A recent study on elephants in zoos found out something that many of us probably already suspected... these captive animals are at risk of depression and unhappy if kept alone or in small groups.
The important point made by the author Paul Rees is that life in small groups is unnatural for herd animals.
In their ‘normal’ life elephants are used to having many contacts with members of their own species, and this is crucial for the animals to develop normal behaviour patterns and friendships.
If they are forced to stay with just a few other individuals they cannot learn important socials skills such as finding a mate or greeting rituals, and many of them begin showing abnormal behaviour that suggests depression.
This study represents another reason to re-consider the ethical implications of keeping animals in captivity for human amusement.
Photo from: http://animalphotos.info
For more information:
Rees P.A. 2009. The sizes of elephant groups in zoos: implications for elephant welfare. Journal of Applied Animal Welfare Science 12 (1):44-60. (Abstract only)
26 February 2009
25 February 2009
Abbiamo finalmente concluso il survey aereo invernale. Il tempo non è stato troppo clemente, ma siamo riusciti a completare i transetti. L'area di studio è stata coperta come previsto in condizioni quasi sempre ottimali, a parte qualche transetto nella costa occidentale, a sud di Tolone dove a causa di una zona militare sempre attiva non siamo riusciti a volare.
Il bilancio è positivo, 117 avvistamenti di stenella striata, 4 di tursiope, 1 di zifio e 1 di balenottera comune (vista finalmente il 20 febbraio). Salta all'occhio la totale mancanza di balenottere e delle altre specie presenti nei mesi estivi.
Pubblicato da Giovanni Bearzi a 07:42
24 February 2009
If you don't bother to read scientific papers about the present condition of our oceans, you can simply watch the impressive lecture given by Jeremy Jackson at UCLA (University of California, Los Angeles).
"Brave new ocean"
Jeremy Jackson is a marine ecologist based at Scripps Institute of Oceanography. In 2003, Jackson and Daniel Pauly co-founded ‘The Shifting Baselines Ocean Media Project’ to help promote a wider understanding and use of the term in discussions of general conservation. Shifting Baselines is a sort of partnership between ocean conservation and Hollywood to help bring attention to the severity of ocean decline, to point out that the changes people saw in their 20th-century lifetimes were just small snapshots in a larger picture of environmental decline that has been accelerating for 200 years.
For more information:
"Every ecosystem I studied is unrecognizably different from when I started. I have a son who is 30, and I used to take him snorkelling on the reefs in Jamaica to show him all the beautiful corals there. I have a daughter who is 17... I can't show her anything but heaps of seaweed."
-- Jeremy Jackson
Pubblicato da Silvia Bonizzoni a 07:41
21 February 2009
NOAA (National Oceanic and Atmospheric Administration) has launched the ‘National Marine Sanctuaries Media Library’, a new online multimedia library with public access.
The online library is a comprehensive database containing a collection of thousands high-quality ocean-related photos and videos taken by NOAA scientists, educators, divers and archaeologists.
Thank to an easy search system it is possible to find materials on 13 themes: birds, culture/people, fish, invertebrates, marine mammals, marine reptiles, maritime heritage, media roll, plants, scenic, science/research, ships/vessel/facilities, treats/pressures.
Have a look!
For more information:
Pubblicato da Silvia Bonizzoni a 06:57
20 February 2009
On February 17th, Tethys researcher Joan Gonzalvo attended a meeting at the city hall of Vonitsa, Greece, organized by the Management Body of the Amvrakikos Wetlands.
This body was established after the creation of the Amvrakikos Gulf National Park on March 21st, 2008. The meeting was attended by local authorities, a research team from the University of Patras, the Hellenic Centre for Marine Research (HCMR), the Development Agency for South Epirus and Amvrakikos (ETANAM), and local fishermen representatives.
