Entries in #ocean (13)

Monday
Feb122018

Are They Really  Free?

The point is, I love whales and dolphins and this piece of writing may or may not make sense to some of you...hopefully it does, and hopefully it may even get some of you thinking.

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Monday
Feb122018

Meet the striped  dolphins

Last week our team was lucky enough to add another cetacean to the list of observed species – the striped dolphin (Stenella coeruleoalba) and, as always, we would like to introduce it to everyone.

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Tuesday
Jan232018

Rubbish on the shore - not just marine life that’s being  affected

Seeing a cat strolling around the beach and sniffing on the different pieces of rubbish made us realize once again how directly animals are being affected by garbage produced by humans.

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Monday
Jun052017

The Two Species Of Pilot  Whale

The latest blog from Tenerife looks at the only two known species of Pilot Whale; Short-finned and Long-finned.

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Tuesday
Sep272016

Proof of the Problem - Cetacean Conservation 

Last week our whale and dolphin crew notcied a situation that proves why the work we are doing in Tenerife is so important for the conservation of cetaceans. Find out what happened in this blog...

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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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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
Mar142016

Spotting Fin Whales In Tenerife 

Whales and dolphins are resident in the waters around Tenerife. On almost all our boat trips we see pilot whales and bottlenose dolphins or Atlantic spotted dolphins; they are the main species we work with on the project and it’s exciting to see them whenever we go out. Some days though, are very different!

Six weeks on the island and I am still in awe every time I see cetaceans; I get excited like a child.

It’s a beautiful sight: The pilot whales mostly rest during the day and float at the surface when we find them. The dolphins are more active, whizzing around the boat, from left to right, overtaking us from the back and surfacing every few minutes.

After a weekend of “getting things done” around the house, I went out on one of the boats and whilst scanning the horizon for whales, we suddenly saw something big surfacing ahead of us, quite close. The captain had the best view, but within seconds we all saw it: Over 20 metres long, a large body, nothing even remotely like a pilot whale. A fin whale! Another boat had spotted it too and had already had a good look at it – definitely a fin whale.

There we were, staring.

They migrate between Tenerife and La Gomera during winter and spring time and are spotted around the island twice a year; this was one of those times. It was not a very busy trip and everyone moved to the front of the boat. The crew was discussing how often they had seen them. Not often. It was the first one this year. And then we saw it again! The large body appeared next to the boat, under the water surface, we followed the tail past the front of the boat and looked right. Just then, on the right side, a blow, another, much bigger whale surfaced and there they both were.

Spirits were high on the boat! The excitement blocked out everything else, but the moment we saw both whales, someone shouted “son dos, son dos!” and we all clapped between oooohs and ahhhhs. The cameraman kept saying “I am keeping the DVD!” – he had never seen one this close in the six years he had been on the job, the captain and skipper had their phones out to record it, even they don’t see this every day and with every glimpse at the whales, we celebrated (albeit reasonably quietly so as not to disturb them).

With such an incredible sighting, I went straight back on the boat for the afternoon trip as the crew and I were hoping for one thing: Another sighting of the fin whales. The first one was by accident – or chance! – this time we headed straight into the direction we had seen it. And indeed, there it was. I managed to get the shot I wanted: The blow, the body surfacing, the fin. Almost a week later, I still watch the video every day (sometimes in slow motion and including our cheers in the background) to remind myself of the moment.

The presence of the fin whales seemed to have influenced the other marine animals, everyone behaved a little differently that day: We saw very few pilot whales, although of course we didn’t look as hard either, the sea birds were all very agitated, and we had big groups of Atlantic spotted dolphins swim all around the boat and in the waves at the front of the boat. Sometimes up to 50 animals at a time! Nothing was as impressive as seeing the second largest whale though, this day is engraved in my memory.

By Claire Herbaux - Field Communications 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
Feb292016

The Effects of Microbeads On Our Oceans 

How many times a day do you brush your teeth? Or wash your hands with soap? Did you know that every time you brush your teeth you could be washing as many as 100, 000 micro beads into the water system?

Micro beads are tiny plastic particles found in many household products and cosmetics such as toothpaste and face scrubs.  Made of polyethene (a material which does not break down and biodegrade over time) they enter our natural water systems and this is where they will stay in one form or another...

