Abstract

The Mediterranean Sea is home to many species of jellyfish, both native and invasive, some of which may be harmful to humans. This descriptive study aims to identify the jellyfish species present in the marine ecosystem of the Gaza Strip, Palestine. The study spanned a period of 15 years starting from 2010. Frequent field visits, meetings and discussions with stakeholders, keeping up with local media reports, videos, social media and photography were essential tools for conducting the current study. The study recorded six species of jellyfish belonging to five families and two orders of the Scyphozoa class in the coastal waters of the Mediterranean Sea and the sandy beaches of the Gaza Strip. The coming years may witness the recording of more jellyfish species. The species recorded were the Barrel Jellyfish (Rhizostoma pulmo), the Nomadic Jellyfish (Rhopilema nomadica), the Australian Spotted Jellyfish (Phyllorhiza punctata), the Mediterranean Jellyfish (Cotylorhiza tuberculata), the Purple Jellyfish or Mauve Stinger (Pelagia noctiluca) and the Common or Moon Jellyfish (Aurelia aurita). Two of the recorded species are invasive. Among the recorded species, the Barrel Jellyfish and the Nomadic Jellyfish are the most common in marine waters and on beaches and at the same time they are the most stinging and toxic to Gazans. Every summer, thousands of Gazans are stung by jellyfish while swimming or relaxing on the 42-kilometre-long beach, forcing some to go to hospitals, although the majority of Gazans resort to well-known local recipes to treat jellyfish stings. Many stakeholders claimed that climate change, by-catch of jellyfish enemies, overfishing, Lessepsian migrations, pollution, and nutrient abundance (eutrophication) are all combined factors that promote local jellyfish blooms. In conclusion, public awareness of the dangers of jellyfish on the Mediterranean coast of the Gaza Strip is necessary and important, and lifeguards and first aid workers must be trained to deal with cases of poisoning by jellyfish and possibly other marine organisms.

Keywords:Scyphozoa; Rhopilema nomadica; Lessepsian migrants; native vs. invasive; Jellyfish stings; Mediterranean Sea; Gaza Strip.

Introduction

Jellyfish are some of the most beautiful in the world that belong to the phylum Cnidaria (Coelenterata) or stinging creatures, which includes, in addition to jellyfish (class Scyphozoa), anemones and corals (class Anthozoa), box jellies (class Cubozoa), and hydras (class Hydrozoa) [1]. Members of the phylum Cnidaria are characterized by radially symmetrical bodies with two layers of tissue (endoderm and ectoderm) separated by a variably filled mesoglia, and a diffuse, net-like nervous system lacking any form of centralization [2] Jellyfish have umbrella-shaped bells and pendulous tentacles. The bell can pulse to provide propulsion for efficient locomotion. The tentacles are armed with stinging cells (cnidoblasts or cnidocytes) containing a structure called a nematocyst. Nematocysts, which are coiled, thread-like stingers, are formed and used only by cnidarians to capture and immobilize preys and to defense against predators [3]. Jellyfish have a complex life cycle. They are usually in the sexual stage, which produces planula larvae. They then disperse widely and enter a stable polyp stage that may include asexual budding before reaching sexual maturity. Jellyfish are considered a delicacy in some Asian countries, where some species are squeezed and salted to remove excess water. Some scientists have considered them an ideal food because they are rich in protein and relatively low in dietary energy [4-8].

The Mediterranean Sea is home to many species of jellyfish, both native and invasive, some of which can be harmful to humans [9]. According to several publications [10-17], the species of jellyfish in the Mediterranean Sea include the Common or Moon Jellyfish (Aurelia aurita), Barrel Jellyfish (Rhizostoma pulmo), Mediterranean Jellyfish (Cotylorhiza tuberculata), Compass Jellyfish (Chrysaora hysoscella), Purple Jellyfish or Mauve Stinger (Pelagia noctiluca), Blue or Blue-fire Jellyfish (Cyanea lamarckii), etc. The Nomadic jellyfish, an invasive and dangerous species, entered the Mediterranean Sea via the Suez Canal in the 1970s and has rapidly spread throughout the Mediterranean [18-20].

The distribution of jellyfish is commonly influenced by many factors such as climate, sea conditions, water temperature, and nutrient level [21]. They feed on small marine organisms such as plankton. Jellyfish are most common in the Mediterranean Sea during the warmer months, e.g., during the summer months when water temperatures are higher and there is more sunlight for plankton to grow and feed on. As far as jellyfish stings are concerned, the sensations of a jellyfish sting can vary depending on the species of jellyfish and the immune system of the person who was stung. Symptoms may include pain, swelling, and redness at the site of the sting, and possibly an allergic reaction. Some jellyfish that reach shore are still capable of stinging if handled, even after several days of drying [22].

