Threats & Threats
Given that this species grows rapidly, is high fecund and repeated spawning throughout the year, there is no surprise that Cypraea annulus are common throughout the Indo-west pacific region, from East Africa to the Central Pacific Ocean. C. annulus and C. moneta (similar in size, shape and appearance) were collected and shipped Africa, India and China where they were used for currency for many centuries. These species were collected in the Maldives. By 1851 these cowries were so plentiful and inexpensive, that inflation resulted in thousands of shells having to be counted for a small purchase and whole cargo ships were dedicated to cowries. Today, this species is sold commercially despite it's relatively small value and has seen a rise in numbers over the past decades (Newton et al. 1993). This rise is correlated with increased fishing, coastal organic enrichment or competitive release as other cowries or competitors are removed (Newton et al 1993). However, the gold ring cowry could potentially be threatened by shell
over-collection, intensive fishing, natural predators, habitat destruction, pollution and trace metals (Hung et al. 2001), and climate
change.
The very narrow toothed aperture of the cowry shell makes the adult shells difficult for many predators to reach into. However cowries are still vulnerable to predation by crustaceans, cone shells and octopuses. Some tropical crustaceans are strong enough to break the cowry's shell while mollusc-eating cones digest the cowry by injecting venom and extending their stomach through the aperture. Some octopuses can also gouge small holes into the shell with their radula and or acid secretions.
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