Memories from Manot HaKer - fish stories

About Lev Filchzon's shelved research and the experiment that showed that it is worthwhile to grow fish in the Naot HaKer, which was shelved and found only for the jubilee celebrations of the first nuclear explosion on the ground

The first part of the article

After the settlement and the development of agricultural fields, and when the settlers despaired of the herd of cattle, they asked Fr. Mendelson (who was a friend) if he thought it was possible to raise fish there?

In his pleasant "Yikit" way that instills confidence, Mendelssohn answered of course, saying that she stimulated the project, two pools were dug that were fed with warm and salty water. The tilapia fry grew and the success was clear, in order to continue, funding was needed, the "agency" refused to help without supporting research, the settlers turned to Prof. Lev Fishelzon and he sent a young student to conduct the research.

Positive and surprising results that were supposed to reach the "settling bodies"... were put away and disappeared (toward the meeting of the settlers the research was found). The entrepreneurs - the settlers did not wait for the publication of the results, the real nature of which was known,

In 1967 there was a recession and tools for work (tractors) could be obtained cheaply, operator D.9 started work, the operator was called to the reserves (Six Day War) and when he returned he announced that he had been drafted for a long time and thus the fish enterprise faded away.

Summary of results and conclusions from a study by Yossi Loya (today Prof. Loya) into the feasibility and viability of fish farming in the Banaut HaKachar ponds, the research was conducted in the mid-sixties and funded by the residents of Naot HaKachar. The results and conclusions of the research that were ready for publication as early as 1967... disappeared/ were deleted

Two ponds dug by the settlers, ponds - A - measuring 8 dunams, pool - about 7 dunams. The pools are fed with brackish water at a level of about 2000 mg. The water temperature is between 26 and 29 degrees. The ponds were populated with hybrids of two species of tilapia, the Nile tilapia and the golden tilapia Tilapia nilotika & T aurea. The population (and collection) was in three cycles. To serve as a yardstick for the development of the tilapia, carp (Cyprinus carpio) were introduced into the ponds

During the study, nutrients were added: poultry manure + sorghum, only to one pond (b) the amount of food according to the norm in Israel in the north. The pools were populated on April 23 (66), emptied and populated a second time on August 27 (66), emptied and populated a third time on January 8 (67). (The research does not indicate that the third emptying/collection was in April (67). The research showed that: the water temperature ranged between 26 and 29 degrees, the salinity of the water in the pools increased (between emptying and emptying) - clear.

The oxygen level increased in cool water and decreased in warm water - obviously. Up to eighty days after the population, the weight of the fish in both ponds increased to a similar extent.

Later, the fish of pond B raised a little more (0.5%). Weight of pond fish - A. The differences are not significant! The fish weighed between 400 and 500 grams. (The researcher does not indicate that there is abundant natural food in the ponds: mosquito larvae and other insects, plant pollen and seeds, plankton and phytoplankton).

The increase in the length of the fish was also measured and here too there were no significant differences between the ponds. (Amiram - the institution, says that "there were fish the size of a frying pan"). According to the tables, it turns out that about 55 kg of fish were produced from each dunam, when you multiply this by three cycles, you get 165 kg of fish per dunam per year. According to the researcher, it is possible to reach 250 - 300 kg per dunam per year, (without feeding, without expenses for pumping water, without harming environmental sources and resources).

Here comes an explanation (the caption is not clear) how to prevent population explosion in ponds, the accepted method is to populate male fry and female fry in separate ponds.

In conclusion, the study states that it is possible to reach three breeding cycles each year because of the stable water temperature, a place / pond can be allocated where there will be males and females that will spawn fry three months before the spawning date in the north of the country, that is, to produce breeding material for fish breeders in the north.

According to the research data, growing tilapias in Naot HaKer will be at least three times more profitable than growing them anywhere else in Israel

Addendum from personal information, porcupines (Mugil cephalus) were brought to the ponds, and after a short time it became clear that the unique conditions allow spawning. Laying boars occurs only in nature and to date they have not been able to create conditions that would "convince" boars to reproduce under artificial conditions. After the official treatment of the ponds stopped, the fish continued to grow in addition to tilapias and carp, carp grew here to huge dimensions, finally due to lack of care in the kind that supplied water to the ponds, the ponds dried up completely.

One last thing: the new settlers of Ein-Tamar built fish ponds on the spot. Probably because of poor management the business did not succeed. In a conversation with some of the settlers, it turns out that the initial venture was only known to them as... "an experiment with no result", or as a "curiosity", the results of the research... "What research?" It is possible that if Ein-Tamar had the data collected in the past, the fishing enterprise would have risen and flourished.