Seasonal Update (January 2022)

Happy New Year from Wildlife Online. - Credit: Marc Baldwin

Welcome to 2022. I hope you had a relaxing and enjoyable festive break, and I'd like to take this opportunity to wish all my readers and their families a very Happy New Year.

December started chilly, interrupted by Storm Barra, which brought strong winds and heavy rain on Tuesday and Wednesday of the second week. Ireland and western Scotland were worst hit, with Mace Head Atmospheric Research Station on Ireland's west coast seeing winds gusting to 83 mph (133 kmph) and sustained wind speeds of 58 mph (94 kmph), but all areas saw rain and wind.

Things warmed up into the second weekend and week three was unseasonably mild for most of England, with daytime highs in the south-west of 14C (57F) and temperatures falling to only 10 or 11C (51F) overnight. Western Scotland saw more rain and strong winds at the start of the third week, bringing highs of 13C (55F) in The Highlands. Things started to cool down towards the end of the week for Scotland and northern England, but most of Ireland, Wales, the Midlands and southern England remained above average into the third weekend.

A brief dip to the seasonal average started Christmas week before another large low pushed into the south and west from the Atlantic, bringing very mild and wet weather for the Christmas weekend for southern England, while much of the Midlands, Wales, northern England and Scotland saw cold, bright weather and a white Christmas.

A Mercator map showing the temperature anomaly across the globe over the past decade (2011-2021) relative to a baseline of 1951-1980. We often complain about the record mild or cold months being "just weather", which they are, but as the globe continues to warm these freak hot and cold periods are becoming increasingly common, making conditions more unpredictable than they were 60 years ago. - Credit: NASA - GISS Surface Temperature Analysis

Things remained unsettled between Christmas and New Year but exceptionally mild as high pressure became ensconced over France, drawing up warm air from the Azores and Madeira and giving us temperatures of up to 15C (59F) quite widely in the south and 17C (63F) in Norwich; ordinarily, we'd expect daytime highs of about 7C (45F) in late December, although this was still below the national record for December of 18.7C (65.7F). Things remained mild, unsettled and gloomy to start 2022. Indeed, although we're waiting for official figures, this looks to be the least sunny December on record by some margin. Certainly, one weather station in London recorded only 15 hours of sunshine last month, the average being about 50.

Outside of the UK, parts of western Europe saw some very cold weather last month, particularly the Alpine areas and Scandinavia, while the Black Sea and Caucasus area saw an incredibly warm December, frequently registering temperatures 25C (77F) and even many tropical nights— on 12th December the Turkish Black Sea coastal town of Inebolu (Kastamonu province) rose to a summer like 27C (81F).

Parts of the US also saw a third record-breaking heatwave, with 31C (88F) recorded in Florida and Texas, 27C (81F) in Mississippi and 26C (79F) in Alabama. The first day of winter in California saw the mercury rising to 33C (92F) at Chino, just east of Los Angeles, but the month ended quite differently. Over the Christmas weekend southern California was hit by torrential rain that caused flooding and power outages - San Marcos Pass in Santa Barbara saw 4.5 cm (1.8 in) in 24 hours. On Boxing Day, avalanche warnings were issued for parts of Nevada, Utah, Idaho, Montana, Colorado and California after nearly 30cm (12 in.) of snow fell in only 24 hours on Christmas afternoon, while Montana residents were warned of -48C (-54F) wind chill.

With the unseasonably mild weather most of us in the UK and western Europe are experiencing at the moment, many will be tempted into the garden for a tidy-up. This unassuming pile of leaves is actually a hedgehog nest, so please be vigilant and careful when working in the garden to make sure you don't accidentally disturb a sleeping or hibernating hog. - Credit: Marc Baldwin

Last month, the National Weather Service issued a blizzard warning for Hawaii, ahead of 30 cm (12 inches) of snowfall and 100mph (161 kmph) winds on the Big Island summits, which are relatively uncommon for Hawaii. Most of the lower 48 states recorded below average snowfall in November and in Colorado, a new record was set for the latest start to the winter snowfall, Denver entering December with no measurable snow; this hasn't happened since records began in 1882.

