Archive for June, 2008

Walking in the Serra de Montgrony

After weeks of rain, the forecast for last weekend was good, so I headed off to one of my favourite places in Catalunya, Montgrony, to do some walking. The hostal of Montgrony is perched on a boundary: below are the pre-Pyrenees, with steep wooded valleys and isolated masias, while above begin the Pyrenees proper, with mountains of up to 2000 metres.

I’m usually looking up at the sky and trees to see birds, but the displays of flowers were so stunning, my attention was constantly drawn to the ground. After a week of studying, I’ve finally identified most of the flowers, with help from Lisa. (I’ve also taken Lisa’s idea of putting the images on the gallery first.)

The high open pastures were particularly impressive: the predominant colour was yellow but there were also swathes of forget-me-nots, flax and red clover, and, with the occasional bright blue or purple gentian (Spring and Trumpet.) Best of all were the Wild tulips: tall, graceful and fragrant, waving in the breeze. There were also some mysterious dark red flowers that I discovered later were Black vanilla orchids (Lisa’s photo) – with a scent of vanilla – wish I’d smelled them! Around the rocks at the top were clusters of Hairy Androsace, or Rock Jasmine (maybe a better name).

I met people with bags crammed with Cama secs (Marasmius oreades), small mushrooms, whose Catalan name means Dry legs – perhaps because their stems are quite tough. There were hundreds still to be picked, and I took some home, being told they store well if you dry them.

When not marvelling at all this, I had time to look up and notice Griffon vultures, and a Short-toed Eagle passing by and some Wheatears on the rocky outcrops.

By the time I was heading back to Barcelona, spring had been overtaken by summer, cows were being led up to the high pasture and the sun was scorching.

Citadel of Herons

Packed tight between the mountains and the sea, Barcelona is a noisy, densely populated city. Any visitor who climbs Montjuic or Tibidabo for an overall view will immediately be struck by the absence of green space. The nearest most people have to a garden is a few plant pots on a balcony. Yet in the heart of this intensely urban environment, there is a spectacular birding experience to be had.

I stood watching as the man swung his bucket, scattering silvery fish through the air and an extraordinary balletic display commenced. Tall gangling birds pranced across the grass, jostling in competition. Crests were cocked in excitement. Raucous cries rang out. Vast wings were spread like grey capes, as strong orange beaks grasped their catch. Long, sinuous necks bulged as it was swallowed.

The scene was Barcelona zoo, and the birds putting on the show were Grey herons (Ardea cinerea). Common enough species but rarely seen in such quantities and proximity. The zoo has over 200 of them, nesting high in the tree tops: the largest urban heronry in Europe.

The herons are sometimes mistaken by visitors as another exhibit, a decorative extra thrown in for the price of the ticket, like the peacocks who have the run of the place. But they are wild birds who have chosen to live in close proximity to man. When hunting for food outside the zoo grounds, they revert to extreme wariness, fleeing at the slightest human intrusion. Inside, other rules apply, providing a tremendous opportunity to observe them close up.

Walking through the zoo on a mild April morning, I spotted a heron in a palm tree snaking its neck to pluck some likely nesting material. Another had alighted in a plane tree to present a long twig to its mate. The pair raised their crests in greeting and exchanged raucous ruarks. Over by the penguin pool, herons kept guard, glassy eyes giving nothing away as they waited for feeding time.

Like Barcelona itself, the zoo can be noisy and crowded. A pretend train laden with visitors was winding along the paths, its bell ringing incessantly. The Cuban flamingos were in display mode, trumpeting in formation. Peacocks were screaming. Children on a school trip were shouting “Baloo! Baloo!” at a pair of slumbering Spanish brown bears. Adding to the congestion were lines of wide-eyed tiny-tots hanging onto long ropes. Dodging all these obstacles were the zoo staff, mounted on bikes.

The heronry adds a few more decibels to the general cacophony. As I approached the pelican and gorilla enclosures, a sign instructed me to look up. Overhead, in the towering plane trees, was the hub of the colony, where the large nests are packed close together and the whiff of a barnyard hangs in the air. Also emanating from above was a peculiar racket.

Scanning the boughs to find its source, I saw that several nests were already occupied by goggle-eyed spiky heads. The relentless nattering was the sound of ravenous heron chicks, leaning out precariously, wobbling their throats and demanding food.

Although still weeks away from acquiring the sleek elegance of their parents, some of the chicks were already quite grown, a sign of the colony’s success. Mild Barcelona weather and an ample food supply encourage early breeding. A record was set in 2007, after a particularly balmy winter, when the first chick hatched on January 8th. With such favourable conditions, some herons undertake two broods a year.

