• Sea urchins in their natural environmentaltrendo nature/Stockbyte/Getty Images
  
  Belonging to the animal class Echinoidea, sea urchins are spherical-shaped invertebrates covered with spiny shells that help them move about and protect them from predators. They live around the world in coral reefs, rock formations, beds of sea grass and kelp forests--their main source of food. They are omnivores, so they also consume algae, other types of seaweed and dead sea animals. Susceptible to change, sea urchin populations are easily affected by environmental dangers and the effects of harvesting. Harvesting sea urchins can also lead to several cons for the marine environment and other animals.
  
  

Prickly Spines

• Coming in contact with their spines is one con of harvesting sea urchins. The spines are capable of piercing the skin and breaking off inside. They may or may not contain venom, depending on the type of sea urchin, but will cause inflammation on your skin.
  
  

Rush for Food

• Sea urchins prepared as foodsea urchins image by Natalya Korolevskaya from Fotolia.com
  
  Sea urchins are harvested for their meat and eggs, or roe, which are very popular in Japanese sushi cuisine. The expense of the sea urchin's eggs is 100 times per pound of that of a mature sea urchin. Harvesting an urchin can bring about intense competition, which leads to over-harvesting and a depletion of the sea urchin population in a specific area.
  
  

Environmental Damage

• Damage to the marine environments of sea urchins is a con that takes a very long time to fix. Sea urchins are often harvested by sea urchin drags that sweep across the ocean floor. Harvesting them causes damage to the coral reefs that they live in. It also damages other marine life and plants that may be in the path of the sea urchin harvesting.
  
  

Dangerous Deep Dives

• Sea urchins form beds on the ocean floor. The deeper the floor, the more health dangers that divers face when they are harvesting sea urchins. This is especially true since sea urchins may no longer exist in the easy-to-reach areas due to over-harvesting.
  
  

Working with Regulations

• While working around regulations set by coastal states in the effort to preserve sea urchin populations is not a con in itself, it does indicate that the sea urchin population is a delicate and important part of the ecosystem that cannot withstand the damaging effects of harvesting. For example, the state of Maine sets several regulations. These define sea urchin conservation areas that are off limits to harvesting, specify the size and limits of using drags, limit the amount of harvesters each season through a lottery system, and limit the harvesting to a designated season.
  
  

Food Web Disruption

• Sea urchins are members of a food web that becomes disrupted when their populations are decreased. Sea urchins are a food source for sea otters, lobsters, crabs, sheephead fish, eels, other fish, birds and humans. If harvesting depletes the sea urchin population in an area, these other marine animals are left without a food supply. Conversely, sea urchins feed on kelp; when their populations are decreased by harvesting, kelp can grow abundantly and change the marine ecosystem of that area.