30 December 2009
24 December 2009
Even small MPAs may be good for killer whales
"Protecting even small patches of water can provide conservation benefits, as long as we choose the spots wisely," said Erin Ashe, author of a recent publication on the behaviour of killer whales (in British Columbia and Washington State) and marine protected areas.
Ashe and colleagues suggested that even small protected areas, identified through feeding behaviour, can benefit highly mobile marine predators such as killer whales. They indicated this after mapping locations where killer whales were observed feeding, socializing and resting, and identifying a small area in which whales were almost three times as likely to be feeding as they were in the rest of the region.
Protecting this little area could be crucial for two reasons. First, Chinook salmon, the favourite prey of this cetacean population, has declined in the region. Second killer whales are more disturbed by boat traffic when engaged in feeding activities than when they are travelling. Researchers think that management strategies to protect feeding hotspots should give greater conservation benefits than a generic habitat protection.
SB
---
Ashe E., Noren D.P., Williams R. 2009. Animal behaviour and protected areas: habitat conservation for an endangered killer whale population. Animal Conservation. DOI:10.1111/j.1469-1795.2009.00321.x
For more information:
http://www.sciencedaily.com/releases/2009/12/091216203438.htm
Pubblicato da Silvia Bonizzoni a 09:25 0 commenti
22 December 2009
Lode al Capodoglio
Arturo Bolognari, 1957:
“Formuliamo infine l’augurio che il Capodoglio, anziché subire la sorte di dover scomparire per la caccia spietata che l’uomo gli va conducendo da secoli, possa continuare a solcare, siccome il suo istinto esige, tutti i mari del globo, per testimoniare così, con la sua immensa mole, alla quale si accoppiano forza agilità e bellezza, un’opera altamente significativa della Natura. E forse sarebbe un rendergli giustizia non considerarlo più come un mostro dei mari, ma come un essere che ha il suo pieno diritto di vivere indisturbato sulla Terra.”
Da: Bolognari A. 1957. Sulla biologia del capodoglio. Atti della Società Peloritana di Scienze Fisiche, Matematiche e Naturali 3(2):143-156.
Pubblicato da Silvia Bonizzoni a 08:25 0 commenti
21 December 2009
Sperm whales: final destination
Between December 10th and 11th seven sperm whales stranded and died - on the northern coast of the Gargano Peninsula (Apulia, Italy). They were all sub-adult males.
After several meetings the experts decided what to do with the dead animals, but in the meantime the carcasses are still on the beach. Each animal will be cut into parts. Carcasses will then be buried and covered with ground and lime. The decomposition process is expected to complete in one year. At the end of this period the skeletons will be recovered, treated and displayed in museums.
Numerous hypotheses were made regarding the causes of the stranding, from plastic ingestion to seismic surveys, seaquakes, etc. But the fact is: the reasons are still unknown and the experts are working hard to find out.
Silvia Bonizzoni
Pubblicato da Silvia Bonizzoni a 09:16 3 commenti
19 December 2009
Mediterranean Sea: an example of the oceans' destiny?
A recent review describes how the Mediterranean Sea could offer an idea of the disastrous future of the oceans.
This review of more than 100 studies on the Mediterranean’s changing ecological dynamics, describes the convergence of climate change and human impacts in waters that had been stable since the time of Aristotle.
Rising temperatures, disrupted deep-water hydrology, overfishing, shrinked food-webs, mass die-offs, diseases and pollution are some of the threats that are affecting the Mediterranean Sea. Other sea areas on Earth may not escape from this sad degradation destiny. The future doesn’t look so nice...
SB
---
Lejeusne C., Chevaldonné P., Pergent-Martini C., Boudouresque C.F., Pérez T. 2009. Climate change effects on a miniature ocean: the highly diverse, highly impacted Mediterranean Sea. Trends in Ecology and Evolution. doi:10.1016/j.tree.2009.10.009
Abstract:
Little doubt is left that climate change is underway, strongly affecting the Earth's biodiversity. Some of the greatest challenges ahead concern the marine realm, but it is unclear to what extent changes will affect marine ecosystems. The Mediterranean Sea could give us some of the answers. Data recovered from its shores and depths have shown that sea temperatures are steadily increasing, extreme climatic events and related disease outbreaks are becoming more frequent, faunas are shifting, and invasive species are spreading. This miniature ocean can serve as a giant mesocosm of the world's oceans, with various sources of disturbances interacting synergistically and therefore providing an insight into a major unknown: how resilient are marine ecosystems, and how will their current functioning be modified?
---
For more information:
http://www.wired.com/wiredscience/2009/12/mediterranean-degradation/
Pubblicato da Silvia Bonizzoni a 11:49 0 commenti
18 December 2009
700 Facebook fans!
Not yet a Tethys fan? Visit our Facebook page and join us!
