Rather than conduct an aquatic roll call with nets to know which fish reside in a particular body of water, scientists can now use DNA fragments suspended in water to catalog invasive or native species.
“We’ve sharpened the environmental DNA (eDNA) tool, so that if a river or a lake has threatened, endangered or invasive species, we can ascertain genetic detail of the species there,” said senior author David Lodge, the Francis J. DiSalvo Director of the Atkinson Center for a Sustainable Future at Cornell, and professor of ecology and evolutionary biology. “Using eDNA, scientists can better design management options for eradicating invasive species, or saving and restoring endangered species.” Continue reading →
Most people assume that research equipment is expensive and complicated. But, it doesn’t need to be and the noise egg is a perfect example of this. It consists of a watertight container (as used by scuba divers) and the buzzer from a cellphone and does exactly what it says: it produces low frequency noise. This allows researchers to test the effect of noise on underwater life. It is a small, simple and cheap device that anyone can build.
Underwater noise is rapidly increasing due to, for example, boat traffic and offshore wind farms. This can lead to stress for animals and difficulties in communication. Just as people have a hard time communicating in a noisy pub, animals may struggle to get their messages across when background noise is high. A nice description of how animals use sound and how noise may affect this can be found at www.dosits.org
While there is some knowledge on the effect of noise on large aquatic animals, we still know very little about how fish and other small aquatic animals are affected. Such knowledge is vital for management of protected areas. It’s also important to know whether wind farms and boat traffic can affect reproduction in populations of underwater resources such as fish and mussels. The answers to these questions are likely to be species specific, so we’ll need data on a large number of species in different habitats. Continue reading →
Fish and invertebrates predominantly or exclusively detect particle motion.
A growing number of studies on the behaviour of aquatic animals are revealing the importance of underwater sound, yet these studies typically overlook the component of sound sensed by most species: particle motion. In response, researchers from the Universities of Bristol, Exeter and Leiden and CEFAS have developed a user-friendly introduction to particle motion, explaining how and when it ought to be measured, and provide open-access analytical tools to maximise its uptake. Continue reading →
Scientists at the University of Southampton have found a way to pry into the private lives of fish – by looking in their ears!
By studying ear stones in fish, which act as tiny data recorders, scientists can now reveal migration patterns and even provide insights into their sex life.
Managing fish stocks in a sustainable way is a major challenge facing scientists, conservationists, policy makers and fishermen. To get the best results, accurate information about the movements of fish in the wild is needed but gathering this information is extremely difficult. Continue reading →