Despite the many regional studies that have addressed the species of jellyfish found in the Mediterranean Sea and their risks to the public health of divers, swimmers and vacationers [23-41], scientific literature on jellyfish species that roam the Mediterranean waters of the Gaza Strip or wash up on its sandy beaches seems limited and very few. This can of course be attributed to the lack of specialists in marine biology, as well as the lack of interest of environmental and health institutions in toxic or dangerous marine organisms, despite their abundance.

Abd Rabou [42-45] reported that the Ocean Sunfish (Mola mola) and different species of sea turtles are considered a formidable enemy of jellyfish species in the marine ecosystem of the Gaza Strip, especially the Nomadic Jellyfish, which is an invasive species and causes toxic stings to vacationers, swimmers and sunbathers. [46] discussed the phenomenon of the very dense spread of the Purple Jellyfish (Pelagia noctiluca) along the beach in the Gaza Strip in 2014. [47] prepared a video of about three minutes showing four species of jellyfish thriving in the marine ecosystem of the Gaza Strip, without details about their names or classification [48] pointed out that four jellyfish species visit the calm water off Gaza’s shores and they range in color from white to red and blue.

Knowing the species of jellyfish in the waters and beaches of the Mediterranean Sea in the Gaza Strip remains a special priority for scientific, medical and environmental circles and the entire Palestinian society because these creatures are one of the components of marine biodiversity and Gazans are constantly exposed to their stings while swimming, surfing and sailing. It is worth noting that the marine environment is the only refuge and outlet for the Gazans who live in a very bad political, military, economic and social atmosphere due to the Israeli occupation of the Gaza Strip since 1967. Hence, the main objective of this study is to identify the species of jellyfish that have been observed, caught or by-caught from the marine ecosystem of the Gaza Strip or that have drifted or been washed up by waves to its sandy beaches. The importance of this modest study lies in the fact that it is the first in Palestine to investigate the diversity of jellyfish in the marine ecosystem of the Gaza Strip.

Methodology

The Gaza Strip

The Gaza Strip is an arid to semi-arid strip of Palestinian territory along the southeastern Mediterranean Sea (Figure 1), with an area of approximately 365 km2 [49], and a current population of approximately 2.4 million, the majority of whom are refugees who were expelled by Israel from the occupied Palestinian territories to live in camps called Palestinian refugee camps, which number eight in the Gaza Strip. The Gaza Strip is one of the most densely populated areas in the world [50]. The length of the Palestinian coastline in the Gaza Strip on the Mediterranean Sea is approximately 42 km. The Gaza Strip has a beautiful sandy beach that attracts tourists and vacationers from all over the Gaza Strip. The marine ecosystem in the Gaza Strip is home to a remarkable diversity of marine vertebrates and invertebrates [51], including jellyfish, which are the subject of this study.

Procedure

The present study is descriptive in its approach, extending over a period of 15 years starting from 2010. During this long period of time, frequent field visits were made to the coast of the Gaza Strip. Meetings and discussions were held with employees of the General Directorate of Fisheries Resources of the Ministry of Agriculture, fishermen, and dermatologists in the Gaza Strip to fill the necessary gaps in collecting data related to jellyfish and their stings in the Gaza Strip. In addition, local media reports and videos and social media related to jellyfish were tracked. During the study, several sources were used to identify and classify jellyfish [52]. Finally, cameras were used throughout the study period and photographs were taken for documentation and verification purposes. Some of the images were extracted from videos of jellyfish in the marine ecosystem of the Gaza Strip, and others were taken from various websites, including Palestinian news websites.

Results

The present study is a descriptive work spanning 15 years. The study recorded six species of jellyfish belonging to five families (Rhizostomatidae, Mastigiidae, Cepheidae, Pelagiidae, and Ulmaridae) and two orders (Rhizostomeae and Semaeostomeae) of the class Scyphozoa (true jellyfishes or true jellies or cup animals) in the Mediterranean coastal waters and sandy beaches of the Gaza Strip (Table 1). Of course, the coming years may witness more records of jellyfish species. The present study dealt with jellyfish that were observed at sea, caught or by-caught in fishing gear, or stranded on the beach in the Gaza Strip. These species of jellyfish; especially the Nomadic Jellyfish and Barrel Jellyfish or Dustbin-lid Jellyfish, which are mostly found in the summer, represent a clear threat to Gazans, as Gazans are stung by their toxic stings while swimming and sometimes while relaxing on the beach. Although most of the stung patients in the Gaza Strip do not reach hospitals or clinics, the number of cases of jellyfish stings is estimated to be in the thousands each year.

