Dolphins Tenerife

European and American scientists have found a revolutionary way to study the effect of high-intensity sounds in sea mammals such as whales and dolphins. The researches stated that the growing in shipping, petroleum exploitation and military maneuvers have increased the noise in the oceans in the last years.

The major part of their study was focused in the effect of sonar transmitters on cetaceans, and they expect that the navy can take advantage of the software they have designed to decide when it is safe or not to use the sonar. The results have been published on the Public Library of Sciences One Magazine (PLoS).

The scientists involved in this study are from the University of California – San Diego (USCD) and the Zoo Kolmården (Switzerland). They have created a technique to observe the effects of noise on sea mammals developing a state-of-the-art software program that includes X-ray computed tomography.

Using this technology, scientists can simulate the sounds emitted by a virtual cetacean and study the interactions between the sound and the mammal. Besides, the program allows researchers to study 3D images of the head of cetaceans such as the Cuvier’s beaked whale, a species which is affected by acoustic contamination generated by sonar transmitters.

“Our software can be used to research cetaceans’ mechanism of sound emission and reception and to simulate the exposure of dolphins and whales to high levels of acoustic contamination, as well as to try different noise reduction strategies, which is impossible to do with live animals”, explained Professor Petr Krysl, from the UCSD who developed the software program for this study. “We believe that our study can help us to understand more about dolphins and even to find a solution to the potential negative effects of high-intensity sounds in sea animals”, he added.

Humans create relevant amounts of sound and noise in the oceans all over the world, and this may cause serious problems to marine life because many sea animals use sound as a sonar transmitter because it is more effective than eyesight in the water. Dr. Krysl said that “the study was focused in the Cuvier’s beaked whale because many of these cetaceans have been found beached and dead due to military sonar transmitters’ operations. Our findings about the hearing system in Cuvier’s beaked whales can be applied in bottlenose dolphins and we believe that in any kind of toothed whales and even other sea mammals”.

Dr. Krysl commented that the project expands the knowledge about the biology of sea mammals. The sense of hearing is essential in underwater life because it is used for hunting, orientation and communication. However, he said that the main purpose of this research was to learn about the effect of military sonar transmitters in dolphins. The professor explained that the navy wanted to know if sonar transmitters were safe and if it was possible to reduce their effect on sea life. For that reason, the study was financed by the Chief of Naval Operations (CNO) of the United States of America.

Professor Krysl added that his team is going to continue with this research in Cuvier’s beaked whales and they will include tests with bottlenose dolphins too. They are also planning to improve the models to study the trajectory that sounds make from the water to the inner part of the ear of cetaceans. These projects are intended to accomplish several goals of the navy of the United States which is trying to have a comprehensive knowledge about the demography, the limits of acoustic exposure and the strategies to reduce the effect of noise in sea mammals.

Two specimens of humpback whales were seen few days ago about 900 meters from the north coastline of Alicante, Spain, between the San Antonio and the San Martín capes.

According to the Ministry of the Environment, surveillance personnel from the marine reserve in San Antonio Cape saw two humpback whales the 14th of September. The cetaceans where swimming heading south.

The surveillance personnel watched the whales for thirty minutes and during that period, the whales made three spectacular jumps that where caught by the cameras.

According to the Ministry of the Environment, the sighting of this kind of whales is an exceptional event, due to in the last two centuries there were registered only 15 sightings of this species in the Mediterranean Sea.

Humpback whales have been seen near the coast of the Balearic Islands, Catalonia, Málaga and in the Algeciras Bay, where about a month ago a female humpback whale was seen with her offspring.

The humpback whale is a protected species that lives all around the world, but it is rarely seen in the Mediterranean Sea. However, since 1990 the number of sightings of this species has increased maybe due to the growing of the North Atlantic humpback whales’ population and the increase in the number of whale watchers.

The exceptional event coincided with the presence of several fish shoals in the area, which are the food of these cetaceans.

During this summer season, whale watchers reported the sighting of several finback whales which are more common in this area of the Mediterranean Sea.

The Ministry of the Environment conducts regular whale watching expeditions in this area from the air and from the sea, as part of their cetaceans’ detection program.

The first cetaceans’ aerial census made by the Council of Andalusia this year showed a total of 68 sightings.

This is the first aerial census of cetaceans made this year by the Spanish Ministry of the Environment in the framework of the sustainability program for the marine environment of Andalusia. The Ministry of the Environment has been conducting annual campaigns of whale and dolphin registering since 2005 to monitor and cense the cetaceans’ populations near the coast of Andalusia. These campaigns consist on several monitoring activities form the air and from the sea covering the coastline and deep sea.

