DOI: 10.5061/dryad.4qrfj6qkj
title: Effects of ocean acidification on the interaction between calcifying oysters (Ostrea chilensis) and bioeroding sponges (Cliona sp.)

description: Ocean acidification can negatively affect a broad range of physiological
 Q9 processes in marine-shelled mollusks. Marine bioeroding
 organisms could, in contrast, benefit from ocean acidification
 due to reduced energetic costs of bioerosion. Ocean acidification
 could thus exacerbate negative effects (e.g. reduced growth) of
 ocean acidification and shell borers on oysters. The aim of this
 study was to assess the impact of ocean acidification on the oyster
 Ostrea chilensis, the boring sponge Cliona sp., and their
 host-parasite relationship. We exposed three sets of organisms 1)
 O. chilensis, 2) Cliona sp., and 3) O. chilensis infested with
 Cliona sp. to pHT 8.03, 7.83, and 7.63. Reduced pH had
 no significant effect on calcification, respiration, and
 clearance rate of uninfested O. chilensis. Low pH significantly reduced
 calcification leading to net dissolution of oyster shells at pHT
 7.63 in sponge-infested oysters. Net dissolution was likely caused by
 increased bioerosion by Cliona sp. at pHT 7.63. Additionally,
 declining pH and sponge infestation had a significant negative
 antagonistic effect (less negative than predicted additively) on
 the clearance rate. This interaction suggests that sponge-infested oysters
 increase clearance rates to cope with the higher energy demand of
 increased shell repair resulting from the higher boring activity of Cliona
 sp. at low seawater pH. O. chilensis body condition was unaffected by
 sponge infestation, pH, and the interaction of the two. The
 reduction in calcification rate suggests sponge infestation and
 ocean acidification together would exacerbate direct (reduced
 growth) and indirect (e.g., increased predation) negative
 effects on oyster health and survival. Our results indicate that
 ocean acidification by the end of the century could have severe
 consequences for marine mollusks with boring organisms.
description: # Effects of ocean acidification on the interaction between calcifying
 oysters (Ostrea chilensis) and bioeroding sponges (Cliona sp.)
 [https://doi.org/10.5061/dryad.4qrfj6qkj](https://doi.org/10.5061/dryad.4qrfj6qkj) ## Description of the data and file structure Effects of ocean acidification on the interaction between calcifying oysters (Ostrea chilensis) and bioeroding sponges (Cliona sp.) Dataset contains: \- Long-term calcification/bioerosion rates from buoyant weight normalised for tissue dry weight and time and corrected for weight loss of control samples (oyster_shells) in sheet “Net_calc&Net_bioer” \- Long-term calcification rates from buoyant weight normalised for tissue dry weight and time in sheet “Calc&Bioer_uncorrected” \- Respiration rate from incubations normalised for tissue dry weight and time in sheet “Respiration_rate” \- Clearance rate of different particle sizes (&gt;5-60um,2.5-60um,2.5-5um) normalised for tissue dry weight and time in sheet “Clearance_rate” \- Short-term calcification and chemical bioerosion rates from incubations normalised for tissue dry weight and time in sheet “Short-term_calc&chem.bioerosion” \- Conidtion index in sheet “Condition” The data derives from specimen of the category uninfested oysters (Ostrea chilensis), sponge infested oysters (Cliona sp. & Ostrea chilensis) and sponges (Cliona sp.) that were exposed to three different pH levels. Each sheet within the set contains: \- The sample/specimen ID and category (in column “ID” and column “Category” both given as character) \- Treatment information (exposure to pHT level 0f 8.03(amb), 7.83(fut1), 7.63(fut2), with daily variability of ±0.1 units) \- Information regarding different tanks used for housing, water supply (experimental tanks in column “Tank”; header tanks in column “Header” and water bath used to house experimental tanks in column “Waterbath”; all given as character) In addition to the above information each sheet contains sheet specific columns and information: \- Sheet “Net_calc&Net_bioer” contains calcification rate (in mg normalised for surface area and time in days and corrected for weight loss of control samples) \- Sheet “Calc&Bioer_uncorrected” contains calcification rate (in mg normalised for surface area and time in days) \- Sheet “Respiration_rate” contains respiration rates (in mg oxygen normalised for tissue dry weight and time in hours) \- Sheet “Clearance_rate” contains clearance rate (in L normalised for tissue dry weight and time in hours) \- Sheet “Short-term_calc&chem.bioerosion” contains short-term calcification and chemical bioerosion rates (in mmol normalised for tissue dry weight and time in days) \- Sheet “Condition” contains condition index (calculated by dividing tissue dry weight by shell dry weight and multiplying with 100; uninfested oysters and sponge infested oysters only)