Culling in the name of…

If you have even a passing interest in the natural world, you will have most likely heard the phrase “invasive species”. By definition, a deliberate or accidental release of a species to an area beyond its natural environment where it then multiplies and causes damage to that environment and the native wildlife that relies on it. I discussed the UK issue of invasive species briefly last year and in the context of Muntjac and Black Hairstreak butterfly too.

Reeves' Muntjac Deer

Ecologist and conservationist Hugh Warwick tackles the issue in much more depth in his latest book – Cull of the Wild. Warwick is, as most of us are, not keen on killing in the name of and recognises that the arguments and issues regarding the culling of invasive species where they threaten the very existence of native species and ecosystems are still very complicated.

Cover of Hugh Warwick's book - Cull of the Wild

In Cull of the Wild, he discusses how different approaches to control have been tried worldwide. The grey versus red squirrels, the cane toads in Australia, rats, even Pablo Escobar’s hippos and the Burmese python trade.

Warwick, a former vegan and now a self-confessed meat-eschewing vague-an, points out that millions of animals are killed, or culled, every year in the name of conservation, invasive species, feral populations, domestic animals. Sadly, much of this killing is cruel and essentially unregulated. To quote from Warwick’s introduction:

“We deserve an honest conversation about conservation. To do that we need to establish one very important point. Conservation, wildlife management, and the ecology that underpins them both, is really complicated. Add to this one more variable: people with differing perspectives. Now, it becomes close to impossible to solve the very real problems with which we are confronted. Complicated problems rarely have simple solutions…”

There are, we learn, no absolutes. Each invasive case has nuance where humans have destroyed habitat and the native species that once filled a niche are long gone, an incomer might fill that space and become prevalent. It might be that the new species brings benefits to that environment, perhaps reducing plant overgrowth and opening up biodiversity that resurrects the habitat.

The beautiful Box-tree moth, Cydalima perspectalis, represents an interesting example of the kind of nuance we have to address. It arrived in the UK around 2007, presumably hitching a ride on imported Asian strains of box-tree, Buxus. Unfortunately, it has spread and thrived, ravaging decorative box hedges across southern England.

Box-tree Moth

There is little that can be done to control this invasive species at this point in its history other than grubbing out its larval food plants, Buxus, and planting something else. Insectidal sprays are not the answer as they kill the native species too, pheromone traps are of limited use and while they kill some of the males there will always be another to fertilise the female’s eggs on one’s box hedge, and picking off caterpillars for, ahem, disposal, is not the most pleasant way to spend a lazy Sunday afternoon.

However, to talk of the lack of the nuance and the lack of absolutes, it’s worth noting that Blackbirds are starting to recognise the larvae of this moth as a rich food source. So, whereas the presence of the moth is essentially well-balanced in its native environment, there is hope that this might happen naturally here too.

It is unlikely that many of the problematic invasive species we must cope with will naturalise in that way, so there may well forever be a need to find ways to control them or live with them. Warwick offers much for our consideration of the nuances of invasion.

Rinse your recycling

Rinsing food packaging before putting in your recycling bin is critical to making the process as efficient and as effective as possible. Efficient recycling processes can significantly reduce the environmental impact compared to producing new materials from virgin resources.

Rinsing packaging helps reduce contamination in the recycling stream. Contaminated materials can lead to lower-quality recyclables, which may be rejected or require additional processing, thereby increasing costs and energy consumption. Higher-quality recycled materials fetch better prices in the market and have broader applications, contributing to a more sustainable recycling industry.

Rinsing packaging does require additional water usage. However, the amount of water needed for rinsing is generally minimal compared to other household activities. If you can use grey water, or even collected rainwater, for rinsing all the better. The simplest approach is just to add the dirty packaging to the end of your normal washing up. There is no need to put tins, cans, or plastic pots in the dishwasher, of course.

Rinsing also avoids residues that can affect the maintenance requirements and lifespan of recycling equipment. Residue buildup can lead to equipment corrosion, increased wear and tear, and the need for more frequent cleaning and maintenance cycles, all of which contribute to higher operational costs and resource usage.

Encouraging rinsing as a standard practice can also have broader effects on environmental awareness and behaviour. It reinforces the importance of proper waste management and encourages individuals to consider the environmental consequences of their actions.

