Abalones (Haliotis)

Abalone with a live sponge in its shell and a Green Snakelocks anemone during very low tide in January 14, 2013. Photo Pedro PVZ licensed under the Creative Commons.





These sea creatures cling steadfast to rocky surfaces with their broad, muscular foot, submerged by water in the sublittoral, though the Black abalone (Haliotis cracherodii) was common in the intertidal. Abalones reach maturity at a relatively small size. And when they’re adults they lay enormous amounts of eggs, the number increases with their body size – up to as many as 10.000 to 11 million eggs at a time. The larvae must take care of themselves from the beginning and soon search for hard surfaces to settle. The abalones are plant eaters and feed with their minutely toothed ribbon on macroalgae, preferring red or brown algae.


The shell of the abalone is exceptionally strong and is made of microscopic calcium carbonate tiles stacked like bricks. Between the layers of tiles is a clingy protein substance. When the abalone shell is struck, the tiles slide instead of shattering and the protein stretches to absorb the energy of the blow. Material scientists around the world are studying this tiled structure for insight into stronger ceramic products such as body armour.[1]

Abalones are one of the many classes of organism threatened with extinction due to overfishing and the acidification of oceans from anthropogenic carbon dioxide,[2] as reduced pH in the water erodes their shells. It is predictedt hat abalones will become extinct in the wild within 200 years at current rates of carbon dioxide production.[3] Today, the White (H. sorenseni), Pink (H. corrugata), and Green abalone (H. fulgens) are on the federal endangered species list.


The Abalones vary in size, like the "Most Beautiful Abalone" (Haliotis pulcherrima) ranging from 1.8 to 4 cm, while the Red abalone (Haliotis rufescens) is the largest

of the genus at 30 cm.[4]

1 Lin & Meyers 2005, p. 27 & 38: https://www.sciencedirect.com/science/article/abs/pii/S0921509304008809?via%3Dihub.

2 Byrne et al. 2011 https://royalsocietypublishing.org/doi/full/10.1098/rspb.2010.2404.

3 Ocean acidification https://ocean.si.edu/ocean-life/invertebrates/ocean-acidification.

4 Hoiberg, Dale H., ed. (1993). Encyclopædia Britannica. p. 7.