Bridge – Grantham Ecology

Ferns

February 17, 2020Grantham EcologyLeave a comment

I have been writing a short piece in the Grantham Canal Society newsletter each month for the last three years – I thought it would be fun to share these little snippets on here! If you would like to subscribe to the digital newsletter which drops into your inbox once a month, or look at older issues, visit their website here:

February 2018 – Ferns

At a time of year when many wild plants have lost their green leaves, ferns can still be found brightening up bare walls. Those you are most likely to spot along the Canal are perhaps the Aspleniaceae, known by the common collective name of ‘spleenworts’. These species often grow in cracks in walls, where they find small patches of soil, and they like moist and shady conditions. These factors together make some of the walls along the canal, particularly around the locks, ideal habitats.

One of the most common and easily recognisable is the hart’s tongue fern – this is quite distinctive in that it is the only fern you’ll come across which has undivided leaves, looking more like a ‘normal’ plant but given away by its glossy leaves with spores dotting the undersides.

Another common species is the maidenhair spleenwort, which has a glossy, dark frond stalk and neat green leaflets arrayed on either side. Black spleenwort too is a common wall resident which looks more like fronds of your ‘typical’ fern or bracken.

These ferns are different to most of the other plants you will see along the canal – they neither flower nor produce seed but instead reproduce by means of spores which are lined beneath the leaves. The name ‘wort’ after a plant usually means that it was a food, or used medicinally. It is thought that the name spleenwort derives from folk beliefs that the plants were useful in curing afflictions of this organ!

maidenhair_spleenwort_image — Maidenhair Spleenwort – *Asplenium trichomanes*

Kingfishers

February 7, 2020Grantham EcologyLeave a comment

February 2017 – Kingfishers

If the weather is mild, then February is the month in which kingfishers will begin their courtship. Kingfishers lead a solitary existence in the winter – catching their prey can be hard as high water, poor visibility and the tendency of fish to move into deeper water all make fishing difficult. For this reason, a kingfisher will hold their own territory, often including waters not frequented in the summer, in order to maximise their chances of survival.

Once the first signs of spring begin to appear, pairs will court and share a territory once more, ready for the breeding season ahead. Kingfishers typically excavate nest tunnels in vertical banks, digging back 60-90cm and laying a clutch of eggs at the end. Through the summer, the pair can raise 2-3 brooks in quick succession, spending little time with the young once they have fledged in their haste to start the next clutch.

February and March are excellent times to spot kingfishers along the canal – the process of forming pairs and negotiating territories makes them active and vocal. All this whilst the leaves are yet to burst on the trees makes it easy to see that flash of electric blue zipping low along the water. If you’re trying to spot them on the banks, look on overhanging branches and think of their orange-brown chests as well as the typical blue of the backs – if they are facing towards you then this is what you need your eye in for!

kingfisher

Long tailed tits

January 14, 2020Grantham EcologyLeave a comment

January 2018 – Long tailed tits

A walk down the towpath in January is likely to be accompanied by the flutter of wings and warning calls as birds forage in the path-side hedgerows. One of the smallest species in the UK is likely to be among them, but far from being discreet they make their presence disproportionately known as they forage.

Long tailed tits, weighing just 9g, are highly social birds – they move through the landscape in flocks of closely related individuals, maintaining a shrill ‘si-si-si’ call-and-response as individuals keep in touch. Their aim, at this time of year especially, is to forage for enough high-value food to keep their tiny bodies warm enough to survive. They seek invertebrate prey by preference, capitalising on their low weight to pick food such as moth eggs as well as other invertebrates from the higher reaches of twigs and leaves which their heavier counterparts are unable to reach.

At night, the flock remains together, nestling down in a shrub or tree to form a dense ball with just their tails sticking out. As spring marches on, they will be building their tiny nests out of moss, lichen and spiders webs, lined with feathers. Interestingly, they are also social at nesting time – they will try to pair up and nest on their own but if unsuccessful, they will help at the nest of a close relative.

Listen out as you walk this winter – the distinctive call will alert you to the presence of these charming little ‘flying teaspoons’!

long-tailed tit.jpg — Long tailed tit on hawthorn – image kindly provided by Ryan Clark

Fieldfares

January 11, 2020Grantham EcologyLeave a comment

January 2016 – Fieldfares

Fieldfares and redwings are two thrush species which arrive in the UK for the winter each year, having spent the summer in their breeding grounds in Central Europe. The UK has had unusually mild conditions this year which has led to lower numbers than usual, but October and November still saw a good influx.

The Grantham Canal is always a reliable place to find chattering flocks of fieldfares which work their way along the hedgerows in search of the dogrose hips, hawthorn haws and blackthorn sloes, as well as the less obvious ivy berries which form a vital part of their diet in January and February when the best of the berries have been stripped. Their diet also includes insects, fruits and grains.

They are often quite cautious of human presence and their distinctive flight-call – a harsh “tsak tsak tsuk” – will often signal them moving ahead of you along the towpath.

Fieldfares and redwings often fly in mixed flocks but are easily told apart. Redwings are a rich warm brown with rusty-red underwings – similar in size to a song thrush – with a bold white line across the eyebrow. Fieldfares have more white/grey colour about their bodies and are slightly larger – similar in size to a blackbird. They lack the bold red underwing and the black supercilium which distinguish the redwing.

Both of these winter thrushes tend to stay with us through until April or early May when they head back to their breeding territories in warmer climes.

Fieldfare feeding on cotoneaster berry — Fieldfare feeding on cotoneaster berries