Basin-Scale Coherence in Phenology of Shrimps and Phytoplankton in the North Atlantic Ocean

Abstract

Climate change could lead to mismatches between the reproductive cycles of marine organisms and their planktonic food. We tested this hypothesis by comparing shrimp (Pandalus borealis) egg hatching times and satellite-derived phytoplankton bloom dynamics throughout the North Atlantic. At large spatial and long temporal (10 years or longer) scales, hatching was correlated with the timing of the spring phytoplankton bloom. Annual egg development and hatching times were determined locally by bottom water temperature. We conclude that different populations of P. borealis have adapted to local temperatures and bloom timing, matching egg hatching to food availability under average conditions. This strategy is vulnerable to interannual oceanographic variability and long-term climatic changes.

Seasonality of North Atlantic phytoplankton from space: impact of environmental forcing on a changing phenology (1998–2012)

“…At the same time, diverging trends in the timing of different peaks suggested an increase in seasonal stratification, the main consequence of increased surface warming (Sarmiento et al, 1998). Changes in bloom timing and magnitude might have also impacted several fisheries around the Atlantic (Platt et al, 2003;Koeller et al, 2009).…”

“…Studies on marine phenology have focused on the main peak of phytoplankton growth in temperate and polar regions, i.e. the spring phytoplankton bloom, and have highlighted the great variability in this event and a trend towards an early occurrence of these blooms in northern latitudes in recent years Platt & Sathyendranath, 2008;Henson et al, 2009;Kahru et al, 2011;Zhai et al, 2011), as well as the importance of trophic mismatches (Beaugrand et al, 2003;Platt et al, 2003;Koeller et al, 2009;Kristiansen et al, 2011). Secondary pulses during the fall in temperate latitudes and autumn/winter blooms in subtropical and tropical regions have received in general less attention (but see Ueyama & Monger, 2005;Martinez et al, 2011;Cole et al, 2012;Sapiano et al, 2012).…”

Impact of decadal reversals of the north Ionian circulation on phytoplankton phenology

“…Phytoplankton blooms are crucial events in the ocean as they contribute significantly to primary production and carbon export, (Buesseler, 1998) but also sustain the trophic food web. Thus, any changes in phytoplankton phenology may have large consequences on higher trophic levels (Edwards and Richardson, 2004;Koeller et al, 2009). Although the characterization of phytoplankton phenology in the open ocean has long been hindered by data scarcity, in the past few years, satellite ocean color observations have offered a general view of the phenology of the surface phytoplank-ton biomass at global scale (Platt et al, 2010).…”

Cold truths at the top of the world

“…Today, about 40% of Greenland's workers are employed by According to Helle Siegstad, director of fish and shellfish at the Greenland Institute of Natural Resources in Nuuk, the culprit could be Atlantic cod (Gadus morhua), a predator that could benefit from warming near Greenland and has started to reappear after being overfished. Another factor behind the shrimp's decline might be that climate change has caused a mismatch between their hatching time and the blooms of phytoplankton that they eat 4 . But higher water temperatures have also lured new species north, such as Atlantic mackerel, Atlantic herring and even some bluefin tuna 5 , says Brian MacKenzie, a marine ecologist at the Technical University of Denmark in Kongens Lyngby.…”