Are there fish in the margins?

A new Israeli study examined how the fish are doing in the Rosh Hankara marine reserve. Diving deeper into the issue showed that the protection of the fish decreases as they move away from its center. So how do we protect the locos that have fallen to the margins? We will protect the marine reserves

The greatest protection that the reserve manages to provide is for commercial fish, primarily the stingrays. Photo: Sarah Ohion
The greatest protection that the reserve manages to provide is for commercial fish, primarily the stingrays. Photo: Sarah Ohion

Israel's beaches are an attraction for a particularly wide audience. Almost every holiday and vacation they are visited by visitors from all over the country, so much so that sometimes they are closed due to a load of travelers. There is no doubt that our enjoyment of spending time at the beaches is also related to their level of preservation: when the beach is clean and the water is clear, it is easier to feel the connection to nature and the disconnection from the busy routine of life.

One The best ways To preserve our sea and the life that exists in it, is a creation Marine nature reserves (MPAs), which are based on the principle of limiting human activity in their territory (mainly fishing), similar to the situation that is customary in the recognized terrestrial reserves. One of the main goals of marine reserves is the restoration of species that have been damaged byoverfishing, from infections and the introduction of Invading species, in a step that provides protection for the marine ecosystem as a whole.

A new Israeli study conducted by The Israeli Association for Ecology and Environmental Sciences and the Nature and Parks Authority, and will be presented at a seminar on marine nature reserves, which will be held on October 20 as part of The Israeli Conference for Science and Nature Conservation, was carried out in the areas of the Marine Nature Reserve in Rosh Hankara. The study found that the degree of protection of the Rosh Hankara reserve for the fish that live within it, mainly the stingrays (locus), is very effective in the core of the reserve but diminishes as they move away from its center - a phenomenon called the "margin effect". This means that fish that live near the border are not protected even within the territory of the reserve itself. So how do you protect the residents of the area?

How do you check a reservation?

In Israel, there are 8 declared marine nature reserves (Rosh Hankara-Achziv, Shekmona, Dor Hobonim, Dor Islands and Meagan Michael, Yam Gador, Holot Nitsanim-Yam Ataf, Shekma and Rosh Carmel) and one approved reserve (Jaffa-Givat Aliya).

According to Sara Ohion, a marine ecologist and doctoral student in the laboratory of Prof. Yoni Belmakar at Tel Aviv University, the methods currently used to examine the functioning of marine nature reserves do not optimally represent reality. "They check the condition of the fish inside and outside the reserve, usually at only two different points." According to her, this test ignores the fact that nature is a continuous space, and that the level of protection in a nature reserve is not uniform along its entire length.

therefore, in a study she conducted and published last year in the journal Nature Ecology & Evolution, Ohion analyzed field studies from around the world that took into account the spatial features of the marine reserve, and discovered that similar to terrestrial nature reserves, also in marine nature reserves around the world fringe effect: As you move away from the core of the reserve, its protective benefits diminish, and the amount of fish that live near the border of the reserve decreases significantly. This is mainly due to intense fishing pressure outside the boundaries of the reserve, and sometimes also due to illegal fishing that takes advantage of the limited marking of the boundaries of the marine reserves.

Ohion decided to examine the situation in Israel, and went to the field. In the new study, which focused on the Rosh Hankara reserve, the spatial efficiency of the reserve was examined using a number of different sampling methods. In addition, the study examined the "spillover" distance to which the positive effect of the nature reserve spreads, and which enables the renewal and protection of species even outside the boundaries of the reserve itself.

When the reserve does keep

In the study it was found that the northern area of ​​the Rosh Hankara reserve sustains the largest amount of fish; It is true that this is not the core of the reserve, as in a normal situation of a marginal effect, but the restrictions that apply to the area due to the border with Lebanon make the northern area devoid of fishing - thus enabling the prosperity of fish within it.

As you get closer to the southern end of Rosh Hankara Reserve, the "margin effect" does exist and the amount of fish decreases significantly. Therefore, according to Ohion, the findings of the study correspond to the findings discovered in the global study, according to which the distance from the center of the reserve does result in a decrease in the protection of its inhabitants.

In addition, the research found that there are those who need the reserve in particular, and therefore enjoy its benefits in an unusual way. "The greatest protection that the reserve manages to provide is for commercial fish, chiefly the stingrays," explains Ohion. "These fish are the most profitable, and therefore also the most abundant in our region, so it is the protection and ban on fishing that make their recovery possible. In addition, these are very territorial fish, so their chance of leaving the boundaries of the reserve is small, and they are the main beneficiaries of the spatial protection."

Save Locus

Despite their importance, there are also those who oppose the establishment of marine reserves, arguing that the marine area also belongs to the public, and should be used for various purposes - including fishing. On the other hand, those who support the establishment of the reserves maintain that their existence actually benefits everyone. "The sea provides half of the oxygen we breathe, most of the drinking water (through desalination) that we consume in Israel, and serves as a source of energy, a central transportation route and an open space for the public that allows for a connection to nature and enjoyment of it," Ohion testifies. "In addition, marine reserves are islands of peace and security for marine animals. They ensure that we can continue to enjoy stable and functioning marine ecosystems for generations to come."

One of the main ways to help protect the reserve is to completely avoid using single-use plastic utensils in these areas. Photo: Shahar Chaikin
One of the main ways to help protect the reserve is to completely avoid using single-use plastic utensils in these areas. Photo: Shahar Chaikin

So how do you protect the reserve from the marginal effect? Ohion claims that methods to increase the efficiency of reserves that are offered at the global level can also help in our case. "One of the main ways to deal with the marginal effect is to create buffer zones," she explains. "These areas are a kind of intermediate areas where mechanisms are in place whose role is to maintain a balance between human activity and nature conservation. For example, limiting the amount of fishing gear or quotas of fishing spoils, which will allow nature to partially recover. Such an area will be good for everyone because it will allow increased fishing spillage from the reserve, and at the same time will cause the renewal of fishing in the reserve areas in the areas near the border."

In addition, we can also contribute our part. Due to the fact that the boundaries of marine reserves are not physical, the sea waves move the waste we throw on the beach - into the reserve itself, where the fish may consume it as food. Therefore, one of the main ways to help protect the reserve, and all the beaches and seas all over the world - is to completely avoid using single-use plastic utensils in these areas.

According to Ohion, the many efforts to preserve the marine ecosystems in Israel are indeed bearing fruit. "The update of the fishing regulations, the establishment of the marine enforcement unit and the expansion of the marine reserves in Israel are a positive and welcome trend whose results can be seen on the ground; our Mediterranean Sea is more alive than it was here a decade ago," she testifies. "But at the same time, the threats to the sea are also increasing: gas drilling, seawater warming, desalination plants, many infections and increasing human pressure. That is why we must continue to act vigorously, and reach a situation where at least 30 percent of the marine area will be protected in marine reserves by 2030." .

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