Already a Tethys fan? Thank you :-)
Tethys's facebook page
Pubblicato da Silvia Bonizzoni a 08:43 0 commenti
14 December 2009
Mass stranding of sperm whales in southern Italy
An updated photo album as well as a low-resolution video of two agonising sperm whales can be viewed at:
http://www.istitutotethys.org/gargano/
Pubblicato da Giovanni Bearzi a 12:30 0 commenti
12 December 2009
Mass stranding of sperm whales
Between Thursday 10 and Friday 11 December a pod of seven sperm whales stranded on the coast of the Gargano Peninsula (Italy), in the Adriatic Sea.
The animals, including several males of 10+ m, are scattered along a stretch of about six km of beach. Five have already died.
Scientists from the Centro Studi Cetacei, the Natural History Museum of Milan, and the Italian universities of Bari, Padua, Pavia and Siena, among others, are on site and coordinate operations and scientific analyses.
Giovanni Bearzi and Silvia Bonizzoni, who live in Apulia not too far from the stranding area, went to have a look.
See what they found:
http://www.istitutotethys.org/gargano/
Pubblicato da Silvia Bonizzoni a 17:19 0 commenti
Mega-flood filled the Mediterranean in less than two years
Around 5.6 million years ago tectonic movements and a drop in sea level cut the Mediterranean out of the worlds' oceans. For 300 million years our sea dried up almost everywhere, in what is called the Messinian salinity crisis.
The water then returned: what started like a trickle, later became an event of biblical proportions which filled the Mediterranean in under two years. At peak times, the sea level rose by up to ten meters a day - the largest known flood in Earth's history.
Daniel Garcia-Castellanos of the Jaume Almera Institute of Earth Sciences in Barcelona, Spain, and colleagues, who published their work on Nature, estimate the peak flow to have been around 1000 times higher than the present Amazon river at its highest rate.
Eleonora de Sabata
---
For more information:
- Catastrophic flood of the Mediterranean after the Messinian salinity crisis
- Castellano's page
Pubblicato da Giovanni Bearzi a 05:51 0 commenti
11 December 2009
Lower frequency in blue whale songs
Blue whales are not singing as they were used to do. Their songs’ tonal frequency is decreasing every year by a few fractions of an hertz.
Global warming, noise pollution, changing population dynamics and new mating strategies are the possible reasons, but none of these hypotheses provide a full explanation and researchers have not yet found the real clue.
---
McDonald M., Hildebrand J., Mesnick S. 2009. Worldwide decline in tonal frequencies of blue whale songs. Endangered Species Research 9:13-21.
Abstract:
Blue whale Balaenoptera musculus songs can be divided into at least 10 types worldwide, each type retaining the same units and similar phrasing over decades, unlike humpback whale song which changes substantially from year to year. Historical acoustic recordings dating back as far as the 1960s were examined, measuring the tonal frequencies of 1000s of blue whale songs. Within a given year, individuals match the song frequency (related to ‘pitch’ in musical nomenclature) to within less than 3%. The best documented song type, that observed offshore of California, USA, now is sung at a frequency 31% lower than it was in the 1960s. Data available for 7 of the world’s 10 known song types show they are all shifting downward in frequency, though at different rates. Any behavioral, ecological, oceanographic or anthropogenic change hypothesis seeking to explain the observed shifts should account for the worldwide occurrence of a nearly linear downward shift in the tonal frequencies of blue whale song. Hypotheses examined consider sexual selection, increasing ocean noise, increasing whale body size post whaling, global warming, interference from other animal sounds and post whaling increases in abundance. None of the commonly suggested hypotheses were found to provide a full explanation; however, increasing population size post whaling provides an intriguing and testable hypothesis that recovery is altering the sexually selected tradeoff for singing males between song amplitude (the ability to be heard at a greater distance) and song frequency (the ability to produce songs of lower pitch).
Pubblicato da Silvia Bonizzoni a 05:12 0 commenti
10 December 2009
Tethys Seaway
Click on figure to enlarge.
From:
STEEMAN, M.E., M.B. HEBSGAARD, R.E. FORDYCE, S.Y.W. HO, D.L. RABOSKY, R. NIELSEN, C. RAHBEK, H. GLENNER, M.V. SORENSEN, E. WILLERSLEV. 2009. Radiation of extant cetaceans driven by restructuring of the oceans. Systematic Biology 58(6):573-585.
Pubblicato da Giovanni Bearzi a 09:38 0 commenti
09 December 2009
Oceans for Pathi
Oceans for Pathi is a new nature film based on revolutionary techniques that allowed enjoying the secrets of the oceans as never before.
Thanks to remote-controlled mini helicopters and hydrodynamic cameras, the film reached the goal of ‘catching’ the ocean's most intimate events. For this purpose the crew worked in 50 different locations and filmed 80 marine species, from crabs to whales.
It took four years, 500 hours of footage and £45 million to be produced but the result must be amazing!
The film will be out for general release by the end of January 2010.
SB
----
Photo by Barcroft Media: an example of how some whale footage was obtained.
