Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Envisat fishes up facts behind Chilean giant squid invasion

23.03.2004


Masses of large ocean-going squid have inundated the shores of Southern Chile, alarming local fishermen who fear these carnivorous invaders could threaten fish stocks. Envisat has helped account for their otherwise mysterious arrival.


This beached jumbo flyung squid is a mysterious deep sea visitor to the Chilean coastline, one of hundreds making a surprise appearance during February 2004, alarming local fishermen. But Envisat AATSR data has shed light on the mystery.

Credits: Mariscope Chilena



These jumbo flying squid – Dosidicus gigas is their Latin name – are some of the largest known squids on the planet: the ones here measure between 70 to 150 centimetres in length, although specimens have been known to reach more than three metres. Making their home in the open ocean, they rise to the surface at night to aggressively feed on small fish using barbed suckers.

In the final days of February more than 200 of the squid were washed up on the beaches around Ancud, on the northern coast of the island of Chiloé in southern Chile. Further incursions have since taken place towards Calbuco, on the inner side of the Chacao channel and towards the southern part of the island along the coast, up to Castro in the middle of the big island of ’Los Lagos’ region of the country. Strandings have also been reported in more northerly areas such as Chile’s VIII region.


Wondering why these deepwater animals unexpectedly made it to coastal waters is a matter of more than just scientific interest. Thousands of Chileans earn their livelihood from fishing in this part of the country, and these voracious cephalopods are known to prey on commercial fish including hake, sardines and anchovies. The squid themselves are a delicacy in some parts of the world but there is no local tradition of catching or consuming them.

But an explanation for the incursions was available – from 800 km away in space. Envisat’s Advanced Along Track Scanning Radiometer (AATSR) instrument works like a space-based thermometer, taking the temperature of land and sea as it orbits the Earth. It can measure sea surface temperature (SST) to an accuracy of 0.3 degrees centigrade at a spatial resolution of one square km.

A Chilean team is currently working with AATSR SST results in combination with ocean colour data from another Envisat instrument, the Medium Resolution Imaging Spectrometer (MERIS). Chile’s national fish farming association Salmon Chile has co-founded a pilot scheme with oceanography firm Mariscope Chilena, investigating the feasibility of a satellite-based early warning system for harmful phytoplankton blooms – explosive growths of sometimes toxic marine algae.

"The AATSR results show the appearance of the squid was connected with changes in the water mass conditions off the coast of Southern Chile in recent weeks," says Dr Cristina Rodríguez-Benito of Mariscope Chilena.

This part of the Chilean coast, like most western continental coasts, is subject to upwellings – cold, nutrient-rich waters rise from the oceans depths as prevailing winds blow warmer surface waters away. The phenomenon supports rich fisheries. But the AATSR data reveal that a coastal upwelling that typically influencing the waters between Chiloé and the mainland was not seen in the last week of February.

"This caused an influx of warmer water, between 0.5 and 1.5 degrees, and also squid, which are attracted to steep temperature and salinity gradients in the sea where they find their food," adds Rodríguez-Benito. "The squid ended up in a lens of cold water between warmer masses, and this carried them into the inner Gulf of Ancud area.

"The resulting decrease in water temperature can also have a direct effect on aquaculture, because the metabolic systems of fish species are very sensitive to such changes. Envisat’s AATSR data registered a decrease of up to 3ºC.

"Even more important than temperature is the indication of the entrance of a water mass poor in oxygen that could be the reason for the losses already registered in some aquaculture sites.


"We are interested in such events as part of our main project because temperature gradients are often where new phytoplankton blooms occur. But the possibility of being able to predict these phenomena would be very useful also to the fishing industry."

The team plans to present their experiences of using Envisat data in this way to a conference this month of the Chilean Civil Protection Organisation.

Frédéric Le Gall | ESA
Further information:
http://www.esa.int/esaSA/SEMVNJYV1SD_earth_0.html

More articles from Ecology, The Environment and Conservation:

nachricht Upcycling 'fast fashion' to reduce waste and pollution
03.04.2017 | American Chemical Society

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>