Results of the eighteenth winter waterbird census in Libya in 2022.

Background: Libyan wetlands are diverse; the coastline of Libya, in particular, has different kinds of wetlands, such as salt marshes, bays, lakes, lagoons, and islands. These varieties in habitats provide good shelters and foraging sites for migratory birds during their journeys between Eurasia and Africa. Since the beginning of the Libyan winter census of waterbirds International waterbirds census (Libya IWC) in 2005, which continued regularly until 2012, it has had relatively the same performance in the number of covered sites. However, since 2013, due to the security situation that Libya has experienced due to wars and conflict, which negatively affected the quality of the IWC in Libya, the number of sites has dramatically decreased, reaching only six locations during the middle of the previous decade. Aim: The IWC 2022 aimed to count the birds along the Libyan coast from January 10 to 29. Methods: The census activities were conducted from dawn to dusk during the study period by using high-quality Telescopes, binoculars, and digital cameras for the documentation. Point transects method was used to cover the sites. Results: The results of this year showed that a total of 64 sites were covered, and 68 species of waterbirds were counted, with an abundance of 61,850 individuals. During the census period, a total of 52 non-waterbird species found in Wetlands were recorded, and the number of individuals was 14,836 birds. A total of 18 threatened species were observed during this survey, 12 of them are mentioned in the International Union for Conservation of Nature Red List, and nine species are mentioned in the regional activities center of specially protected areas annex II as threatened in the Mediterranean, where the species; Larus audouinii (Payraudeau, 1826), Larus genei (Breme, 1839), and Puffinus yelkouan (Acerbi, 1827) are mentioned in both of them. Conclusion: The lack of the number of ornithologists and bird watchers is still one of the factors affecting the quality of the IWC in Libya, as well as lack of funding remains an important factor that plays a major role in the success of the waterbirds census.

Pathological lesions associated with Vibrio infection in Atlantic horse mackerel (Trachurus trachurus L., 1758) from the western coast of Tripoli, Libya.

Background: Vibrios are aquatic bacteria causing Vibriosis in humans and aquatic animals. Vibriosis is a significant disease of cultured and wild fish. Aim: The present study aimed to address the impact of Vibrios on the health status of Trachurus trachurus inhabiting the coastal area of Tripoli. Methods: A total of 100 samples of (T. trachurus) were collected randomly from the Western Coast of Tripoli and Bab Al-Baher market, throughout the period from spring 2019 to summer 2019. All the sampled fish were examined externally and internally and lesions were recorded. Bacterial isolation from the liver and kidney was carried out using the appropriate culture media. Tissue samples were taken from the liver, kidney, and spleen in 10% neutral buffered formalin for a histopathology examination. The tissue sections were stained with hematoxylin and eosin to assess morphologically and Perl's Prussian blue for the demonstration of ferric iron. Results: On average 69% of the infected fish exhibited at least one pathological lesion. Vibrios were recovered from 90% of the examined fish. The histopathological changes of the liver showed severe congestion of blood vessels (BVs), mononuclear cell infiltration surrounding a bile duct, granular degeneration and coagulative necrosis of hepatocytes in the centrilobular area, marked vacuolar degeneration of hepatocytes, activation of melano-macrophage centers (MMCs), multiple cysts of nematode in hepatic tissue (incidental finding). The histopathological alterations of the kidney showed severe congestion of BVs, vacuolar degeneration of the renal tubular epithelium, severe interstitial mononuclear cell infiltration, and marked activation of MMCs in the kidney. Moreover, congestion of BVs and marked activation of melano-macrophages (MMCs) were found in the spleen. The MMCs of most of the sampled tissues showed a strong positive reaction for ferric iron. Conclusion: The polluted aquatic environment by sewage at Tripoli Coast is an essential factor for triggering the pathogenicity and invasion of Vibrios to vulnerable Atlantic horse mackerel. Also, this study is a preliminary step to give a baseline for further future studies on epidemiology and control of Vibrio infection in Libyan fish.

Marine pollution in the Libyan coastal area: Environmental and risk assessment.

A comprehensive assessment of the potential adverse effects on environment and human health generated by the inputs of chemicals from the most important Libyan petrochemical plant is presented. Ecotoxicological risk associated with the presence of As, Hg, Ni, Zn and PAHs in marine sediments is low or moderate, with a probability of toxicity for ecosystem <9% and <20% for heavy metals and PAHs respectively. However, surface sediments result strongly enriched in Hg and As of anthropogenic origin. Investigation of metals in fish allowed to assess potential risks for human populations via fish intake. Target hazard quotients values indicate potential risk associated to toxic metals exposure by fish consumption and lifetime cancer risk (TR) values highlight a potential carcinogen risk associated to As intake. Noteworthy, the presented results provide an unprecedented environmental dataset in an area where the availability of field data is very scant, for a better understanding of anthropogenic impacts at Mediterranean scale.