Intertidal oyster reefs are thought to grow best when they are out of the water 20-40% of the time, but as reefs age, they tend to grow most rapidly when they are exposed about 50-60% of the time. Molly Bost recently published her first first-authored paper that presents those data, entitled “Natural intertidal oyster reef growth across two landscape settings and tidal ranges“. We mapped oyster reef growth over a three-year period, cored reefs, and radiocarbon dated the first oyster to colonize the sandflat. The radiocarbon date of that initial oyster represents the age of the reef. The oldest reef we sampled was 1395 years old!
The blue bars on this graph are showing the range of exposures encompassed by each reef we looked at in Back Sound, NC. The tops of the older reefs are high and out of the water up to 70% of the time. The red circles represent the aerial exposure where the reefs grow at their highest rate (cm/y) and that also increases as the reef ages. We continue to examine oyster reef growth with the aim of defining conditions where they grow best. This information will be used to help optimize the design of restoration projects.