Cnidarian jellyfish are viewed as an emergent problem in several coastal zones throughout the world. Recurrent outbreaks pose a serious threat to tourists and bathers, as well as to sea-workers, involving health and economical aspects. As a rule, cnidarian stinging as a consequence of nematocyst firing induces merely local symptoms but cardiovascular or neurological complications can also occur...

mpirical research in behavioral ecolE ogy is dominated by studies of verte brates and insects. The journal Animal Behavior, for example, during the last half of 1995 (Vol. SO), had a total of 48 papers onmammals, 43 on birds, eight on amphib ians and reptiles, 17 on fishes, 33 on terrestrial invertebrates (primarily insects), and five on aquatic invertebrates (only two of which were marine). Th...

Intraspecific encounters between colonies of the athecate, colonial hydroid Hydractinia echinata result in contact between mat or stolonal tissues. We have monitored colony ontogeny in five clones of H. echinata and initiated experimental encounters between the two tissue types in both isogeneic and allogeneic combinations. All isogeneic interactions result in fusion, all allogeneic interaction...

A highly specific cellular recognition system, capable of distinguishing between syngeneic and allogeneic tissue, exists in Anthopleura elegantissima, a sea anemone that lives in clonal colonies and attacks foreign clones. During the attack, specialized surface protrusions (acrorhagi) are used for stinging. The recognition process was studied by presenting various tissues to the surface of infl...

Population connectivity resulting from larval dispersal is essential for the maintenance or recovery of populations in marine ecosystems, including coral reefs. Studies of species diversity and genetic connectivity within species are essential for the conservation of corals and coral reef ecosystems. We analyzed mitochondrial DNA sequence types and microsatellite genotypes of the broadcast-spaw...

Mass aggregations of the giant jellyfish Cyanea nozakii have occurred in China since the end of the 20th century. In particular, C. nozakii bloomed abnormally in Liaodong Bay during July and August of 2004 and the catch of edible Rhopilema esculentum was greatly reduced. In order to clarify the causes leading to mass occurrences of C. nozakii, the reproductive cycle and morphological characters...