Invasive species in the UK

Invasive species, a term referring to non-native species introduced to new environments, often establish self-sustaining populations with negative impacts on local ecosystems, economies, or human health.

These invaders, encompassing plants, animals, fungi, or microorganisms (refer to the foot of this article for examples), typically arrive due to human activities such as trade, travel, or intentional release. In rare cases, invasive species might reach the UK through natural avenues, such as animal migration or wind dispersal. Climate change exacerbates the situation, creating new ecological niches due to shifts in temperature and persistent weather changes. Alterations in landscape, urbanization, and habitat loss add pressure to natural ecosystems while simultaneously creating new opportunities for invasive species.

In the context of the United Kingdom, invasive species present significant challenges for various reasons:

Ecological impact: Invasive species can outcompete native species for resources including food, water, and habitat. They may have no natural predators in their new environment, allowing their populations to grow unchecked. This can lead to the decline or extinction of native species, disrupting the balance of the ecosystem.

Biodiversity loss: The displacement of native species by invasive ones can lead to a loss of biodiversity. Native species are often adapted to specific ecological niches, and the introduction of invasive species can disrupt these relationships, leading to a reduction in overall biodiversity.

Human health and safety: Some invasive species can pose risks to human health. For instance, certain plants may be toxic, and some animals may carry diseases that can affect humans. Additionally, invasive species can create safety hazards; for example, certain plants or animals might be harmful if they interfere with buildings, bridges, transportation systems.

Economic consequences: Invasive species can have economic impacts on agriculture, fisheries, and forestry. For example, invasive plants can reduce crop yields, while invasive animals may damage crops or compete with native species for resources. Invasive species can also impact infrastructure, such as clogging waterways or damaging buildings.

Increased management costs: Controlling and managing invasive species can be expensive. Governments, communities, and individuals may need to invest significant resources in efforts to control or eradicate invasive species and mitigate their impacts.

In the UK, various organizations and initiatives actively monitor and address the issue of invasive species. This global concern necessitates efforts to prevent introductions, manage existing populations, and control their impacts, preserving biodiversity, ecosystem health, and human well-being.

It’s crucial to note that some invasive species in the UK have been present for centuries, becoming integrated into local ecosystems. For example, the sycamore, recently in the news having been vandalistically felled at Sycamore Gap on Hadrian’s Wall in Northumberland, had long been part of the landscape but sycamores arrived with the Romans. Distinguishing between long-established non-native species and recent arrivals is crucial for effective management.

Despite confounding factors, certain invasive species contribute to ecosystem services, such as soil stabilization, water filtration, and habitat provision. Invasive crayfish used as food in mainland Europe have established themselves in the lakes of France and Spain and this in turn has allowed ostensibly African and Mediterranean birds such as the Great White Egret and Glossy Ibis to spread further north. It was only a short hop for them across the English Channel to the UK where they are no beginning to establish themselves, without apparent harm to native species or ecosystems it seems.

Indeed, some invasive species may enhance overall biodiversity by providing new habitats or food sources for native species, fostering a more diverse and resilient ecosystem. Additionally, there’s potential for utilizing invasive species in agriculture, forestry, and horticulture.

Examples of invasive species present in the UK

Plants:

American Skunk Cabbage (Lysichiton americanus)
Australian Swamp Stonecrop (Crassula helmsii)
Chilean Rhubarb (Gunnera tinctoria)
Cotoneaster species (Cotoneaster sp.)
Cotula Silverweed (Argentina anserina)
Curly Waterweed (Lagarosiphon major)
Floating Pennywort (Hydrocotyle ranunculoides)
Floating Water Plantain (Luronium natans)
Giant Hogweed (Heracleum mantegazzianum)
Himalayan Balsam (Impatiens glandulifera)
Hottentot Fig (Carpobrotus edulis)
Japanese Knotweed (Fallopia japonica)
Japanese Rose (Rosa rugosa)
Parrot’s Feather (Myriophyllum aquaticum)
Rhododendron (Rhododendron ponticum)
Small-Flowered Water-Weed (Elodea nuttallii)
Spanish Bluebell (Hyacinthoides hispanica)
Water Fern (Azolla filiculoides)
Water Primrose (Ludwigia grandiflora)
Winter Heliotrope (Petasites fragrans)
Yellow Azolla (Azolla caroliniana)

