Fish Carbon: Exploring Marine Vertebrate Carbon Services

MARINE VERTEBRATE CARBON SERVICES

Marine vertebrate carbon services, termed ‘Fish Carbon’, consist of eight different biological carbon cycling mechanisms (Figure 2). Traditionally thought to contribute minimally to the oceanic carbon cycle, Fish Carbon pathways are not included in current carbon cycle models, aside from an implicit connection with plankton (Steele and Henderson 1992, Ohman et al. 2002).

The Fish Carbon mechanisms described in this report demonstrate that, in healthy marine ecosystems, marine vertebrates facilitate uptake of atmospheric carbon into the ocean and transport carbon from the ocean surface to deep waters and sediment, thus providing a vital link in the process of long term carbon sequestration. Fish Carbon additionally provides a natural buffer against ocean acidification through the Bony Fish Carbonate mechanism. As such, Fish Carbon potentially lends itself to the global climate challenge in mitigation of both atmospheric and oceanic impacts of climate change.

future scientific endeavour; understanding the scale of Fish Carbon relative to the carbon flux associated with plankton and microbes, and interactions between these, is a key next step. However, these Fish Carbon mechanisms also permit innovative policy and management action based on the best available scientific information and the precautionary principle; an approach called for in the management of marine resources and in climate change policy (FAO 1995, United Nations 1995, Kunreuther et al. 2013, FAO 2014). The eight Fish Carbon mechanisms, and the implications of broader marine policy on their success, are described in the following sections.

The ecosystem-based mechanisms presented here, largely built on recent scientific research, provide a framework for

Figure 2. A conceptual diagram of marine vertebrate carbon services (not to scale) (building on Barber 2007, Roman and McCarthy 2010, Wilmers et al. 2012, Heithaus et al. 2014). See following text for further explanation of the 8 different services.

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