Threats to marine life are approaching a tipping point, according to a UN Environment Programme (UNEP) report released Tuesday at the biodiversity summit in Nagoya, Japan.
The report, the Marine Biodiversity Assessment and Outlook: Global Synthesis predicts that by 2050 productivity will have decreased in nearly all areas and with it fish catches. Worldwide fisheries will be heavily dominated by smaller species lower down the food chain.
Meanwhile climate change, if unchecked, could see surface sea temperatures rise by 2100 with important implications for coral reefs and other temperature-sensitive marine organisms.
Other predicted changes include a continued and widespread increase in nitrogen levels. This is linked with discharges of wastewaters and agricultural run off from the land and, to an extent, emissions from vehicles and shipping.
Nitrogen can trigger algal blooms which in turn can poison fish and other marine creatures as well as contribute to the development of so called ‘dead zones’-areas of sea with low oxygen concentrations. These areas have increased since the mid-1960s and now cover an estimated 246,000 km2.
The report also flags concerns over the rise in marine invasive species, transported to regions from elsewhere often in ballast water of ships or attached to its hull. Furthermore, it highlights that the cumulative impacts of all of these factors will have serious consequences in the rise of extinctions of native marine species across all regions.
The continuing decline in marine biodiversity will compromise the resilience of marine and coastal ecosystems to the impacts of climate change, as well as their ability to mitigate the effects of climate change, says the report released alongside individual regional seas reports at the 10th Conference of the Parties to the Convention on Biological Diversity in Nagoya, Japan.
The full report is available at the link below.