Habitat connectivity improves fish numbers

Marine reserves located in areas where mangroves and reefs are close together help to successfully increase fish numbers.

This is according to an extensive study by scientists at the Australian Rivers Institute which has shown that connectivity between coral reefs and mangroves can improve the performance of marine reserves(green zones) in the Moreton Bay Marine Park, Queensland.

Funded by a $750,000 ARC linkage grant, the research is part of a major collaboration with the Queensland Department of Environment

and Resource Management and CSIRO and is reported in prestigious science journal Conservation Letters http://doi.wiley.com/10.1111/j.1755-263X.2011.00204.x

“In Moreton Bay, this translates to more harvested fish, especially

yellowfin bream, moses perch and black rabbitfish in marine reserves

where both habitats occur in close proximity,” said PhD student and lead researcher Andrew Olds.

“The results are good news for fishermen — these fish move about the seascape and can be caught when they move out of the green zone

to feed or spawn.

“We now have strong evidence that these green zones are supporting more fish, however their ability to do so can be significantly enhanced

if we can make sure they are located in the right areas.”

In addition, the research has also suggested that protected reefs near to mangroves may be better placed to recover from major disturbances such as the flooding of the Brisbane River that was seen over the 2010-2011 summer.

Chief investigators on the ARC Linkage Grant, Professor Rod Connolly and Dr Kylie Pitt said that green zones with well-connected

reefs and mangroves also support more herbivorous fish.

“These fish graze on algae, which compete with coral for living space and their efforts can tip competition in favour of coral and help

maintain reefs in a healthy condition,” said Professor Connolly.