Recorded Jellyfish species in the Gaza Strip Barrel or Dustbin-lid Jellyfish (Rhizostoma pulmo Macri, 1778)

The Barrel Jellyfish has a large, transparent, bluish-white bell and is distinguished by the violet edge of the medusa (Figure 2A & 2B). The jellyfish does not have tentacles, but has 8 fused, branchless oral arms that contain small stinging tentacles. These giant jellyfish congregate in the coastal waters of Palestine and often wash up on the beaches of the Gaza Strip by the hundreds in early summer. The jellyfish is moderately venomous, but not as deadly as other species. Effects include a burning sensation on the skin, dermatitis, and ulcers, confirming that it is venomous to humans. However, it does not pose a serious threat to humans.

Nomadic Jellyfish (Rhopilema nomadica Galil, 1990)

The Nomadic Jellyfish is a tropical jellyfish native to the Indo- Pacific Ocean. It is characterized by its bright blue body and round bell (Figure 2C). This species is large compared to other local jellyfish species, as it can reach a diameter of 40-60 cm and a weight of 6 to 8 kg or more. Hundreds of this jellyfish are usually seen on the beach of the Gaza Strip, sometimes in good condition and other times in poor condition due to dryness and deformity. This species has caused the largest number of poisoning cases along the Palestinian coast of the Gaza Strip, where several hospital admissions have been reported annually due to poisoning from this jellyfish and other species. Along with the preceding species, the spread of Nomadic Jellyfish threatens recreation on the beaches, because its swarms limit the visits of Gazans to the beach and reduce swimming in the coastal waters as well.

Australian Spotted or White-spotted Jellyfish or Floating Bell (Phyllorhiza punctata Lendenfeld, 1884)

The Australian Spotted Jellyfish or the Floating Bell is an invasive species to the Mediterranean Sea as its name dictates. It is native to the southwestern Pacific Ocean where the Australia continent and Japan are located. This species has spread widely in other places, including the Mediterranean Sea, as indicated by many scientific studies that recorded its occurrence, sometimes for the first time. In fact, it is rare to see specimens of this species stranded and thrown on the beach in the Gaza Strip, but tours by skilled Gazan divers have shown its presence in noticeable numbers in the coastal sea waters of the Gaza Strip (Figure 2 D & 2E). The bell of this species was estimated to reach 40-50 cm or more in diameter. Like all jellyfish, the Australian spotted jellyfish has tentacles equipped with stinging cells or nematocysts that sting, but they are not considered dangerous to humans.

Mediterranean or Fried Egg Jellyfish (Cotylorhiza tuberculata Macri, 1778)

As the name suggests, the Mediterranean Jellyfish is common in the Mediterranean and adjacent seas. This jellyfish has a prominent, smooth central dome above its flat bell, which is why it is called the Fried Egg Jellyfish because of its striking resemblance to a plate filled with a fried egg with the yolk in the middle (Figure 2F & 2G). The oral arms are short and braided only at their base, and have an excessively curly lower part. The tentacles are short with violet tips. It is considered one of the most beautiful jellyfish species in the Mediterranean waters of the Gaza Strip. It is usually found in the surface waters, especially in July and the following months. The species is not large in size, and can reach a diameter of 20 - 30 cm or more. This jellyfish sting does not affect humans much, meaning that its sting is very mild or inoffensive to humans, but it may cause an allergic reaction in some people, including itching and scratching in the area affected by the sting.

Purple Jellyfish or Mauve Stinger (Pelagia noctiluca Forsskål, 1775)

The Purple Jellyfish or Mauve Stinger is known as the most poisonous jellyfish in the Mediterranean Sea. The Purple Jellyfish is a rare visitor to the Mediterranean waters of the Gaza Strip. The spring of 2014 brought incredible numbers, estimated at hundreds of thousands or even millions, of this unwanted guest to the Gaza Strip. Along the coast of the Gaza Strip, the density of this toxic species was estimated at about eight individuals per square meter. Palestinian fishermen and experts working in the General Directorate of Fisheries confirmed that the swarms of Purple Jellyfish that completely flooded the beaches of the Gaza Strip in 2014 are a rare phenomenon (Figure 3A). They also expressed their fear that the Purple Jellyfish will settle in the open marine environment, which will negatively affect tourists, swimmers and vacationers who frequent the sandy beaches in the summer due to the risk of being stung by these venomous jellyfishes. At that time, several Gazans reported being stung by this rare jellyfish even when they were dead and lying on the beach.

