A question frequently asked by Scuba Divers is what are the toxic/stinging/hazardous coral and marine life you should avoid touching while Scuba diving? Most divers know and are aware of the toothy creatures to keep away from while diving, but often mistaken for harmless plants or nonliving gelatinous masses are marine invertebrates and coral that can cause allergic reactions, stings and often contain toxic venous substances that can cause severe injury to divers if encountered.
We have listed a few such hazardous creatures,and things to look out for when diving, which can cause serious harm to unaware or inattentive divers through contact. Essentially underwater contact irritants consist of any substance that when the skin comes in contact with a substance that acts as an irritant and causes contact dermatitis.
Although most sea sponges are harmless and contact results in minimal effects or abrasions, except for species that produce crinitoxins and can cause irritation and dermatitis. There are three species in particular which produce contact dermatitis; red-beard sponge (Micronia prolifera), fire sponge (Tedania ignis) and poison-bun sponge (Fibula nolitangere).
The red beard sponge has thick, intertwining branches that vary in color from bright red to orange and are abundantly found in the waters of northeastern United States
Fire Sponge named for the burning sensation and rash it produces when touched is large and usually Bright red or red-orange and lobed, and smooth, with few large pores. Found commonly in the Western Atlantic and Caribbean coastal waters, from Florida to Mexico; Bahamas and the West Indies.
You often feel nothing when you first touch a poisonous sponge. A burning, stinging, or itching feeling begins hours, or even days, after initial contact. Effects ranging from mild to severe pain, and local inflammation, redness, joint-pain and swelling may occur after touching a toxic sponge.
While most Sea Anemones are relatively harmless to humans, a few of them produce strong toxins that produce severe effects. Sea anemones are close relatives of jellyfish and corals and bear similar stinging tentacles. The most toxic of Anemones is the Actinodendron plumosum known as the stinging anemone or Hell’s Fire anemone due to its very painful sting. Found primarily in the indo-pacific ,these anemones that look more like soft coral with fir tree like/ leaf shaped or feather-like appearance branches, that possess nematocysts (tiny venous stinging cells) that cause pain, burning sensation and/or itching. The Hell’s Fire Anemone can be light yellowish green, tan, brown, light green or gray and can be recognized by its frilly or feathery appearance.
A fireworm which is a type of bristleworm is a bright orange and red colored flattened segmented worm, reaching 30cm in length, has of white bristles along each side. The bristles are hollow and venom-filled which easily penetrate the flesh and break off if this worm is touched. They produce an intense irritation in the area of contact, The fireworm is abundant on reefs, beneath stones in rocky or sea grass areas and on some muddy bottoms. It is found throughout the tropical western Atlantic.