The local fishermen proposed Joan’s participation in the event as an independent observer. A series of presentations by the participants reviewed the dramatic problems faced by the Gulf, namely increasing eutrophication and pollution. Especially alarming was the presentation by Prof. Kostas Koutsikopoulos (University of Patras) who studied the oxygen concentration on the sea floor and deep waters of the Gulf. His results show that anoxic conditions are found in waters deeper than 23 m, while twenty years ago such conditions were observed in waters 40 m deep and below. According to professor Koutsikopoulos, today approximately 70% of the Gulf is, in his own words, a dead zone.
Local fishermen did not seem surprised at all about the evidence shown. They have been claiming that the situation of the Amvrakikos Gulf is critical for several years as indicates by steadily decreasing fish captures.
Participants in the meeting acknowledged the uniqueness of the Gulf and its increasing vulnerability to human impact. The authorities promised to react and try to address the problem.
The good news are that the University of Patras, HCMR and ETANAM have manifested their interest in collaborating with Tethys. Such synergy would be important to take advantage of the intensive work done by Tethys since 2002 to document the abundance, movements and trends of bottlenose dolphins that reside year-round in the troubled waters of the Amvrakikos Gulf .
For more information:
Bearzi G., Agazzi S., Bonizzoni S., Costa M., Azzellino A. 2008. Dolphins in a bottle: abundance, residency patterns and conservation of bottlenose dolphins Tursiops truncatus in the semi-closed eutrophic Amvrakikos Gulf, Greece. Aquatic Conservation: Marine and Freshwater Ecosystems 18(2):130-146.
Pubblicato da Giovanni Bearzi a 06:01
19 February 2009
La scorsa settimana è stata avvistata una balena nei pressi di Trieste, Koper e Izola (Slovenia), ma non era stato ancora possibile identificarne la specie.
Il 16 febbraio, la balena è stata riavvistata lungo la costa slovena e i ricercatori di Morigenos, precipitatisi in mare, hanno potuto constatare che si trattava di un esemplare di megattera (Megaptera novaeangliae) di circa 10-12 metri. Il cetaceo è apparso in buone condizioni e ha passato l’intera giornata nella baia di Pirano.
Questo avvistamento è di particolare importanza, in quanto le megattere visitano raramente il Mediterraneo; si consideri infatti che questa specie, dal 1986 al 2006 e in tutto il bacino, è stata avvistata solo in 12 occasioni. L’ultimo, nonché unico altro avvistamento in Adriatico risale all’agosto del 2002, al largo di Senigallia.
Foto: Tilen Genov (Morigenos)
Per maggiori informazioni:
Morigenos - avvistamento megattera 2009
Reeves R., Notarbartolo di Sciara G. (compilers and editors). 2006. The status and distribution of cetaceans in the Black Sea and Mediterranean Sea. IUCN Centre for Mediterranean Cooperation, Malaga, Spain. 137 pp.
Frantzis A., Nikolaou O., Bompar J.-M., Cammedda A., 2004. Humpback whale (Megaptera novaeangliae) occurrence in the Mediterranean Sea. The Journal of Cetacean Research Management 6(1): 25-28.
Bearzi G., Holcer D., Notarbartolo di Sciara G. 2004. The role of historical dolphin takes and habitat degradation in shaping the present status of northern Adriatic cetaceans. Aquatic Conservation: Marine and Freshwater Ecosystems 14: 363-379.
Pubblicato da Giovanni Bearzi a 07:09
18 February 2009
"Ho avuto molti incontri con i cetacei, ognuno unico ed emozionante, ma uno mi è rimasto particolarmente impresso. Ero nel canale della Manica e c’era calma piatta quando una balenottera, probabilmente un esemplare giovane, si è avvicinata incuriosita fino a strofinarsi alla prua. E’ rimasta accanto alla barca per mezza giornata, lasciandosi ammirare in tutta la sua maestosità e scrutandomi ogni tanto con i suoi occhi enormi così profondi, come se avesse capito che il mare è un po’ anche casa mia.
