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These structures are used in feeding and provide nutrients in combination with what is made available by the photosynthetic dinoflagellates. The medusa, the dominant adult phase of the life cycle, possesses four branching tentacles that extend from the body, up into the water column. This display is the result of numerous densely packed symbiotic zooxanthellae, Symbiodinium microadriaticum. Often it has a somewhat green or gray/blue coloration. The up-side down jellyfish does not have the typical physical characteristics of jellyfish.

Range depth Shallow Areas (low) m (low) ft.

( Berryman, 2005 Hofmann, et al., 1996 Kitt and Costley, 1998 Niggl and Wild, 2009) There were nearly none observed throughout the winter or spring. Numerous quantities of the benthic-dwelling ephyra and strobilating scyphistomae were observed from late June until the end of the fall season. Upside-down jellyfish most commonly use muddy substrata in mangrove leaves to settle upon, giving rise to the common name "mangrove jellyfish." The jellyfish are found during the mid to late summer with very few scyphistomae observed between late November and early June. ( Hofmann, et al., 1996 Kitt and Costley, 1998)Ĭassiopea xamachana frequently resides inshore in shallow, tropical, marine waters, on particular sandy mudflats. The highest density of these scyphozoans occurs in the Caribbean but throughout the course of the last decade the distribution seems to be expanding to other locations such as the Hawaiian and Mediterranean waters, including the Red Sea. They are commonly found in places such Walsingham Pond and Harrington Sound, on the bottom of an inshore bay or pond. This species is also found in Bermuda, the Caribbean Sea and warmer areas of the western Atlantic Ocean. The presence of Cassiopeia at the Gazi lagoon adds value to tourism attraction of the area.The northern distribution limit of Cassiopea xamachana is the southeastern tip of the United States as upside-down jellyfish appear in large numbers in varying areas of the Florida Keys. Future studies are recommended to determine factors that restrict the distribution of this species to a specific location at the south coast of Kenya. This study is significant in being the first study to document the population biology of the jellyfish at the Kenyan coast.

It is possible that clumping was also related to the size of the tidal pools. The smaller the individuals, the more likely they were to be found in clumps compared to larger individuals. Diameter appears to have been the single most factors that influenced spacing. If the diameter of the jellyfish correlates with the age, then the population structure of the jellyfish at Gazi Bay is that of a growing population. More individuals were found in clumps than singly more so where the sea grass dominated. Very few individuals occurred in the 12.0-12.9cm class. Most individuals had a mean diameter of 8.0-8.9 cm. Majority of the individuals were feeding. There were predominantly more light brown individuals followed by dark brown with the least number of individuals being grey. The percentage vegetation cover in each pool was estimated and recorded to the nearest whole number. Because jellyfish occurred in tidal pools, the number of individuals in each pool was determined. The colour and number of tentacles on each individual was determined and its activity at the time, recorded. For each individual jellyfish, the diameter was determined using a standard ruler. In each quadrat, all jellyfish encountered were sampled individually. A total of 1043 individual upside-down jellyfish were sampled.

Ten 50mx50m quadrats were randomly placed in an estimated study area of 6.4ha to cover about 40 percent of the total study area. The objective of this study was to quantify the spatial and size-class distribution, and recruitment of Cassiopeia at the Gazi Bay. There are no documented studies on this species in Kenya. In coastal Kenya, they are found only in one specific location in the Gazi Bay of the south coast.

They have a radial symmetry and occur in shallow, tropical lagoons, mangrove swamps and sandy mud falls in tropical and temperate regions. The medusa is the dominant phase in its life history. It is commonly referred to as jellyfish because of its jelly like appearance. Cassiopeia, the upside-down or mangrove jellyfish is a bottom-dwelling, shallow water marine sycophozoan of the phylum Cnidaria.