Sunday, 22 May 2016

Queen Conch

Lobatus gigas juvenile covered with algae & sediment at Old Sweat Bank, Florida Bay- Photo Credit: Dr. Joshua Voss
Lobatus gigas, otherwise known as the Queen Conch, is a gastropod species that is native to the tropical Atlantic Ocean. The Queen conch is a mollusc that can grow to have a shell size of nearly 14 inches in length. They produce a dextral, spiral shell with several protrusions and spikes around the base of the topmost spire as well as off of the individual whorls themselves. In mature shells, the outer lip of the shell flares outward, a feature that is absent in juvenile shells. This lip is actually an adaptive advantage for the species, as it makes it nearly impossible to roll them over via oceanic or tidal currents. The inside of the shell has a smooth, polished appearance with a soft pink and orange coloration, while the outside of the shell is more rough and inconspicuous in color.

These creatures largely inhabit seagrass beds, and are largely found at depths between 1-18 meters. A pattern has also been observed that individuals tend to inhabit deeper and deeper waters as they grow older. Queen conches are herbivorous, feeding mainly on red and green macroalgae and seagrasses. They can be found both in aggregations or solitary. These molluscs are also an important prey species for several other gastropods including the horse conch (Pleuroploca gigantea), the tulip snail (Fasciolaria tulipa), moon snails (Natica spp.), and other marine invertebrates like the blue crab (Callinectes sapidus) and the spiny lobster (Panulirus argus). Almost all of these top predators were found in the Florida Bay, where a queen conch was originally spotted on this trip.
 
A horse conch at the Keys Marine Laboratory, an important predator of Queen Conches - Photo Credit: Corey Corrick 

One of the Spiny Lobsters spotted at Koch Key, FL: another predator of Queen Conches - Photo Credit: Dr. Voss
Queen Conches are currently considered commercially threatened and overfished due to illegal harvesting and their very low replacement rates. They are protected under CITES (Convention of International Trade in Endangered Species) through which their harvesting and trade is regulated. Queen Conch is harvested commercially by humans for food, marine chum and bait, tourist souvenirs, and jewelry (particularly the very elusive conch pearls that their mantles sometimes produce). Currently conservation efforts are underway to preserve this species, as population declines of nearly 80% have been observed within the last two decades alone.

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