Lo studio e la tutela di questi animali sono per me attività importantissime che dovrebbero essere sostenute con forza. Ritengo che l’Istituto Tethys, con cui sicuramente mi accumuna il grande amore per il mare e la passione per il nostro lavoro, stia facendo un lavoro eccezionale. Da oltre vent’anni combatte la sua battaglia per la tutela del mare e dei meravigliosi animali che lo abitano - una missione che apprezzo profondamente e per la quale vorrei fare a Tethys i miei più calorosi auguri: vento in poppa!"
-- Giovanni Soldini
Vedi la pagina di Giovanni Soldini sul sito di Tethys
Pubblicato da Giovanni Bearzi a 06:01
17 February 2009
A new paper published on Science, has examined the scientific evidence for the assertion that ‘commercial fisheries are negatively impacted by whales in tropical breeding areas’ and that ‘reducing the number of baleen whales in the oceans would improve fisheries because whales eat fish that are caught for human consumption’.
The study, based on ecosystem models, examines the potential increase in the biomass of commercially important fish stocks that would result from a reduction in whale abundance in the Northwest African and Caribbean ecosystems.
Researchers have demonstrated that even a complete eradication of whale populations in tropical waters would not lead to any considerable increase in fish populations. “Our models unequivocally show that removing whales would not significantly increase the amount of commercially valuable fish,” said Leah Gerber, one of the authors, “Instead, we found that fishing is having a far greater bearing on the health of the fish stocks in the region...”
Daniel Pauly, a well-known fishery scientist and co-author of this paper, added “The assertion that fish supply is in peril is legitimate, but the problem is resolved with better management, not whaling”.
Gerber L.R., Morissette L., Kaschner K., Pauly D. 2009. Should whales be culled to increase fishery yield? Science 323: 880-881.
For more information:
Pubblicato da Silvia Bonizzoni a 06:43
16 February 2009
The Steering Group of the Cetacean Alliance (which includes Tethys President Giovanni Bearzi and Tethys Honorary President Giuseppe Notarbartolo di Sciara) gathered in Milan to discuss a thick agenda of cetacean conservation issues.
On the second day of the meeting, the group was joined by Vangelis Paravas, President of MOm (Hellenic Society for the Study and Protection of the Monk Seal) and Giorgos Paximadis, Marine Officer of WWF Greece. The group discussed future activities related to the "Kalamos Call", an urgent call for the conservation of one of the last strongholds of Mediterranean common dolphins, as well as general strategies for the conservation of cetaceans in Greece.
The meeting was extremely productive and it confirmed that joining forces for a common cause - based on ongoing and fruitful collaboration - is a great way of getting things accomplished.
Cetacean Alliance aims to develop synergies and create opportunities for collaboration among individuals and organizations determined to protect cetacean populations living in the Mediterranean Sea. The alliance includes research and conservation NGOs with bases in Austria, Croatia, Germany, Greece, Italy, Slovenia, Spain, Switzerland and the U.K, representing a collective membership of over 100,000 supporters.
For more information:
Pubblicato da Giovanni Bearzi a 08:50
15 February 2009
For the first time, spectacular aerial footage captured by the BBC shows elusive narwhal during their annual migration north from the west coast of Greenland to their summer feeding grounds in the fjords and bays beyond Lancaster Sound (Canada).
The cetaceans have been filmed from a helicopter. They were swimming in groups of 20 or 30, in perfect unison as they surface for air.
The BBC video
For more information:
Pubblicato da Silvia Bonizzoni a 11:35
14 February 2009
Two papers on cetacean mothers have been recently published.
One investigated the role of menopause and reproductive senescence in a long-lived social mammal such as killer whales. The study reports that older mothers appear to be better mothers, producing calves with higher survival rates, than younger less-experienced moms.
"Older females may be more successful in raising young because of maternal experience, or they may allocate more effort to their offspring relative to younger females", researchers said.
This result is consistent with similar studies of other mammals; the presence of grandmothers may positively influence survival of juveniles at a critical life stage. The study also confirmed that menopause and long post-reproductive lifespans are not prerogatives of humans.
