The term ‘ecology’ is commonly used to discuss the relationships between organisms and their environments; it is about considering all the relationships as well as the character of the interactions between organisms and their environments. I take ‘organisms’ to mean human and non-human, thus the ecology is about interactions – about the way organisms can and do live and the processes that exist to support life and lifestyles.
In a walk from Victoria Bridge, Shipley westwards to Hirst Lock along the Leeds-Liverpool canal I recorded an observational ecology. This was part of the route recommended for the Community Connections Circular Stroll on 10th July 2015 which included a ‘Meadow Meander’ and BBQ at the Coach Road community, a visit to the Triangle, Shipley and the ‘Wide Angle’ activities at the Kirkgate Centre.
An Observational Canal Ecology:
Canals are created and maintained by humans. Non-human species readily colonise the spaces in and around the water bodies. The water in canals is generally fairly static and most canals do not have the naturally sloping edges associated with other more ‘natural’ water bodies such as un-canalised rivers, ponds and streams. This tends to limit their habitat potential as some of the richest habitats associated with water tend to be found on the edges where land and water meet.
What is immediately apparent when
walking west along the canalside from Victoria Bridge, Shipley is the
narrowness of the ‘green’ corridor, with buildings often placed right up
against the waterside. A boy and his
father are fishing from the towpath. The
day is warm, the towpath here is tarmacked, the grasses in the cracks are dried
and dead – either from herbicide or lack of moisture. The water is dark brown and further along
there are spearheaded floating water weed leaves. Many generalist plant species inhabit the
narrow verges along the path and the cracks and crannies of the canal walls.
Generalist or pioneer plant species are those that can adapt to a range of
situations, particularly inhospitable soils or dryness, and tend to have seeds
that are easily spread. Many urban species
– both plants and animals – can be classed as ‘generalist’. Some years ago I did a study of the habit of
the Raccoon (Procyon lotor) in
Cambridge, Boston. This animal is sometimes
seen as the equivalent of our urban Red Fox (Vulpes vulpes) in terms of its marvellous ability to adapt to the
city habitat. The raccoon finds plenty
of places to live in old urban trees and the basements of the clapboard houses.
Like the fox, it is a master of finding scraps of food from our cast-offs and
using fences and other structures to get about the city. Canal corridors, like river, road and rail
corridors can provide good opportunities for mobile species like foxes to travel
in and out of the city, but the usefulness of the corridor depends on the
permeability of the boundaries – or the opportunities to move off the canal
corridor into adjacent woods, fields and gardens etc - and whether these are
good places for foraging and living.
Back to the canal, and another generalist species, the Feral Pigeon (Columba livia), has found a perfect nesting site under a bridge. A number of birds are here, cooing and pouting. Twin juveniles peer down at me uncertainly. Many urban pigeons suffer persecution from humans. However pigeons are intelligent and they have a very long history of close interaction with humans for food, as sacred symbols, messengers, ornaments and many other roles. The urban pigeon is clearly identified with the character and ecology of urban spaces (remember Mary Poppins and Trafalgar Square?).
Further on there is a luxuriance of pioneer species on a piece of disused ground on the south side of the canal. Clinging to the canal walls are ferns and Rosebay Willowherb (Chamerion angustifolium). Willowherb is a familiar sight throughout the country along verges, and particularly along railways. Plant seeds hitchhike onto vehicles of all sorts as well as birds and animals in order to maximize their potential for dispersal. Sticky seeds such as those of Cleavers (Galium aparine) are particularly good for clinging to the long hair on horses legs. Pioneer trees and plants will, given the chance, find suitable cracks to grow in buildings which act like ‘cliffs’. The seed is probably carried on the feet of birds. Many plant species rely on an animal or plant host for distribution of its seed. Mistletoe (Viscum album), which I remember growing in profusion on old orchard trees in the Herefordshire of my childhood, is one of the most ingenious, with its extraordinarily glutinous berries able to cling to the feet and beaks of birds. Of course canal water is an effective transporter of seed as well as logs and human rubbish. The Sycamore (Acer pseudoplatanus) seeds bobbing on the surface of the water have ‘wings’ that act like sails being blown away by the west wind towards Bingley. Invasive and unwanted species carried around the world in the water used for ship ballast is a particular problem today. Presumably over the years the canal boat cargoes, the water fowl, horses and the barge men and women have all played a part in spreading various plant and animal species through the canal networks around the country.
As I move on the grassy verge beside the canal is greener and there are many people of all shapes, sizes and ages enjoying the canal side route. There are many cyclists and there is an easy giving of way between walkers and cyclists on the path. The cyclist species range from small children and parents with shopping swinging from the handlebars, to long-distance lycra-clad cyclists with bedrolls. This route is part of the Airedale Greenway which is a combined walking and cycling route connecting Keighley, Bingley, Saltaire and Shipley with the Sustrans Route 696 of the National Cycle network, which follows the Leeds and Liverpool Canal. This probably explains its popularity. The surface is well-maintained and there is plenty of room for all despite the crowds. There are lots of dog-walkers. While dogs have a symbiotic relationship with humans – they provide a good reason to go for a walk and thus can be the catalyst for more healthy lifestyles - they can be very destructive to habitats and disrupt wildlife routes. On the grassy verge of the towpath there is evidence of both dog and goose deposited; the presence of geese suggest that at least this bird species is not too worried about the presence of dogs!
