King Crustacean
A King Crustacean (Photo: Thomas P. Peschak / SOSF)
A King Crustacean (Photo: Thomas P. Peschak / SOSF)
Video: The National Lobster Hatchery in Cornwall is pioneering new methods of rearing juvenile lobsters to restock natural populations.
Video: Thomas Peschak talks about the challenges of photographing a rather unusual subject - the Lobster.
Download the PDF of the BBC Wildlife Summer 2009 Article
Ocean Acidification - Dissolving Lobsters
They may have scrambled over the hurdles of nature for the past 400 million years, and restocking programs together with protected areas may be giving them a fighting chance against industrialized fishing, but even the five-legged lobster has its limits. Rising acidity in the ocean water caused by CO2 emissions threatens to lower ocean calcium carbonate levels, the very building blocks of a lobster’s shell. The acidity also takes its toll on sperm and eggs. For a compulsive shedder that practices external fertilization - this is bad news. If the world is squeamish about boiled lobsters surely dissolved is not the way to go.
Read more about ocean acidification here.
Lobster History
The ancestor of the lobster was a shrimp-like animal; it was only by the Jurassic era that the clawed lobsters, which perhaps flossed the teeth of dinosaurs, appeared looking like those chilled on seafood buffets today. The dark depths of the Tethys Sea provided ideal conditions for lobsters to diversify, and they evolved into at least 53 species that colonized the world’s oceans.
Though they survived mass extinctions the clawed lobster is not indestructible, and their sortie into shallower waters saw a long-term decline in numbers. Before their current nemesis, the lobsterman, started cramping their style with lobster pots, lobsters had to contend with another species. Transformed from their very own body structure into a smarter, faster, and more adaptable crustacean, the crabs became the lobster’s toughest competitor. Today, only 12 species of clawed lobster survive near shore.
The European lobster, Homarus gammarus, ranges along the Western seaboard of Europe from Norway down to the Azores and Morocco, including the North-Western Black Sea and the Mediterranean. Overall, four distinct genetic populations of this species have been identified in these areas. The European lobster has a nearly identical, yet slightly larger, twin in the American lobster, which inhabits the seas off the North American east coast.
Cool Lobster Facts
· Lobsters can live to 100 years old
· Lobsters are arthropods - the same group as insects
· Lobster eyes are so geometrically exact that they have formed the blueprint of a new X-ray vision space telescope
· Lobsters are born with the same size claws but these develop into two different specialized feeding instruments
· Beneath a lobster’s shell is a jelly-soft body
· Lobsters shed every rigid body part including their stomach lining
· With each shed they can grow as much as 50%
· Lobsters fight playing a game of claw lock
· Lobster love has little to do with sight - it is all about smell
· Mating occurs face to face
· Lobsters are sometimes cannibals
Lobster Conservation
In the late 1980s the numbers of one of Cornwall’s most famous inhabitants, the humble lobster, started declining. To the small fishing communities scattered around the Cornish coastline lobster fishing is a traditional way of life and has been for hundreds of years. Most of these ports now rely on shellfish.
Lobsters are as much a part of Cornish heritage as pasties and cream teas. They are so important that their decline triggered Cornwall sea fisheries to bring in measures to safeguard the stocks. In 1994 the minimum size that could be kept was raised to 90mm, a measurement larger than the European’s, and the fishery was closed for egg bearing lobsters and crayfish.
Since then landings of lobsters across the UK have risen steadily and stocks appear to be relatively stable. In 2005 it was worth an estimated 8 million pounds to the Cornish economy.
Elsewhere, in Norway for example, warning signs of a lobster population crash were ignored and the European’s love affair with lobsters ended with the bitter closure its Norwegian fishery. Some 20 years later the stock has still not recovered.
The National Lobster Hatchery
As an additional safeguard to conserve the lobster stocks in Cornwall and the Isles of Scilly a hatchery was proposed and in 2000 the National Lobsters Hatchery was born. The National Lobster Hatchery, located in the small Cornish fishing village of Padstow, is going a long way to ensure that the supply of lobsters along the coast and off the isles continues to increase in the face of an ever-hungry crustacean crunching public. Video: The National Lobster Hatchery in Cornwall is pioneering new methods of rearing juvenile lobsters to restock natural populations.
Dominic Boothroyd, the general manager of the National Lobster Hatchery, is keen to encourage the fishing community to adopt a ‘farming’ rather than a ‘hunter gatherer’ outlook. Involvement in the project by local fishermen is key to successfully restocking these waters. The whole process starts and ends with them. Escaping the cooking pot, egg laden or “berried” females are donated to the Hatchery by fishermen - from there, Dominic and his team take over.
In the wild one in 20,000 of lobster eggs survive to reach market size. Thanks to the Hatchery the chances that most of these lobster babies will make it to maturity are high, up to 80% are expected to survive.