Invertebrates:

Asian Hornet (Vespa velutina nigrithorax)
Asian Tiger Mosquito (Aedes albopictus)
Box-tree Moth (Cydalima perspectalis)
Chinese Mitten Crab (Eriocheir sinensis)
Emerald Ash Borer (Agrilus planipennis)
Harlequin Ladybird (Harmonia axyridis)
Harlequin Shrimp (Hymenocera picta)
Horse Chestnut Leaf Miner (Cameraria ohridella)
New Zealand Flatworm (Arthurdendyus triangulatus)
New Zealand Mud Snail (Potamopyrgus antipodarum)
Oak Pinhole Borer beetle (Platypus cylindrus)
Oak Processionary Moth (Thaumetopea processionea)
Quagga Mussel (Dreissena rostriformis bugensis)
Red Swamp Crayfish (Procambarus clarkii)
Rosemary Beetle (Chrysolina americana)
Signal Crayfish (Pacifastacus leniusculus)
Spanish Slug (Arion vulgaris)
White-Legged Shrimp (Litopenaeus vannamei)
Zebra Mussel (Dreissena polymorpha)

Vertebrates:

American Bullfrog (Lithobates catesbeianus)
American Mink (Neovison vison)
Black Rat (Rattus rattus)
Canada Goose (Branta canadensis)
Chinese Water Deer (Hydropotes inermis)
Egyptian Goose (Alopochen aegyptiaca)
Grey Squirrel (Sciurus carolinensis)
Muntjac Deer (Muntiacus reevesi)
Parakeet sp.
Pumpkinseed Sunfish (Lepomis gibbosus)
Raccoon (Procyon lotor)
Red-Eared Slider (Trachemys scripta elegans)
Ruddy Duck (Oxyura jamaicensis)
Sika Deer (Cervus nippon)
The Red-Eared Slider terrapin (Trachemys scripta elegans)
Topmouth Gudgeon (Pseudorasbora parva)
Wallaby (Macropus sp.)
Yellow-Bellied Slider terrapin (Trachemys scripta scripta)

Fungi/Microbes:

Chalara Ash Dieback (Hymenoscyphus fraxineus)
Dutch Elm Disease (Ophiostoma ulmi)
Horse Chestnut Bleeding Canker (Pseudomonas syringae pv. aesculi)
Phytophthora Ramorum (Phytophthora ramorum)
Sudden Oak Death (Phytophthora sp.)

Are crypto currencies destroying the planet?

TL:DR – Bitcoin mining uses vast arrays of energy-hungry computers many of which are powered with an unsustainable, non-renewable energy supply, generating enormous carbon emissions. It is estimated that Bitcoin is currently wasting 140 terawatt-hours of electricity annually and producing 70 megatonnes of carbon emissions each year.


Bitcoin is a form of digital currency. Each Bitcoin has a digital ledger, a blockchain, that records all transactions and is at the heart of the value in the currency. Bitcoin transactions are typically irreversible and can be made anonymously, providing a level of privacy. It operates on a decentralized, peer-to-peer network independently of governments, banks or any financial authority. It was ostensibly created by Satoshi Nakamoto in 2009, but that pseudonym may represent an unknown individual or a group of people.

The way in which Bitcoin was created means that there is a known and limited supply. The total number of Bitcoins that can ever exist is capped at 21 million, making it a finite digital asset. Scarcity, of course, can be seen as giving Bitcoin value and it has become a popular form of alternative investment. The value of Bitcoin can fluctuate wildly with no physical asset, such as gold or a commodity to underpin it nor government backing. Its value is determined solely by supply and demand in the crypto market.

None of this is free. Bitcoin is a digital entity and must be sustained by a network of computers all using electricity. Indeed, each Bitcoin transaction created when someone sends or receives a Bitcoin has to be verified and this is done by a process called mining. Mining involves nodes (computers) in the Bitcoin network solving a complex mathematical problem to validate the transaction before it can be added to the digital ledger, the blockchain.

Now, the obvious question arises why would a person with a computer or an array of computers use their resources to solve those mathematical problems to validate Bitcoin transactions to add to the digital ledgers? The answer is that the owner of the computer that solves the problem and validates the transaction first is rewarded with Bitcoin! Validating transactions, which usually takes about ten minutes for a powerful computer, is a competition with Bitcoin as its prize.