A Swift (Apus apus) dips into the water for a drink. This sleek and beautiful bird is now on the ‘Amber List’ because the numbers of swifts have declined dramatically in the past 10 years. I can hear young Great Tits (Parus major) making a racket in the vegetation. There are surprisingly few insects around, but perhaps this is because it is quite windy. There are a few bumble bees (Bombus spp.) on the bramble flowers (Rubus spp.), yet other pioneer plant, which is blurring the boundary between verge and water. A dead fish is held belly-up amongst the prickly net of the bramble stems. All along this canal there are tiddler fish rising to the surface, but this corpse is by far the biggest fish I’ve seen. Feathers litter the grass. Bindweed (Convolvulus spp.) is trying hard to obscure the ‘keep out’ signs and railings around the industrial buildings, which turn their backs on the canal. The rubbish in the ditch next to the railings indicates a seamier side to the human ecology of this route. Stinging Nettles (Urtica dioica) grow in profusion. These are excellent indicators of human activity – particularly useful to identify former rubbish tips or settlement sites in the landscape where actual buildings cannot be seen. Nettle soup – a traditional recipe – has come back into fashion. Quite a meal could be foraged from this canal side; the Elderflowers (Sambucus nigra) would make a wonderful sweet syrup, or delicately sparkling ‘champagne’, the willowherb can be used to flavour ice cream and many ‘weed’ (pioneer) species can be used in salads.
Outside Salt’s Mill at Saltaire, large Yorkstone slabs and a fairly new slotted drainage system suggest that this part of the path may have had drainage problems in the past. Opposite the mill sapling trees have found a roothold between the foot of a large building and the canal edge. A number of these trees look like Elm (Ulmus spp.), possibly the Wych Elm (Ulmus glabra) which often tends to spread along waterways. Although Yorkshire, like other parts of the country, lost many fantastic mature Elm specimens to Dutch Elm disease in the 1970s and 1980s, everywhere here in the hedgerows and edges there are young trees. I remember walking from Helmsley to Rievaulx, North Yorks in the 1990s and marvelling at a mature clump of Elms that had survived in the middle of a field of corn. The shape of such specimens, once so familiar in the countryside, has now mostly disappeared.
There’s plenty of Ragwort (Senecio jacobaea) along the path verges This is only one of five ‘weeds’ covered by the Weeds Act 1959 because it is poisonous to horses and other grazing animals. However it is also good for insects and provides a beautiful splash of yellow colour next to the canal. At the entrance to Roberts Park the Greylag Geese (Anser anser) find refuge on the water or on the pasture on the north side away from the crowds. Greylags are wild geese, but they clearly like the opportunity for an easy feed from the young bread-providers here both on the canal and the riverside. One or two Canada Geese (Branta Canadensis) are also around. Not everyone is fond of geese in Roberts Park. But I wonder what percentage of people in the UK would remember ‘feeding the ducks’ in their childhood. Perhaps this is the earliest contact with both ‘wild’ life and water in the landscape for many.
The canal seems to widen a little, large once-pollarded Plane trees (Platanus × acerifolia) provide a light arching green tunnel; on the far bank other trees overhang the water. The path becomes a dry and dusty ashlar; the ‘fines’ providing a good smooth track for cycling. The far bank here is much more like a riverbank, with marginal species such as the Yellow Flag (Iris pseudacorus) and Meadowsweet (Filipendula ulmaria) growing where water and land meet. A pair of ducks bob around on the wash from a small boat. The land opens up on both sides, in character much more like a water meadow. This was obviously someone’s favourite spot; a nearby a Field Poppy (Papaver rhoeas) mirroring the sense I have of this particular place. I pause to consider how many people must have walked this same route and how the vegetation may have provided an indication of the changing ecologies of all the animal and bird species that inhabit this place, since the construction of the canal which took 46 years. This canal is the longest in Northern England (127 miles) and it passes through 91 locks.
At Hirst’s lock, a small boat is waiting while the gates are opened. At the top of the lock scum and iris corms float, caught by the barrier of the gates. Ferns and weed cling to the lock side – the plant-limpets of this freshwater world. As I turn off the towpath towards Coach Lane a Mute Swan (Cygnus olor) seems to be waiting for the lock gates to open. I wonder if it is moulting. In the estuary at Berwick–on-Tweed where I did a project long ago I remember being astonished by great flocks of moulting swans congregating in the harbour in a communal changing of cloths. This single swan seems to be accompanied only by a single small Mallard Duck (Anas platyrhynchos). People stop to watch the drama of the lock gates opening and the boat going through. The sign on the lamp post suggests that this has long been a place to go to for a nice day out. While canals lack the drama and textures of rivers their attraction perhaps lie in their tranquillity, and apparent constancy; the human control over the water environment which cannot be guaranteed on or around a river.
Airedale Greenway: http://www.airedalepartnership.org/pdf/Airedale%20Greenway%20Map.pdf
Canal and River Trust: https://canalrivertrust.org.uk/canals-and-rivers/leeds-liverpool-canal
Pennine Waterways: http://www.penninewaterways.co.uk/index.htm
Pigeon Control Resource Centre: http://www.pigeoncontrolresourcecentre.org/html/about-pigeons.html
RSPB Help the Swifts: http://www.rspb.org.uk/discoverandenjoynature/discoverandlearn/swifts/
Stanford, M. (2014) Canada Geese in Roberts Park, Telegaph & Argus, Wednesday 20 August 2014: see http://www.thetelegraphandargus.co.uk/news/11420357.VIDEO__Canada_geese_force_Saltaire_Cricket_Club_into_daily_clean_up_operation/?ref=rss0
Sustrans route 696: http://www.sustrans.org.uk/ncn/map/route/route-696