Entries in #wildlife (23)

Tuesday
May162017

Tenerife - Reconnect With  Nature

“Keep close to nature’s heart…and break clear away, once in a while, and climb a mountain or spend a week in the woods. Wash your spirit clean” - John Muir

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Tuesday
Feb212017

Exceptional Luck On Peter  Pan

As we cast off I remembered that I'd been rather spoilt on my first trip out and expected that this one would probably be rather less eventful. I really couldn't have been more wrong.

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Monday
Jan162017

One Week In South Tenerife!

My first ever week on the Island of Tenerife is coming to a close and I will be sad to go home. I chose the project as I am considering doing a Master’s degree in Marine Conservation.

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Monday
Jul252016

My Trip As A Marine Biology Student 

"I participated on the Whale and Dolphin Conservation project for a week. After completing my first year of Marine Biology at University, I was looking for a trip to give me inspiration and let me see past all the exams and coursework and know that it does lead to something greater"

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Monday
May162016

Cetacean Conservation: Whales and Dolphins Need Protecting!

The International Union for Conservation of Nature (IUCN) recognizes a total of 87 cetacean species - 15 are ranked as “Critically Endangered”, “Endangered” or “Vulnerable”, and 45 ranked “Data Deficient”. The overall conservation status of cetaceans and their environment is being monitored, but why do they need conserving?

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Wednesday
May042016

Conscious Cetaceans: The Intelligence of Non-human Persons

We base our understanding of animal intelligence on human intelligence. But what is intelligence? Could a species be superior to humans?

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Monday
Apr252016

The Weird Yellow Fruit

The quest to discover what this fruit is?! Anyone know?

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Monday
Apr112016

Charismatic Cetaceans: Why We Love Whales And Dolphins - A Blessing And A Curse

Welcome to this four part series about cetaceans! Cetaceans include whales, dolphins and porpoise and their conservation is the main focus of our project here in Tenerife. But why do we humans love cetaceans so much? How do cetaceans interact with their environment? Why have cetaceans been given rights as non-human persons? Why do cetaceans need protecting? Find out everything in our four part Cetacean series!

Whales and dolphins are among a select group called ‘charismatic megafauna’. This means they are big animals with a cute smile - and humans simply love that! Ever wondered why the World Wild Fund for Nature (WWF) logo is a giant panda? Because it is a cute big fluffy animal with a smile! Okay, it is a little more complicated, but only just.

pixabay | mikakapturWe humans like things to look nice and be able to relate to them. Looks matter! It is not just about swiping left or right on Tinder. It has been scientifically proven we are hard-wired to respond positively to “cute” – big eyes, round heads, short snouts – and it translates directly into dollar bills (or the currency of your choice). Dolphins are the perfect example of “cute”. Their fixed smile give them a friendly and happy appearance and their anatomy is non-threatening; for example their pectoral fins and streamlined body are much like our arms and torso. Compare this to the image of a spider with eight crawling hairy legs and alien-like eyes. With the exception of some little boys’ obsession with creepy crawlies, people prefer dolphins over spiders.

Relatability matters! We long to travel the world barefoot and jump out of flying contraptions… but when it comes down to it, we are creatures of habit, enjoying familiar situations. We like animals to be similar to us and share intelligence, behaviours and social structures. The more similar, the more we identify with them, and the more we feel a moral duty of care to protect them. Dolphins are very intelligent social creatures with a curious nature. We relate to them when listening to their clicks and whistles, watching their playful behaviour such as jumping and playing, blowing bubbles or playing with objects.

flickr | Ania MendrekCetaceans check the boxes: good aesthetics and relatability and voilà, a charismatic megafauna with high economic value to humans. Whales were hunted for their meat, blubber and oil. As science developed it became apparent that these were intelligent social creatures and after the 1970s Save the Whale campaign they were seen as an environmental icon and “gentle giants” who roam the seas peacefully. The whale songs are even used as relaxing meditation music!

flickr | Ezra Freeloveflickr | Rennett StoweWhales and dolphins became part of pop-culture with Flipper in the 1960s and Free Willy in 1993. This new interest in cetaceans sparked a growth of marine parks and aquariums. Belugas (Delphinapterus leucas) with their unique white colour and their range of facial expressions, were first to be held in captivity. Nowadays, bottlenose dolphins (Tursiops truncatus) are the most common species in marine parks due to their intelligence, trainability, playfulness and friendly appearance as well as the striking killer whales (Orcinus orca). However, in captivity, cetaceans are lacking space and the resemblance to their wild habitat. In the United States the legal requirements for killer whale tank is 15 metres in diameter for two individuals, whereas in the wild an orca can travel up to 160 kilometres a day! As a result, cetaceans can have reduced life expectancies, high levels of stress and even psychosis. Note: If you haven’t yet, you need to watch the critically acclaimed 2013 documentary ‘Blackfish’ which shows the reality behind the tank-life.

