Amateur Plankton Nets: Capture Marine Planktonic Organisms to Watch or Photograph Swimming

Suitable specifications for an amateur marine plankton net require that the shape and mesh size are carefully considered.

Towing a net behind a boat, lowering it over the side, or simply throwing it into the sea from the shore and then dragging it in will capture marine plankton. There are standard designs for plankton nets, and mesh size determines what will be caught. Once captured, plankton can be kept alive for a short while in a vacuum flask which will stop the sea-water warming up too quickly.

Standard Design of Plankton Nets

All plankton nets are conical in shape, with mouth to length ratios of from 1:3 to 1:5. Small nets (five to eight inches in diameter and 15-20 inches long) are suitable for the amateur.

The mouth is held open by a rigid circular ring, and pulled through the water on a single line which ends in a three-piece ‘bridle’ where it attaches to the mouth-ring.

The netting is always made from ‘Nitex’ (a registered trademark). This nylon netting is treated so that the square mesh openings of known dimensions remain constant whatever you are doing with the net.

The pointy end of the net has a PVC collecting bottle (or ‘bucket’) which is easily detachable – this is where the captured animals end up.

Mesh Sizes of Plankton Nets

Smaller mesh sizes catch most things. A ‘small’ mesh of 80 microns (a micron, or micrometre is one thousandth of a millimetre) will catch larger phytoplankton and everything bigger than that. These nets tend to fill up fast!

‘Coarse’ mesh of 363 microns lets all the phytoplankton and many smaller zooplankton through – retaining only the larger animals.

For the amateur a ‘medium’ mesh size of 153 microns is best since it lets microscopic organisms through and keeps everything visible to the naked eye.

Keeping Plankton Alive to Observe Later

Planktonic plants and animals (such as copepods ) are very sensitive to temperature change and will die rapidly if the water begins to warm up. This is not a problem if they are to be observed immediately, but if the idea is to make a few hauls and the take the whole sample to a place where the living animals are to be observed and maybe photographed later, then they need to be kept at a constant temperature. Any sort of vacuum flask will do this, but for use in the field a stainless steel vacuum flask is highly recommended.

Once the captured animals have arrived at the place where they are going to be looked at they can be poured or pipetted into a small flat glass dish (Petri dish recommended) on top of a black card. Oblique lighting will help make them visible against this dark background (but will quickly cook them). A hand lens (X10) is very useful at this stage. Photographing planktonic animals is a challenge, and videoing them even more so!

World Wars and Biological Agents: Intentional Use of Biologic Agents in Warfare

Biowarfare in World War I

During World War I German forces in the United States secretly infected American livestock found for Europe with glanders and anthrax. Thousands of horses were killed, but American troops in Europe were largely unaffected. Chemical warfare was by far a larger concern than biological warfare during World War I: nitrogen mustard, phosgene and chlorine gas injured or killed hundreds of thousands of troops. In 1925, thirty-eight countries signed the Geneva Protocol prohibiting the use of biological and chemical weapons. Japan refused to sign the Geneva Protocol.

Interestingly, research and production of biological weapons was not prohibited by the Geneva Protocol.

Biowarfare in World War II

During World War II, Japan began experiments using biological agents on civilians and prisoners held in Manchuria. A bio-warfare unit, Unit 731, disguised as a water-purification plant was built outside of Harbin, Manchuria. A second unit, Unit 100, was built near Changchun. Anthrax, cholera, plague, typhoid and a number of other agents were used in field tests and resulted in the deaths of tens of thousands of people.

In one experiment, clay pots containing infected fleas and grain were dropped over areas in Manchuria and China. The grain attracted rats; the rats became infected from the fleas and dispersed to spread disease into the human population.

Unit 731

Plague bacteria, Yersinia pestis, was released by the Japanese at Chuhsien and later dropped from planes at Ninpo and Chinhua. Approximately 120 people were killed as a result of these attacks. However, in 1941 a serious plague epidemic began following release of Yersinia pestis in Suiyuan and Ninghsia provinces.

British Biowarfare Research

At the same time Allied forces were also experimenting with biological agents. The British experimented with anthrax on Gruinard Island off the coast of Scotland. A bomb was used to disseminate anthrax. Although the Island was thought to be far enough from shore for testing to be safe, an outbreak of anthrax occured in sheep and cattle on the coast of Scotland in 1943. The oubreak resulted in discontinuation of testing.