For this aerial census, the authorities have made a series of flights during spring and autumn, which have been an effective tool to locate cetaceans, because they allow to cover wide surfaces in short time and to monitor areas far away from the coastline, where it becomes difficult to travel using other means of transport. Each flight serves to monitor a pre-established area in each one of the coastal municipalities and also in the deep sea to a distance about 30 miles.

The first stage of the 2010 campaign was made between May and June. A total of 13 flights were made covering 8,484 kilometers (about 4,533 miles). From the total, 5,924 kilometers where made looking for cetaceans at 1,000 feet altitude (about 333 meters above the sea). From the total number of sightings Málaga had 31 and Cádiz 23, being the provinces that have the higher numbers of sightings.

The 65% of the sightings belonged to common and striped dolphins. Apart from this, the researches watched bottlenose dolphins, pilot whales and Risso’s dolphins as well. What is more, the aerial census allowed the researchers to watch some cetacean species less common in the coastline of Andalusia such as the Cuvier’s beaked whale or the killer whale. Likewise, finback whales were watched two consecutive days in front of the coast of Málaga and in the Strait of Gibraltar.

With regards to the data collection from the sea, the whale watching ships monitor the specimens all over the year covering the Andalusia coastline from two to four times a year. The onboard research activities allow the collection of information about young specimens and babies, which is especially useful to determine the species of some dolphins and the exact number of them, which is impossible to do from the sky.

The cetaceans’ monitoring in the coastline of Andalusia carried out by technicians from the marine environment sustainability program, gathers the information obtained from the sky and from the sea, to elaborate a census that allows a better understanding and management of the marine life, specially regarding the conservation of these species.

In spite of the fact that Japan is suffering one of the worst economic crisis in the last years, the representatives of the Japanese government that attended the International Whaling Commission meeting the 10th of March, 2009 in Rome, defended their millionaire “scientific” whaling program.

This is an activity highly criticized by the international community and barely supported by Japanese taxpayers.

Last February, the Japanese government announced a decrease in their exports near the 45% in relation with the same period of the previous year, while the main Japanese industries were reducing operating costs and jobs, and the gross domestic product (GDP) fall 3.3% in the last four-month period of 2008, which is the double of the GDP reduction in the United States in the same period.

However, the Japanese government refuses to consider the closure of its whaling program in the Antarctica, in spite of its cost that is over one billion yens, which has to be financed by Japanese taxpayers.

The “scientific” whaling program the Japanese government conducts claiming false scientific reasons is an economic disaster, said Celia Ojeda, responsible for the Greenpeace’ oceans campaign.

That week in Rome it was debated the future of the International Whaling Commission. Greenpeace considers that the only possible future for this commission is to work seriously in the protection of the whales’ populations, to promote non-lethal studies of them and to invest in an effective conservation of marine life.

“Japan insists on continuing with their program, but they should take into account that it is unnecessary another year of whales’ hunting that puts in danger the marine environment and wastes the money of the taxpayers”, concluded the representative of Greenpeace.

Apart from the 1.2 billion yens spent per year in this program (about 10 million Euros) using public money, the Government of Japan also spends billions of yens in international aids to gain votes that support them in the International Whaling Commission.

Japanese fishermen have started last Thursday the dolphins’ hunting season in the region of Taiji, the coastal town that is shown in the documentary film “The Cove”, which was awarded with an Oscar.

About twenty fishermen who set sail earlier in the morning that day retuned with their hands empty few hours later, informed an officer of the Taiji fishing community, who refused to give his name because he mistrusted foreign press. The fishermen from this coastal area have been hunting dolphins for centuries, but nowadays they are criticized because the hunting is considered cruel and apart from that, the meat of these mammals has high levels of mercury being unsuitable for human consumption.

In Taiji, fishermen chase dolphins near the coastline hitting the water with metal tubes and once they are captured, they are sold for exhibitions, zoos or as food. Other Japanese fishermen’s towns hunt dolphins directly in deep sea. These dolphins are not an endangered species and their hunting is regulated by National Fisheries Agency of Japan.

The dolphins’ hunting in Taiji was the main theme of the documentary film, The Cove, that shot this activity last year using hidden cameras to show how dolphins where killed by the fishermen. The release of this film last summer opened an international discussion about these practices and the condemnation of the environmentalist organizations.

A striped dolphin was taken last week to the Centro de Recuperación de Especies Marinas Amenazadas – CREMA (recovery centre for endangered marine life), which is part of the Aula del Mar museum located in Malaga’s port, Spain. The dolphin was found last week in a beach called “Peñoncillo” located in Torrox-costa according to the information provided by representatives of the centre.

The rescued cetacean is a young male striped dolphin (Stenella coeruleoalba) that was found beached without visible injuries but sick. The veterinarians of the endangered marine life recovery centre are conducting a series of clinical studies to determine the disease of the animal. The results will be received by the end of this week, said the veterinarian in charge of this dolphin, Juan José Castillo.

