Whales in the news.

There are several species of whale that live and migrate through the waters of the Norwegian coast, they can most often be viewed from boats at northern locations along the coast. It is not however very common to spot these beautiful creatures from Bergen and especially not from the the fish market at the city centre harbour....but a few weeks ago to everyones suprise a pod of around 50 pilot whales decided to visit. You can see the pictures and a report in the local newspaper here....

http://www.bt.no/nyheter/lokalt/Hvalene-inntok-Bergen-sentrum-2538667.html

The whale team and the work here at the whale hall has also been in the news recently and you can see the pictures and hear the report from the Bergens Tidende here....

http://www.bt.no/nyheter/lokalt/Hvalvask-og-annet-forefallende-arbeid-2538070.html

and the report from Aftenposten here......

http://www.aftenposten.no/nyheter/iriks/article4193650.ece

The Whale Skeletons Reveal a Little of Their History

As we clean and repair the whale skeletons we are increasingly discovering clues to their past, both as living beings (growth, age, pathology) and as specimens destined for museum exhibition.

Marielle has been examining the skeletons, bone by individual bone, for cut marks which can give her clues as to how the dead whales were defleshed and prepared so that the skeletons could be extracted, cleaned and re-articulated ready to hang in the whale hall.

All of the whale skeletons in the hall that she has examined so far have shown extensive cut marks on many of the bones. By mapping these marks and researching historical documents she has been able to build up a picture of how the skeletons were prepared.

Although it is not known whether the whales we have here were acquired by the museum through beachings or brought into whaling stations along the Norwegian coast Marielle has found that the cutting marks illustrate that the whales were defleshed by hand. The vast quantities of blubber were removed using flensing knives designed for this purpose.

An example of a flensing knife, specifically designed to remove whale blubber.

After being defleshed Marielle thinks the the skeletons may have been cut up into manageable pieces to allow them to be more easily moved around. She has found that many of the largest bones such as the skulls have been cut into two pieces, presumably so that they could be brought up into the musuem before being fixed back together.

The dissected out bones, once defleshed would then have either been put into a bath of degreasing agent to remove the remaining tissue and grease, left in shallow water or buried in soil to allow microbial cleaning. Marielle is continuing her investigations and hopes to find more evidence from the skeletons which will allow her to work out exactly which of these maceration processes was used. We'll keep you updated!

The Scaffolding Move

We've made a little time lapse video of the scaffolding coming down from around the completed skeletons and the new structure going up. Just click on the link below......

It's a Big Day in the Whale Hall

Beginning today and over the course of this week the scaffolding will be dismantled and taken down as the cleaning, repairing, conserving, restoring and stabilising of the whales in the first half of the whale hall is complete. This is an important day for everyone on the whale team as we have worked really hard over the last year on these huge skeletons and it marks the progress we have made on the project.
Scaffolding will now be set up around the whales occupying the second half of the hall - these are the smaller Minke whales and a Fin whale. In addition the tail of the Blue whale and the skull of the first Fin whale will be now be accessible from the new scaffolding.
As the scaffolding comes down today we can see the newly cleaned skeletons from the floor and it looks great. We are really pleased with the work so far and we can't wait to get started on the next skeletons.

The Blue Whale

We have started on work on the largest of the whale skeletons housed in the hall - the huge Blue whale. The process of cleaning, repairing and restoring process has begun on the massive skull and mandibles of this rare specimen. It is clear that over the years many repairs have been carried out on this skeleton, particularly in the region of the base of the skull and maxilla. Whereas some areas of bone have been skilfully replaced by wood there is also much plaster and paint which has been applied to various areas and is ugly and visible. Of course, there is also the layer of oil, dirt and dust that afflicts all the bones in the collection.An example of the paint, plaster, fragile bone and old repairs on the surface of the the Blue whale maxilla.
An initial test clean showed that although the wet cleaning techniques used previously would be suitable for the mandibles (lower jaws) and some areas of the skull, the thick plaster and paint layers would be harder to remove and required a different cleaning method.

Wet cleaning of the Blue whale right mandible. The results can clearly be seen.

It was decided that some of the plaster could be gently chipped off by hand and that sand blasting would be used to for the stubborn paint, dirt and oil on the under surface of the maxilla.

Although sand blasting sounds like a very harsh technique to use on old whale bone it can be modified by both the substrate used and the air pressure to be quite gentle. For these purposes a relatively low air pressure was used to ensure that only the dirt and paint and no surface bone was removed.

Carefully chipping away at the plaster on the ventral surface of the maxilla.

Using the sand blasting machine to clean the paint, plaster residue, dirt and oil from the maxilla.