The other study focused on the whale mothers who teach their babies where to eat. Thanks to genetic and chemical analyses, researchers show that the right whale teach to their calves the location of feeding grounds during a long migration through the South Atlantic Ocean.
Researchers are now linking this result to the ocean present situation and they are raising concern about whales ability to find new places to feed if climate change is disrupting their traditional feeding areas.
Southern Right whale and calf, by Genevieve Johnson (earthOcean)
For more information:
Ward E.J., Parsons K., Holmes E.E., Balcomb K.C., Ford J.K.B. 2009. The role of menopause and reproductive senescence in a long-lived social mammal. Frontiers in Zoology 6: 4. doi:10.1186/1742-9994-6-4
‘Mother whales teach babies where to eat: can Southern right whales adapt if food becomes scarce?’
Pubblicato da Silvia Bonizzoni a 10:13
08 February 2009
A 'special' researcher is going to join the Ionian Dolphin Project team next spring: Tilen Genov, President of Morigenos.
When he was about 8, Tilen had been the first adopter of a bottlenose dolphin in the context of a campaign launched to support research by Tethys around Losinj, Croatia. Since then he has been a frequent guest at the Losinj field station, initially with Tethys and then with BlueWorld.
Having learned much through contact with researchers and direct observation, Tilen eventally created his own organization in Slovenia and started doing dolphin research with his team.
Tilen just published a paper summarizing his findings on bottlenose dolphins along the Slovenian and adjacent coasts.
Tilen will work with Tethys researchers in the context of "Delphi's Dolphins", the new dolphin research and conservation project in the Gulf of Corinth, Greece.
Morigenos, together with Tethys and various other cetacean research and conservation NGOs, is member of the Cetacean Alliance.
Pubblicato da Giovanni Bearzi a 09:25
07 February 2009
Nei giorni trascorsi a Galaxidi per sistemare la nuova base di ricerca dello Ionian Dolphin Project, mi è capitato di dover ordinare un vecchio ed enorme faldone dei protocolli di ricerca usati dall’IDP durante la sua lunga storia: protocollo per la navigazione, protocollo per il comportamento, protocollo per i survey da terra, protocollo per la raccolta di scaglie, protocollo per la gestione della base, protocollo per la fotoidentificazione, protocollo per il matching, protocollo per le biopsie, protocollo per gli animali spiaggiati, protocollo per i turni di cucina etc. etc.
Tra i vari plichi, uno si è distinto in modo particolare: ‘Il protocollo del perfetto protocollista’, redatto dall'ex-collaboratore Francesco Quondam in una giornata di sole nella vecchia base di Episkopi, probabilmente mentre i volontari e gli altri ricercatori erano fuori in mare.
Forse un pizzico di ironia o una velata critica nei riguardi del progetto più 'protocolloso' del globo terracqueo?
Dal protocollo per il perfetto protocollista (giugno 1999)
- non perdere mai l'occasione per un perfetto protocollino (carpe diem)
- pensare al protocollo prima che ce ne sia bisogno (prevenire è meglio che curare)
- non aspettare che siano altri a stendere i protocolli
- man mano che i protocolli diventano obsoleti, aggiornarli
- computer, meglio se portatile, in modo da poter seguire qualsiasi ispirazione
- moltissimi fogli A4
- sadismo e pedanteria
Regole per la stesura:
- accendere il computer
- scegliere adeguatamente il carattere, meglio se Times, in modo da sembrare più buoni
- attenzione alle spaziature e all’interlinea: il protocollo deve essere facilmente leggibile
- non lasciarsi prendere da nessuna remora
Verifiche obbligatorie ad intervalli regolari:
- controllare la perfetta applicazione del protocollo
Verifiche obbligatorie a date predefinite:
- 15 luglio: protocollo fotoID
- 30 luglio: protocollo navigazione
- alle idi di marzo: protocollo LOP
- tra le 5 e le 6 di mattina del 19 agosto: protocollo biopsie
- durante ogni primo quarto di luna: protocollo behaviour
- durante la luna dei vitelli che cambiano il pelo: protocollo scale sampling
Pubblicato da Silvia Bonizzoni a 07:16
06 February 2009
Confermata l’ipotesi che i più antichi antenati dei cetacei attuali avessero origini terrestri.
