Wild salmon, in their migrations across the oceans, are one of the natural world’s most sensitive indicators of the biological and chemical effects of climate change, according to Dr. Ken Whelan, whose talk “Salmon – The Climate Change Forecasters” was delivered this evening to a capacity audience at the Royal Irish Academy in Dublin (8th October). The talk was part of the Academy’s “Threats to the Environment” lecture series.
According to Dr. Whelan, recent research has shown quite clearly that aquatic systems are changing and changing fast. Water is getting warmer, storms are getting stronger and the availability of food resources in and from the ocean is under threat. Oceans and atmosphere are intimately and inextricably linked. Changes in the oceans are “forcing” unprecedented shifts in climate patterns.
“Similar patterns are apparent in freshwater,” said Dr. Whelan. “We have recently witnessed a series of unprecedented rainfall deluges which have caused massive landslides and the dislocation of tonnes of mud, silt and peat. Such climate perturbations are also causing major biological modifications including the appearance of new species off the coast and the spread of non native species around the coast and in freshwater.”
The research carried out by Dr Whelan and his colleagues has shown that the Atlantic salmon is an ideal bio-monitor to track and trace climate change from remote mountain streams to distant zones in the Artic seas. The salmon, which is equally at home in both fresh and saltwater, traverses large areas of the planet in a relatively short space of time but is endowed with an uncanny ability to find its way home. Throughout its odyssey the salmon collects and stores a wide range of physical, chemical and biological information (www.salmonatsea.com).
“Although the science is complex the take home message is clear,” said Dr. Whelan. “Adaptation to climate change is in our hands. Combating climate change requires a clear and unambiguous focus on: monitoring change, responding to change, conserving populations of animals and plants and relieving man made stresses on the environment.”
Dr Ken Whelan is Director of the Marine Institute’s Aquaculture and Catchment Management Services Team, based at Newport, Co. Mayo (www.marine.ie).
ENDS
For further information, please contact:
Dr John Joyce – Communications Manager, Marine Institute
Phone: + 353 87 2250871
Notes to Editor
Salmon Survival and Our Changing Oceans
Climate induced changes in the ocean ecosystems are a cause for considerable concern. Some are warming, some are cooling and melting ice is diluting the upper layers of the northern and southern oceans. There is increasing evidence that currents are changing. First to encounter these changes are the long-distance migrants that traverse these troubled zones – the sharks, the tunas and the salmon.
Wild salmon numbers declined dramatically in the late 20th century. Over the last thirty years much money and effort has been spent in research to understand the life cycle of the salmon, its interaction with its environment, and the threats that it faces. We now have a much clearer understanding of the salmon’s life in rivers and inshore waters. The knowledge has led to a cleaner environment, fewer obstructions, improved habitat and reduced threat from commercial exploitation.
However, salmon numbers have continued to decrease. A key reason is that fewer salmon are returning from the ocean. An increasing proportion of salmon are dying at sea. In some southern rivers on both sides of the North Atlantic wild salmon face extinction. No one fully understands why. There are many theories but as yet no sound research base on which rational action can be taken.
Research in the open ocean is very expensive, requiring international collaboration. Until now it could not promise clear and comprehensive results but recent advances in DNA analysis make it possible to identify from a single fish scale the river population to which a salmon belongs – a natural genetic ‘identity tag’. Scientists are compiling a genetic river atlas for the North Atlantic salmon population and a carefully-targeted series of ocean surveys is underway. Innovative new trawl-gear that records salmon numbers passing through the net and enables live capture is being developed and tested.
SALSEA, the international Salmon at Sea research programme being developed under the auspices of the North Atlantic Salmon Conservation Organisation (NASCO) and the International Atlantic Salmon Research Board (IASRB). The programme is designed to use new and emerging technologies in the fastest and most comprehensive way to gain knowledge on which action can be taken. The core of the programme has been be a series of voyages during 2008-2009 that have mapped salmon distribution and movement throughout the North Atlantic and monitored the health of the fish and the chemical and physical characteristics of their environment. SALSEA Merge and SALSEA North America commenced in May 2008.
The knowledge acquired will not only help the North Atlantic salmon. Each wild salmon traverses a spectrum of aquatic environments from fresh water to ocean brine, physiologically changing in response to each environment and sensitive to the quality of its surroundings. The research will therefore provide a significant advance in understanding changes in the ocean environment, their effects on the creatures that live there and, ultimately, their effects on our own lives.