16 Feb - A whale of a time!
RRS James Clark Ross Diary
Noon Position: 53° 20.8 S, 37° 43.9 W)
Distance Travelled since Grimsby: 22068.3 Nautical Miles
Air temperature @ Noon today: 6.6°C
Sea temperature @ Noon today : 4.1°C
Weather: Good, W, 7, 1006.7 mb
Having a whale of a time......
Following another two weeks at sea everyone onboard was pleased to get ashore at King Edward Point (KEP) on South Georgia this week. A logistical call to the base also provided the chance for a little R+R for the scientists onboard. We had two days with great weather so most people headed off to have a look round the base at KEP, Grytviken, Shackleton's grave or just ramble and stretch their legs. Several parties made it up Mt. Hodges which stands sentinal over Grytviken and provides fanstastic panoramic views. People also ran the gauntlet of fur seals to get round to Penguin River and see the king penguin colony there or over to Maiviken to watch the fur seal pups playing in the fresh water lakes. On Monday night we all got down for some questionable dancing laid on by funkmeister DJ Howey in the most notorious night club of the South Atlantic, the KEP boatshed! Complete with sound system and flashing lights it was quite a remarkable night!
Below are a selection of photos of the sights to be seen around KEP.
Whilst at King Edward Point we picked up some very important and historic cargo. Tim and Pauline Carr's yacht, Curlew, is over 100 years old and has been their home for over 20 years in which time they have sailed all over the world. The yacht is on route to back to the UK to become an exhibit in Falmouth Maritime Museum. Curlew has become almost part of the scenery of South Georgia over the last few years but is now firmly tied down in our No 2 hold.
There are four researchers studying whales on our current cruise. Whales are at the top of the food chain and eat a variety of animals including krill. We know that krill provide the most important food source for many species of baleen whales but we do not know how whales find krill, how much krill they eat, nor how much time they spend feeding. Little is known about the foraging behaviour and movements of whales in relation to their environment and so Koen Van Waerebeek and Russell Leaper are visually searching for whales for the International Whaling Commission (IWC) while Ana irovic (Scripps Institution of Oceanography) and Debbie Salmon (BAS) are monitoring for sounds made by the whales.
The Southern Ocean and Scotia Sea are important feeding areas for a large proportion of the world’s whales and includes many populations that were severely depleted by the whaling industry including that based on South Georgia. It is estimated that the biomass (total weight) of whales is now only around 10% of what it was before whaling began. In 1994, the International Whaling Commission voted to adopt the majority of the Southern Ocean south of 40°S as a sanctuary in which all commercial whaling is prohibited. There is now a need to monitor whale populations and to understand the role that different species play in the Southern Ocean ecosystem.
The objective of the visual observations is to allow us to relate patterns of whale distribution to the other biological and oceanographic information being collected by the multidisciplinary team onboard, in particular the distribution of krill which is the main prey item for most baleen whales in the Antarctic. In addition to whales, the observers also note down any seals that they see because seals are also important predators.
Counting whales is not easy because they spend much of their lives out of sight under water and even when they come to the surface they are sometimes difficult to see, especially in rough seas because of reduced visibility. For some species a tall blow (or spout) is seen whereas with others all that appears is a small part of the animal’s back. The method used to work out how many whales there are is a statistical technique called line-transect sampling. While the ship travels along a pre-determined route of survey ‘transects’ the observers count how many whales of each species that they have seen and also work out the area of the ocean that has been surveyed. The distance at which whales can be seen varies according to the sea and weather conditions and this needs to be taken into account in the analysis. Russell and Koen have spent many happy hours perched on the monkey island at the top of the ship, searching the sea with binoculars and directly recording information about the whales seen on to a computer.