United States Biowarfare Research

The United States established a major biological weapon and defence research facility at Fort Detrick, Maryland and later developed smaller facilities in Dugway, Utah and Pine Bluff, Arkansas. A number of agents were investigated by the U.S., and in 1955, Pine Bluff began production of large quantities of Francisella tularensis, the causative agent of tularaemia.

Canada Biowarfare Research

Canada was also involved in research into the use of biological agents. Canada participated with the U.S. and Britain allowing field studies in remote areas of Canada.

Soviet Union Biowarfare Research

Meanwhile, the Soviet Union had been performing its own experiments with biological agents. Soviet research was directed toward plague, Marburg virus, smallpox and anthrax. The Soviets produced huge quantities of biological agents that could be loaded into missiles for deployment.

Biowarfare: Infectious Agents and Toxins in Warfare

Biological Agents

Biological agents are self-replicating living organisms or toxins produced by organisms that can be used to injure or kill humans, animals or crops. Humans, animals and plants share the earth with microorganisms: bacteria, viruses, fungi and parasites.

Among the multitude of microorganisms that inhabit the earth, most are not harmful to humans (non-pathogens), and in many cases protect us from microorganisms capable of producing disease (pathogens). However, there are hundreds of pathogens that are capable of causing disease. Some of these have been exploited for use as weapons in warfare, terrorism and crime.

Centuries before microorganisms were discovered and recognized as potential disease agents, humans used them in attacks, or as a defence, against other humans.

The History of Biowarfare


As early as the 6th century B.C. biological agents were used to poison the wells of enemies: in Mesopotamia Assyrians used rye ergot containing mycotoxins (toxins produced by a fungus) from the fungus Claviceps purpurea to poison the wells of their enemies, and hellebore (skunk cabbage), a poisonous plant, was used by the Greeks to poison the water supply during the siege of the city of Krissa.


In 1346 the Tartar army used catapults to hurl plague-ridden corpses over the walls of the city of Kaffa, a port on the Black Sea, forcing the inhabitants to surrender. And in 1422 the plague-ridden corpses of soldiers and cartloads of excrement were hurled into enemy troops at the battle of Carolstein. The same strategy was also used by Russian troops in 1710 during a war with Sweden: corpses of plague victims were hurled over the walls of the city Reval.

At the time, the causes of death were unknown, but the ability for mysterious and often fatal diseases to spread to others was certainly recognized. Although these strategies were instrumental in defeating their enemies, plague also took a toll on the armies deploying these weapons, and on the hometowns of surviving soldiers. The use of plague in the attack on Kaffa may have been the cause of the second wave of the Black Death that wiped out much of Europe.


Smallpox was used by the English general, Sir Jeffrey Amherst, during the French and Indian War in 1767. Blankets and handkerchiefs from soldiers with smallpox were sold to Native Americans loyal to the French. Francisco Pizzarro used similar techniques against the native population of Peru in the 16th century. And, Captain Ecuyer of the Royal Americans presented smallpox contaminated blankets and handkerchiefs as gifts to Native Americans.

The use of biological warfare continued throughout history and was exploited during the first and second World Wars.

Marine Aquarium in Venice: New Venetian Museum of Natural History

The Museum of Natural History is located in the centre of Venice, on the Grand Canal. An aquarium housing fish from the reefs is already in place.

Location of the Museum in Venice

The Fondego dei Turchi (which houses the new aquarium) is not far from the Rialto Bridge in the centre of Venice. It is well signed and easily walkable, but perhaps the most interesting way to reach it is by ‘Traghetto’. This service uses the traditional gondola to ferry tourists (and Venetians) across the Grand Canal for a fee of 50 cents (much cheaper than hiring a gondola!). The one you want is from San Marcuola to the Fóndaco dei Turchi.

Marine Aquarium

The 5,000 litre aquarium has most of the fifty or so species of fish that live on the reefs that separate the lagoon from the Adriatic. This is one of the three ways to look at fish in Venice, the other two being in the wonderful fish-market and on your plate in the superb restaurants!

Seafood in Venice

It should not come as a surprise to find that a city surrounded by the sea offers some of the best seafood in the world. Mantis Shrimps appear in most seafood starters, and then again in many ‘second plates’ with spaghetti or tagliatelle. The best ‘third plate’ for a marine biologist is, of course, grilled fish – usually at least three species, and always including sea-bass and sea-bream.

