Gray skies and bare tree trunks these months seem to underline a persistent myth: winter is a dead season. Everything in nature is awaiting spring or is in a state of advanced rot. At least, that’s how it looks.
Yet many moss plants have their best time during the winter months, polders and nature reserves are filled with thousands of wintering birds and an astonishing number of flower plants are already stirring before the start of the new year. What natural beauty makes it worth going out now? An overview.
The botanical bloomers
Even in winter you can still encounter flowering plants. Even before New Year’s Eve you can look forward to the first blooming hazels (Corylus avellana) and alder (Alnus), whose catkins bloom on average earlier and earlier over the years. And annual varieties in particular make a third attempt at flowering in mild winters.
The Floron Foundation, which researches Dutch flora, organizes from December 25 to January 3 the ‘end of year plant hunt’. The idea is simple: take a short walk outside during this period, write down all the flowering plants you see and pass them on digitally. In 2023, more than five hundred flowering species were found during the count, roughly a third of the native Dutch flora. The top three consisted of the small groundsel (Senecio vulgaris), annual meadow grass (Poa annua) and first and foremost the Dutch national flower, the daisy (Bellis perennis), whose scientific name aptly translates as ‘everlasting beauty’.
These are all varieties that can now bloom due to the mild winters. The Netherlands only has a few real winter flowering plants, such as the yellow dogwood (Cornus mas) and the snowdrop (Galanthus nivalis). Estates and historic city parks turn yellow in January with the sunny flowers of the winter aconite (Eranthis hyemalis). This plant is related to the glacier buttercup (Ranunculus glacialis), the highest flowering plant in the Alps (above four thousand meters). The winter aconite chooses to bloom in the coldest months of the year, January and February, and then looks most like a miniature palm tree with a flower on top.
The large yellow flowers of the winter aconite face the sun
For flowering plants in January, it is essential to catch as much light as possible and to stand out for pollinators. During this time, almost only bumblebee queens fly around looking for food on sunny winter days. The large yellow flowers of the winter aconite only unfold in such weather and face the sun. A thermal camera can clearly see how the saucer shape of the flowers retains heat. The warmth and the flower size ensure that the flowers stand out for bumblebees.
From February it is time for the little early ones (Draba verna). Some flower plants use winter as a time to save for the new year, during which a leaf rosette is visible. The little one also saves energy with small rosettes. It grows between the joints of the pavement and shows its white flowers at the very beginning of the year.
The cool cold blooded ones
The snowflea (Boreus hyemalis) is an exceptional insect. While other insects have limited movement at low temperatures because they are cold-blooded, the monstrous-looking snow flea crawls around in the winter months to look for a mate. The eggs develop underground, where the larvae feed on moss remains. The adult animals are also called snow jumpers, due to their tendency to actively jump around even on snow.
The cells of the snow flea contain proteins that lower the freezing point of the cell fluid. This explains the trick of the snow flea, whose activity peaks in winter – when spring arrives there is no trace of the animal left. The insect still occurs locally on sand drifts with lots of maidenhair, but is considered rare nationally.
In peak years there can be a huge crowd of fluttering males
Winter butterflies still fly around well into the December nights. They exhibit all kinds of wing pattern variations within the same species. The Netherlands has three: the large, small and birch winter butterfly. The females are never found flying, they are completely wingless. At a glance, they look more like a spider than a moth. The females often sit motionless on the bark of trees. In late fall and early winter, they release sex pheromones at night: chemicals that attract males. That explains why the females only have wing stubs: the males fly towards them. In peak years there can be a huge crowd of fluttering males around tree trunks with a female on top. In the light of headlights and lampposts, the butterflies are clearly visible on nights when the temperature remains just above zero. After successful mating, the female lays eggs on suitable host plants, such as the pedunculate oak. The caterpillars overwinter as eggs and hatch in the spring.
Dancing geese
In addition to all the little things that grow and crawl, the Dutch winter is also the scene of something much bigger. Millions of birds camp in the Netherlands from areas further north. Anyone who visits the plains of the Oostvaardersplassen in winter will hear a cacophony of thousands of geese feeding on grass. Flocks of these winter visitors regularly fly up, often to escape predators, and perform impressive dancing aerial scenes. Some of these winter geese are the barnacle goose (Branta leucopsis), brent goose (B. bernicla), greater Canada goose (B. canadensis) and white-fronted goose (B. albifrans).
Hikers can see small white balls on the top of trees and posts in the winter heathlands and dunes. These are great shrikes, which winter here. Great Gray Shrikes are famous for being somewhat sinister birds, due to their ability to impale prey on barbed wire or thorn bushes and store them there as a snack for later.
The sinister gray shrike can be seen on heathlands
Other birds are here all year round, but only become noticeable when they can no longer hide between plants. Kingfishers display themselves beautifully on twigs above water from where they can dive for fish. Despite its name, ice is actually disastrous for the kingfisher. When water freezes, they can no longer hunt and quickly die of starvation. As a result of the increasingly mild winters, kingfishers can now be seen (and heard) more often.
Two birds whose names do match their behavior are the snow bunting and the ice bunting (Plectrophenax nivalis and Calcarius lapponicus). During the winter, these northern birds can mainly be seen along the coastal strip. They can usually be spotted calling in small groups flying overhead.
The Sovon Foundation also conducts international research into wintering water birds, with the help of volunteers. During this midwinter count, bird watchers set out simultaneously in large parts of Asia, Africa and Europe to monitor wintering water birds.
For those who want to spend time in nature in the winter, birds are the solution. Whether it concerns slumbering bitterns, camouflaged among the reeds, or groups of perfectly white egrets that stand motionless together like nymphs after snowfall, there is plenty to see for birders in the Netherlands, even in the cold months.
Growing growths
It is also worth taking a closer look at the bare branches of trees, such as those of the pedunculate oak. There are sporadic growths on the buds and twigs, and on the last dry, clinging leaves. Some of these tumors are ball-shaped, others form flat discs or take on even crazier shapes. These are so-called galls, which are often formed by gall wasps. These tiny wasps grow to only a few millimeters in size and often fly only short distances.
On host plants, gall wasps lay their eggs in specific tissues using an ovipositor. These can be flowers, buds, twigs or fruits, where many gall wasp species limit themselves to one specific tissue. After egg deposition, the young larvae release substances that manipulate the cells of the host plant, causing the surrounding tissue to grow into a gall. This has two advantages: the larvae are protected from predators, and they eat the plant tissue.
Perhaps the most impressive is the gall of the coral gall wasp
Each gall wasp species creates its own specific form of gall. An impressive gall in winter on pedunculate oaks is that of the ram’s horn gall wasp (Andricus aries), which forms horn-like outgrowths from the buds. When the larvae mature, they make a hole in the gall and crawl to freedom.
Even though the galls are in fact tumors, they can sometimes look very nice. The satin button gall wasp (Neuroterus numismalis) for example, makes beautiful brown knots on the underside of oak leaves and is common.
Perhaps the most impressive of all, and one that is at the same time very rare, is the gall of the coral gall wasp (Andricus lucidus), which produces complex growths on oak twigs that strongly resemble coral.