The results of a sand blast cleaning a strip of the maxilla. As you can see it was very effective.

A comparison between the cleaned (left of picture) and un cleaned Blue whale skull base.

A comparison between the cleaned (left of picture) and un cleaned Blue whale maxilla.

The results of the combination of wet cleaning and sand balsting on the Blue whale skull and mandibles have been amazing - the rather dark, dirty, painted and platered bones have been transformed.

Fixing the Flippers

The Sei whale skeleton, positioned in the whale hall next to one of the large windows has sustained, over many years, degeneration of the finger bones that are situated in the flippers. The bones have cracked and split and in some places fallen away completely. This has left gaps where finger bones should be and lots of missing pieces of bone.

A picture of the left flipper before the restoration work began. The degraded fingers bones can be seen.

It was decided after discussions with the curators of the whale hall that we would repair the broken, and replace the missing bones to make the overall appearance of the flippers better. This would be carried out using special conservation techniques that could easily be reversed and removed so that the skeleton was not permanently altered. We do not want to 'trick' people into thinking that our repairs and replacements are real bone and although from a distance the flippers now look complete, when up close it is obvious which parts of the flippers are bone and which are not.

Zina undertook the task of restoring the Sei whale flippers and began by making moulds of some of the intact finger bones in order to make replica casts that could be used to replace the missing bones. She used alginate (a substance used by dentists for making moulds of peoples mouths) to make moulds of the finger bones and then Jesmonite AC100 (which is similar to plaster of paris) to make the exact casts from the rubbery alginate moulds. The bones were cast in two halves and stuck together on the flipper with more Jesmonite.

One half of a Jesmonite finger bone cast in position and ready to be completed.

Two Jesmonite bone casts secured in position on the phalanx at the bottom of the picture, ready for painting.

Once in place Zina very carefully (and cleverly) painted the Jesmonite bone casts with acrylic paint.

Two jesmonite finger bone casts in position. The cast to the right has been completed with paint, allowing it to blend in with the other bones.

The next task was to repair and fill the bones that had badly degraded. Zina did this by first protecting the broken bone surfaces by painting them with thick Paraloid B72 (the special conservation glue we've talked about before). As Paraloid is easily removed it creates an invisible reversible layer between the bone surface and the clay so that the infilling can be removed at any time. She then used moulding clay (Apoxy Sculpt) to fill in the gaps and model the missing parts of the bone. When dried the clay was painted so that it did not stand out from the other flipper elements.

Zina working on a degraded bone. The gap where part of the bone has fallen away is filled in.

Two bones with infills.

A comparison between a painted bone infilling (to the right of the picture) and an unpainted infilled bone (to the left of the picture).

As a finishing touch Zina repaired and replaced the cork between the bones. I think you'll agree the finished flipper looks great!

The finished flipper. A great improvement!

The Sei Whale Spine is Repaired.

The Sei whale skeleton has damage to three of it's thoracic vertebrae. The vertebral processes (this is the part of the bone that points upwards) of the 11th, 12th and 13th vertebrae have been damaged and broken off from the body of the vertebrae. These had been re-attached to the skeleton by screwing the loose parts of the bone onto a piece of wood sitting on the vertebral bodies below.

The wobbly wooden block holding the broken pieces of vertebrae onto the spine.

It was decided that a more stable and aesthetically pleasing solution to the broken vertebrae was required. So, Gordon set about making a new attachment for them.

First the wood block was cut into small pieces so that it could be removed from the skeleton with the vertebral processes still attached. The bones pieces were then carefully unscrewed from their wooden attachment and cleaned.

The spine after the wooden block and attached bone pieces have been removed.

Next, Gordon took a long sheet of expanded aluminium mesh and shaped it into a long prism shape so that it could be slotted along the tops of the vertebral bodies that the bone had broken away from.

The shaped metal mesh running along the spine. This will act as a scaffold to attach the loose bone pieces to.

The metal sheet was secured to the skeleton with screws into the cork that act as intervertebral discs between the vertebra.

A screw into the cork holding the metal mesh securely in place.

There was now a stable framework on which to re-attached the bone pieces to the spine. They were bolted onto the wire mesh using stainless steel bolts through the original holes that the screws in to the wood had formed, so no further damage to the bone was sustained.

Securing the bone pieces onto the metal mesh.

A re-attached vertebral process.

It looks great and the damaged area of the spine is stable and no longer wobbles around!