The mathematical problems that miners must solve require significant computational power and energy to undertake the so-called Proof-of-Work (PoW)*. The solution to the mathematical problem is the “hash” a unique cryptographic code that verifies each transaction and locks the new link in place in the blockchain. A third party hoping to hack and so steal a Bitcoin would need unimaginable computer resources to solve the thousands of hash codes in a single Bitcoin. The PoW system makes Bitcoin validation decentralised and secure.

The electricity consumption in Bitcoin mining is enormous. The primarily attributed to the computational power required to solve the PoW puzzle, the cooling and infrastructure needed to run the mining hardware, and the continuous operation of the mining equipment. The University of Cambridge’s Bitcoin Electricity Consumption Index currently estimates that the annual power usage is almost 140 terawatt-hours. That is roughly half the electricity usage of Finland or about a third of that of Venezuela!

A particularly cynical aspect of Bitcoin mining is the exploitation of cheap electricity in the developing world, which not only affects the environment detrimentally but reduces access and raises prices in those regions. That said, while it was originally China with the most Bitcoin mines, the US has gone into polluting pole position after China shut them down citing environmental reasons!

It seems obvious that Bitcoin mining is not an environmentally benign process. There are other crypto currencies that use other types of PoW puzzles and these too add to the power burden. That said, there is some effort underway to develop an alternative to PoW that would use far less power – Proof of Stake (PoS). Instead of miners solving complex mathematical problems, validators (or “stakers”) are chosen to validate transactions based on their ownership or “stake” of the cryptocurrency.

There seems to be no obvious solution to this growing problem. Good intentions rarely pass muster among the greedy and it is likely that crypto currencies will continue to consume huge amounts of electricity, generate huge carbon emissions, and as equipment fails or becomes obsolete produce even more electrical waste.

I’ve talked about all of this previously, but an NYT piece triggered me.


*The PoW puzzle in Bitcoin is a complex mathematical problem  involving finding a hash value that is numerically lower than a specific target value. This requires miners to perform extensive calculations using the SHA-256 algorithm, searching for a hash that starts with a certain number of leading zeros in its hexadecimal representation.

For example, let’s say the target value is represented in hexadecimal as “00000000F123456789ABCDEF123456789ABCDEF123456789ABCDEF123456789ABC”. Miners must try different inputs in combination with the transactions and the hash of the previous block, encrypt them using the SHA-256 hash function, and check if the resulting hash is a lower number than the set target value.

The first miner to find that lower number and so successfully solve the PoW puzzle gets to add a new block of transactions to the blockchain and is rewarded with newly created Bitcoins. This PoW puzzle serves as a security mechanism to prevent double spending, validate transactions, and maintain the integrity of the Bitcoin blockchain.

A foreboding of petrels

TL:DR – The problem of deteriorating plastic waste at sea and how it attracts birds to eat it when they really shouldn’t.


I have just finished reading the latest novel in Steve Burrows’ series of “birder murder” stories. This one was called A Foreboding of Petrels and hinges on apparently unconnected murders on the North Norfolk coast and at an environmental research station in The Antarctic.

The plot of the novel alludes to the Storm Petrel, perhaps the world’s most abundant avian species. It and related species have an incredibly sensitive sense of smell and can detect keystone odourant molecules on the wind. Compounds such as dimethyl sulfide (DMS) are released into atmosphere when other organisms are feasting on algae for instance. The compound thus attracts the predators to the places where their prey are themselves feasting.

A fulmar in flight against a rocky backdrop
The Fulmar is one of the procellariiforms, a group that also includes the petrels

The novel alludes to plastic waste in the oceans and how the combination of algal growth on that plastic waste coupled with degradation of the plastic through the action of seawater and sunlight could lead to the release of the same odourant molecules that attract these birds and lead to them ingesting plastic rather than prey. This is obviously detrimental to the birds’ health. Numerous studies discuss this possibility and provide evidence to support the hypothesis.

