A Probable Disease Epidemic in Mirror Carp Fish of Litani River
A probable epidemic has occurred in a Mirror Carp Fish of Litani River this week. Affected fish were seen lying in shallow water and gasping at the surface.
After getting notified by the LRA (Litani River Authority) about a mass mortality of fish in the Quaraoun Lake, and in accordance to our collaboration agreement with the LRA, Society for the Protection of Nature in Lebanon – SPNL aquatics expert Maher Osta headed towards the lake in the early morning of 23/4/2021.
A joint field search revealed that the dead fish (thousands of them) were all Mirror Carp (Cyprinus Carpio Carpio).
Using the “Bioindicator” approach, our expert noted the presence of at least four other species of fish in the lake, notably:
- Cyprinidae Spp. (Probably Squalius Lepidus)
- Angora Loach (Nemachelius Angorae)
- Iridescent Toothcarp (Aphanius Mento)
- Eastern Mosquitofish (Gambusia Holbrooki)
All the above fish were in very good health and even breeding, which excludes the theories of lack of oxygen (as theorized by local fishermen) and excessive chemical pollution since all the above fish species are more susceptible to those factors than the carp (Note that the lake is definitely polluted by chemicals, but not enough to cause such mass mortality of one kind of fish and exclude others).
After collecting samples of dead and dying fish, our expert performed field autopsies which revealed that all the carp fish are suffering from the following symptoms:
⁃ Internal bleeding and ruptured internal organs.
⁃ The presence of ulcers on internal and external organs.
⁃ The gills are red and relatively healthy (excluding again the lack of oxygen theory)
In conclusion of the above indicators, the most probable cause of this mass mortality in such short notice is a highly contagious viral disease outbreak targeting a specific host (Carp).
As our expert, and on the same day, found tens of dead carp with the same symptoms in the upper Litani basin (Tall el Akhdar area) which means that the whole river is probably infected, we recommend the following:
- A very strict total ban on fishing on the whole Litani River Basin and not just the Quaraoun Lake.
- Trying to contain the pandemic, since if (for example) contaminated fishing gear were used in the Assi River, and the virus spread there, the pandemic will affect not only the fisheries in Lebanon but also in Syria and Turkey.
- Immediately initiating a thorough field scan and taking samples for further laboratory analysis to try to determine the nature of the pandemic and its effects on humans and fish.
- Asking the Lebanese citizens and Syrian refugees to stop buying and eating carp, and to report anyone selling these fish to the LRA or the local authorities.