Oyster Biology and Reef Ecosystems Practice

This set of vocabulary flashcards covers oyster development, buoyancy stages, growth rates, and ecological interactions within a reef environment as described in the lecture.

Spat

The stage of young oysters once they have developed thin shells and are ready to settle and attach to a surface.

Exoskeleton

The external skeleton that a crab develops, which causes its body to become heavier.

Negatively buoyant

The state where an organism's body becomes heavy enough to sink to the bottom, which is necessary for an oyster to land on a reef or piling.

Neutrally buoyant

The transitional state of buoyancy where an organism is neither sinking nor floating before it becomes negatively buoyant.

Umbo area

The specific part of the oyster shell, traditionally associated with the secretion of the glue used to adhere to other shells or surfaces.

Terminal molts

The final shed shells of crabs or horseshoe crabs that baby spat sometimes use as a surface for attachment.

Attrition rate

The measurement of how many offspring die; in oysters, this is a huge number even when billions of offspring are produced.

$$1\,\text{inch a year}$$

The approximate rate at which an oyster shell grows.

Hydroids

A type of organism mentioned as part of the diverse community of species, including algae and barnacles, that live on oyster clumps.

Yabby pump

A device used in conjunction with a sieve box to search for worms in the sediment.