What is more, representatives of the museum Aula Del Mar said that the health condition of the dolphin is serious but stable, considering the bad conditions dolphins usually present when they are found beached. The specimen is receiving intensive care in the sickbay pool the CREMA has in its facilities.

However, the veterinarians of the centre have said that they cannot determine the period this dolphin will be hospitalized because it is a species that can get worse easily, and they cannot assure that the dolphin will progress well. On the other hand, they say that the dolphin needs to return as soon as possible to the sea, because this species cannot be kept in captivity a long time because it distresses easily.

On average, from six to twelve dolphins are found alive beached on the coast per year. From the total, two or three usually have to be taken to the recovery centre. “Unfortunately, we don’t have precise numbers about this phenomenon yet” said the veterinarian.

The two beluga or white whale (Delphinapterus leucas) specimens that live in the l’Oceanogràfic aquarium located in Valencia, Spain, emit different sounds which are being studied by the personnel of the centre. According to the researchers, the analysis and study of these sounds “is impossible to be conducted in their natural environment, but here at the aquarium is very easy thanks to audiograms”.

The research department of the l’Oceanogràfic has been investigating the bio-acoustic function of the belugas since their arrival in 2003 from an aquarium located in Mar del Plata, Argentina. “In order to maintain animals in captivity, we are obliged to have an associated research project that justifies that measure. In the case of the white whales, we are investigating the varied repertory of sounds these cetaceans have, which makes them being known as the ‘canaries of the sea’”, said Antonio Estéban, responsible for the department that is conducting the study about the belugas’ language.

The fact that these marine mammals are emitting sounds is a proof of their good health condition and their adaption to their new habitat in the aquarium of the l’Oceanogràfic. Estéban explained that “when this species feel threatened their acoustic activity reduces dramatically. When Yulka and Kairo arrived to the l’Oceanogràfic they didn’t emit any sound. After three weeks, they started emitting sounds again and nowadays they communicate as they used to do in the aquarium of Mar del Plata, where they didn’t live in captivity.

It was important for the study to check if the belugas had changed their behaviour after being relocated. For that reason, the researches took two aspects into account, “on the one hand, we paid attention to the number of sounds they emitted per hour and, on the other hand, the type of sounds they emitted, because they have a large repertory of sounds”.

The sounds these cetaceans emit have two main functions: the first one is for social communication, which is indispensable to keep the group’s cohesion and to establish hierarchies in the group and to individualize family units. The second function is echolocation, because these cetaceans use the sounds as a sonar transmitter to find their preys. “Depending on the sound, we observe the behaviour attached to it”, said Estéban. This study can contribute to the lack of knowledge about the biology of this species. The results of this project will be used in future researches on belugas in their natural environment because “these studies are impossible to be carried out in their natural environment, but here at the aquarium it is very easy because we can use audiograms”, added Estéban.

In 2007 it was held at the “Ciudad de las Artes y las Ciencias” in Valencia an international workshop about belugas in natural and artificial environments. During the event, scientists agreed that “there is little information about the Delphinapterus Leucas to assure their conservation”, said Estéban, and he added that “we concluded that if we make the necessary researches before they become an endangered species, like it happened with the Iberian liynx, we would be able to have the necessary information to protect them”. This was the first time that research teams that had been working in the study of the white whales in artificial and natural environments exchanged information about the results of their researches.

The Delphinapterus leucas dolphins, commonly called belugas or white whales, live in the Arctic area, near the North Pole where there is a huge acoustic contamination. The aquarium of the l’Oceanogràfic imitates the natural environment of walrus and belugas with rocks and ice blocks. Besides, these animals that are very social ones are provided with the necessary stimulus to feel comfortable in the artificial habitat, sharing with seals or having toys that stimulate their instincts. “The belugas have the capability to notice when there are children looking at them and they love interacting with kids”, said Pilar Tormo, responsible for the press department.

The l’Oceanogràfic has developed a series of breeding and research programs. A seal, a flamingo, a shark, two bottlenose dolphins and two Humboldt penguins were born in the facilities of the aquarium since its opening in 2003.

The major achievement in term of breeding programs was achieved the 2nd of November, 2006, when the belugas had their first baby, which was the first specimen born in captivity in Europe. The offspring only lived 25 days, which was unfortunate but expected by the scientists due to the captivity conditions. However, the birth of this cetacean in captivity was very important for the research project aimed at the conservation of the white whales, because it provided information about their biology and the experience for future births in captivity. “It is normal that the first newborn in captivity die, but the fact that the female beluga got pregnant in captivity shows that the conditions of the aquarium are good for their reproduction”, concluded the chief director of the research.