The Gulf of Mexico oil spill this year and subsequent cleanup efforts could drive the world's smallest sea horse into extinction, warns the Zoological Society of London and its marine conservation organization Project Seahorse

The tiny dwarf sea horse (Hippocampus zosterae), which grows to a maximum length of 2.5 centimeters, can be found only in the ocean waters off the Gulf Coast.

"All of the sea horse populations in the area will be affected, but the dwarf sea horse is at greatest risk of extinction because much of its habitat has been devastated by the spill," Project Seahorse director Amanda Vincent said in a prepared statement.

According to Project Seahorse, the dwarf sea horse is particularly vulnerable due to its small size, limited habitat, inability to migrate great distances, and low birth rate. The fish also mate for life, so the loss of even one breeding parent is doubly dangerous to the species' long-term reproductive health. The Deepwater oil spill occurred during the sea horses' primary breeding time.

Another problem is that the dwarf sea horse, unlike its cousin sea horse species, often lives close to the ocean surface in floating mats of sea grass. Not only did spilled oil accumulate in these mats, BP burned many of them to prevent them from carrying oil onto the shore. According to Project Seahorse's press release, "The burning of the mats has killed many marine animals while depriving others of their habitat and exposing them to further toxicity. Sea grass is vital to the long-term health of coastal ecosystems, sheltering marine animals, acting as fish nurseries, improving water quality and preventing erosion."

Meanwhile, Project Seahorse experts also express fear that the dispersants used to treat the oil spill will add further toxicity to the dwarf sea horse's habitat.

Project Seahorse is calling on BP to use booms and skimming to remove the remaining oil in the Gulf. The method is more labor-intensive, but the group says it will cause less environmental damage to the species in the region.

Dwarf sea horses, also known as "pixies," are pricey acquisitions for aquarium enthusiasts. One site,, has them listed for $75 each and warns customers that they are "very delicate" and "for experts only."

Photo via Wikipedia.