David Johnson was standing in a salt marsh tidal creek north of Boston, Mass., when he scooped up a blue crab, Callinectes sapidus, 80 miles north of its native range. The northern migration of this commercially important species, Johnson says, could be yet another sign of climate change. Then a scientist at the Marine Biological Laboratory (MBL) Ecosystems Center, Johnson recently published his observations in the Journal of Crustacean Biology.
The historic northern limit of this species of crab (also called Atlantic blue or Chesapeake blue) is Cape Cod, Mass. They typically weren't found in the Gulf of Maine due to its cold Canadian waters.
From 2012 to 2014, however, scientists and resource managers observed blue crabs as far north as northern Maine and Nova Scotia, Canada. Johnson hypothesizes that warmer ocean temperatures in 2012 and 2013, which were 1.3°C higher than the previous decade's average, allowed the crabs to move north.
"Climate change is lowering the thermal barriers that kept species from moving toward the poles," he says. "Climate change presents a challenge not only for ecologists, but for fisheries managers as commercially important species shift their ranges in response to warming oceans."
Ephemeral populations of blue crabs have been documented previously in the Gulf of Maine. Johnson notes that in the 1950s blue crabs were observed in the gulf during a time of warmer waters. But once the waters returned to average temperatures, the crabs disappeared.
"It's too early to determine if the current blue crab population in the Gulf of Maine is permanent or ephemeral," Johnson says. "However, models predict an increasing warming of the world's oceans and recent observations of blue crabs may be a crystal ball into the future ecology of the Gulf of Maine."
Other researchers have documented the northern movement of other commercially important species in northeastern United States such as lobsters, hake and flounder. Johnson's work, however, is the first to document the movement of a commercially important species into the Gulf of Maine.
This is the second crustacean Johnson has documented as expanding into the Gulf of Maine. In 2014 he published his findings on the rapid expansion of the fiddler crab, Uca pugnax, into the gulf. "As the world's oceans continue to warm, we will continue to see climate-driven range expansions," he predicts.
Johnson, now an adjunct assistant scientist at the MBL, recently joined the Virginia Institute of Marine Science as an assistant professor.
Johnson DS (2015) The savory swimmer swims north: a northern range extension of the blue crab Callinectes sapidus? J. Crustacean Biology 35: 105-110.
The Marine Biological Laboratory (MBL) is dedicated to scientific discovery and improving the human condition through research and education in biology, biomedicine, and environmental science. Founded in Woods Hole, Massachusetts, in 1888, the MBL is a private, nonprofit institution and an affiliate of the University of Chicago.
Diana Kenney | EurekAlert!
127 at one blow...
18.01.2017 | Stiftung Zoologisches Forschungsmuseum Alexander Koenig, Leibniz-Institut für Biodiversität der Tiere
How gut bacteria can make us ill
18.01.2017 | Helmholtz-Zentrum für Infektionsforschung
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
18.01.2017 | Materials Sciences
18.01.2017 | Information Technology
18.01.2017 | Ecology, The Environment and Conservation