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4th of May 2021:

Albatros Hurleur©Bénédicte Martin

This chronicle is translated from a tribune in the french Newspaper Libération:

The Wandering Albatross – An ecological chronicle

David Grémillet

Nectar from urban gardens to the rescue of insects

A sunny spring day in the Deux-Sèvres. In my garden, bees and bumblebees are buzzing. Just on the other side of the dry stone wall, the agricultural plot is silent. Populations of pollinating insects are collapsing in Western Europe, mainly due to lack of food. Are populated areas refuges for all the little beasts?

Colleagues (1) investigated this question in 12 locations in the UK, comparing the amount of nectar produced by flowers in cities, agricultural areas and protected areas. To do this, they collected as much nectar as possible from the different flowers with a micropipette, becoming foragers themselves.  To their great surprise, there was on average no more nectar available for insects in the city than in agricultural areas and protected areas. However, within urban areas, some fully concreted habitats were extremely poor, while home gardens produced 85% of all available nectar, four times more than public parks. Thus, insects have much more food available to them in a garden than on an agricultural area. This urban nectar comes from a wide variety of plants, which contributes to its quality and extends the period of the year during which it is available. The second surprise was that 83% of the nectar in the gardens was produced by exotic plants. These species are often considered to be “beautiful and useless”, as they do little to benefit local biodiversity. Some are even invasive and potentially harmful. In fact, the study by British academics indicates that exotic flowering plants may have become essential for the survival of insects in our urban landscapes. Of the 536 flowering plants they studied, the scientists point out that species such as borage and butterfly tree (from the Middle East and China respectively) are excellent sources of nectar. For public parks, they recommend reserving certain areas to grow mixed flowers, which produce 16 times more nectar than a lawn.

This study is sure to delight urban gardeners, where flowering plants are now taking on a militant air; I’ll be thinking of them as I watch the bees foraging in the borage beds that bloom on the edge of my vegetable garden.

(1) Tew, N. E., Memmott, J., Vaughan, I. P., Bird, S., Stone, G. N., Potts, S. G., & Baldock, K. C. (2021). Quantifying nectar production by flowering plants in urban and rural landscapes. Journal of Ecology 109: 1747-1757.

Bourdon des champs©Getty

Bombus pascuorum (Photo credit: Getty)

17th of April 2021:

Albatros Hurleur©Bénédicte Martin

This chronicle is translated from a tribune in the french Newspaper Libération:

The Wandering Albatross – An ecological chronicle

David Grémillet

In the cool of the air conditioning

Phoenix, Arizona, the hottest city in the United States. Three months of the year, the daytime temperature exceeds 40°C. Since the invention of air conditioning a century ago, wealthy humans have lived in a cool bubble. Around them, animals are increasingly roasting in the Arizona sun as urban activity creates a deadly heat island; even rattlesnakes are fleeing.

More than 100 bird species are threatened by climate change in Arizona, but rosy-faced lovebirds found a trick. These small, colourful parrots have come a long way; their ancestors were captured in southern Africa, and shipped to American pet shops. Some escaped and, from the 1980s, an urban population settled in Phoenix. Several thousand now live in the metropolis, colonising the palm trees and cacti of the most wooded gardens, in place of the dry forests and savannahs of their origins. For the past decade, researchers at Arizona State University have seen them indulge in a strange activity. On the hottest afternoons between June and October, the lovebirds perch on the air vents of some buildings. At first sight, this does not seem to be a good idea, as one can imagine these ducts pulsating with the overheated air of air-conditioning units. Perching on these giant hairdryers would therefore be appropriate in winter, as European magpies do on some chimneys, but not during a heat wave. The puzzled researchers turned to the university’s technical services and solved the puzzle: the system in question dates back to the 1960s, when oil orgies made it possible to spend lavishly, including on artificially cooled air. Thus, the air vents frequented by the cute parrots are used to ventilate rooms cooled by air conditioners, evacuating deliciously cool air. The lovebirds literally queue up to swoon, as we open a fridge in the middle of a heatwave to catch a bit of freshness.

Why only these birds from elsewhere have figured out the trick? It is surprising not to see local creatures, such as mockingbirds and hummingbirds, also visiting the cooling vents. Of course, the manoeuvre is very technical as they have to perch on particularly slippery metal slats, with all the skill and intelligence of a parrot to stay on them. But there is more: the immigrants are intrepid and inventive. Where local species are content to endure the relentless heat, newcomers adapt and persist.

Reference: Mills, R., & McGraw, K. J. (2021). Cool birds: facultative use by an introduced species of mechanical air conditioning systems during extremely hot outdoor conditions. Biology Letters, 17(3), 20200813.

Agapornis_roseicollis_roseicollis©Charles J. Sharp

A pair of rosy-faced lovebirds (Photo credit: Charles J. Sharp)

November 2020:

Online seminar

No way home : Migration and mortality in a resilient seabird, the northern gannet

Fou bagué - David Grémillet

May 2020:

index

The Oceans with SARS-CoV2 – A nine-point agenda for immediate action

April 2020:

A goldfish memory

My old parents were confined for two months to their house in the Allier. In order to be able to supply them, my sister Sophie and her companion Daniel moved into a nearby gîte. This way, they escaped being confined to an apartment and could enjoy a beautiful garden with a small pond. Frogs and birds attracted by the coolness delighted their ears with their songs. The many goldfish in the pond also contributed to a very Zen atmosphere. For the first few days, the scaly companions basked on the surface, then came the grey heron. Unexpectedly in the middle of the city, the big bird had spotted the small pond and its inhabitants. It cautiously perched first in the tall trees, then glided quickly to the edge of the pond to quickly grab a goldfish, swallow it and fly back to the air.

In a flash, all the surviving fish disappeared from the surface to hide in the murky depths of the pond. Some had witnessed the disappearance of their unfortunate companion first hand, while others followed the collective movement. “This is what we call the landscape of fear,” I said to my sister Sophie when she told me on the phone, “the presence of the predator has changed the fish’s environment and they will avoid the surface as long as they remember the presence of the heron”. We made some bets as to the persistence of this frightened landscape. Sophie and Daniel checked the surface of the pond every day, but the goldfish defied all our predictions: they only returned to the surface two weeks after the heron’s passage.

And this is how we finally learn what is meant by “a goldfish memory”.

March 2020:

The nurse’s mask

My parents, 177 years between them, are self-isolating in Bourbonnais. Children of war and veterans of medicine, they spent their lives healing others. Today they know that if they are hospitalized, they will not be resuscitated.

In the meantime, my mother loves to unfold a century of family history and tells me this: “In Lyon in 1949, I was an apprentice nurse at a home for sick children. On the first day the boss called us: ‘Ladies, your masks will be in organza*; the children must be able to see your smiles’”.

If soon, coughing, I meet a staff in FFP2 suits, gloves and masks, it is not the rout of a hospital system ravaged by four decades of budget cuts that I will think of, but my mother’s smile.

*a type of thin, transparent cloth made of silk or artificial fabric

February 2020:

France’s double game with environmental issuesours

January 2020:

Online conference:

Daniel Pauly – Un Océan de combats

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