Andy Horton LARGE LOBSTER
We have a large 4kg (9 lb) European Lobster, Homarus gammarus. And we want to keep it alive in a healthy condition for study and filming. Len Nevell has kept smaller Lobsters for three years before, but keeping the larger ones presents a more difficult proposition because of space, feeding and providing fresh sea water. I don't envisage a self contained circulating system to be adequate.
This opportunity does not come up all that often because Lobsters of this size are not caught nowadays in the English Channel very often. I do not think I would take up the proposition on my own, but we have access to a fresh seawater system. Details to be established.
A has anybody tried this before please and can pass on any tips? I know Public Aquaria have kept large lobsters but from what I gather their life span in captivity has only been a few months. They need to be kept in a tank/contained on their own. The one example I have known and they kept the Lobster in a large community aquarium.
Cheers
Andy Horton.
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George Brown Is it male or female? Why do you have to keep it out of its natural environment? We know quite alot about lobsters.
Andy Horton Don't have to. We could eat it. It could be filmed and returned. It is not my chosen field of study. Len has reared them from larvae to adult but I think then the problem occurs when the larger ones moult. Needs fresh sea water on a very regular basis. No point stashing them in a big tank with the sharks as it gets lost and it cannot be seen clearly. I agreed in principle if the right conditions could be supplied. This means fresh pumped in seawater on a regular basis. It could be returned to one of the new Conservation Zones when they are implemented? We might never see a large one again! Its a male.
Andy Horton Do you know your Lobsters?
http://www.lobsterscience.ca/faq/
Is a lobster that contains a reduced amount of meat within the shell pre or post molt?
Answer:
It is post-molt. This occurs because after a lobster molts there is a larger quantity of water inside them. When they are cooked this water is evaporated and therefore makes the meat appear shrivelled up.
You explained how the lobster molts, but I am puzzled how they would be able to get their claws out of their old shells which can be extremely thick compared to their back side.
Answer:
As lobsters get closer to the molt, they dehydrate themselves and a proportion of their blood is withdrawn from the appendages, including the claws, to make them smaller. It is reported that a 30 to 60% loss of tissue mass occurs in the claws, facilitating the withdrawal of the large portion of the claw through the smaller upper leg portion through which it must pass.
Andy Horton American Lobsters are larger: http://articles.nydailynews.com/2012-02-24/news/31097229_1_lobster-rocky-aquarium-director
Mel Broadhurst Hi, yes I would certainly keep it in a tank by itself. Also if you could put in some differing types of substrate such as cobbles, mixed sands and a cave. They like a mixture (sand for looking for prey, cobbles and bedrock for moving around), and particularly like to dwell within crevices. Not too much lighting either... there are some other things, I will try and remember. I used to look after some H. gammarus so will go through my old notebooks (joy!!). Hope this helps.
Francesca Blampied put it back in the Sea.
Andy Horton I am not in charge of this project or party to the details, except that it will be kept in an old lobster storage pen of thousands of gallons of seawater that is renewed on the tide when the conditions are suitable. It has a a rival for the (non-berried) female but it is not so handsome, and slightly smaller. Not much smaller though and the female is longer but because of its smaller claws probably not as heavy. I am glad it is not my responsibility.
Andy Horton I would be interested to know what prompts the moult in the Lobster. It is hormones on the Shore Crab and it seems to be determined at regular time intervals and appears seasonal (but I don't think it is the amount of light or sea temperature). In large Lobsters it may be determined by dietary intake ??? Withe smaller ones it may be regular intervals ??
Andy Horton How long can a Lobster live for? Homarus gammarus. The theory rather than actual examples. Can they live for 25, 50, 100, 250, 500+ years (in theory)?
Andy Horton http://science.howstuffworks.com/environmental/life/zoology/marine-life/400-pound-lobster1.htm
Huan Tan Negligible senescence is the term used to describe the way that they age, in other words they don't deteriorate like humans do with increasing age.
David Kipling http://longevity-science.org/BioEssays-1993.pdf
David Kipling They still have an extrinsic mortality rate (ie non age-dependent) so they still die. The key thing is that their reproductive ability increases with age - it scales with body mass. This is why leaving big lobsters behind is key, they produce far more offspring per lobster than smaller ones. The lack of decrease in reproductive ability is one of the reasons they are termed as having negligible senescence.