Bergen Museum hosts international cephalopod experts
An enthusiastic group of top international cephalopod experts met in Bergen in early September to analyse and study the large cephalopod collection gathered during the two-month MAR-ECO Project cruise aboard the Norwegian RV, G.O.Sars, summer 2004 to the waters over the northern mid-Atlantic Ridge. The collection is one of the largest deep water cephalopod collections in the world.
The scientists included in alphabetical order Martin Collins (UK), Henk-Jan Hoving (Netherlands), Volker Miske (Germany), Uwe Piatkowski (Germany), Michael Vecchione (USA), and Richard Young (USA). The goal of the workshop was to try to finish documenting and identifying the cephalopod material collected during the G.O.Sars cruise (over 1200 specimens).
The workshop was held at Bergen Museum, University of Bergen. Endre Willassen, the curator for the museum's invertebrate collection, was the host.
During the two-month G.O.Sars cruise researchers collected around 80 000 organisms. Of these 60 000 were fish. Museum curator Ingvar Byrkjedal reports that a number of international taxonomy specialists have visited Bergen Museum these past two years to work with local specialists to document and identify the material. In addition material has been sent to experts abroad. In just two short years, MAR-ECO researchers and associates have identified an amazing 98% of the fish collection. A total of 56 000 fish from 354 different taxa (family/genus/species) have been recorded!
|The cephalopod collection has been more difficult to catalogue. Uwe Piatkowski explains that cephalopods have soft bodies that are easily damaged in most trawling methods. However, the beaks or mouth parts are made of harder material and are unique to each species and thus can be used to help identify specimens. |
In addition to the more routine identifying and cataloguing work, most of the visiting researchers have particular questions they hope to be able to use the sample material to address.
Henk-Jan Hoving is a PhD student at the University of Groningen in the Netherlands. He is studying growth and reproduction in deep-sea squids. He uses a unique structure, the statolith, to determine the age of the organisms he studies.
Like the otolith in fish, squids have a calcareous structure, the statolith, which is used for balance and orientation.
The otolith in fish has been found to be a valuable tool for determining the age of a fish. This is because some organisms continually lay down new calcareous material as they grow. Because of differences in environmental conditions such as temperature, water quality etc, these new layers can be seen as concentric rings or zones, like the rings of a tree. The zones can be counted to determine age.
Hoving is currently particularly interested in samples of a small squid, Heteroteuthis dispar. This squid may win the prize for having the largest spermatophore per body weight among squid! The males produce a sperm package, the spermatophore, which they transfer to the females before they are fully sezually mature. The females carry the spermatophore around until the time is most optimal for fertilisation.
The amazing thing is that this spermatophore is around three percent of the females' body weight. This can be seen as a true adaptation for the deep-sea where it can be difficult to find a mate. During his work at Bergen Museum, Hoving was trying to determine the morphological structures that make such an unusual reproductive process possible.
Volker Miske is a PhD student studying systematics, distribution and biology of deep-water cephalopods at the Ernst Moritz Arndt University of Greifswald in Germany. Systematics is an important tool in Biology, explains Miske; knowing what species you have is fundamental to studying its biology.
From early childhood Miske has dreamed of becoming a marine biologist. It may have been that viewing Cousteau's "Night of the Squids" in his "Secrets of the Sea" series was one of the key experiences which determined the course Miske would later follow.
After immersing himself in as many biology related courses as possible and doing parallel Diploma exams at the universities Greifswald and Rostock, Miske found himself a challenging thesis project. The project was complicated by depending on material from a museum collection that although large, was considered unusable because the labels had lost their lettering.
Miske enlisted the help of a crime specialist who was able to use a special UV technique to render the labels legible again! The organisms could again be identified and related to the geographic location where they had been collected.
This was only the first hurdle Miske had to overcome. He was interested in a particular group of deep-sea squid that live between 1000 and 3000 m deep, Bathyteuthis Abyssicola.
It was believed that there was only one described species of this family in the Atlantic (another has bee described in the Pacific), but Miske's work with the recovered museum collection demonstrated that some of the specimens display significant morphological differences to the first species.
The MAR-ECO G.O.Sars cruise collected material containing many specimens with the same characters. By analyzing and comparing their morphological characteristics and by also conducting DNA tests on tissue samples, Miske hopes to clarify what these specimens are; one spieces or two, or maybe even more!
Miske's work is a good example of the challenges that face deep-sea researchers according to Mike Vecchione. Director of NOAA's Systematics Laboratory located in the Smithsonian Natural History Museum in Washington, Vecchione is well placed to know about deep sea mysteries. Through his work, he fields questions from around the world about finds of unusual cephalopods.
In a guest lecture at the Department of Biology at the University of Bergen, Vecchione spoke about a "mystery" squid that has been sighted several times in the last decade in deep waters in many of the world’s oceans but has yet to be captured and identified.
"People often think that today we can just do a DNA test and get the answer, but this is not true. DNA-testing is a useful tool in the identification and documentation of whether a particular specimen is a new species or just a variation of an already identified one, but it cannot replace morphological studies and comparisons of actual specimens," explains Vecchione.
Assembling a group of experts with their collective experience and knowledge makes this comparison process much more effective.
The G.O. Sars material from the waters over the northern mid-Atlantic Ridge have yielded at least one new species thus far, Promachoteuthis sloani, and more new species are possible. It has also provided material that has helped to flesh out the descriptions of species that have previously been described.
Vecchione stresses how exciting this research is. We know so little about deep-sea organisms. Our finds and observations are limited to brief "snap-shots" of time; a trawl haul or an underwater video. Many species descriptions are based on just one or a few specimens. There is so much more out there to learn.
The findings of the G.O. Sars cruise in 2004 have encouraged other national initiatives to conduct follow-up exploration ventures to the same area.
The newest British research vessel, the RRS James Cook, will conduct a series of three summer cruises to the Charlie-Gibbs Fracture Zone and the American RV Bigelow will also head to the same area in the summer of 2007. The cephalopod experts are keen to get more cephalopod material to study.