More information in the DailyMail article
Pubblicato da Silvia Bonizzoni a 05:42 0 commenti
08 December 2009
Video of the Month: December 2009
Disappearing Dolphins
by Chris and Genevieve Johnson / earthOCEAN
NEW - Short version (7 min 20 sec)
2009
Common dolphins were once abundant throughout the Mediterranean Sea. Today, they are declining rapidly, surviving only in portions of their former range. In western Greece, the sea around the island of Kalamos is their last stronghold, or at least it used to be. So why are the dolphins disappearing?
We interview Giovanni Bearzi, the President of the Tethys Research Institute in Italy, and a Pew Fellow in Marine Conservation. Giovanni has been studying coastal dolphins in the Eastern Mediterranean Sea for two decades. What began as a study on the ecology and behavior of common dolphins around Kalamos, became a systematic record of their demise.
See the original version (18 minutes)
---
View complete list of Tethys Videos of the Month
View complete list of Tethys Books of the Month
Pubblicato da Giovanni Bearzi a 08:29 0 commenti
07 December 2009
Book of the Month: December 2009
The Origin of Species
by Charles Darwin
1859
Penguin Classics, London
Charles Darwin's On the Origin of Species, published on 24 November 1859, is a seminal work of scientific literature, considered to be the foundation of evolutionary biology. Its full title was On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. For the sixth edition of 1872, the short title was changed to The Origin of Species. Darwin's book introduced the theory that populations evolve over the course of generations through a process of natural selection. It presented a body of evidence that the diversity of life arose by common descent through a branching pattern of evolution. Darwin included evidence that he had gathered on the Beagle expedition in the 1830s and his subsequent findings from research, correspondence, and experimentation. The book was written for non-specialist readers and attracted widespread interest upon its publication. Within two decades there was scientific agreement that evolution, with a branching pattern of common descent, had occurred, but scientists were slow to give natural selection the significance that Darwin thought appropriate. During the "eclipse of Darwinism" from the 1880s to the 1930s, various other mechanisms of evolution were given more credit. With the development of the modern evolutionary synthesis in the 1930s and 1940s, Darwin's concept of evolutionary adaptation through natural selection became central to modern evolutionary theory, now the unifying concept of the life sciences. (Adapted from Wikipedia)
---
View complete list of Tethys Books of the Month
View complete list of Tethys Videos of the Month
Pubblicato da Giovanni Bearzi a 08:14 0 commenti
06 December 2009
Book of the Month: November 2009
Guida dei Mammiferi Marini del Mediterraneo
by Giuseppe Notarbartolo di Sciara and Massimo Demma
2004 (First edition: 1994)
Franco Muzzio Editore, Padova
---
View complete list of Tethys Books of the Month
View complete list of Tethys Videos of the Month
Pubblicato da Giovanni Bearzi a 08:08 0 commenti
03 December 2009
Tethys workshop
On December 2nd, Tethys organised an internal workshop that had a considerable attendance (25 collaborators, including juniors and seniors).
On this occasion, the participants presented and discussed the research and conservation activities conducted since 1986, the ongoing projects in the Pelagos Sanctuary and in Greece, and the future goals and "vision" of the Institute.
Nine presentations were scheduled:
- Synthesis of the work done by Tethys, 1986-2009 (Giovanni Bearzi)
- An overview of Tethys field courses, 1990-2009 (Stefano Agazzi)
- The dolphins of the Amvrakikos Gulf, Greece (Joan Gonzalvo)
- The new research project in the Gulf of Corinth, Greece (Silvia Bonizzoni)
- Cetacean Sanctuary Research: 20 years in the Pelagos Sanctuary (Sabina Airoldi and Simone Panigada)
- The "Habitat" project (Arianna Azzellino)
- Fin whale feeding areas in the western Ligurian Sea (Maddalena Jahoda)
- Aerial and naval surveys in the Pelagos Sanctuary (Simone Panigada)
- The Tethys project on cetacean collisions with ships (Elisa Remonato)
Silvia Bonizzoni
---
Photo: Some of the participants in the Tethys workshop held at the Milan Civic Aquarium on December 2nd, 2009 (click on photo to enlarge)
Pubblicato da Silvia Bonizzoni a 14:17 0 commenti
01 December 2009
EU funded tens of millions to fish for depleted tuna
The European Union has given out €34.5 million, between 2000 and 2008, to subsidise the Mediterranean tuna fishing fleets despite warnings from scientists that overfishing is pushing the species close to extinction.
Joe Borg, the European Fishery Commissioner, revealed that €23 million was given to fund the construction of new boats, including ultra-modern purse seiners that are able to land 100 tonnes in one haul. A further €10.5 million was given to modernise existing vessels, increasing their ability to track down and catch the tuna. Only €1 million was used to decommission vessels, but mainly for small-scale, local boats.
Spain received more than half of the subsidy, with French and Italian fleets the next biggest beneficiaries. Cyprus, Malta and Greece were also given money.
Scientists from ICCAT (International Council for the Conservation of Atlantic Tuna) believe that the bluefin tuna stock was below 15 per cent of its pre-exploitation levels.
Read full article on the Times
Eleonora de Sabata
Pubblicato da Giovanni Bearzi a 18:12 0 commenti