Follow Bergen Musuem and The Whale Project on Facebook

You can now follow all the news at Bergen Musuem via their Facebook page. With links to what's going on, exhibitions, developments and research it's full of information. You can also catch up with the Blog there too. http://www.facebook.com/pages/Bergen-Museum/363670584803

Another Rib Repair

Here is another rib repair that Gordon has carried out. This time it was a large crack that had opened up in the bone that required filling. The deep cracks were first packed with polyether foam. A layer of ground cork mixed with B-72 (a conservation glue) is then spread over the surface of the foam. This is then covered with a skin of balsa wood 'flour' (finely ground balsa wood) mixed with B-72 to complete the fill.

Rib Repairs

In addition to cleaning the skeletons we must carry out repair work where bones have broken or degraded. This helps to stabilise the skeletons and also improves the appearance of the damaged bones.

All the repairs were undertaken using methods that will last for the forseeable future but can also be reversed (undone) if necessary. This is very important as although we wish to repair and conserve the skeletons we do not want to make permenant changes to them.

Many of the skeletons have broken ribs and Gordon has been busy repairing them. He has used different techniques depending upon the type of break or damage, as no two were the same.

The ribs were disarticulated from the skeletons so that work could be carried out on them and then re-mounted when the repairs were completed.

Here is an example of one of the repairs that Gordon has carried out on a broken rib from the Right whale ....


A) This is the break in the rib that requires repairing.


B) The ends of the bone are glued together using a special conservation glue called Paraloid that can be disolved which acetone if the bone needs to be taken apart again.


C) The joint is re-inforced with a small metal pole.



D) Small pieces of soft wood are cut and shapped to fill the gap.



E) The wood is then trimmed and smoothed to match the surface of the bone. Can you see the repair..??!

Whale Washing Videos.

Here are some links to videos about the work we are doing in the Whale Hall.

Just click on the title:
Hvalrens 2010

Hvalvask

Whale Washing (English)

How old are the whales?

We know the history of the whale hall, the date the whales were collected and which species each whale is but what we don’t know is how old the whales are. Are they baby whales or grandma whales? How can we tell?

The answer is in the morphology of the bones. The vertebrate skeleton (such as a whale’s) begins as cartilage which is then ossified (replaced by bone) as the animal grows. However at the top and bottom of the bones a strip of cartilage remains, this is known as the growth plate.

This cartilaginous plate provides a growth zone in an otherwise fully ossified bone allowing bones to increase in length and size during development. The cartilage grows continually and is steadily replaced by bone until a final size has been achieved, then the remaining cartilage will stop duplicating and is ossified, permanently closing the growth plate.

By examining the whale skeletons and looking for growth plates – which will look like gaps in specific parts of the bones as the cartilage is not longer in situ – we can tell if the individual was still growing or was a fully grown adult.

After close examinations of all 8 whales in the hall we found that every one of the whales had open growth plates in one or more bone – we found them in the vertebrae, scapular, ulna, radius, and humerus. This indicates that all of the whales were still growing and although we cannot give them a specific age we know they were not fully, skeletally mature.

Unfused growth plates in caudal vertebrae. Indicated by white arrows. Sei whale.

A close up of the unfused vertebral gowth plates. Sei whale.

Growth plates at the humerus, ulna and radius. The ulnar plate is partially fused. Sei whale.

A close up of the growth plates at the elbow.

Catherine, the anatomist on the team is currently researching how we can use the growth plates that have been found to provide a more specific age for each whale. The use of ossification status has been extensively researched and utilised to estimate chronological age in many mammalian species but due to the obvious limitations in studying the skeletons of these huge, rare, aquatic animals more research, such as that being carried out here in Bergen whale hall is required to answer our questions about whale age.

A Whale Hall Update and A Surprise Discovery

We have now cleaned three of the largest whales in the collection, a Northern Right whale, a Humpback whale and a Sei whale and we are in the process of cleaning the equally massive Finn whale. There is still some work to be carried out these skeletons as we will fill in cracks found in bones, repalce missing parts of bones and re-articulate some of the ribs which were removed for cleaning.

Things are going well and we are continuing with the wet cleaning methods we have refined over the previous months. Currently we are working on the tail (caudal vertebrae) and ribs and so far, although very dirty, this skeleton does not appear to be very oily in comparison to the others.

Whilst cleaning the tail vertebrae Marielle has come across something very interesting…..

On the dorsal surface of the lateral process of the 41st vertebrae she saw something under the dirt scratched into the surface of the bones – as she rubbed away some of the dirt it become clear…

It would appear that one of the people preparing this whale skeleton has scratched his or her initials and date into the bone – a very interesting, and very old, artefact and a very special connection to the person who was last cleaning these bones over 100 years before Marielle. You never know, there may be more surprises under the dirt as we continue…