Sound. It travels faster and further through water than air and in an environment where light does not penetrate very deep, its is one of the most important senses for marine animals including whales, dolphins and porpoises. Cetaceans as they are also known use sound for communicating, finding food and navigating their way around the ocean. The great baleen whales such as those our little Morgan encountered in the Azores, use low frequency sound to communicate over thousands of kilometres, toothed whales and dolphins like Orca use sound to echolocate in order to find their food and their way. Clicks and whistles are also used to communicate, and for some species distinguish between individuals in other words they have names! Scientists have even shown that different populations of Orca for example have specific vocalisations and even that different groups within the same population have different dialects.
The amazing properties of sound in water have made it very useful to humans as well. Using sound we can identify objects at huge distances, we can work out what type of rock exists below the seabed, and we can find valuable deposits of oil and gas used to fuel our modern day lives.
The issue is that as humans we are increasing the amount of sound in the ocean, and this is having some terrible impacts on whales and dolphins. Strandings, where whales and dolphins beach themselves and injuries have been linked with active sonar. Hearing sensitivity can be affected, either temporarily or permanently. Calls can be masked so that individuals cannot hear them or they have to change the way they make their own calls in order to be heard – a bit like us raising our voices in a very noisy room. Sound can affect behaviour too, causing disturbance or avoidance of areas. The level of impact depends on the intensity and frequency of the sound, and also on the individual.
For the exploration of oil and gas, around the worldwide a number of countries have introduced legislation and guidance in order to try and reduce the impact of this sound on whales and dolphins. While arguments may continue about whether oil and gas exploration should continue, especially in certain sensitive areas, ultimately as long as people are going to search for such deposits something needs to be done to protect whales and dolphins as much as possible. Methods include delaying the start of a sound if whales or dolphins are close by, increasing the level of noise gradually over a period of time in order to warn animals in close vicinity, shutting down noise sources when animals come within a certain distance. All of which involve having experienced marine mammal observers, to spot whales and dolphins and to advise people about guidelines. And inevitably training is needed.
|Morgan at the Pro-MMO lectures|
This week our little Morgan joined participants on a Marine Mammal Observer (MMO) course run by Gardline Environmental Ltd., learning the guidelines set out for UK waters by the Joint Nature Conservation Committee (JNCC).
With a day of lecturers in a class room, our little Morgan learnt all about the properties of sound, the reasons human made sounds for oil and gas exploration can be so bad for whales and dolphins, and what these guidelines advise in order to reduce the impacts. Next it was off on a ferry in order to put into practice what they had learnt and to get some experience spotting and identifying whales and dolphins. What better place than the Bay of Biscay. With regular ferry’s crossing a range of habitat from shallow shelf waters, steep slopes, stretches of deep water and underwater canyons. The area covers habitat perfect for a range of dolphins and whales, and is one of the best places in Europe to see some of the most elusive whales, the beaked whales.
|Out on deck scanning for marine mammals|
With the weather a mixed bag and sea conditions ranging from choppy to completely flat calm, our little Morgan and the other candidates spent time on the ferry’s deck taking part in role plays and putting into practice the mitigation methods learnt in the class room. With wave after wave of common dolphin they even got to practice delaying operations! As the ferry crossed over the underwater canyons in the southern part of the Bay, a treat for Morgan and the other participants were two of those elusive beaked whales, this time Cuvier’s Beaked Whale, surfacing right next to the ferry!
Arriving in sunny Santander there was time to reflect on a wonderful days whale watching and to discuss all that they had practiced, before getting back onto the ferry for the return leg…. And of course the MMO exam!
|In sunny Santander with the Pro-MMO candidates|
With expert guidance and tuition all 10 candidates, and our little Morgan passed to become JNCC trained MMOs, ready to head off on survey vessels around the UK and beyond, in order to protect whales and dolphins from this particular form of underwater sound.