Website news

A few minor updates have been made to the hedgehog and red fox sections and I've been continuing to work on the Chinese water deer article, with part four passed to the proof readers just after Christmas. I have also uploaded some new sections of the profile, with the coverage of tusks now being online.

In the news

A few of the news stories that caught my attention this month include the UK's first dormouse bridge, ducks who mimic what they hear as hatchlings and polar bears under pressure.

Octopus tentacles hanging in a harbour in Greece. Octopus is a popular dish in the USA and Asia, prompting a drive to farm these cephalopods. - Credit: gwendolen (CC BY-NC 2.0)
  • Cephalopod controversy. The world's first octopus farm is being built in Spain to commercially rear these animals for use in the restaurant trade. Octopus is an increasingly popular dish in the USA and Asia, and there has long been a race to understand how to rear the cephalopods in captivity. Scientists and conservationists have expressed their dismay, however, pointing out the ethical issues with farming such intelligent and sentient animals for food.
  • Musk mimic. Adult musk ducks (Biziura lobata) raised in captivity can mimic the sounds they heard as hatchlings, including a pony snorting, a door slamming, a man coughing and even what researchers think was probably a former caretaker's catchphrase, 'You bloody fool!'
  • Rodent runway. Conservationists hope that a square metal tube, which is set to become the UK's first dormouse bridge across a railway line in Britain, will connect two new dormouse populations in Morecambe Bay when it's fitted across the Furness line in Lancashire next summer.
  • Polar pressure. Researchers say that the extreme lack of sea ice in Hudson Bay should serve as “a wake-up call” to the risk that climate change poses to polar bears (Ursus maritimus). Ice normally starts building in the bay during November, but this year it has remained almost entirely ice-free as temperatures have remained 6C (11F) above average. In an average year, 70-80% of the bay is ice-covered by early December, but this year the figure was only 13%.
  • Fossil find. A 70-million-year-old oviraptorosaur egg has been found in the basement of the Yingliang Stone Natural History Museum in China containing the most well-preserved dinosaur embryo known to science.
  • Hedgehog high. After several hedgehogs became stuck in a boundary fence at Lanark station in the central Lowlands of Scotland, Network Rail have agreed to cut hedgehog highways in the boundaries of the station. Network Rail announced that they now plan to add these highways to other railway stations.

Discoveries of the Month

Gimme shelter: fox and badger dens as key overwintering sites for insects

When winter bites, most of we humans enjoy a brisk walk in the cold before returning to the warmth of centrally heated homes for a hot drink and a mince pie. For us, the cold of a “proper” winter is a livener, but for most other species it's a trial to be weathered.

One of several entrances to a badger sett in Sussex. Setts, dens and earths provide shelter for more than just the animals that create them. - Credit: Marc Baldwin

Typically, species have a couple of options for dealing with winter - opt out, or stick it out. While some bird species migrate and our smaller mammals hibernate, most can tough it out. They can achieve this for three main reasons: there's something around they can eat (even if it's just peanuts and fat balls put out by humans); they have grown an insulative winter coat/plumage to help them stave off hypothermia during the long winter nights; and most critically of all, they're endothermic, so they can generate the heat needed to accomplish all their biochemistry from within. For those species unable to grow insulation and that need a helping hand from the weather to generate sufficient heat for their daily activities, very cold weather needs to be endured.

A big part of being able to survive the winter is a safe place to shelter from the elements. For hairless primates such as ourselves, it's our houses, but a lot of species create their own homes to shelter them from the worst of the elements. Many species will take advantage of the hard work of others and use their homesteads for shelter—these, indeed any animal that exploits the living space of another, are known as inquiline species and include many insects.

