Just a designation? The reality of some no-take zones in the ocean

The global implementation of no-take zones, areas in which fishing (both commercial and recreational) is banned, has been a slow process despite scientific recommendations that they are a valuable tool for conservation – and even support fisheries.  The thinking behind no-take zones is simple.  Prevent extraction from a population and that population will increase over time.  There is plenty of evidence showing that no-take zones have higher fish abundance, biomass, and species richness than comparable fished areas, and that the fish inside no-take zones are larger too.  But there is a catch… designating an area ‘no-take’ is, in itself, not enough to ensure protection.  There are all sorts of factors that can influence the ‘success’ of no-take zones, such as placing the area where it they most needed, reducing pollution from external sources, and the level of compliance and/or enforcement.  After all, if people keep fishing inside the no-take zone, it doesn’t really meet the criteria of being no-take.  Inevitably a fished zone will fail to meet expected successes of a no-take.

Located in South Sinai and within the Nabq Managed Resource Protected Area (MRPA) in the Egyptian Red Sea, the ‘South El Ghargana no-take zone’ is located between one of the most heavily fished sites in the Nabq MRPA, an a lighter-fished area.  Previous studies conducted 2, 5, and 7 years after the no-take zone was established showed that within the no-take zone, several fish families showed increases in size and abundance, and that the fished areas were delivering increased catch per unit effort for the fishers … well for a while at least.  Increases in the number of fishers and increasing non-compliance with fishery regulations from 2000 seems to have resulted in a declining catch-per-unit-effort for the fishers.  For Sahir Advani and colleagues from the University of Glasgow and the Suez Canal University, this rang alarm-bells for the state of the no-take zone, so they decided to take a look to see what was going on.

What did the researchers do? Focusing their efforts on the ‘South El Ghargana no-take zone’ and fishing areas adjacent to its borders, they used a number of different survey methods to gather the data they needed.  To assess fish abundance they team used SCUBA Underwater Visual Census, essentially trained observers swimming along transects recording families of fish.  To estimate the amount of fishing activity inside and outside the no-take zone, the observers also recorded the presence of discarded fishing gear.  For assessing the substrate itself (hard coral, soft coral, dead coral, algal turf, etc.) SCUBA divers on transects were also used, but this time the divers took a video camera with them for identification later.

What did the research tell us? In a nutshell, the no-take zone is “no longer functioning effectively”.  It is a POOP – a ‘Park Only On Paper’.  With a no-take zone, you would expect to find higher targeted fish abundance and species composition in its boundaries than in fished areas, but this was not the case.  It seems that the only statistically significant difference in abundance and species composition exists between the highly fished and lightly fished areas (the highly-fished areas having lower rates).  The team conducted a number of analysis of the data they collected, one of which looked at distance from the closest fishing village.  Piscivorous fish abundance (which are the species targeted by fishers) increased with increasing distance from a nearby fishing village.  Herbivorous fish showed the opposite trend with abundance declining the further from the village you went, possibly because there are fewer predators closer to the village. This trend was observed both inside and outside the no-take zones, and perhaps a function of fishing pressure, denoted by the amount of discarded fishing gear observed.  Yes that’s right, the team found fishing gear both inside and outside the no-take zone

How is this research useful? The research echoes recent work by another team of researchers that suggests increased fishing pressure and fisher non-compliance is on the increase inside the Nabq MRPA.  Although communities were involved in the design and placement of reserves in the Nabq MRPA (there were 5 in total), this particular zone was placed on a moderately fished area “in order to provide the most useful demonstration of a reserve effect, rather than fisher preference”.  The work highlights the importance of monitoring no-take zones long term (to detect changes), and of continuing to work with human communities to encourage compliance with the zones.  Work with – not just ‘consult’.  Especially in places where you have communities that are dependent on fishery resources, more collaborative forms of management can (but not always) prove more successful.  The researchers also suggest that no-take zones more isolated from fishing communities could be more successful.  This does raise another question; should we try look after and restore areas that already damaged (often in areas used by humans) or do we try and protect areas that are ‘healthier’ (often areas little used by people).

The paper was published in the open access journal PLOSONE.  You can have a read of it here http://dx.doi.org/10.1371/journal.pone.0126098

Image:  The two-spot red snapper (Lutjanus bohar) is one of the species recorded in this study.  This Piscivorous fish is also commercially important.  Image taken by Mohammed Al Momany, and courtesy of NOAA's Photo Library, available on Flickr