It doesn’t take an expert to see that cetaceans are too big and intelligent to be suitable for life in a tank. In some countries dolphins have even received the status of non-human persons, giving them special rights, including it being morally unacceptable to keep them in captivity.

flickr | ใใ†ใ“Luckily, a cetacean’s value is not limited to ticket-sales at a marine park. As charismatic megafauna they easily capture public and media attention, and spark political interest, therefore being more likely to receive protection under the Endangered Species Act and funding for their conservation.

Often, they are an essential part of marine ecosystems as they have a high trophic level (meaning they are on top of the food chain) and can act as an indicator species: Their diet and habitat is supported by a high biodiversity; if this biodiversity declines, so does the quality of their habitat and quantity of their food, and eventually cetaceans. So they can tell us a lot about the state of an ecosystem and are of great ecological value!

Combined with their popularity, it makes them the perfect flagship species to raise awareness about other environmental features!

How? Well, because humans want to protect them, and by doing so they indirectly protect the underlying ecosystems and the small slimy ugly species also found in these ecosystems. No matter how interesting you try to make an image of a piece of seaweed look, it won’t be received as well as a dolphin. In fact, using a flagship species such is what non-governmental organisations (NGOs) use in order to get sponsorship, public awareness or media attention to support the conservation of less charismatic species and therefore biodiversity at large.

flickr | UnsplashSo next time you see a whale or dolphin take a moment to think about why we love them so much. Think about their smiles and about how it is both the curse of being held in captivity and a blessing because of the conservation efforts made!

By Lorain Drennan, Assistant Research Officer

Are you interested in going on a trip to Tenerife to work on the Whale and Dolphin Conservation project? You can also take a look at our other marine conservation projects here.

Friday
Apr012016

Cetacean Communication: How Whales and Dolphins Use Sound To Interact With Their Environment

Water is an excellent sound conductor, making sound travel 4.5 times faster than air. Other senses are less effective underwater, making hearing essential. Cetaceans are therefore extremely dependent on their highly-developed auditory system which lets them hear, produce sound and echolocation (also called bio-sonar), all of which allows them to sense, interpret and respond to their environment. Because cetaceans rely so heavily on sound for communication and echolocation, noise pollution from human activities is a major threat to their survival.

Basic hearing is done through the ears which are very small vertical slits located just behind each eye. A dolphin’s hearing range is six times better than a human’s! Cetaceans produce three types of sound: whistles, discrete calls and clicks. They use these for communication or echolocation.

Pixabay / Joakant Communication

Communication is highly important to the survival and health of all animals as it allows them to share danger warnings, find mates, teach their offspring and share interests. Cetaceans communicate with each other verbally and non-verbally.

Verbal sounds are clicks, whistles, and groans which they use for different kinds of communication and socializing.  Baleen whales (mysticetes) such as humpbacks and blue whales have low-frequency hearing and produce a complex series of whistles and discrete calls (‘whale songs’) to communicate. These sounds can travel longer distances and are therefore also used for orientation when travelling. Male humpback whales vocalise during the mating season to either ‘flirt’ with the ladies or ward off other males.

Killer whales use whistles for close-range communication and coordination between each other. The most common vocalization of killer whales is the pulsed-call and a pod shares the same calls, a dialect. The dialects are essential for the identification and cohesion within the group. They are learned and transmitted through generations and no two pods have same dialect. Dolphins use unique signature whistle” to identify and call each other. Mothers can imprint a signature whistle upon their calves so they recognise her. Sound is also used to communicate during group hunting, and a pod keeps together by keeping within hearing limits of one another.

Pixabay / djmboxtermanNon-verbal behaviours can be tail-slapping and breaching which produce a sound heard for hundreds of meters below the surface. Tail-slapping for example is used to scare schools of fish together when hunting, while breaching is an alert of an abundant source of food nearby.

Echolocation

Echolocation is a technique used to determine the size, shape, structure, composition, speed and direction of an object; detailed information about the animal’s environment. Bats and other marine mammals also use it, but only cetacean echolocation is sensitive enough to detect the difference between a ping-pong and a golf ball! Humans have copied a cetacean’s echolocation properties in sonar equipment used in submarines and in the mid-1980s the US Navy even trained dolphins to search for mines using echolocation.

wikipedia

Toothed whales (odontocetes) such as killer whales and bottle-nose dolphins produce create high-frequency sounds, a series of short and intense low-frequency pulses (usually clicks) of ultra-sonic sound. These are produced in a complex chamber in the airway atop the head and passed through the melon (fat-filled organ in the forehead) that focuses the sound waves into a beam (just like a magnifying glass focuses a beam of light) which speeds through the water and bounces off surrounding objects. Some of the sound reflects and returns in the form of an echo.