Travel in Venice

Because the city has no traffic or hills walking is a pleasure (outside the peak tourist season!), and tourist tickets for the ‘Vaporetti’ are relatively cheap (currently 30 Euros for 72 hours unlimited travel). With a combination of these two modes of transport the whole city is easily accessible, and the islands and Lido can be explored. The only tiring bit is the bridges – there are thousands of steps to be negociated. Every time you cross one of the narrow canals you will have to climb up the steep stone steps, and calves will ache after a busy day of sight-seeing.

Arriving by Boat

It is possible to fly into Marco Polo Airport on the mainland and get a boat out to Venice itself, and this must be the most romantic and interesting way to arrive. There is also a mainline railway station in Venice, and a road-bridge which allows access by bus or coach. Once there, of course, it is all boats or ‘Shanks’s pony’, and it is remarkable how quickly one forgets about traffic (this can be dangerous on return to the Italian mainland!).

Whatever other tourist activities are contemplated it is a ‘must’ for all marine biologists to visit the natural history museum and ‘mess about in boats’!

Oceanography: Marine Biology Chemistry Physics Geology and Engineering

The Compact Oxford English Dictionary defines oceanography as ‘the branch of science concerned with the physical and biological properties and phenomena of the sea’.

Branches of Oceanography

  • Marine Biology – Marine Biologists study everything that lives in the oceans. This includes all marine plants and animals, as well as micro-organisms. It also occupies itself with the ecology of these many organisms, from the study of the requirements of individual species upto the consideration of entire habitats and how they work.
  • Marine Chemistry – The Chemists are interested in the way the sea interacts with the atmosphere and with the complex mixture of compounds that go to make up sea-water. When one considers the extremes of temperature and pressure that can exist within the oceans this chemistry becomes very complicated.
  • Marine Geology – Geologists look at the rocks and sediments that go to make the sea-bed, and at the way the tectonic plates move. They are also interested in the materials that come up to the ocean floor through volcanic activity
  • Physical Oceanography – Physical Oceanographers concern themselves with ocean currents, the tides and the properties of waves. Differences of temperature, salinity and pressure are also part of their remit.
  • Marine Engineering – Our use of the oceans’ resources requires engineers to design and build things as diverse as ships, submersibles and oil platforms. Conditions in, on, and under the sea can be extreme and the challenges that marine engineers face are enormous.

Careers in Oceanography

Obviously you will need to decide which branch of oceanography appeals most, and then go on to study it in depth. Not all oceanographers ride around in boats, and not all marine biologists play with dolphins – there are very many Careers in Oceanography, Marine Science & Marine Biology. It is always a good idea to have an ultimate goal in mind when you begin your studies, but it is equally important to be flexible and consider new possibilities. You will probably only become aware of your abilities and interests as your studies progress, and you will hear about job opportunities that you did not know existed – indeed some of them might not yet exist! (Who could have imagined becoming a computer programmer before the invention of computers?)

Two Famous Oceanographers

  • Jacques Cousteau must be one of the most famous oceanographers of the last century, he was a writer, film-maker and involved in the invention of the aqualung and scuba diving.

Charles Darwin is best known for his theory of evolution, but early in his life he was a keen marine biologist and during his voyage on HMS Beagle he studied many marine phenomena – surely he must rank as an ‘honorary oceanographer’ at least!

Probiotics Improve Ulcerative Colitis: Beneficial Bacteria Also Helpful in Irritable Bowel Syndrome

Symptoms of ulcerative colitis, as well as those of irritable bowel syndrome, can be very painful and disruptive. Abdominal pain, flatulence, bloating, diarrhea and/or constipation (and sometimes both alternating), anemia, and fatigue are common.

A review of some of the studies can help those who suffer with these disorders consider probiotics as a therapeutic option. Probiotics are beneficial bacteria that offer several benefits for people who have various gastrointestinal disorders. Those benefits include reducing the number of “bad” or harmful bacteria, reducing inflammation, increasing the number of anti-inflammatory molecules in the intestinal tract, and increasing the mucus layer in the gut, which protects it against damaging microorganisms.

