Upwelling and the persistence of coral-reef frameworks in the eastern tropical Pacific, carbonate data, chlorophyll data, and others from 2015-08-15 to 2018-09-18 (NCEI Accession 0239049)

After two years in situ, the Porites blocks were collected and scanned using high-resolution computed tomography (CT) to volumetrically quantify both endolithic and epilithic habitat alteration. Scan-volumes were further classified into functional groups according to morphology to quantify external bioerosion by fish and sea urchins, as well as the calcifying and bioeroding activity of crustose coralline algae, scleractinian corals, mollusks, annelids, and barnacles.

The GoP, which has higher productivity, cooler temperatures, and periodically lower pH conditions, had higher rates of macroboring, but also higher rates of calcification. These unexpectedly higher rates of calcification in the GoP were a result of high recruitment of suspension-feeding taxa, particularly barnacles and vermetid gastropods that have poor reef-forming potential. External bioerosion by grazers was the dominant process influencing these dead coral substrates across both gulfs, ultimately contributing to higher rates of net erosion in the GoC and underscoring the important roles that urchins and fish play in not just removing algae on reefs, but also eroding reef habitat.

Ultimately these findings reveal that the trophic requirements of habitat-altering taxa are closely tied to reef-framework stability, and that environmental conditions conducive to carbonate precipitation are not necessarily those that will lead to habitat persistence.