Lobster Life at the NLH
Once at the hatchery the big females are kept in tanks until they “spend” or shed their eggs – they can have as many as 12,000 eggs. Lobsters mate face to face, and the female carries her mate's sperm on her abdomen until she releases the eggs. The sperm is transferred from the male via ducts situated at the base of the last pair of walking legs, to the sperm sack on the female. Spawning usually occurs in the summer when the female squirts her eggs underneath the tail and externally fertilizes them. The eggs then lay in a big pool in the tail of the animal and after a few minutes they are “gelled” in place.” She carries the eggs underneath her abdomen for 9-12 months, during which time she is described as “berried”.
The larvae usually hatch from the eggs at night in batches of 500 and the following morning they are collected by hatchery staff and transferred to special rearing tanks. Inside the tanks they feed on plankton as they would in the wild, but unlike life in the sea where they float at the mercy of the ocean currents these little lobsters don’t end up as fish food.
Over the 5-10 weeks that follow they go through four stages of development. As they grow they moult, or shed their hard outer skeleton, leaving their body’s soft tissues exposed. Newly moulted individuals in the wild are extremely vulnerable to predation until their new exoskeleton has hardened to protect them. During each moult, lobsters typically increase in weight by about 50%!
At about two weeks old, when they are moulting for the third time, they start to look more like their parents, but behave more like aggressive teenagers with a cannibalistic tendency. Separation into individual rearing cells at this point becomes crucial.
Finally after three long months of care the lobsters are tough enough to fend for themselves in the coastal waters. By the time of their release the lobsters are able to swim forwards in search of a good place to hide, like gravel or course sand. While fishing for their larger siblings, the fishermen release the hatchery-reared juveniles, and once this new generation reach regulation size they may find themselves back in the trap, but the lucky few live to reach 100 years old.
For part of its life cycle the lobster leads a very secret life. Unlike its American cousin very little is known about the early benthic, or bottom dwelling, stages of the European lobster. Lobster babies or larvae, like these grown at the Hatchery, have never been seen in the wild, and the Hatchery is working to unravel the mystery.
As well as safeguarding the livelihoods of members of the Fishing Industry a healthy stock of lobsters reaches into the heart of the tourism, retail and restaurants of Padstow and the surrounding areas.
The NLH educates at every level, from pre school groups to postgraduate students. It is one of the very few marine biology labs in the world that is open to visitors, and each year some 30000 people walk through its doors.
In addition to seeing first hand the progression of a lobster from egg to adult, visitors can learn about the wider marine environment and why it should be protected. It offers the perfect opportunity to enthuse kids with passion for our seas from an early age. At the Save Our Seas Foundation we believe is vital to teach the children of today to be custodians of our marine world tomorrow. We need to give back to our seas now and the NLH shows that it is possible to continue to enjoy all our oceans have to offer while maintaining a health balance.
Video: Thomas Peschak talks about the challenges of photographing a rather unusual subject - the Lobster.
Download the PDF of the BBC Wildlife Summer 2009 Article
Ocean Acidification - Dissolving Lobsters
They may have scrambled over the hurdles of nature for the past 400 million years, and restocking programs together with protected areas may be giving them a fighting chance against industrialized fishing, but even the five-legged lobster has its limits. Rising acidity in the ocean water caused by CO2 emissions threatens to lower ocean calcium carbonate levels, the very building blocks of a lobster’s shell. The acidity also takes its toll on sperm and eggs. For a compulsive shedder that practices external fertilization - this is bad news. If the world is squeamish about boiled lobsters surely dissolved is not the way to go.
Read more about ocean acidification here.
Lobster History
The ancestor of the lobster was a shrimp-like animal; it was only by the Jurassic era that the clawed lobsters, which perhaps flossed the teeth of dinosaurs, appeared looking like those chilled on seafood buffets today. The dark depths of the Tethys Sea provided ideal conditions for lobsters to diversify, and they evolved into at least 53 species that colonized the world’s oceans.
Though they survived mass extinctions the clawed lobster is not indestructible, and their sortie into shallower waters saw a long-term decline in numbers. Before their current nemesis, the lobsterman, started cramping their style with lobster pots, lobsters had to contend with another species. Transformed from their very own body structure into a smarter, faster, and more adaptable crustacean, the crabs became the lobster’s toughest competitor. Today, only 12 species of clawed lobster survive near shore.
The European lobster, Homarus gammarus, ranges along the Western seaboard of Europe from Norway down to the Azores and Morocco, including the North-Western Black Sea and the Mediterranean. Overall, four distinct genetic populations of this species have been identified in these areas. The European lobster has a nearly identical, yet slightly larger, twin in the American lobster, which inhabits the seas off the North American east coast.
Cool Lobster Facts
· Lobsters can live to 100 years old
· Lobsters are arthropods - the same group as insects
· Lobster eyes are so geometrically exact that they have formed the blueprint of a new X-ray vision space telescope
· Lobsters are born with the same size claws but these develop into two different specialized feeding instruments
· Beneath a lobster’s shell is a jelly-soft body
· Lobsters shed every rigid body part including their stomach lining
· With each shed they can grow as much as 50%
· Lobsters fight playing a game of claw lock
· Lobster love has little to do with sight - it is all about smell
· Mating occurs face to face
· Lobsters are sometimes cannibals
Lobster Conservation
In the late 1980s the numbers of one of Cornwall’s most famous inhabitants, the humble lobster, started declining. To the small fishing communities scattered around the Cornish coastline lobster fishing is a traditional way of life and has been for hundreds of years. Most of these ports now rely on shellfish.