Common or Moon Jellyfish (Aurelia aurita Linnaeus, 1758)

The Common Jellyfish is transparent in nature and can be easily recognized by its four gonads located at the top of its bell. Although they are rarely seen in sea water or on the beaches of the Gaza Strip, they are difficult to photograph them well on the beach because the sand often sticks to their gelatinous substance, they dry easily, and they tend to look dull, and many of their features are flawed and appear blurry. In light of this, images from the Internet were used for clarification. (Figure 3B). The species can exceed 20 cm in diameter, and is characterized by its limited movement and can be carried by the current even when swimming. The Common Jellyfish has hundreds of short, thin tentacles on the edge of its bell, and its stings are minimal to humans.

Factors contributing to jellyfish abundance in the Gaza Strip

According to discussions with the General Directorate of Fisheries at the Ministry of Agriculture, many fishermen and other scientific forums, there are several factors associated with the spread or outbreak (swarming or blooming) of jellyfish species on the Mediterranean coast of the Gaza Strip, including:
1. Rapid global climate change is leading to increased jellyfish occurrence and spread. This increase can hamper fishing because fishing nets become contaminated with jellyfish.
2. Catch or by-catch of marine animals that feed on jellyfish, such as Ocean Sunfish (Mola mola) and sea turtles. It is worth mentioning that three species of sea turtles have been recorded in the marine waters or beaches of the Gaza Strip during the past decades. They include: the Loggerhead Sea Turtle (Caretta caretta), the Green Sea Turtle (Chelonia mydas), and the Leatherback Sea Turtle (Dermochelys coriacea).
3. Increasing pollution of the beach and sea water in the Gaza Strip with plastic waste, as sea turtles, the main enemy of jellyfish, are deceived by transparent nylon bags filled with water, and swallow them thinking they are jellyfish, which leads to blockage of their digestive tract, suffocation and inevitable death. In addition, the spread of damaged fishing nets in the open sea causes sea turtles to become entangled in them, suffocate and die.
4. The Lessepsian migration of marine organisms across the Red Sea and the Suez Canal from the Pacific and Indian Oceans, The Nomadic Jellyfish, the most dangerous and widespread in the Mediterranean, is a clear example.
5. Decrease in fish species due to overfishing that prevails in the coastal marine ecosystem of the Gaza Strip to the point of creating a vacuum in the marine environment that is filled with jellyfish. In other words, overfishing allows jellyfish to take over niches once occupied by other species.
6. Abundance of nutrients due to multiple pollutants that are dumped into the Mediterranean ecosystem of the Gaza Strip, which contribute directly or indirectly to the spread of jellyfish. It is worth noting that most of the raw or partially treated sewage produced in the Gaza Strip is discharged into the Mediterranean Sea through pipes and pumps, causing pollution of the marine environment.

How do Gazans deal with jellyfish stings?

The Mediterranean Sea is the only outlet for the Gazans, who have been suffering from the Israeli siege or blockade for seventeen consecutive years. Therefore, tens of thousands of Gazans resort every day in the summer to swimming in the sea or relaxing on the golden sandy beach, where many resorts, chalets, cafeterias and street vendors are spread, and they spend happy and enjoyable times. However, the spread of different species of jellyfish in the summer and in large numbers along the coast of the Gaza Strip spoils the mood of vacationers and deprives them of the opportunity to enjoy swimming and relaxing in hot weathers. There are no signs warning vacationers about the presence of jellyfish along the beach in the Gaza Strip, so Gazans who have been stung by jellyfish resort to well-known local recipes such as rubbing the sting site with beach sand, salt or vinegar and then washing the area with cold water. The person who is stung by a jellyfish feels as if fire is blowing at the site of the sting, then he/ she begins to scratch the site of the sting hysterically, which causes the site to gradually turn dark red as if it has been burned.

