioxide levels in the ocean rising at the same rate as the atmosphere, our relationship with marine life is under threat as the oceans become more acidic; more specifically, snapper.

The collaboration is between NIWA, James Cook University and University of Auckland, with funding support from MBIE via the CARIM project, and from MPI via the Biodiversity fund. Investigations are currently focusing on snapper eggs and larvae in four different testing tanks located in Niwa’s Northland Marine Research centre in Bream Bay.

In a NZ Herald article, Dr. Parsons said,

"To be able to look at the effects of climate change on such a highly valued commercial, customary and recreational species as snapper in New Zealand is a first for us and very exciting".

CARIM’s research into these variations might also provide insight into whether or not carbon dioxide levels in the water have an effect on snapper and their ability to detect and swim away from predators. This was based on research showing that some species of fish, in high carbon dioxide conditions can be more susceptible to predation.  

Of the four research tanks, two tanks are testing temperature variations that snapper are exposed to in their early life. The other two tanks contain water that have different amounts of dissolved carbon dioxide; one of which simulates levels that are we currently have, versus the estimated levels of carbon dioxide by the end of the century.

This research will give an insight into snapper predator-prey relationships, and understanding the growth and decline snapper populations as carbon dioxide levels continue to rise into the future. Dr. Parsons said,

"This is a start at figuring out the scale of the issues and how they might unfold over time."

The scientists are also observing possible changes in sight, hearing, smell and anxiety in the fish.