Probiotics and Ulcerative Colitis

The most recent study, published in the World Journal of Gastroenterology, reports that four strains of probiotics (E. faecalis, L. acidophilus, C. butyricum, and B. adolescentis) are helpful in relieving symptoms of ulcerative colitis. The most effective strain, however, was E. faecalis.

A previous study, conducted at the University of Alberta, showed that 86 percent of the patients with moderate to severe ulcerative colitis who took a mixture of eight probiotics strains daily for six weeks experienced relief: 63 percent achieved remission and another 23 percent had improved symptoms and healing of the colon’s lining.

The eight strains included Lactobacillus casei, L. palntanum, L. acidophilus, L. delbrueckii sub sp. bulgaricus, Bifidobacterium longum, B. breve, B. infantis, and Streptococcus salivarius sub sp. thermophilus. None of the participants experienced any ill effects from taking the probiotics.

Probiotics and Irritable Bowel Syndrome

When investigators reviewed 19 controlled trials that included 1,628 patients with irritable bowel syndrome (IBS) in 2014, they found that probiotics were effective in relieving symptoms, but they could not determine whether one probiotic or a combination of probiotics was necessary.

In a study at The Mount Sinai School of Medicine in New York, experts found that a multi-strain probiotic significantly reduced the frequency of diarrhea in 84 patients with IBS compared with placebo. And in yet another study, this time in 59 children and teenagers, multiple strains of probiotics were significantly more effective than placebo in relieving symptoms.

Use of Probiotics

Overall, the research indicates that taking more than one strain of probiotics is most effective in relieving symptoms of ulcerative colitis and irritable bowel syndrome. The addition of prebiotics, which support the growth and maintenance of probiotics in the gut, as well as provide other benefits, may also be helpful. You should consult your health-care provider before starting a probiotics program.

Herbal Help for Ulcerative Colitis: Inflammatory Bowel Diseases & Herbal Medicine

If you’re one of the 500,000 Americans suffering from the inflammatory bowel disease that doctors call ulcerative colitis, you may be looking to herbal medicine for help. Though doctors don’t understand exactly what causes ulcerative colitis, emerging research suggests that certain herbal medications, coupled with dietary changes, may give ulcerative colitis sufferers more control over this painful condition.

Multivitamins for Ulcerative Colitis

People with ulcerative colitis often suffer severe bouts of diarrhea. This, coupled with decreased nutrient absorption in the colon, makes ulcerative colitis sufferers especially vulnerable to malnutrition. Though there’s no credible research linking any specific vitamin or mineral to a decreased risk of colitis flare-ups, most ulcerative colitis sufferers are advised to take a daily multivitamin.

Probiotics for Ulcerative Colitis

Probiotics aren’t actually herbal medicines but some preliminary human studies suggest that supplements of “good” bacteria like lactobacillus may help prevent ulcerative colitis flare-ups.

Flaxseed Oil for Ulcerative Colitis

Omega-3 fatty acid supplements don’t perform as well as prescription medications at preventing flare-ups, but some studies have found that coupling omega-3 supplements with the drug sulfasalazine may increase the effectiveness of the prescription drug. One of the richest herbal sources of omega-3 fatty acids is flaxseed oil.

Bromelain for Ulcerative Colitis

bromelain, which is an enzyme traditionally associated with improved digestion, may also help colitis sufferers better digest food.

Psyllium for Ulcerative Colitis

Ulcerative colitis sufferers are often urged to observe a bland, low-fiber diet during flare-ups so it may seem odd that psyllium, one of the best sources of natural fiber, is gaining respect among colitis researchers. Between flare-ups, psyllium may help normalize bowel movements and decrease recurrence of symptoms.

Other Herbs for Ulcerative Colitis

Other herbs commonly recommended for ulcerative colitis, but which aren’t supported by research, include:

  • Marshmallow root
  • Cat’s claw
  • Wild Indigo
  • Siberian ginseng
  • Green tea
  • Wild yam
  • German chamomile

Some, like marshmallow root and cat’s claw, have long been regarded as soothing to the digestive tract. Others, like green tea, have anti-inflammatory properties.

Before you begin an herbal regimen for your ulcerative colitis, talk to your doctor. Herbal medicines are often unproven and can interact with prescription medications in ways you and your doctor may not suspect. Remember, any herbal medicine capable of causing positive change in your body is also capable of side effects.

Only your doctor can tell you if herbal medicine can help your ulcerative colitis. But today, you have more treatment options than ever before.