Because of the terrible pain caused by jellyfish stings and sometimes the ineffectiveness of local recipes for treatment and pain relief, some people go to the hospital for treatment, where doctors usually treat the sting as a first-degree burn. According to interviews with Gazans who were stung by jellyfish, their injuries last for days, sometimes from one to two weeks and sometimes longer. Some Gazans believe that marine rescuers should have a role in identifying the locations of jellyfish, warning about them, and providing first aid for their stings, and not leaving the matter to the judgment of Gazans, which often leads to counterproductive results. Some of the dermatologists interviewed said that the basic procedure for jellyfish stings is to remove the jellyfish tentacles with special tweezers, then wash the sting site with saline solution before transporting the patient to the nearest health center for the necessary treatment. They pointed out that the matter is not as simple as how Gazans deal with stings, as some cases may develop into high-risk infections, leading to unexpected results, especially with children and the elderly.

Discussion

The present study recorded six species of Scyphozoan jellyfish in the marine ecosystem and sandy beaches of the Gaza Strip. The coming years may witness the recording of more species of jellyfish because there are many species of jellyfish in the Mediterranean Sea and Mediterranean countries are constantly recording the occurrence of new species that may be indigenous (native) or invasive (exotic or alien). In fact, there are several studies in Mediterranean countries that have recorded for the first time new species of invasive jellyfish coming from the Indo-Pacific Ocean via the Red Sea and the Suez Canal (Lessepsian migrants), the Strait of Gibraltar or other routes [53-56]. The six species of jellyfish recorded in the Gaza Strip are among the species recorded in the Mediterranean and those recorded in countries close to the Gaza Strip [57]. Fortunately, studied jellyfish on the Mediterranean coast of El Arish, Egypt, an area only 30-40 km south of the Gaza Strip. The species recorded in his study are more or less close to those recently recorded in this study. It is worth noting that there are no new invasive species of jellyfish in the marine waters of the Gaza Strip other than those recorded in the eastern Mediterranean. Of course, the coming years may witness the recording of new invasive species, especially since the Gaza Strip is very close to the Suez Canal’s discharge into the Mediterranean Sea.

The Barrel Jellyfish is one of the common and largest jellyfish in the marine ecosystem of the Gaza Strip and the Mediterranean Sea as a whole [58,59]. Locally, this jellyfish is one of the most common to be washed up on the beach in the summer season and is easily identified by the purple edge or violet fringe of its bell. This argument is consistent with studies in areas close to the Gaza Strip [60]. Like other jellyfish, the Barrel Jellyfish’s sting is not very dangerous to humans [61], but when it washes up on the beach as it does in the Gaza Strip, it is better for Gazans not to handle it because it is still capable of stinging even when dead (Special communications). In fact, jellyfish stings are widespread throughout the world and cause a wide range of clinical manifestations and vary in severity depending on the species [62,63]. Jellyfish stings often cause immediate pain and signs of inflammation on the skin. Some stings can cause a whole-body (systemic) illness. In rare cases, they can be life-threatening [64- 66]. For example, Al-Rubiay et al. reported cutaneous and systemic manifestations due to Barrel Jellyfish stings in Iraqi fishermen.

Similar to the previously discussed Barrel Jellyfish, the Nomadic Jellyfish is also one of the common and largest jellyfish (40-60 cm or more) in the marine ecosystem of the Gaza Strip. In fact, this Lessepsian alien Nomadic Jellyfish is considered one of the worst marine alien or invasive species in the waters of the Mediterranean Sea [67-70]. It was first reported in the Mediterranean Sea in the mid-1970s. It has since extended its range successively to the coasts of other Mediterranean countries [71-74]. The species cause extremely painful stings among Gazans and pose a clear danger to swimmers, with several hospitalization cases reported annually, although most Gazans who suffer from stings receive treatment on the beach and never need to be hospitalized. In fact, several cases of hospitalization, and sometimes severe allergic reactions, have been reported after poisoning by Nomadic Jellyfish in various coastal countries [75].

The Australian Spotted Jellyfish shares with the Nomadic Jellyfish the fact that they are both invasive species in the Mediterranean Sea, as well as their relatively large size. It presents in the marine ecosystem of the Gaza Strip in noticeable numbers. This species has been confirmed in coastal waters of El-Arish and Port Said in Egypt, the country neighboring the Gaza Strip. According to Galil et al [76], this beautiful and striking species first appeared in the Mediterranean Sea off the coast of Israel in 1965. Since then, it has been reported in many coastal waters along the Mediterranean either as a few specimens or more recently as swarms [77-79]. The stings from this jellyfish’s tentacles are not considered dangerous to humans as claimed by local swimmers and divers. The Australian spotted jellyfish may not pose a threat to human health or tourism because it does not cause a painful sting however, it has already seriously affected fisheries in global locations such as the Gulf of Mexico [80].

