Phenology of marine species
Published (reviewed and quality assured)
Justification for indicator selection
Phenology is the study of annually recurring life-cycle events of species, such as the timing of migrations and flowering of plants. In the marine environment, phenology indicators include the timing of the spring phytoplankton bloom and the peak in abundance of other marine organisms. Change in phenology is one of the key indicators of the impacts of climate change on biological populations. Because marine species have different sensitivities to changes in temperature, these changes may lead to large shifts in the marine food web that can ultimately affect the food available to fish, birds or marine mammals. Differing responses have been seen across various levels of the food web.
Changes in the phenology of different plankton species are seen as a factor contributing to the decline in North Sea cod stocks, which was caused initially by over-fishing, and they have probably affected other fish populations (such as sand eels) that are an essential food source for seabirds.
In the North Sea, work on pelagic phenology has shown that plankton communities, including fish larvae, are very sensitive to regional climate warming. Responses to warming vary between trophic levels and functional groups, which may create a so-called ‘trophic mismatch’ between one species and their food source. The sexual maturation of decapoda larvae has been found to be particularly sensitive to water temperature and is therefore regarded as representative of phenological changes in the shelf-sea environments. Other taxa that also have their seasonal development closely triggered by temperature changes are also highly sensitive (e.g. echinoderm larvae, dinoflagellates, copepods).
- Sparks et al. 2006: Natural Heritage Trends of Scotland: phenological indicators of climate change. Sparks, T.H., Collinson, N., Crick, H., Croxton, P., Edwards, M., Huber, K., Jenkins, D., Johns, D., Last, F., Maberly, S., Marquiss, M., Pickup, J., Roy, D., Sims, D., Shaw, D., Turner, A., Watson, A., Woiwod, I. and Woodbridge, K. (2006). Natural Heritage Trends of Scotland: phenological indicators of climate change. Scottish Natural Heritage Commissioned Report No. 167 (ROAME No. F01NB01).
- Decapoda larvae abundance and phenology in the central North Sea
- Mean number of decapods per sample
- Month of peak abundance
Policy context and targets
In April 2009 the European Commission presented a White Paper on the framework for adaptation policies and measures to reduce the European Union's vulnerability to the impacts of climate change. The White Paper stresses the need to improve the knowledge base and to mainstream adaptation into existing and new EU policies. The European Commission will be publishing an EU Adaptation Strategy in 2013. A number of Member States have already taken action, and several have prepared national adaptation plans.
The European Commission and the European Environment Agency have developed the European Climate Adaptation Platform (Climate-ADAPT, http://climate-adapt.eea.europa.eu/) to share knowledge on observed and projected climate change and its impacts on environmental and social systems and on human health; on relevant research; on EU, national and subnational adaptation strategies and plans; and on adaptation case studies.
No targets have been specified.
Related policy documents
Climate-ADAPT: Mainstreaming adaptation in EU sector policies
Overview of EU sector policies in which mainstreaming of adaptation to climate change is ongoing or explored
Climate-ADAPT: National adaptation strategies
Overview of activities of EEA member countries in preparing, developing and implementing adaptation strategies
DG Climate Action: What is the EU doing about climate change?
Activities of the EU regarding climate change (both mitigation and adaptation)
White paper - Adapting to climate change: towards a European framework for action
EU framework for adaptation to climate change, leading to a comprehensive EU adaptation strategy by 2013
Key policy question
How is climate change affecting the seasonal cycle of marine organisms in European seas?
Methodology for indicator calculation
Data from the Sir Alister Hardy Foundation for Ocean Science (SAHFOS) on Decapoda larvae abundance in the central North Sea 1958–2009 is used for the indicator. The Continuous Plankton Recorder (CPR) survey is the longest running, large-scale marine biological survey in the world. The CPR is a near-surface (10 m) plankton sampler voluntarily towed each month behind merchant ships on their normal routes of passage. Methods of analysis for, 400 phyto and zooplankton taxa have remained almost unchanged since 1958.
Methodology for gap filling
- Warner and Hays (1994): Sampling by the continuous plankton recorder survey Progress in Oceanography , Volume 34, Issues 2–3 , 1994, Pages 237–256
EEA data references
- No datasets have been specified here.
External data references
Data sources in latest figures
Data sets uncertainty
In general, changes related to the physical and chemical marine environment are better documented than biological changes because links between cause and effect are better understood and often time series of observations are longer. The longest available records of plankton are from the Continuous Plankton Recorder (CPR) are some 60 years long. It is a sampler that is towed behind many different merchant vessels, along fixed shipping routes. Sampling was started in the North Sea in the 1950s and today a network covering the entire north Atlantic has been established. No other plankton time series of equivalent length and geographical coverage exist for the European regional seas, although many new initiatives investigating species distributions and their changes in Europe’s seas are now emerging.
Further information on uncertainties is provided in Section 1.7 of the EEA report on Climate change, impacts, and vulnerability in Europe 2012 (http://www.eea.europa.eu/publications/climate-impacts-and-vulnerability-2012/)
No uncertainty has been specified
Short term work
Work specified here requires to be completed within 1 year from now.
Long term work
Work specified here will require more than 1 year (from now) to be completed.
Responsibility and ownership
EEA Contact InfoTrine Christiansen
Typology: Descriptive indicator (Type A – What is happening to the environment and to humans?)