Lobsters are as much a part of Cornish heritage as pasties and cream teas. They are so important that their decline triggered Cornwall sea fisheries to bring in measures to safeguard the stocks. In 1994 the minimum size that could be kept was raised to 90mm, a measurement larger than the European’s, and the fishery was closed for egg bearing lobsters and crayfish.
Since then landings of lobsters across the UK have risen steadily and stocks appear to be relatively stable. In 2005 it was worth an estimated 8 million pounds to the Cornish economy.
Elsewhere, in Norway for example, warning signs of a lobster population crash were ignored and the European’s love affair with lobsters ended with the bitter closure its Norwegian fishery. Some 20 years later the stock has still not recovered.
The National Lobster Hatchery
As an additional safeguard to conserve the lobster stocks in Cornwall and the Isles of Scilly a hatchery was proposed and in 2000 the National Lobsters Hatchery was born. The National Lobster Hatchery, located in the small Cornish fishing village of Padstow, is going a long way to ensure that the supply of lobsters along the coast and off the isles continues to increase in the face of an ever-hungry crustacean crunching public. Video: The National Lobster Hatchery in Cornwall is pioneering new methods of rearing juvenile lobsters to restock natural populations.
Dominic Boothroyd, the general manager of the National Lobster Hatchery, is keen to encourage the fishing community to adopt a ‘farming’ rather than a ‘hunter gatherer’ outlook. Involvement in the project by local fishermen is key to successfully restocking these waters. The whole process starts and ends with them. Escaping the cooking pot, egg laden or “berried” females are donated to the Hatchery by fishermen - from there, Dominic and his team take over.
In the wild one in 20,000 of lobster eggs survive to reach market size. Thanks to the Hatchery the chances that most of these lobster babies will make it to maturity are high, up to 80% are expected to survive.
Lobster Life at the NLH
Once at the hatchery the big females are kept in tanks until they “spend” or shed their eggs – they can have as many as 12,000 eggs. Lobsters mate face to face, and the female carries her mate's sperm on her abdomen until she releases the eggs. The sperm is transferred from the male via ducts situated at the base of the last pair of walking legs, to the sperm sack on the female. Spawning usually occurs in the summer when the female squirts her eggs underneath the tail and externally fertilizes them. The eggs then lay in a big pool in the tail of the animal and after a few minutes they are “gelled” in place.” She carries the eggs underneath her abdomen for 9-12 months, during which time she is described as “berried”.
The larvae usually hatch from the eggs at night in batches of 500 and the following morning they are collected by hatchery staff and transferred to special rearing tanks. Inside the tanks they feed on plankton as they would in the wild, but unlike life in the sea where they float at the mercy of the ocean currents these little lobsters don’t end up as fish food.
Over the 5-10 weeks that follow they go through four stages of development. As they grow they moult, or shed their hard outer skeleton, leaving their body’s soft tissues exposed. Newly moulted individuals in the wild are extremely vulnerable to predation until their new exoskeleton has hardened to protect them. During each moult, lobsters typically increase in weight by about 50%!
At about two weeks old, when they are moulting for the third time, they start to look more like their parents, but behave more like aggressive teenagers with a cannibalistic tendency. Separation into individual rearing cells at this point becomes crucial.
Finally after three long months of care the lobsters are tough enough to fend for themselves in the coastal waters. By the time of their release the lobsters are able to swim forwards in search of a good place to hide, like gravel or course sand. While fishing for their larger siblings, the fishermen release the hatchery-reared juveniles, and once this new generation reach regulation size they may find themselves back in the trap, but the lucky few live to reach 100 years old.
For part of its life cycle the lobster leads a very secret life. Unlike its American cousin very little is known about the early benthic, or bottom dwelling, stages of the European lobster. Lobster babies or larvae, like these grown at the Hatchery, have never been seen in the wild, and the Hatchery is working to unravel the mystery.
As well as safeguarding the livelihoods of members of the Fishing Industry a healthy stock of lobsters reaches into the heart of the tourism, retail and restaurants of Padstow and the surrounding areas.
The NLH educates at every level, from pre school groups to postgraduate students. It is one of the very few marine biology labs in the world that is open to visitors, and each year some 30000 people walk through its doors.
In addition to seeing first hand the progression of a lobster from egg to adult, visitors can learn about the wider marine environment and why it should be protected. It offers the perfect opportunity to enthuse kids with passion for our seas from an early age. At the Save Our Seas Foundation we believe is vital to teach the children of today to be custodians of our marine world tomorrow. We need to give back to our seas now and the NLH shows that it is possible to continue to enjoy all our oceans have to offer while maintaining a health balance.