The 80-100 cone-shaped teeth act as antennae to focus incoming sound to the fat-filled cavities of the lower jaw bone (pan bone) which acts like a human’s outer ear. The vibrations are then conducted to the middle ear, to the inner ear bones (hammer, anvil and stirrup) and to the brain. The auditory nerve is three times larger than a human’s and is able to transmit the complex echolocation and vocalization signals. And convert the vibrations into electrical impulses. The size, shape, speed, direction, distance and texture of any object is decoded into an acoustical picture, allowing them to stalk and catch prey even in total darkness. A cetacean’s echolocation is closely integrated with their sight, making it easy to relate things they hear and see.

By Lorain Drennan, Assistant Research Officer

Are you interested in going on a trip to Tenerife to work on the Whale and Dolphin Conservation project? You can also take a look at our other marine conservation projects here.

Monday
Mar212016

Cooperative Feeding in Dolphins 

Here in the Frontier Tenerife house, as on most projects, we share the cooking duties. One or two people will prepare and cook the food for everyone, and we all eat together. I guess you could call this a kind of cooperative feeding! But March is not volunteer awareness month, so let’s talk about cooperative feeding in dolphins!

Animals which appear to show a high level of intelligence, such as primates and cetaceans, also appear capable of a range of cooperative behaviours including a variety of feeding techniques.[1] Dolphins face the challenge of finding and capturing small prey in oceans, and one solution is group hunting. It requires a group to act together to the benefit of all, and only works if there is no cheating![2]  

A number of dolphin species have been observed feeding cooperatively in a variety of ways around the world, including common dolphins (Delphinus delphis), dusky dolphins (Lagenorhynchus obscurus), and spinner dolphins (Stenella longirostris) working together to create dense patches of prey to feed on.[2, 3, 4]

One of the resident species here in Tenerife, the bottlenose dolphin (Tursiops truncatus), is a species which displays a very catholic diet and a range of hunting techniques. In the Bahamas, they have been observed feeding cooperatively by swimming quickly in a wide line, with the end dolphins swimming faster to form a circle before diving in synchrony. This action herds fish towards the grassy sea bed where they are more easily captured.[5]

Another cool method of feeding shown by bottlenose dolphins in South Carolina and Georgia is ‘strand-feeding’ where dolphins swim quickly in unison, driving fish ahead of them onto mud banks where they simultaneously strand themselves to pick off the fish.[6] While a number of dolphin species show cooperative feeding, bottlenose dolphins also display a very unusual technique; cooperative feeding with role specialization. In other words, individual dolphins within the group have a specific role to play within the hunting event. In Florida groups of bottlenose dolphins work together to herd fish, with one animal acting as the ‘driver’, herding fish towards the ‘barrier’ dolphins. This herding causes the fish to leap into the air to try and escape… right in to the waiting mouths of the dolphins! This behaviour was observed many times, with the ‘driver’ dolphin in each group always being the same animal, therefore showing role specialization. [7]

One interesting example of cooperative feeding, is dolphins cooperating with fishermen with both humans and dolphins benefitting from improved prey capture. In southern Brazil, a small artisanal fishing community cooperatively catches mullet with bottlenose dolphins through a series of ritualized behaviours. The fishermen wait in a line while the dolphins drive the fish towards them from the deeper water. The fishermen have learned to watch for the nodding head movements of the dolphins, allowing them to cast their nets at exactly the right moment and in the perfect location, disorienting the fish and allowing the dolphins to more easily catch stray individuals. It is only a small subset of the resident population of bottlenose dolphins in this area which display this behaviour which is learned, and passed on from mother to calf.[8, 9] A similar cooperative technique occurs in Myanmar, this time with Irrawaddy dolphins (Orcaella brevirostris), rather than bottlenose. The fishermen attract the dolphins to their canoes with noises and splashes and wait to see if the dolphins will ‘agree’ to fish with them. If so, the dolphins will drive the fish towards the fishermen by swimming in tighter and tighter circles. Catches for the fishermen were always greater during cooperative feeding than non-cooperative, and the fact that the fishery has existed for at least 130 years suggests the dolphins must do pretty well out of it too![10]

This is barely scratching the surface of another fascinating aspect of cetacean biology, and hints at intelligence and behaviours that we are yet to fully understand in these amazing animals. Just another reason to love dolphins!

By Bryony Manly - Assistant Research Officer

Are you interested in going on a trip to Tenerife to work on the Whale and Dolphin Conservation project? You can also take a look at our other marine conservation projects here.