In Pakistan sono stati rinvenuti i resti di un nuovo Protocetide, il Maiacetus inuus, un animale vissuto 49-37 milioni di anni fa che conduceva una vita semiacquatica. Gli scheletri appartengono a una femmina lunga 2,6 metri con il suo feto e a un altro esemplare maschio leggermente più lungo.
Di particolare interesse è la posizione del feto nel corpo della madre. Il piccolo, quasi pronto per nascere, è in posizione cefalica e ciò differisce dagli attuali cetacei che invece si presentano ‘di coda’. Secondo i ricercatori questo suggerisce che il M. inuus, non essendo ancora completamente adattato alla vita acquatica, fosse costretto a partorire a terra. Questa caratteristica è coerente con la morfologia scheletrica, che consentiva all'animale di sostenere il suo peso sulla terra. Precedenti teorie sull’appartenenza dei Protocetidi al mondo anfibio vengono quindi scalzate dalla recente scoperta.
Giuseppe Notarbartolo di Sciara, Presidente onorario di Tethys, intervistato dal Corriere della Sera, ha commentato così la notizia: “Conosciamo così poco sulla storia evolutiva dei cetacei che la scoperta di un fossile di cetaceo con il feto è straordinaria, unica. La nascita è un momento drammatico nella vita dei cetacei attuali, perché partoriscono nell’acqua un piccolo che respira aria. E’ stato un giro di boa importante nella loro evoluzione. Questa scoperta è come una finestra aperta su uno stadio intermedio delle modalità di riproduzione. E’ come il fotogramma di un film”.
Immagine: Scheletro di una femmina adulta di Maiacetus inuus (ossa rosa) e del suo feto (ossa azzurre)
Gingerich P.D., ul-Haq M., von Koenigswald W., Sanders W.J., Smith B.H., Zalmout I.S. 2009. New Protocetid whale from the Middle Eocene of Pakistan: birth on land, precocial development, and sexual dimorphism. PLoS ONE 4(2): e4366.
ABSTRACT: Protocetidae are middle Eocene (49-37 Ma) archaeocete predators ancestral to later whales. They are found in marine sedimentary rocks, but retain four legs and were not yet fully aquatic. Protocetids have been interpreted as amphibious, feeding in the sea but returning to land to rest. Two adult skeletons of a new 2.6 meter long protocetid, Maiacetus inuus, are described from the early middle Eocene Habib Rahi Formation of Pakistan. M. inuus differs from contemporary archaic whales in having a fused mandibular symphysis, distinctive astragalus bones in the ankle, and a less hind-limb dominated postcranial skeleton. One adult skeleton is female and bears the skull and partial skeleton of a single large near-term fetus. The fetal skeleton is positioned for head-first delivery, which typifies land mammals but not extant whales, evidence that birth took place on land. The fetal skeleton has permanent first molars well mineralized, which indicates precocial development at birth. Precocial development, with attendant size and mobility, were as critical for survival of a neonate at the land-sea interface in the Eocene as they are today. The second adult skeleton is the most complete known for a protocetid. The vertebral column, preserved in articulation, has 7 cervicals, 13 thoracics, 6 lumbars, 4 sacrals, and 21 caudals. All four limbs are preserved with hands and feet. This adult is 12% larger in linear dimensions than the female skeleton, on average, has canine teeth that are 20% larger, and is interpreted as male. Moderate sexual dimorphism indicates limited male-male competition during breeding, which in turn suggests little aggregation of food or shelter in the environment inhabited by protocetids. Discovery of a near-term fetus positioned for head-first delivery provides important evidence that early protocetid whales gave birth on land. This is consistent with skeletal morphology enabling Maiacetus to support its weight on land and corroborates previous ideas that protocetids were amphibious. Specimens this complete are virtual ‘Rosetta stones’ providing insight into functional capabilities and life history of extinct animals that cannot be gained any other way.
