Biological Response

NOAA's Ocean Acidification Program supports research that focuses on economically and ecologically important marine species. Research of survival, growth, and physiology of marine organisms can be used to explore how aquaculture, wild fisheries, and food webs may change as ocean chemistry changes.


A number of NOAA National Marine Fisheries Service Science Centers have state-of-the-art experimental facilities to study the response of marine organisms to the chemistry conditions expected with ocean acidification.

The Northeast Fisheries Science Center has facilities at its Sandy Hook, NJ and Milford, CT laboratories; the Alaska Fisheries Science Centers at its Newport, OR and Kodiak, AK laboratories; and the Northwest Fisheries Science Center at its Mukilteo and Manchester, WA laboratories. All facilities can tightly control carbon dioxide and temperature. The Northwest Fisheries Science Center can also control oxygen, and can create variable treatment conditions for carbon dioxide, temperature, and oxygen. These facilities include equipment for seawater carbon chemistry analysis, and all use standard operating procedures for analyzing carbonate chemistry to identify the treatment conditions used in experiments.



Both deep sea and shallow reef-building corals have calcium carbonate skeletons.  As our oceans become more acidic, carbonate ions, which are an important part of calcium carbonate structures, such as these coral skeletons, become relatively less abundant. Decreases in seawater carbonate ion concentration can make building and maintaining calcium carbonate structures difficult for calcifying marine organisms such as coral.



Increased levels of carbon dioxide in our ocean can have a wide variety of impacts on fish, including altering behavior, otolith (a fish's ear bone) formation, and young fish's growth. Find out more about what scientists are learning about ocean acidification impacts on fish like rockfish, scup, summer flounder, and walleye pollock.


Shellfish, such as oyster, clams, crabs and scallop, provide food for marine life and for people, too. Shellfish make their shells or carapaces from calcium carbonate, which contains carbonate ion as a building block. The decreases in seawater carbonate ion concentration expected with ocean acidification can make building and maintaining calcium carbonate structures difficult for calcifying marine organisms like shellfish. This may impact their survival, growth, and physiology, and, thus, the food webs and economies that depend on them.


Plankton are tiny plants and animals that many marine organisms, ranging from salmon to whales, rely on for nutrition. Some plankton have calcium carbonate structures, which are built from carbonate ions. Carbonate ions become relatively less abundant as the oceans become more acidic. Decreases in seawater carbonate ions can make building and maintaining shells and other calcium carbonate structures difficult for calcifying marine organisms such as plankton. Changes to the survival, growth, and physiology of plankton can have impacts throughout the food web.


Genetic and phenotypic response of larval American lobster to ocean warming and acidification across New England’s steep thermal gradient

Dr. Richard Wahle & Dr. David Fields, University of Maine & Bigelow Laboratory for Ocean Sciences

Co-PI's Wahle (UMaine) and Fields (Bigelow Laboratory) join Co-investigator Greenwood (UPEI) in this US-Canadian collaboration. The proposed study is designed to fill knowledge gaps in our understanding of the response of lobster larvae to ocean warming and acidification across lobster subpopulations occupying New England’s steep north-south thermal gradient. The research involves a comprehensive assessment of the physiological and behavioral response of lobster larvae to climate model-projected end-century ocean temperature and acidification conditions. We will address the following two primary objectives over the 2-year duration of the proposed study:

(1)  To determine whether projected end-century warming and acidification impact lobster larval survival, development, respiration rate, behavior and gene expression; and

(2)  To determine whether larvae from southern subpopulations are more resistant than larvae from northern populations to elevated temperature and pCO2.

Wednesday, January 25, 2017
Categories: Projects

Synthesis and understanding of ocean acidification biological effects data by use of attribute-specific, individual-based models

Chris Chambers, NOAA Northeast Fisheries Science Center

This project uses data from experimental studies on the biological effects of ocean acidification (OA), largely funded by NOAA's Ocean Acidification Program (OAP), to construct realistic population‐process models of marine finfish populations.  The models are of an individual‐ based model (IBM) category that use detailed biological responses of individuals to OA.  This tool synthesizes OA data in two different ways.  First, it accumulates and connects data through mechanistic relationships between the environment and fish life‐history.  Second, it allows exploration of the population‐level consequences of CO2 effects (the source of OA) which explicitly include population effects carried over from the highly sensitive early life‐stages (ELS).   This information is fundamental to understanding the community and ecosystem effects of OA on living marine resources.  

Project efforts are directed at two different, complimentary levels.   At the more detailed, specific level, winter flounder – an economically important, well‐studied fish of Mid‐Atlantic to New England waters – will be used as a model subject.  Prior studies on winter flounder, augmented by OAP‐funded experimental work at NOAA/NEFSC, will provide estimates of CO2 effects on key life‐history and ecological parameters (e.g., fertilization, larval growth, development, and survival).  An IBM previously developed by the PIs will be updated and expanded to include OA effects on these parameters.  The winter flounder OA‐IBM will be exercised by evaluating the responses of the ELSs of this species under multiple scenarios:  high average levels of CO2 representing future oceans in shelf habitats; high and variable CO2 depicting future inshore, estuarine habitats; and covariances of CO2 with other environmental stressors (e.g., warmer waters, hypoxia).  At a general level and applicable to other species, the project will develop a web‐based tool that allows users to add details from other marine finfish of the NE USA and OA‐affected processes as relevant OA data on those species become available. 

Wednesday, November 16, 2016
Categories: Projects

Testing critical population level hypothesis regarding OA effects on early life history stages of marine fish for the N.E. U.S.

Chris Chambers, NOAA Northeast Fisheries Science Center

The primary goal of our OA projects (NEFSC Howard Laboratory) is to understand the impacts of increased CO2 and acidity of ocean and estuarine waters on important finfish species of our region. Our tactical objectives during FY12-14 were to develop, test, and then implement an experimental system that allows for the estimation of impacts of high CO2 and associated increased acidity of marine waters on the ELS of economically and ecologically important finfish species important to the NE USA. In FY15-17 we are building upon investments in research capacity and knowledge, and our experiments are addressing higher order questions that fold very well into one of the goals of the Interagency Working Group on OA – undertaking research to examine species-specific and multi-species physiological responses including behavioral and evolutionary adaptive capacities. We have four higher level objectives for our FY15-17 studies. 

First, we are testing our hypothesis that the resilience of the individuals in a population is inversely related to the variability of the CO2 in the habitat the population occupies (see also, Murray et al. 2014). This evaluation is being done by conducting comparative experiments among winter flounder from separate and distinct source populations whose resident habitats differ in characteristic levels and stability in CO2. Second, we are evaluating the role of parental exposure in the resilience / susceptibility of offspring to elevated CO2 (Sunday et al. 2014, Malvezzi et al. 2015). For these transgenerational studies, we are using three different forage species (original intent was to use Atlantic cod broodstock housed at the University of Maine but logistics and staffing decisions there precluded our use of those fish). Third, we are expanding our synthesis and meta-analysis of biological effects of CO2 on finfish. Lastly, we continue our education and outreach efforts on OA themes by mentoring students, conducting surveys, and providing tours of our OA experimental facilities.

Wednesday, November 16, 2016
Categories: Projects