To understand how insects utilised infrequently visited or abandoned carnivore burrows in a forest around the city of Poznań in western Poland, a team of scientists led by Łucasz Mycsko at the Poznań University of Life Sciences set pipe traps in fox and badger dens to collect insect visitors. During their trapping session, the researchers collected 4,440 individual invertebrates, representing at least 91 species of insect, arachnid (spiders and harvestmen), myriapod (centipedes and millipedes), isopod (woodlice) and mollusc (slugs and snails). Mosquitoes were by far the most abundant, accounting for nearly 80% of trapped inverts, followed by beetles (10%), flies (6%) and even two species of butterfly. Writing in Ecological Entomology, Myczko and his team conclude:

“... we may suppose that burrows of medium-sized carnivores are convenient shelters or breeding places for many more species than have been reported elsewhere. Therefore, burrows dug by red foxes and badgers may play an important and crucial role as focal places of diversity for wintering fauna.”

Reference: Myczko, L. et al. (2021). Where to overwinter: burrows of medium-sized carnivores as winter places for invertebrates in temperate environment. Ecol. Entomol. 46(5): 1177-1184. doi: 10.1111/een.13062.

Citizen science sheds light on hedgehog habitat suitability

As the human population continues to grow, urban sprawl poses a real threat to wildlife across the globe. Indeed, according to a recent report in Nature Sustainability, we're “living in the period of fastest urban growth in human history, with more than 2 billion additional people expected in cities by 2030 - a pace that is the equivalent to building a city the size of New York City every 6 weeks”. A big part of reducing the impact our sprawling cities have on wildlife is understanding how species respond to our building activities.

New citizen science data from London boroughs suggests that urban greenspaces, such as parkland and allotments, are increasingly important habitat for hedgehogs in our towns and cities. - Credit: Jim (CC BY-NC 2.0)

In the past decade or so, the idea that members of the public can contribute valuable data to help scientists get a handle on what's happening with a species' distribution and abundance has become galvanised. We call this citizen science, and the growing pool of data is being used by researchers and conservationists to fill in gaps in our natural history understanding of a variety of species from around the world. Recently, a team of scientists at the Zoological Society of London employed data submitted during wildlife surveys to the People's Trust for Endangered Species, GiGL and the NBN Gateway to get a city-wide perspective of the habitat relationships of hedgehogs in urban areas, and used them to predict habitat suitability in Greater London.

The results of the ZSL's analysis, currently in press with Mammal Review, show that gardens, allotments, parks and playing fields were the areas where hedgehogs were most likely to be encountered. Private gardens made the greatest contribution to this urban green space, underscoring their importance as core habitat for hedgehogs. Allotments were more likely to host hedgehogs than parks, which the authors consider may reflect the tendency of the latter to be managed for short grass and higher tree densities. Interestingly, despite earlier studies having found to be woodland important habitat for hedgehogs in France, and its presence to have increased hedgehog encounters in nearby gardens, this dataset showed woodland as the only green space to negatively affect hedgehog presence.

Of particular note among the findings of this study was the influence that human presence had on hedgehogs. We know from previous studies that large public events, such as music festivals, can cause hedgehogs to vacate an area and, in Bristol, a study in 2010 found hedgehogs became more active after midnight in the city, we think to avoid the worst of the pedestrian and vehicle activity. Similarly, this dataset revealed that human density was the second most important variable in determining whether hedgehogs were likely to be recorded. Hedgehog occurrence was significantly reduced where the density of people exceeded 2,262 per sq-km (5,881 per sq-mi.). Badger presence also had a negative impact. In their conclusion, the researchers explain:

This study finds high variability in habitat suitability for hedgehogs within Greater London and suggests that loss of habitats such as gardens, parks, and allotments, and disturbance associated with high human populations may be limiting their presence. As Greater London is predicted to expand and become increasingly densely populated by humans in future, this research highlights the importance of maintaining habitat features such as gardens, allotments, and public parks to allow the hedgehog to persist in this urban landscape.”

Most of us enjoy seeing hedgehogs in our garden, but to ensure they prosper we need to manage these "wild spaces" sensitively. - Credit: Mark Houghton

Reference: Turner, J. et al. (2022). Using citizen science to understand and map habitat suitability for a synurbic mammal in an urban landscape: the hedgehog Erinaceus europaeus. Mamm. Rev. In Press. doi: 10.1111/mam.12278.

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