For more information I consulted Josep Garcia, an ornithologist who has studied Barcelona’s herons for more than 20 years. Spring is his busiest time as he monitors the entire heron population of Catalonia, wading unsteadily through lagoons, and climbing shaky ladders to peer at nests and ring chicks. In the zoo he has the amenities of a city at hand, and glides smoothly upwards in a tree pruner’s lift.

“You’ve visited the oldest Catalan heronry,” he explained, giving me a quick history lesson. “It was founded over thirty years ago in 1974 by captive birds with clipped wings. Two of their offspring were given their freedom, surprising everyone by returning to the zoo to breed.” Other herons passing on migration were attracted by the nests they spotted below.

“This year we might get as many as 130 nests,” says García, astounded by the prospect himself “Which is probably saturation point. The Barcelona heronry will be playing an important role in reinforcing or establishing new colonies as herons disperse. In the next few years, the Catalan colonies will acquire a great strategic importance as a nexus between heronries of southern France and the Mediterranean basin.” This has always been the role of Catalonia, to act as a bridge between Europe and Spain.

A benign climate is not the only advantage for Barcelona’s herons. In the centre of the city they have few predators to worry about. The principle danger for the chicks is falling from the nest or being pushed by a rival sibling. Conditions are much harsher in the Llobregat Delta by Barcelona airport, where herons nest among reeds. García explains that these “suffer intense predatory pressure from the introduced American mink and disturbance from boars [whose population has exploded in Catalonia in recent years]. Besides having to contend with the more “normal” predators such as the Marsh harrier and other raptors like the Bonelli’s eagle.”

Just as my neck was staring to ache from so much tree-top gazing, a keeper approached the pelican enclosure and the herons began parachuting down. I felt the turbulence generated by a 1.75 metre wingspan as one settled by my elbow. Ignoring me, it only had eyes for the bloke with the bucket.

The heron is an adaptable bird and some have learnt to take advantage of the zoo’s resources. As feeding time is short and competition fierce, their typical hunting techniques, based on patience and stealth, are of little use. Smaller and more nimble rivals, such as Yellow-legged gulls and Little egrets, send tension levels even higher.

A stressed heron is an electrical sight, as its most decorative feathers rise to the occasion. As they gathered nervously in the pelicans’ moat, long black head plumes were springing up like antennae and white neck fringes spiking out. When fish were flung their way, tugs of war erupted. One intrepid individual managed to poach an entire trout, which it slowly engulfed, like a python. The long neck, so useful for harpooning fish in shallow water, also came in handy when accepting an offering directly from the keeper’s hand, keeping him safely “at neck’s length”.

When nerves and feathers had subsided, the herons reverted to more archetypal behaviour, stalking the area with measured calm in search of forgotten morsels. Soon the grassy arena of earlier feeding battles was taken over by picnicking families.

I reflected on how much the flamboyant herons have transformed the zoo, by providing a counterbalance to the captive animals. They are now part of an increasingly valued biodiversity within its grounds. A wintering kingfisher has been known to slip into the aquarium through an open window. Unique in the city, a population of hedgehogs has been discovered, survivors of a pre-urban era. Six species of butterfly have been identified and three amphibians: the Iberian Water Frog, Midwife toad and Stripeless Treefrog. Adjacent to the Parc de la Ciutadella, (Citadel Park ) the zoo has an impressive collection of 96 species of trees. While it is acknowledged that modern zoos work hard at conservation on a global scale, linking up to form a worldwide network, they have another role to play: providing an oasis for local wildlife and encouraging visitors to appreciate it.

Later that week, when walking down Barcelona ‘s expensive central shopping boulevard, Passeig de Gracia, at twilight, I was thrilled to see the instantly recognisable silhouettes of two herons. Curved necks tucked in, broad wings steadily beating, they were heading home.

Facts:

  • The zoo heronry was founded in 1974.
  • Until 1992 it was the only stable heron breeding colony in Catalonia.
  • In 1997 the herons were joined by two other members of the ardeidae family: the Cattle egret and Little egret.
  • Landmark years in the colony’s growth were 1997, when 21 new pairs swelled the number of nests to 62, and 2003, when they reached 106.
  • The breeding period in the zoo can begin from the end of December until the end of July or beginning of August. This year the first egg hatched on February 14th. In 2007 it was as early as January 8th.
  • On average 4 eggs are laid per nest, and only 1 or 2 chicks survive.
  • Between 20 and 30% of the colony is resident. The others begin leaving in August, and return in February