Dimethyl-sulfide-3D-vdW

DMS carried on the oceanic wind attracts predators, such as petrels, albatrosses, and fulmars, to food sources, and in the modern age, unfortunately, plastic waste. This chemical confusion is seemingly leading some pelagic bird species to ingest a lot of potentially lethal plastic waste instead of food.

A Blackcap in Winter

TL:DR – The Blackcap, Sylvia atricapilla, is commonly a summer visitor to the UK from sub-Saharan Africa. But in recent years, some birds that spend their summers in the east of Europe and would normally head for the Iberian peninsula or North Africa in winter have reached the UK where they found winter food on bird feeders. There is now evidence that these birds that overwinter in the UK are not mingling with the Iberian or African overwinterers when they go back to their breeding grounds in east Europe.


UPDATE: As of 13th March 2023, the male Blackcap that overwintered since mid-December in our garden is still here. The outside temperature has gone from freezing to about 17 Celsius, but he is showing no signs of departing just yet. He enjoyed mistletoe berries, pyracanthus berries and now most of those have gone, he pecks at suet balls in a feeder right outside our living room window.

It’s no wonder this little fellow looks so grumpy perched next to the mistletoe growing on our rowan tree…most other Blackcaps will be enjoying a much balmier winter on the Iberian Peninsula or even in Africa. We have had Blackcaps in our garden in winter for several years now. Never see them in the garden in summer though. We had a male and a female last winter. So far this winter, just this solitary male.

Blackcap overwintering in the UK
Blackcap overwintering in the UK

In recent years, a lot of migrating Blackcaps (Sylvia atricapilla) have headed west from eastern Europe for the winter instead of turning south. Their compasses seem to have lost calibration, perhaps due to climate change, but other factors may be at play. The species seems to be affected by climate change, a decalibration of their internal compasses, and perhaps moreover by the British wont to stock garden bird feeders and put out fat balls, which is not such a common practice on the continental mainland.

When they head back to their mating grounds in the spring, they are marginalised by the southerners it seems and two distinct groupings are observed. This is an early process in speciation whereby in the long-term we might see a sub-species emerge that no longer mates with the other.

A Glossy Ibis in Cambridge

UPDATE: As of November 2021, 6 at or close to Berry Fen.

I think I’ve now seen six of the eight or so Glossy Ibis (Plegadis falcinellus) that are in our locale at the moment. Two at RSPB Ouse Fen, three in Earith, and this one near The Cam in Chesterton. There are two more at RSPB Fen Drayton but my daily exercise has not coincided with theirs at that site. There are others further afield.

It is most likely that they are individuals that have flown in from a breeding ground in Southern Spain again to overwinter in East Anglia. Apparently, there was a pair in 2014 that built a nest in Lincolnshire, but didn’t breed. This kind of bird activity is occurring more commonly because of changing habitats and climate change.

The photo above is of a Glossy Ibis feeding on farmland adjacent to the river Cam in Chesterton, north of the city of Cambridge. It was no more than 40 metres away. Photographed with a Canon EOS 7d mark ii digital SLR fitted with a Sigma 150-600mm zoom lens. f/7, t 1/800s, ISO 400. The RAW image was imported with Rawtherapee and then post-processed with PaintShop Pro to crop and boost vibrancy and sharpness.

Egrets, I’ve seen a few – Cattle Egret

Back in the early 1990s, Mrs Sciencebase and I visited Botswana and Zimbabwe. It was wonderful. The people, the landscapes, the wildlife. There were so many superb species around such as Golden Weaver Birds, Oxpeckers, Superb Starlings, various storks, ibis, vultures, Fish Eagles, Eagle Owl, and Little Egrets (probably Cattle Egrets too).

We were quite confused on our return on a visit to the North Norfolk coast (a place that would become a favourite haunt) that we saw a Little Egret there. Over the next three decades or so little egrets seem to have become increasingly common in East Anglia and although it’s still lovely to see them, they’re almost commonplace. Five years ago the same couldn’t be said of another type of egret. The Great White Egret, but that too is becoming more common. Similarly, Cattle Egret (Bubulcus ibis).

