World Penguin Day: Overfishing and climate change impacts penguin populations

World Penguin Day is celebrated on the 25th April every year. This coincides roughly with the start of the annual northward migration of the five Antarctic species of penguins.

Image: Wikimedia Commons

The State Of Antarctic Penguins 2017 report, released today by non-profit organisation Oceanites, calculated the number of penguins in Antarctica at 12 million. The report uses satellite technology to help assess the bird numbers over huge areas and across seasons.

Adélie and chinstrap penguin numbers in Antarctica have declined rapidly over the last few years. As global warming has affected the ice caps where the birds live, they are particularly vulnerable.

Outside of the Antarctic, penguin populations are not faring that much better. Twelve out of the 18 penguin species in the world are facing population decline. According to the International Union for Conservation of Nature’s Red List, 10 of the 18 are either endangered or vulnerable.

In South Africa, penguin population has fallen by 70 per cent in the last twelve years. Penguins complete with commercial fisherman and as sardines and anchovies stocks are depleted they struggle to feed their young.

Overfishing, especially dragnet fishing to make fishmeal that goes on to feed farmed salmon, chickens and other livestock affects many marine species. The decline in penguin numbers is yet another side effect of the emptying of the oceans.

​Glynn Davies, WWF’s executive director of global programmes, said: “The decline of species is reaching a critical point and we cannot ignore the role of unsustainable livestock production.“If nature is to recover, we need to work together and encourage sustainable farming systems which will limit pollution, reduce habitat loss and restore species numbers.”

Penguins live across the Southern Hemisphere from the southern Australian coast to the Galapagos Islands and Peru. They occupy a huge variety of habitats from the extreme frozen wastelands of Subantarctic Islands to urbanised beaches in South Africa and forests in New Zealand. Penguins are one of the most popular species of birds, they have a friendly nature and a cuddly appearance. Zoos and popular culture have kept them in the forefront of the public’s imagination from Chilly Willy in the 1950s to Happy Feet.  

However the threat of environmental destruction, including oil spills and illegal egg harvesting threatens all species of penguins. With World Penguin Day 2017, WWF, Bird Life Europe and Compassion in World Farming hope to highlight the impact humans have on these birds and other marine species.

Published Nouse Online 25/04/2017

Warm winters drive the spread of Lyme disease

As climate change drives the spread of Lyme disease carrying ticks across new areas of the Northern Hemisphere, we still have no human vaccine against the infection. Neither is there a medical consensus about the existence of “chronic Lyme disease”, the symptom complex that some sufferers experience even after being treated for the initial infection.

Lyme disease, or Lyme borreliosis is a bacterial infection of Borrelia burgdorferi spread to humans by infected tick bites. The bite can leave a bulls-eye shaped rash and initial infection causes fever, headache and exhaustion. If left untreated, Lyme disease may develop over several weeks, months or years, leading to inflammatory arthritis, heart problems, issues of the nervous system and even meningitis.

Imagr: Flickr

Lyme borreliosis is the most common disease spread by ticks in North America and is estimated to affect at least 65,000 people a year in Europe alone. The autopsy of Ötizi the Iceman, a 5,300 year old mummy found in the Ötztal Alps between Austria and Italy discovered the DNA of Borrelia burgdorferi, making him the earliest known human to have suffered from Lyme disease,

Since 2001, cases of Lyme disease in the UK have increased ten-fold. In the US, the Centres for Disease Control has called the increased incidence of infection “a major US public health problem”. This seems to be linked to the warmer winters we have been experiencing over the last decade.

As global warming increases world average temperatures, Lyme disease is spreading outside of its usual territories. Whilst those who live in Lyme disease zones are aware of how to avoid contact with ticks, the spread of the insects to new areas means those less familiar with tick awareness will begin to encounter the disease.

When a tick initially bites, it is only the size of a poppy seed and some people do not display the typical “bulls-eye” rash that would otherwise signify infection with Lyme disease. Likewise, initial flu-like symptoms are easily misdiagnosed and because antibodies to Lyme disease can take weeks to develop, early tests may miss it.

The best approach to combat Lyme disease would be vaccination of those at risk, and in 1998 GSK released Lymerix, an FDA approved human vaccine against Borrelia burgdorferi. However, some recipients of this vaccine claimed it had caused them to suffer autoimmune arthritis, and lead by pressure from various anti-vax groups, Lymerix was withdrawn from the market.

The FDA has since confirmed there was no link between the Lyme vaccine and any autoimmune side effects, but the damage to the vaccines image was done and Lymerix was declared unmarketable by GSK. There are, however, various animal-approved vaccines for Lyme disease, so most farm animals and pets are protected.

The French biotech company Valneva is working on a new human Lyme vaccine that will improve on Lymerix by immunising recipients against all five strains of the disease, however it is still only in the early stages of human trails.

In the meantime, if you plan on hiking in a “high risk” area, such as the North York moors, read up on your anti-tick precautions. Lyme disease can be treated with a two or four week course of antibiotics, and if you suspect you have been bitten by a tick you should seek medical advice.

Published Nouse Online 21/04/2017

Marmite is good for the brain, York study suggests

Eating a spoonful of Marmite everyday could have a positive impact on your brain’s health, researchers at York have found.

A group from the University of York’s Department of Psychology have identified a potential link between Marmite and the increase of gamma-amino butyric acid (GABA) – a chemical messenger which is associated with healthy brain function.

Marmite contains a high concentration of vitamin B12 Image:Flickr

Dr Daniel Baker, Lecturer in the Department of Psychology and senior author of the paper, said: “The high concentration of Vitamin B12 in Marmite is likely to be the primary factor behind results showing a significant reduction in participants’ responsiveness to visual stimuli.”

The study looked at 28 healthy volunteers who were split into two groups; half ate a teaspoon of Marmite every day for a month whilst the control group where given peanut butter.

The participants’ responses to visual stimuli were measured and they recorded electrical activity in the brain using electroencephalography (EEG). Subjects that had been eating the “yeast extract product” saw a reduction of around 30% in the brain’s response to the visual stimuli.

GABA is an inhibitory neurotransmitter; it reduces the excitability of neurons in the brain, as a delicate balance of activity is needed for brain health. Abnormal levels of GABA are associated with epilepsy, autism and depression.

Anika Smith, PhD student in York’s Department of Psychology and first author of the study, said: “These results suggest that dietary choices can affect the cortical processes of excitation and inhibition – consistent with increased levels of GABA – that are vital in maintaining a healthy brain.

“As the effects of Marmite consumption took around eight weeks to wear off after participants stopped the study, this suggests that dietary changes could potentially have long-term effects on brain function.

“This is a really promising first example of how dietary interventions can alter cortical processes, and a great starting point for exploring whether a more refined version of this technique could have some medical or therapeutic applications in the future. Of course, further research is needed to confirm and investigate this, but the study is an excellent basis for this.”

Published Nouse Online 5/4/17