Fish Kill

By Abdel Aziz Kordieh & Mohammad Asaad 

Picture taken from WIRED.com

Imagine you were walking one day on the shore and all of a sudden you saw a huge amount of dead small fish on the sand. You get shocked and start proposing reasons for such accident, “for sure the fish didn’t get thrilled and decided to discover the unknown lands. And why isn’t it only small fish on the shores, where are the big ones!?”. Well, this same incident happened on 30 September 2020 at the Saint Simon Beach, but I wasn’t walking on the shores, I knew from the news that spread on that day. I decided to investigate the reasons, so let me involve you more in my search.

The fish could have died from reduced oxygen in water. Where oxygen enters water through diffusion, the amount of oxygen that can be dissolved in water depends on the atmospheric pressure, the water temperature and whether the water is salty or no.  For example, at 20 °C (68 °F) and one atmosphere of pressure, a maximum of 8 mg/l of oxygen can dissolve in sea water (35 mg/l salinity. The amount of oxygen that can be dissolved in the water decreases by about 1 mg/l for each 10 °C increase in water temperature above 20 °C.

Moreover, dissolved oxygen in water (DO) is nowadays a big part of fish kill not only in Lebanon, but all around the world. Most DO-related fish kills occur in the warmer months from May through September, although winter cold fronts can also trigger DO lags. A typical scenario occurs when fish are observed at the water surface appearing to gasp for breath.   

However, I realized that this couldn’t be the reason because we saw only small fish on the shores and we didn’t see any small fish on the water’s surface striving for a breath. Then what could be the reason? We have to put an end to such misery.

I decided to call my friend, he is a fisherman and for sure knows the sea more than I do. I was astonished by what he told me, however, I realized I founded the answer of my question. I asked him if fishing nets could be the reason behind such kills, he replied that “indeed it is.” He started explaining about a fishing method using a huge net called Jaroofe (جاروفة بر). Let us see what he said. “TheJaroofe is a very large net, it consists of: cork at the upper end, the net in the middle and lead at the lower end (for it to go deep in water). It has one tall rope extended from each side and reaching the land, the fisherman will hold these ropes tight, after they spread the net in water, then start pulling them off. It’s called Jaroofe because the net consists of two layers: the inner layer consists on normally spaced net; however, the outer layer consists of very finely spaced net that takes everything on its way. This ensures that nothing escapes from the net (except water!)” he elaborated.  After the net is pulled off water, the fishermen take the fish off. However, every type of fish needs to be at a certain size (greater than 20 cm) for the fisherman to be able to sell. So, after taking the desired sizes, small fish remains. The fish are still alive at this stage and the fishermen can return it to water; Sadly, most of them don’t. They keep them on the shores to die in peace. At this stage, I asked my friend in surprise “but isn’t the fishermen hurting themselves by this act? They’re distorting the balance and can reach a stage where fish will be so scarce”. He replied “what you’re saying is true, the amount of fish that are left on the shores weighs about 40 Kgs. This amount will weigh about 400 Kgs if left in the sea for a month!!”.

Though I was happy to discover the cause behind the accident, I was disappointed to see such illegal practices. My friend told me that this method of fishing is forbidden by the government, however fishermen could still find a way to do it. I believe that further strict sanctions should be imposed and applied on such practices. Unfortunately, such practices could be done with the protection of the government itself by bribing the officers with certain shares of the profits.

My investigation ends here, but I don’t know whether this illegal practices will come to an end.

Second Authors:

  • Alaa Al Mikkawi
  • Abir Hajj Houssein
  • Amira Fawaz
  • Carl Zoghzoghi
  • Christelle Rassi
  • Jawad Hmayed
  • Malak El Kassamani
  • Marc Darazi
  • Mohammad Daoud 
  • Nadeen Abbas

Leave a Reply

Your email address will not be published. Required fields are marked *