Archive for November, 2008

Early birds on Montjuic

Written by Lucy Brzoska

Remains of last night’s storm were still strewn across the eastern sky this morning. But the sun struggled free just as I reached the castle and it turned into a cold but clear day.

Too early for tourists, the castle was alive with birds, who find unexpected sources of water to drink and bathe in. A leaking waterpipe has created a long damp streak on the wall, like a banner of blue silk unfurled from the ramparts, capturing the vividness of the sky. There was a constant movement of visitors clinging to the wet stones. Black redstarts, which congregate in Barcelona for the winter, flurried to and fro, chasing each other in between sips. A handsome Great tit stopped by for a while, waistcoat matching the yellow poplar leaves. A lilting flock of goldfinches arrived, sweetly calling. The House sparrows, residents of the castle walls, had their turn, as did serins, a couple of Coal tits and a Tree creeper.

Round the corner, water has collected in an old stone gutter, to which someone once hastily attached a plastic pipe. A Blue rock thrush (Monticola solitarius) disappeared inside, emerging ruffled and damp. It dried off on the end of a canon.

This port-facing side of the castle is a haven in winter, secure from the north and westerly winds. The walls act like a storage heater, absorbing the sun all day. Sweet alyssum (Lobularia maritima) has spread unchecked on the grassy slopes, its fragrance living up to its name. A faded, threadbare Red admiral sunbathed on the wall. High up near the battlements, a Painted lady (Vanessa cardui) spread its wings on a plant rooted between two stones. Crag martins turned circles over the dazzling sea, over the castle and the half-bare fig tree. They only come in winter, but their leisurely swoops remind you of summer.

Cattle Egret in the Park

Written by Lucy Brzoska

An unusual visitor came to the park this week. While people lolled on the grass, kissing, reading and eating lunch, it quietly decimated the park’s lizard population.

Cattle egrets (Bubulcus ibis) breed in Barcelona zoo within the Grey heron colony. Unlike their bigger relatives, they are mainly land foragers and can usually be seen in the fields around the Llobregat Delta. Their adaptability to man-altered habitats is one of the reasons for the Cattle egret’s spectacular worldwide expansion over the last century (first pair bred in UK this year).

The opportunism of the egret in the park was richly rewarded. It stalked the ivy-covered ground, alert for rustling movements. Whenever potential prey was spotted, its neck would start wobbling. The undulation would travel back in waves, till even its tail was shaking. Its head, however, remained quite still. The sinuous movements seemed to be a way of warming up for the final pounce, which was nearly always successful.

The egret’s bill was an efficient pincer, applied with masterful technique. Each lizard was grabbed firmly by the body, away from the detachable tail. Sometimes the helpless lizards would wrap their tails around the egret’s bill, as if desperately trying to bind it. But struggling was useless. Inevitably they would be swallowed head-first, to join the ever-growing pile in the egret’s powerful digestive system.

On a short break, it stopped to preen, and caught a couple of flies, particularly annoying at this time of year. It was a reminder why Cattle egrets are valued by ranchers as an alternative to pesticides. They are often to be seen delicately picking bugs off animals’ backs. But the egret in the park soon went back to its more solid menu, swallowing reptile after reptile.

I began to worry about the park’s lizards, (mainly Podarcis hispanica), who normally enjoy a placid predator-free existence. But later I read about a study of an island population of lizards – the park is like an island in the city, after all – which involved unleashing an alien predator and observing the effect on the resident reptiles. The population was badly hit initially, but the species triumphed, exhibiting longer legs at first (better to run with) and then shorter legs (more useful when they took to the trees). An example of rapid evolutionary resilience.

The Cattle egret returned to hunting, but I’d had enough of observing. My lunch-break was nearly over, and I was starving.

Magpie Inkcap – Coprinus picaceus

I found these Magpie Inkcaps (Coprinus picaceus) in a dark damp corner of Collserola, growing among brambles. When fresh, their glistening caps are cylindrical and covered in tattered veil remnants.

As the gills liquify, the cap shrinks and flattens. Its brim rolls up and drips an inky substance. This allows all the spores to get their turn at maximum exposure, so they can be carried away by air currents.

Spores dispersed, the inkcap collapses, dissolved like the Wicked Witch of the West.

The Red Squirrels of Pedralbes

Written by Lucy Brzoska

The red squirrels (Sciurus vulgaris) of Palau de Pedralbes park stream along the branches unobserved, and build their dreys out of sight in the towering Aleppo pines, somewhere among the parakeet nests.

But sometimes they come to ground, especially in the afternoon when the army of gardeners have gone home and stopped their pruning, spraying and sweeping. Tails undulate in the grass like plumes as squirrels forage. Litter bins are investigated too, though at the moment there are plenty of seeds and nuts to gather.

Red squirrels vary in colour: those in the park tend to be a russet-brown, set off by white breasts, and black tails. At the moment their pelts are particularly lustrous, topped off by lavish ear tufts, their winter adornment.

When two squirrels meet, a helter-skelter pursuit often ensues. They scrabble noisily round and around the tree trunks, loosening a shower of bark debris. Spread eagled on opposite sides of the tree, they await each other’s next move. When one’s nerve breaks, the manic chasing resumes.

This ensures they’ll be fit for next spring, when the females go on heat and lengthy chasing begins in earnest, a prelude to mating. If climate and food supplies permit, which is surely the case in this Barcelona park, the females go on heat twice a year: between January and April, and then again between the end of May and August.

Red squirrels seem weightless as they skim through fragile canopies: the larger males reach a mere 350 grams. Other interesting anatomical features of squirrels include double-jointed ankles and long claws, permitting secure vertical descents. Like all rodents, their chiselled incisors never stop growing – about 15cm in a year. This red squirrel looks set to wear them down a little on a hard green pine cone.