Archive for October, 2008

Snake in the Wall

Written by Lucy Brzoska

What drew my attention was the lizard dropping off the wall.

I was on the Camí del mar, a path that circles Montjuic castle and overlooks the sea, which on this misty, warm day merged seamlessly into the sky. People were walking, running or cycling. An old man sunning himself on a bench had brought along a goldfinch, which sang in its cage. The fig trees were still green, but their large leaves had stiffened and occasionally one came clattering down.

From a distance, the castle looks a warm sandy colour, but close up each of the stone bricks is unique, the faded red and yellow patterns sometimes erupting into psychedelic swirls. The quarries of Montjuic have yielded a lot of sandstone for the city’s buildings.

In places the stones have been crudely patched up with cement, but fortunately plenty of cracks and holes remain. There’s no shortage of nesting sites for House sparrows, or refuges for ants, woodlice and spiders. The south-facing slopes of Montjuic are a suntrap, and as the wall heats up, it begins to flicker with lizards.

Approaching the spot where the lizard had made a sudden dive, I noticed a Moorish gecko (Tarentola mauritanica, Salamanquesa común) clinging on near the entrance of a tiny cave. Another step and it withdrew inside.

But there was something far more dangerous than me only two stones away.

The snake, long and slim, lay apparently lifeless, draped on a narrow ledge. When you spot a snake, there’s a tingle of excitement and you hold your breath, almost with disbelief. It came to life and slid into a crevice, keeping watch from within. When I moved, it stretched out its head to keep track of my position.

I didn’t know it was a Montpellier snake ((Malpolon monspessulanus – culebra bastarda) till I got home and checked. The ones I’d seen before were adult, much larger and darker than this slender, well-camouflaged specimen. The unforgettable photograph on Iberianature left no doubt. I recognised the penetrating stare, tapering head and white stripes, like war-paint, below the eyes, although I don’t know if this young one was quite ready to tackle a sparrow yet.

There was a wall-full of prey there, but the Montjuic Montpellier snakes have a reputation for reaching a fiercesome size on a diet of rats.

Autumn Bugs: hide and seek

At the road side near Vallvidrera, a cellulose gymnast was swinging through the stems. If you’ve grown up thinking of Stick insects as exotic pets kept in glass containers, it’s a thrill to find them ranging free. They look fragile, but can re-grow a damaged limb after a moult.

Another plant imitator, the Praying mantis (Mantis religiosa), is quite visible in Collserola in October. Like Norma Desmond in Sunset Boulevard, this elegant specimen couldn’t take its eyes away from the camera.

The black spots, which look eerily like pupils, are an effect of light reflecting from the compound eyes. The mantis also has three “simple” eyes between the antennae that act as an auxilliary light metre. With its swivelling neck and stereoscopic vision, there’s not much that goes on unnoticed around a Praying mantis.

From camouflage to aposematism – currently every Wild carrot nest has a Striped shieldbug (Graphosoma lineatum) inside. Experiments have confirmed that the colouring of these bugs helps predators remember their bad taste. As if testing out the theory themselves, they are often in prominent positions on the top of plants.

Its vivid red and black colouring probably saved this Firebug (Pyrrhocoris apterus) in Palau de Pedralbes park. Climbing up the rocks, it stumbled onto a sunbathing Wall lizard. After assessing the situation, it hurriedly changed direction. The lizard watched, but made no move.

In search of Two-tailed Pashas and the Autumn Narcissus

Written by Lucy Brzoska

On a trip to the Mediterranean, far from their Cantabrian mountain homes, Lisa and Teresa ventured into the big city to meet up with the Iberianature Barcelona contingent. Nick and I then accompanied them for a tour of some of the natural spaces that sustain the metropolitan populace.

The Garraf is an antidote to claustrophobic canyons, which is how Barcelona’s streets sometimes feel. It’s an airy expanse of garrigue-covered hills, open to the shining sea. We didn’t have to go far to find the Two-tailed Pasha (Charaxes jasius), top on Lisa and Teresa’s list along with the Autumn narcissus (Narcissus serotinus). While the Pashas chased each other around the fig trees near the visitors’ centre, Lisa and Teresa stalked them with their cameras.

Meanwhile, Nick and I followed a signposted botanical route, an excellent way to learn some of the plant species typical of the area: Kermes oak, Prickly juniper, and cistus. Nick spotted a solitary white flower, fragile among all the tough leathery leaves and spines. It was photographed and duly forgotten. We also discovered that the Garraf strawberry trees (Arbutus unedo) produce some of the best arbutus cherries anywhere: sweet and acidic, unlike the bland fruit I’d tasted before. They clearly thrive on this sun-soaked limestone terrain.

The lonely white flower did turn out to be an Autumn narcissus, as was discovered much later in the car. It was too late to turn back, but Teresa forgave us and continued to share her extensive knowledge. So we were able to learn that the Tree heath (Erica arborea) familiar to everyone who walks in Collserola only grows in acidic soil, and here is replaced by the purple-flowering Mediterranean heath (Erica multiflora). An insect slipping its black segments across the fallen pine needles turned out to be a Glow worm larva (Lampyris noctiluca), with a voracious appetite for snails. A dirty clump of debris hanging on a guardrail was identified as the case of a Bagworm.

After some debate, we decided there was time for the Llobregat Delta. Back down at sea level and just after the turn-off for the reserve, something white caught our eye: an extensive patch of Autumn Narcissi.

After liberal applications of mosquito repellent and an osprey-sighting, we crossed the bridge into the reserve. Outside the hides, translucent herons fished in sparkling water, sandpipers bathed in the shallows, cattle egrets groomed the horses, kingfishers streaked here and there, and spoonbills tried to keep up with their restless spatula-shaped bills.

There was little time left, but Collserola could not be missed. Up by the Forat del Vent, suitably windy, a flock of Pekin robins (Leiothrix lutea) held our attention with their melodious Blackcap-like song. Unlike other exotic escapees that settle in more urban environments, these South Asian cage birds are breeding in woodlands. They’re being monitored but studies suggest their presence has so far had no harmful effect on the authoctonous species.

We’d run out of daylight. After dropping Nick and I off at the metro, Lisa and Teresa drove away for the next stage of their adventure.