Per maggiori informazioni:
Pubblicato da Silvia Bonizzoni a 07:43
05 February 2009
The Universe in a Single Atom
The Convergence of Science and Spirituality
by H.H. the Dalai Lama
Morgan Road Books, New York
Modern scientists often seem to take pride in showing contempt for religion and spirituality. Some call themselves atheists, make fun of spiritual leaders and profess the superiority of modern science over thousand-year-old spiritual traditions.
Intelligent and cultured colleagues may talk about religions as if all these were basically ways of addressing popular craving, elaborated strategies for manipulating the masses, imaginative scenarios of made-up gods and deities, and the like. Religions are often referred to, or thought to be, cumbersome apparatuses dealing with one or more gods to be adored, with no proof whatsoever of their existence. Therefore, something worth laughing about by those who believe in Science (in fact, just a different kind of deity).
A striking example of limited familiarity with the subject of some scientists' contempt is the fact that buddhism is often paired with theistic religions. Some may even think that Buddha is the god adored by buddhists, which is quite interesting considering that the Buddha - a man who lived in India some 2500 years ago - can be regarded as one of the earliest true scientists in the modern sense.
Buddhism is not a theistic religion but rather a spiritual tradition or a psychological philosophy. What makes it 'look' as a religion is probably its very old age and its many popular manifestations and coloured embellishments that - depending on areas and lineages - have happened to include god-like statues and church-like buildings. The Buddha, however, strongly recommended to adore nothing (particularly not himself), have no attachment to icons and only rely on one's own experience.
I have always been attracted by buddhism for the same reasons I am attracted by science: it is based on observation. While science is a way of exploring the outside world, buddhism is a way of exploring the world inside, i.e. the way our minds work. The method is quite precisely the same and it has a similar affection for unbiased observation and a similar dislike for dogma. Buddhism transcends and avoids theology and it covers both the natural and the spiritual, seeing all things, natural and spiritual, as parts of the same scenario.
Of the many modern scientists who realized an affinity between science and buddhism, Einstein is probably the most famous. One of his oft-quoted sentences goes: ‘If there is any religion that would cope with modern scientific needs it would be Buddhism’. Calling buddhism a 'religion' is probably a simplification here, and I think that this term is misleading as it creates a separation that does not need to exist. I would be equally comfortable calling buddhism a science, a science of the mind that has developed and described its own ways (the dharma) through introspection - i.e. observation directed inward.
The most fundamental way of being a buddhist (some would argue: the only way) is to simply stay still, look at how the mind works, and 'take note'. Through repeated observation of one's own mental mechanisms (much more complex and difficult to deal with than one could ever imagine), one sees what is really going on there. To me, this looks similar to repeatedly observing the natural world and understanding what is going on outside, with no attachment to the ‘official’ scientific knowledge and a fresh beginner’s mind.
February’s Book of the Month is ‘The Universe in a Single Atom: The Convergence of Science and Spirituality’ by the Dalai Lama. This book addresses some of the points above in a much better way than I could possibly do. As it is written by a man from Tibet who embodies an ancient tradition, some sections may be a bit difficult to read or understand, particularly by those who are not familiar with buddhist teachings and terminology. Still, this is an amazing book aimed to build bridges between modern science and buddhism and it shows how these might be integrated. I would recommend it to anyone who - perhaps for good reasons - has lost respect or interest in religion and spirituality.
Note: this item is open to discussion in the Facebook page of Tethys (Discussion board: Science and buddhism)
Titolo italiano: ‘L’abbraccio del mondo: Quando scienza e spiritualità si incontrano’ Sperling & Kupfer Editori.
Pubblicato da Silvia Bonizzoni a 07:01
04 February 2009
In the recent paper ‘Reconsidering the science of scientific whaling’ Peter Corkeron, a renowned cetologist, reviewed the data obtained in the last years by Japanese scientific whaling research.