Since sailing on the 7 January the weather has been good enough to allow them to complete over 200 hours of visual observations. So far they have observed 9 different species of whales including baleen whales such as fin, sei, humpback, and minke whales which were all targets of the 20th century commercial whalers. We have also seen toothed whales, including southern bottlenose whales, sperm whales, killer whales, Peale’s and Commerson’s dolphins. Some of the whales are difficult to identify and this is particulary so for beaked whales that show little body when surfacing, resemble each other, and are amongst the least studied of the whales.
|Whale sightings until 15/2/03 after 199 hours of observations|
|Species of whale||Number of sightings||Total number of individuals|
|Southern bottlenosed whale||12||23|
The acoustics team has two primary goals:
Firstly they have deployed an Acoustic Recording Package (ARP), which is a passive, continuous acoustic recorder that drops to the bottom of the ocean and records low frequency noises. It can record baleen whale calls within an area of up to 50 km around the device. It was deployed on January 13th to the east of Elephant Island and will be able to detect calls from various baleen whales species: blues, fins, minkes, humpbacks, and southern right whales, which are known to make loud, low-frequency calls. It is approximately 2000 m down on the slope where the continental shelf drops down to the abysal plain. The advantages of this depth are little corrosion due to lack of oxygen and reduced noises from sources such as storms and waves. The area of deployment is interesting biologically and so has the potential for whale activity. The ARP will record for up to 500 days before it returns to the surface with the data it has collected for analysis.
The ARP can detect whales that are in the area and are making noises. It will be able to tell us at which times of the year whales are in the area and will add to the data recorded from 8 other ARP that are moored at various points down the Antarctic Peninsula. The results may have an important bearing on krill fishing that assumes that whales are only present in the area for short periods of time.
Secondly, Ana and Debbie are deploying ex US Navy sonobuoys from the JCR as we sail along. They were designed to listen for submarines but now can be used to listen to whales in real-time. The buoys consist of a hydrophone, a radio transmitter, a float, and a salt-water battery. They transmit for upto 8 hours and 7 miles from the JCR while the hydrophone drops to 300 m depth. After the buoys have finished working they sink. The data collected is important to help correlate the noises heard with the visual observations taken by Russel and Koen. When the data from the ARP is finally analysed, the species of whales heard can be determined from the calls heard based on the sonobuoy work. They will also give an idea of distribution of whales across the Scotia Sea. There are very few, if any, acoustic recordings of low frequency whale calls in this area so this is the first time fin, minke, southern right and blue whales have been heard here.
Below is a picture of a sonobuoy before it is thrown over the side into the water. One can see a white balloon at one end that keeps the battery and transmitter on the surface while the cardboard part contains several hundred metres of cable. The white back contains weights that makes the hydrophone sink to a predetermined depth. The hydrophone can been seen as the small object at the end of the black cable. They are normally deployed by the Navy from the back of helicopters and so are very robust!
Okay. So we have spent the last 6 weeks listening for whales and you are all asking what they sound like. Through the wonders of modern technology if you click on the links below you can hear small samples of what we have heard.....(Real Player required. If you don't have Real Player, a free version can be downloaded from the Real website.)
- Sperm whales making characteristic 'clicks': Click to listen...(51K)
- Odontocetes are non baleen whales that make 'squeaks': Click to listen...(14K)
- Southern right whales have never been recorded acoustically in this area before: Click to listen for the first time...(14K)
These sounds are sometimes difficult to hear but are easier to see when put in graphical form. Some whales make noises that are so low frequency that they cannot be heard by the human ear e.g. fin and blue whales. However these can be seen on a computer....
Above: Ana watching acoustic recordings (L) and graphical representation of Fin whale calls. Click the images to enlarge them.
A feeling of deja vu???
Well folks it's that time of year again. Yep, we have been repeating the Western Core Box for the second time this season. As I'm sure you are all aware from the previous diary entries that the Western Core Box is a area of intensly monitored ocean to the north west of South Georgia. The JCR has been performing transects over this area for the last 5 years to try and establish and observe any changes that are taking place. It is primarily looking at acoustic data gathered using echosounders in combination with some oceanographic observations. It looks at the concentrations of krill, fish and copepods in a series of grids and allows the biomass of these animals to be monitored over time.
You may remember in the dim and distant past that last October we tried a new technique for monitoring the area in a continous fashion. The problem with the Western Core Box is that one is only looking at snap shots of time and so cannot know exactly what is happening for the rest of the year in that area. It does however give good spacial coverage i.e. it covers a large area of sea and so hopefully the data will be representative of the whole space. So to solve the 'snap shot' problem we deployed a couple of moorings in October. These are buoys that are connected to heavy weights that sink to the sea bed. The buoys float in the water at 200 m below the surface with a cluster of sensors looking upwards at the water above. They give excellent coverage over time but there are only two so fail to have the spatial element of the Western Core Box. The sensors get a clear picture of the water above as there are no ropes above them to obscure the view. The buoys contains 3 sensors:
- Water Column Profiler - fancy name for 'the machine that goes ping'. It estimates the biomass of krill using sound waves of 120kHz.