So what’s so bad about micro plastics?

Not only do micro plastics build up in our water systems and ultimately the oceans, they are highly absorbent and can add further pesticides and other chemicals to the marine environment. This poses a problem for any form of life that relies on water…which is to say all life on Earth!  

Being so tiny it is frighteningly easy to imagine how micro beads can be ingested by a variety of species and can build up in the food chain.  These particles and the associated harmful chemicals can even be found in food prepared for human consumption and also in human tissue.  

Most people have heard of marine animals mistakenly eating plastic waste such as carrier bags; in the water they can look like jellyfish to unsuspecting turtles, or ingesting large volumes of plastic debris and fishing equipment which can effectively block their digestion system perhaps preventing them from feeding efficiently or rupturing their stomachs to their extreme injury and sometimes their death. Imagine then the risk of not only ingesting plastics that we can see but also millions of micro beads that are so minute we can’t!

Take for example the short-finned pilot whale, a resident species here in the waters of Tenerife which provides so much joy to many visitors and supports a thriving tourism industry. Their main food sources are cephalopods, such as squid, which in turn are filter feeders.  Filter feeders sort through the water they are swallowing and can extract tiny pelagic species such as zooplankton. If I told you micro beads are approximately the same size as many of these zooplankton organisms can you see where the problems begin?  

Filter feeders cannot filter out all of the micro beads and separate them from the zooplankton.  Later an unsuspecting pilot whale thinks he has found a tasty squid for dinner and will continue to prey on his favourite food throughout his lifetime.  After 10/20/50 years how many micro beads do you think he will have ingested? Is it good for him? As well as affecting the digestive system it is possible the build-up of these particles and chemicals could negatively affect the reproductive and nervous systems too.  

As well as losing individuals and eventually entire populations and species through deaths caused directly by plastic damage, strandings and poisoning, the build-up of micro plastics in their bodies could mean that they cannot reproduce effectively and sustain their populations or ultimately the existence of their species.

The US and Canada have now banned the use of micro beads in cosmetics and several EU countries have lobbied to impose a similar ban throughout the Union but until then what are we going to do?

By Cara Donald - Whale and Dolphin Conservation Project

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.

Tuesday
Feb232016

Top 5 Tips Against Sea Sickness

It happens, some of us feel a little queasy when we get on boats. Sometimes it’s the waves, sometimes the walking around, but there are times when it is more than our stomachs can handle. In our case, when we are on the whale watching boats, we don’t simply look out onto the sea, but take notes, look up GPS coordinates, focus on writing and walk around; it can make you feel dizzy.


The boat crew makes it part of their safety briefing: Let them know, ask for a plastic bag, DO NOT go inside or downstairs to the bathrooms – it is hard to handle when you are unwell.

It is not the best of feelings, but in order to enjoy the trips, it is worth looking into how to avoid sea sickness the next time. Look online and you will find a myriad of tips and tricks, some helpful, some not, some not applicable. Avoid going? That would mean missing out on great experiences! Lie down? See above. Buy motion sickness tablets which make you drowsy? Do I need to repeat that we want to be aware of our surroundings?

Here are the best ways to survive a boat trip and actually see the whales, take part in the project, and enjoy it.

Step 1: Have a good breakfast and also bring a snack. There is a bit of time between breakfast and the trip, so make sure you don’t go on an empty stomach.

Step 2: Sea sickness tablets. Find the kind with caffeine or ginger, and ideally one which allows for two tablets. This way, you take one before getting on, and if you feel unwell, you can take a second.

Step 3:
Listen carefully to the crew. They will remind you where and how to sit, where not to go, and they will make you feel at ease. It’s true when they say they have probably dealt with worse. After all, you have already followed steps 1 and 2, so you are ahead of those who went on not knowing.

Step 4:
Enjoy the journey! Don’t think about whether you might get sick, it won’t help. The more distracted you are – looking for whales and at the scenery for example – the less you will think about the uncomfortable truths of sea sickness. Bring a hat or sit in the shade. Having the heat of the sun burn on your head won’t make you feel any better and neither will staring at a phone, book, or anything which distracts you from looking at the horizon.

By Claire Herbaux - Field Communications 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.