Is it simply an effect of climate change? These ostensibly African birds spreading their wings and thus their range and reaching farther north with each passing year? Well, climate change is definitely playing a role in species distribution when it comes to birds and many other forms of life. But, it’s more subtle than that. Deliberately or inadvertent introduction of the Red Swamp Crayfish (Procambarus clarkii) in freshwater lakes across Europe is providing egrets of all flavours as well as cormorants and other species with a ready, but unaccustomed food source and this is allowing them to expand their numbers and their range. (Barbaresi and Gherardi 2000, Rodríguez et al. 2005)

The presence of the introduced North American crayfish, often known as the freshwater lobster, in the lakes of Northern France now means those egrets that were so rare this far north have but a short hop across the channel and upwards into East Anglia where they will find food and a foothold in small numbers.

It is perhaps only a matter of time before the red swamp crayfish becomes widespread in the freshwater lakes of The British Isles too and those egret numbers will rise still further.

We saw five Cattle Egrets in Fen Drayton this morning, feeding in between the hooves of a herd of cattle. Last winter we saw a flock of some 60 or so Little Egrets in the reserve that abuts the village and I have seen half a dozen Great White Egrets there (alongside lots of Little Egrets and lots of Grey Herons).

It’s possibly the same phenomenon leading to more frequent sightings of Glossy Ibis in East Anglia lately too.

The Quarrymen North of Cambridge

Yes, for they are men driving those diggers and lorries on the Cottenham quarry north of Cambridge. Didn’t see any women there. And, The proto-Beatles allusion in my title referencing The Quarrymen would have failed if there had been…

I drove down Long Drove once again, yesterday, dog and bins in tow, in the vain hope of spotting the Hooded Crow and the Iceland Gull that have been hanging around with the other corvids and gulls in this part of our village for months now. No sign in the fields opposite the dump and no sign on the quarry.

So, herewith a few snaps from the Drove of the quarry activity (they’ve shaved away the raised edge along the drove so you can see clearly into the site just standing alongside dog and car. There were a few gulls and crows but nothing Icelandic, despite the snow and nothing corvid.

As I understood it, as with virtually all of the East Anglian gravel and sand quarries, there might have been aspirations from consverators and ecologists to see this quarry converted into a nature reserve once they’ve scraped out everything they want from the Earth here. Unfortunately, there are no plans in place to make that happen and the contractors will simply “make good” the land and the scars they’ve created, which is a crying shame.

The Cumulus Dynasty

LIFE ON THE FEN EDGE – WITH SIR DAVID ATTENBRADLEY

EPISODE 4: THE CUMULUS DYNASTY

from the BBC, the British Bradcasting Corporation

Dusk

On the southern edge of the Cambridgeshire Fens.

As the sun dips below the horizon, voluptuous clouds skud with the wind across what at first glance appears to be a live action Turner painting, but lacking the bridges and the ships.

Clouds at higher altitude seem static and yet we know they too are moving gently as the wind picks up their fluffy forms and buffets them across the sky.

As the clouds darken and others catch the last glow of the sun’s burning ember we begin to wonder. Why has the British Bradcasting Corporation hired a narrator for this particular sequence. It is one of nature’s great mysteries. Unlocking those mysteries is my forte and yet sitting in this sound both with the apparently endless video stream of those clouds one struggles to find a key.

There are no Great White Sharks here, no Orca waking a seal from its lullaby, nor Cleesiastical herds of wildebeest sweeping majestically across the Serengeti. This is no secret life of plants, not Blue Planet, although admittedly there were a few patches of blue in the sky earlier in the day.

But, now, as the sun dips below the horizon once again, we begin to nod off, dreaming of an end to this episode or perhaps something startling to appear on that very horizon. A Gold Eagle, or even just a Kestrel would do. Perhaps a great flock CGI pterodactyls, but no, it’s just clouds. Cloud after cloud after blinking cloud.

And then just as we begin to nod off, another bloody cloud. When will it end? When will they finally let me retire? Maybe this is purgatory, maybe I’ve actually died and am now trapped in some kind of televisual limbo awaiting the eternal fate of my immortal soul. But, as I told you on Desert Island Discs, I don’t believe in any of that claptrap. Give me oblivion any day. Anything but these bloody clouds…

LIFE ON THE FEN EDGE – WITH SIR DAVID ATTENBRADLEY

EPISODE 1: I Heard a Murmur
EPISODE 2: Goldfinch Dynasty
EPISODE 3: Young People’s Beat Combo
EPISODE 4: The Cumulus Dynasty