From a scientific standpoint, Corkeron analyzed every single aspects of this lethal research, and provided evidence on why this technique is useless, simplistic, unsophisticated and problematic.
Corkeron P.J. 2009. Reconsidering the science of scientific whaling. Marine Ecology Progress Series 375: 305-309.
ABSTRACT: Scientific whaling is one of the most publicly contentious applications of marine ecological research today. An evaluation of the second phase of Japan's Institute of Cetacean Research (ICR) program in the western North Pacific (JARPN II) is soon to be conducted under the auspices of the Scientific Committee (SC) of the International Whaling Commission (IWC). Previous IWC SC reviews identified serious problems with the programs, yet reached inconsequential conclusions, and the JARPN II review is the first under a new format. The basic design of this study - forestomach sampling coupled with acoustic and trawl surveys for prey - is an unsophisticated approach to investigating the foraging ecology of Balaenoptera spp. Published results of the JARPN II feasibility study demonstrate problems with the execution of field work. Data analyses were simplistic. Non-lethal studies into the foraging ecology of Balaenoptera spp., using far fewer resources, have produced more definitive information. The recent changes in the IWC SC review process should result in unambiguous advice on how to improve the design of JARPN II. If the review recommends improvements that are not acted upon by the program's proponents, the IWC may need to decide whether the JARPN II program can be considered to be scientific research under Article VIII of the International Convention for the Regulation of Whaling.
Pubblicato da Silvia Bonizzoni a 06:13
03 February 2009
Less than two months ago, Tethys launched its Facebook page.
Today the page has reached 300 fans!
Interestingly, 65% are women and 35% men. Someone said that environmental awareness and care for nature is more widespread among women, inter alia because of their innate interest in preserving a healthy planet for their children. Could this be the reason?
Pubblicato da Giovanni Bearzi a 17:44
02 February 2009
A new study on dolphins registered elaborate and complex feeding behaviour to turn a cuttlefish into a soft, chewy snack.
In the Upper Spencer Gulf in South Australia, researchers observed and recorded a wild female Indo-Pacific bottlenose dolphin (Tursiops aduncus) repeatedly catching, killing and preparing cuttlefish for consumption using a specific and ordered sequence of behaviours.
Cuttlefish were herded to a sand substrate, pinned to the seafloor, killed by downward thrust, raised mid-water and beaten by the dolphin with its snout until the ink was released and drained. The deceased cuttlefish was then returned to the seafloor, inverted and forced along the sand substrate in order to strip the thin dorsal layer of skin off the mantle, thus releasing the buoyant calcareous cuttlebone.
As the researchers said ‘this behaviour is a dramatic example of how dolphins, with their relatively unspecialised morphology, can utilise behavioural flexibility to tackle prey items that require substantial handling before consumption...’
Stages of prey handling of giant cuttlefish (Sepia apama) by Indo-Pacific bottlenose dolphin
For more information:
Finn J., Tregenza T., Norman M. 2009. Preparing the perfect cuttlefish meal: complex prey handling by dolphins. PLoS ONE 4(1):e4217.
Pubblicato da Silvia Bonizzoni a 18:05
01 February 2009
We are leaving Corsica due to bad weather conditions forecasted for the next week and we plan to resume the survey in 8-10 days, being based in Albenga (Villanova Airport).
In the figure you see the striped dolphin sightings in white and the sun fish (Mola mola) sightings in purple. We have also seen a few bottlenose dolphins (4 sightings) and one beaked whale.
The results so far are quite interesting, the absence of sightings of fin whales and other species (Risso's dolphins, pilot whales, sperm whales) needs further consideration and raises new research questions. The high number of Mola mola will probably allow a draft estimate of their density, even if we have no idea of G(0) for this fish species.
Eventually, we have finished the south west block, most of the east block and there is some work left to do in the north, north-west block.
Simone, Giancarlo and Nino
Pubblicato da Giovanni Bearzi a 12:19