- Acoustic Doppler Current Profiler - fancy name for another 'machine that goes ping'. This one measures speed and direction of the water current at different levels of the water column.
- Conductivity/Temperature/Depth (CTD) - this one does what it says on the tin ie measures conductivity of the water (equals saltiness), temperature and depth of the buoy in the water.
The sensors have been recording data for the last 4 months and now it is time to get that data back for analysis. The cunning bit of the plan is an acoustic release. This is a special couple that, when we fire a special 'ping' down to it, releases the buoy from the weights and the buoy gently floats back up to the surface to be collected by the ship. Once the data is down loaded we can then re-deploy the buoys for another few months.
This week we successfully released the buoys from the weights on the seabed and recovered them onto the ship for the data to be downloaded.
Once we have the data then we will hopefully redeploy the buoys at the same location as they were before at some stage next week.
The Back Page
JCR sinks South Georgia!!
South Georgia 1, James Clark Ross 3.
Grytviken Football Swamp
Billed as a key match in deciding the Sub Antarctic football league, this game was played out in stunning weather on the old football pitch at Grytviken. The South Georgia team, desperate to recover their form after a recent defeat to an HMS Endurance team went into the game as clear favourites. They started well using home advantage to avoid the areas of the ankle deep bog down the flanks of the pitch. The visitors were confused by the areas of rocky gravel next to the wet puddles and bog. A good early chance was missed when the JCR winger, Mark, who tried to jump up for a header only for find his shoes stuck in the deep moss and spent the next few minutes pulling them out. Minimal fitness and skill were evident for the first 5 minutes before complete exhaustion over took most of the team and the game descended into a static battle of tactical long balls.
The midfield battle ground was reminiscent of the Somme and at one stage 6 players were seen frantically trying to hack the ball out of a puddle for several minutes getting soaked in the process. Some could say that this puddle retained possession of the ball longer than either team and had an excellent first touch. A change of pace, reminiscent of Micky Quinn in his prime, allowed the big JCR front man, Mike, to finish clinically, sending the JCR team in at half time leading 1-0.
The second half started with Gerry, the JCR's giant goalkeeper almost disappearing down a hole infront of the goal mouth. The South Georgia team, lead by the dashing runs of Andy (the only man or woman on the pitch with any skill! - Ed), fought back but couldn't stop the JCR going further infront when Mike again pounced on a loose ball in the box to crash the ball home. The pitch was littered with individual battles such as that between, Dr 'dribbler' Dowling and the JCR's Croatian hardman, Ana 'right hook' irovic. Honours even in that contest. Most players were battling just to keep moving fast enough to avoid being swallowed by the swamp down the left wing! Frin, Kate and Suzy could only watch as Mark avoided their flying work boots and rattled the post and the underside of the bar as the JCR forward line again asked questions of the normally solid home defence. Worse was to follow for the landlubbers when Alex slotted home after a mazy splash through the bog and gave the exhausted JCR team some breathing space.
South Georgia's midfield dynamo grabbed a consolation with a fine run and shot that just beat Gerry 'the cat' Armour's fingertips. After half an hour of frantic running around in a bog whilst having someone kicking your ankles in steel toe capped boots was enough for anyone and there was general relief when the final whistle was blown. The docs were also relieved there were no major injuries and the defibrillator wasn't needed! Things are looking bleak at this early stage of the season for South Georgia and the pressure is mounting on player coach Dr Sue. She said after the game. "At the end of the day we are looking for a big name signing, probably a fur seal to add some bite to our defence!" The JCR team having sailed off with all three points and aching limbs now head south for a clash with Rothera Rovers!
Above: L-R: The gripping action on a dodgy pitch, both teams after the clash and the player coaches/doctors shake hands after the game. Click the images to enlarge them.
Thanks to Sue and Alex for organizing the game.
Thankyou this week: to the South Georgia Seven
Coming up next week: Stromness (oh yes!), Bird Island, buoys and maybe the bright lights of Stanley (hooray)!!!!