Testing marine reserve effectiveness in northern Israel:
In the Mediterranean, MPAs (including marine reserves) are becoming abundant, mostly in the western basin, and when functional, they host much more productive and diverse reefs than unprotected areas. In Israel, MPAs are few and miniscule in size, and, to date, in most of them there is no effective enforcement.
One exception is the small marine reserve at Rosh Hanikra-Achziv where partial enforcement by the Israel Nature and Parks Authority (INPA) has been conducted for more than a decade. The establishment of more and bigger marine reserves along the Israeli Mediterranean coast has been strongly advocated by the INPA and the general concept was also adapted by the Fisheries Department. As a result, initial steps to expand the Rosh Hanikra-Achziv Reserve are now underway as well as adding enforcement in other coastal reserves.
In spring 2010, and again between 2012-2015, we have been studying the benthic community around two tiny rocky islets inside the Rosh Hanikra-Achziv reserve and two similar islets outside the reserve as well as sites near Haifa. We count and size fish, count large invertebrates and estimate the percent cover of space occupiers (macroalgae and sessile invertebrates like sponges) using photoquadrats at several depths and seasons. This photographs are later analyses by a computer software.
Our findings indicate that the reef fish assemblage in northern Israel is strongly affected by depth, season and also the level of protection from fishing. The difference between fish inside and outside the reserve occurs at all depths but is most pronounced at the shallower depth strata around the wall of the islands. Most of the commercial fish are much more abundant and they are bigger, at these depths (1-12 m). These differences are a clear indication that the protection from fishing inside the reserve is effective, at least in the shallow waters very close to the islands. Invasive species represent an important component of all assemblages (fish, macroalgae and invertebrates).
A very important finding, especially when considering reef monitoring to detect and track changes in species distributions and abundances over time, is the high variability in community structure among sites and years. This variability is apparent in both fish and macroalgae assemblages, but especially in the high spatial patchiness as well as strong seasonality in the dominance of macroalgal species within and among sites. The most dominate benthic cover on the reef is low-lying turf algae, a feature common today to other Levant areas such as Turkey. This is caused mostly by overgrazing of macroalgal meadows (mostly composed of brown algae) by invasive siganids fish.