Are Sea Urchins Dangerous?
Sea urchins are part of the Echinoderma phylum and are found worldwide, in warm and cold salt waters. They inhabit both shallow, sandy spots, as well as deeper rocky waters. Coral reefs also provide perfect hiding places for sea urchins. They usually venture out at night to feed on algae and other food particles. Sea urchins vary from 3 to 10 centimetres in length and are covered in sharp "spines" which are designed to protect the urchin from predators, used while gathering food and also assists their movement in the water.
These spines vary in length, depending on the specific species. Some are short and blunt while others are long and dangerous filled with venom. Some spines are so long and sharp they can even pierce the skin through a wetsuit. If the skin of a diver is pierced by these spines, it can cause an extremely painful would. There are various different colour urchins, including black, red, purple brown and different shades of green.
Although most sea urchins are relatively harmless, some including the purple sea urchin have another form of protection as well. These are known as pedicellarines and resemble tiny claws which are hidden beneath the spines. If divers come in contact with the urchin, the claws can cling onto the skin while excreting a dangerous poison. Although a single wound would generally only administer a small amount of poison, multiple punctures can lead to symptoms such as dizziness, muscle spasms and shortness of breath. In extreme cases, the venomous wounds from certain sea urchins can even be fatal.
It is important to treat wounds appropriately. Divers can remove the pedicellarines by shaving the affected area with a razor and then washing and rinsing thoroughly with soap and fresh water. If necessary, an antibiotic cream can be used and analgesics should relieve the pain. These procedures should be adequate in dealing with the puncture wounds, but it is imperative that a doctor be consulted should the wounds become infected. Allergic reactions to the venom could result in chest pains or difficulty breathing.
The majority of spines can easily be removed with a simple pair of tweezers, but if any are broken off , especially near nerves or blood vessels (particularly, the hands and feet) rather get a doctor to remove them.
In certain diving conditions it may be difficult to avoid contact with urchins but divers need to be aware at all times. Try to keep a safe distance from coral where the urchins hide and look out for spines which may stick out from beneath the sand.
Fish, crabs, and birds all prey on sea urchins. In some countries, certain species are even served as a popular delicacy. Today, some species of sea urchin have populations that are considered to be threatened with extinction. This is mainly due to serious water pollution issues, as well as dredging on the ocean floor.
During a scuba dive, divers can safely delight in the spectacular array of sea urchins, inhabiting the waters below as long as they remain disciplined and cautious throughout the dive.