Because of its imposing appearance, the Mediterranean or Fried Egg Jellyfish is a species endemic to the Mediterranean region, and is considered one of the most beautiful jellyfish in the Mediterranean waters. Because of its short tentacles, the stings of this jellyfish are considered mild and do not affect humans much. According to [81], Mediterranean Jellyfish does not have a strong sting, but it may cause discomfort by causing mild itching if it comes into contact with sensitive skin and mucous membranes. In the Gaza Strip, these harmless species may cause problems for swimmers when seen in large numbers in coastal waters, and may also cause a delay in tourism, similar to other recorded jellyfish species.

Although the Purple Jellyfish or Mauve Stinger is the most famous in the Mediterranean, it is very rare in the marine waters of the Gaza Strip. The blooming of this species and its presence in millions on the beach of the Gaza Strip in April 2014 was a strange event that the Gazans had never witnessed before. This dangerous species of jellyfish has flourished in many countries along the Mediterranean coast, causing painful stings to humans and sometimes losses to aquaculture and fisheries [82]. The presence of this species in the marine waters or on the beach caused painful but non-fatal stings to dozens of swimmers in the sea or vacationers on the beaches. According to Morabito et al. [83,84] the Purple Jellyfish is one of the most dangerous jellyfish in the Mediterranean Sea, and its venom can cause redness, swelling, dermoscopic features and blisters, in addition to constant pain at the site of the sting. Fortunately, this jellyfish was a visiting guest and did not stay long in the waters of the Gaza Strip; otherwise, the Gazans would have suffered from its serious dangers. Unfortunately, the unique and distinctive phenomenon of the 2014 Purple Jellyfish bloom on the coast of the Gaza Strip has not been scientifically studied due to the lack of marine biologists and the weakness of technical aspects and requirements for marine studies.

Although it is a cosmopolitan scyphozoan species, the Common or Moon Jellyfish is rare along the Mediterranean coast of the Gaza Strip as well as the entire coast of Palestine. Despite its local rarity, this jellyfish is probably the most studied in the world due to its universality, as indicated by [85,86]. The species differs from many Mediterranean jellyfish in that it lacks long, powerful stinging tentacles. For this reason, Common Jellyfish stings are considered mild and most people do not have any reaction to them, i.e. their stings are generally harmless to humans. Despite its very low toxicity, the large numbers of this species found in the Suez Canal of Egypt during the spring and fall cause serious problems for net fishing [87,88].

The factors that contribute to the spread of jellyfish regardless of their species are not far from those mentioned in other publications because the Mediterranean environment is more or less the same although sometimes different from the east to the west. Eutrophication, climate change, pollution, overfishing, alien invasions and habitat modification have been suggested by [89] as possible important contributory factors of jellyfish blooms. In the same context, and suggested that human or anthropogenic influences are possible factors behind population increases and geographic expansions of jellyfish in marine environments, including global warming, eutrophication, overfishing, bottom trawling, mariculture, and increased coastal development. Incidental catch of jellyfish enemies such as Ocean Sunfish (Mola mola) and sea turtles may contribute to the spread of jellyfish in the marine environment of the Gaza Strip. Plastic waste also harms sea turtles when they swallow nylon bags thinking they are jellyfish, leading to suffocation and death. Such concern was highlighted in previous local studies [90,91]. In this regard, Garcês and Pires [92] stressed that plastic pollution in marine environments around the world has harmful effects on all marine wildlife, especially sea turtles, which are facing death because of it.

As for jellyfish stings, it is recommended to avoid touching or getting close to jellyfish, even if they appear inactive or have washed up on the beach. Some species can still sting even when stuck on the beach. Also, it is recommended after jellyfish stings to protect the affected area and not to rub the sand, press on the area or scrape the sting site as these measures may activate jellyfish stings. The toxicological symptoms and risks that jellyfish stings of all kinds bring to Gazans and humans all over the world are numerous, as has been shown by many studies in different regional and international countries [93-97]. Much effort can be made to mitigate the severity of jellyfish stings in the Gaza Strip in order to avoid the toxic symptoms and risks that may affect swimmers, divers and vacationers. In general, public awareness of the dangers of jellyfish, especially the poisonous species, on the Mediterranean coast of the Gaza Strip is necessary and important, and lifeguards and first aid workers must be trained to deal with cases of poisoning by jellyfish and perhaps other marine organisms such as the Silver-Cheeked Toadfish (Lagocephalus sceleratus) which was caught from the marine ecosystem in the Gaza Strip and caused severe poisoning and deaths [98,99].

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