Seabirds of the Mountain, Pico do Arieiro, Madeira

Madeira is the top of a massive shield volcano that rises 6km from the sea floor in the northern Atlantic Ocean forming an archipelago of four islands. It is roughly 520km away from north western coast of Africa. Madeira is well known for its unusual plants and endemic species although throughout its history it has been changed by man. Due to the climate the island was once covered by subtropical rainforest known as laurisilva (laural forest) which has existed for 1.8 million years. Sadly it is now only common in a few areas of the island but is home to few species of endemic birds and plenty of plants which will be detailed in another post.

Pico do Arieiro at sunset

I'd been lucky enough to be invited by Mark Cutts with the Royal Naval Birdwatching Society (RNBWS) for a week of birding (and botany for me),and with luck and the help of Frank Zino to hopefully see one of the island rarest inhabitants.

A sea of cloud below the peaks

Running through the spine of the island is an area of jagged peaks, one of these is particularly special due to an unusual breeding species. At 1,818 m (5,965 ft) Pico do Arieiro is Madeiras third highest peak, high above the clouds its the last place you'd expect to find one of the rarest bird species in Europe . Its also a treasure trove of endemic plant species which either cling to the rocky cliffs or survive on the narrow shallow ledges.

Pride of Madeira, Echium candicans

One strange thing about travelling up towards Pico do Arieiro is the layer of cloud which you have to travel through to get to the top, the mountain sitting within a sea of cloud making it seem you were at a much lower elevation. Although barren looking, any crevice or ledge was covered in plants. Of these by far the most spectacular in flower was the Pride of Madeira Echium candicans, a large sub-shrub member of the family Boraginaceae.

Everywhere I looked it seemed another stunning endemic plant which had managed to get a foothold in the crumbling rock making it seem like a botanist paradise, which of course it was. Many of the plants had adapted to the extremes of temperature which can occur daily at Pico do Arieiro. Succulents were common and well adapted with fleshy leaves, although not easy to identify. The Disk Houseleek Aeonium glandulosum was one such plant, endemic to the islands which make up the Madeira archipelago where it is limited to these high barren rock faces. Many species look similar to plant species found withing Europe and North Africa but have eventually evolved due to their thousands of years of isolation, one such species was Madeiran Thrift Armeria Maderensis which looks superficially similar to the species I regularly see on the sea cliffs of Mid-Wales.

Although I was distracted by all the flora, it was really the fauna I had come to see but for that we'd have to wait until it got dark. Whilst waiting we had plenty of time to watch the endemic Plain Swifts Apus unicolor screaming over the ridges and into the valleys below. A male Spectacled Warbler Sylvia conspicillata was announcing his territory from a dense bit of scrub, while his partner was busy collecting caterpillars to feed their brood in a low gorse bush. A few tattered Macaronesian Red Admiral Vanessa vulcania bathed on the eroded summit, gathering the last warmth from the sinking sun.

Spectacled Warbler Sylvia conspicillata

After setting the nets along a narrow ridge, all we had to do was wait. Just like clockwork, at 10.45 each evening we heard some strange sounds calling from the inky blackness. For many years the shepherds of Curral das Freiras mistakenly thought this to be the sounds of suffering souls of the shepherds or nuns who lost their lives in the mountains. The source of the noise probably never went silent but was forgotten about, believed extinct until in 1969 Alec Zino played a call of Fea's Peterel to a local Shepard who recognised the eerie walling and took them to the area now regarded as the breeding ledges. For us the journey was easy, well maintained paths allow us to view the area in relative safety, for Frank and his father back in 1969, a narrow shepherds track was all that separated them from a drop into the deep valleys on either side, a treacherous place for a nocturnal walk. I don't think i'll ever forget the first time I heard that strange wailing in the distant inky blackness or the occasional shadow pass over the starlit sky. To me the calls didn't sounds eerie, they sounded almost friendly. Frank noted the number of calls each 15 minutes, keeping count with a clicker. Although the calls were regular for a couple of days all I managed to see was a few glimpses of these mysterious birds.

Then at 11pm on our third night as I was walking to the far end of the net something hit the net in front of me, a pale bellied shape hanging in the gloom. A Freira Pterodroma madeira, more commonly known as Zino's Petrel, named after the family which have done so much for the identification and conservation of this species. Originally the birds found breeding within macaronesia were thought be part of the Soft-plumaged Petrel Pterodroma mollis complex but but mitochondrial DNA analysis and further differences in size, vocalisations, breeding behaviour have shown that the macronesian birds are not closely related to Pterdroma mollis. Sangster further recommended splitting between the macronesian birds, which was further supported by Nunn & Zino based on analysis of feather lice on birds from Madeira and Bugio Island which have been estimated to have split 850,000 years ago. More recent work has splitting the birds found on the Desertas islands from the birds found on Cape Verde Island creating the Desertas Petrel Pterodroma deserta and the Fea's Petrel Pterodroma feae although the identification of this complex of species is still confusing, especially in the field.

The Freira, Pterodroma madeira. Europes rarest seabird.

The Freira is the most endangered species of sea bird in Europe with an estimated population of 80 known pairs. Due to this it was a little surprising then that the bird we caught was a new un-ringed bird allowing Mark to ring it. The population is well monitored with majority of chicks ringed in the nest and many of the adult bird caught during the previous years, even more surprising was the second bird caught a couple of nights, during quite a blow, I watched nervously as it bounced out  of the net, only to go in again seconds later by which time I was already upon  it. Being a new bird gave me the opportunity to ring a bird, under the supervision of Frank. They really are a very pretty bird with an amazing wingspan, their webbed feet and sharp claws, their delicate soft plumage which gives the name to their relatives is evident in the hand.

Madeiran rings, you know its special if you find one of these

Freira's are one of two species to be ringed using Madeira rings (the other being the Deserta/feae Petrel complex). Although the moult sequence, and ageing birds is currently not feasible, if anyone would know it would be Frank who seemed to think both of these birds were likely to be third year birds checking out the breeding colony before breeding themselves. Blood samples and bio-metrics were taken for each of the birds before they were released back in the night, hopefully to be re-caught in a subsequent years. As each individual is an important breeding bird, which will help to increase this fragile population.

Although the birds breeding ledges are protected within the Parque Natural da Madeira national park and they have shown an increase in productivity over the last 20 years they are still at risk. The fact that only six ledges are used for burrowing and nesting means that degradation to the vegetation from grazing goats, wildfires and predators could still spell disaster for this species. A fire in August 2010 swept through the breeding site killing three adults and 25 of the 38 chicks. Vegetation around the nest sites were destroyed, leaving them open to predators and at risk of erosion. For an island which evolved without ground dwelling mammals, its no surprise that they can cause huge problems. Rats played a significant role in decimating the petrels numbers early on but active trapping has helped eliminate them as such a risk. Feral Cats are now the main cause for concern, previously these were trapped after 10 adults were killed by a single cat in 1990. The government of Portugal have since made trapping cats illegal leaving this delicate population once again at risk from these troublesome tabbies. While up at the breeding ledges we saw several cats but little can be done about it until permission from the government is granted, sadly it may be a long time coming.

This really was one of the most special experiences I've had and will always be one of my birding highlights and it was an honour to be allowed to ring one of these special birds. Frank Zino is tireless in his effort of furthering the protection of these and several other seabirds species in Macronesia, its not often you get to see a species named after the family of the person who shows you but now I needed to see a Pterdroma at sea.