Zino's petrel (''Pterodroma madeira'') or the freira, is a species of small

seabird Seabirds (also known as marine birds) are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same enviro ...

in the

gadfly petrel The gadfly petrels or ''Pterodroma'' are a genus of about 35 species of petrels, part of the seabird order Procellariiformes. The gadfly petrels are named for their speedy weaving flight, as if evading gadflies (horseflies). The flight action is ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to the island of

Madeira ) , anthem = ( en, "Anthem of the Autonomous Region of Madeira") , song_type = Regional anthem , image_map=EU-Portugal_with_Madeira_circled.svg , map_alt=Location of Madeira , map_caption=Location of Madeira , subdivision_type=Sovereign st ...

. This long-winged petrel has a grey back and wings, with a dark "W" marking across the wings, and a grey upper tail. The undersides of the wings are blackish apart from a triangle of white at the front edge near the body, and the belly is white with grey flanks. It is very similar in appearance to the slightly larger

Fea's petrel The Fea's petrel (''Pterodroma feae'') is a small seabird in the gadfly petrel genus, '' Pterodroma''. It was previously considered to be a subspecies of the soft-plumaged petrel (''P. mollis''), but they are actually not closely related at al ...

, and separating these two

Macaronesia Macaronesia (Portuguese: ''Macaronésia,'' Spanish: ''Macaronesia'') is a collection of four volcanic archipelagos in the North Atlantic, off the coasts of Africa and Europe. Each archipelago is made up of a number of List of islands in the At ...

n species at sea is very challenging. It was formerly considered to be a

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

of the

soft-plumaged petrel The soft-plumaged petrel (''Pterodroma mollis'') is a species of seabird in the family Procellariidae. Distribution It breeds on islands in the Southern Hemisphere, nesting on Tristan da Cunha, Gough Island, the Prince Edward Islands, Crozet ...

, ''P. mollis'', but they are not closely related, and Zino's was raised to the status of a species because of differences in

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines * Morphology (archaeology), study of the shapes or forms of artifacts * Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ...

, calls, breeding behaviour and

mitochondrial DNA Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial D ...

. It is Europe's most endangered seabird, with breeding areas restricted to a few ledges high in the central mountains of Madeira. Zino's petrel nests in burrows which are visited only at night, when they give their haunting calls. The single white egg is incubated by both adults, one sitting during the day while the other feeds on fish and squid at sea. Eggs, chicks and adults have been subject to predation by introduced cats and rats, and in the past have been taken for food by local shepherds. Predator control, and other measures such as the removal of grazing animals that trample the burrows, have enabled the population to recover to 65–80 breeding pairs; the species remains listed as

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

. However, conservation efforts had a major setback in August 2010 when fires killed three adults and 65 percent of the chicks. The population eventually recovered and was stable at 160 individuals by 2018.

Taxonomy

The gadfly petrels in the genus '' Pterodroma'' are seabirds of temperate and tropical oceans. Many are little-known, and their often similar appearance have caused the taxonomy of the group to be rather fluid. The forms breeding in Macaronesia on Madeira, Bugio in the

Desertas Islands The Desertas Islands ( pt, Ilhas Desertas, , "Deserted Islands") are a small archipelago in the Atlantic Ocean, part of the larger Portuguese Madeira Archipelago. The archipelago is located off the coast of Morocco. Deserta Grande Island is loca ...

, and in the

Cape Verde , national_anthem = () , official_languages = Portuguese , national_languages = Cape Verdean Creole , capital = Praia , coordinates = , largest_city = capital , demonym ...

archipelago were long considered to be subspecies of the Southern Hemisphere soft-plumaged petrel, ''P. mollis'', but

analysis, and differences in size, vocalisations, breeding behaviour, showed that the northern birds are not closely related to ''P. mollis'', and that the

Bermuda petrel The Bermuda petrel (''Pterodroma cahow'') is a gadfly petrel. Commonly known in Bermuda as the cahow, a name derived from its eerie cries, this nocturnal ground-nesting seabird is the national bird of Bermuda and can be found pictured on Bermudi ...

or Cahow may be the closest relative of the Macaronesian birds. Ornithologist

George Sangster George Sangster is a Dutch ornithologist. He specialises in taxonomy and has written many articles on this subject for the magazines Dutch Birding ''Dutch Birding'', originally subtitled ''Journal of the Dutch Birding Association'', and curren ...

recommended establishing Zino's petrel on Madeira and

on the Desertas and Cape Verde as full species, and the species split was accepted by the Association of European Rarities Committees (AERC) in 2003. Nunn and Zino estimated that the two Macaronesian species diverged at the end of the

Early Pleistocene The Early Pleistocene is an unofficial sub-epoch in the international geologic timescale in chronostratigraphy, being the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently estimated to span the time ...

, 850,000 years ago. An analysis of feather

lice Louse ( : lice) is the common name for any member of the clade Phthiraptera, which contains nearly 5,000 species of wingless parasitic insects. Phthiraptera has variously been recognized as an order, infraorder, or a parvorder, as a result o ...

taken from Fea's petrels, ''Pterodroma feae deserti'', from Bugio Island, and from Zino's petrels from the Madeiran mainland showed that there were marked differences between the two seabirds in terms of the parasites they carried, suggesting that they have long been isolated since

can normally only be transferred through physical contact in the nest. The species on Zino's petrel are most similar to those of the Bermuda petrel, whereas Fea's petrel's lice are like those of Caribbean and Pacific ''Pterodroma'' species. This suggests that despite the close physical proximity of the two species of gadfly petrel found in the Madeiran archipelago, they may have arisen from separate colonisations of mainland Madeira and, later, the

. Although their reproductive isolation has allowed the separate evolutionary development of the two species, genetic evidence shows the three Macaronesian petrels are each other's closest relatives. The petrels breeding in the high central mountains of Madeira were first recorded in 1903 by German naturalist and priest

Ernst Johann Schmitz Ernst Johann Schmitz (18 May 1845 – 3 December 1922) was a German naturalist, ornithologist, entomologist and Roman Catholic priest who settled in Madeira in the late 1870s, serving as vice chancellor of the Funchal Seminary from 1891 to 189 ...

, who failed to realise that they were different from the Fea's petrels he had seen in the Desertas. The species was formally described as a race of soft-plumaged petrel by Australian amateur

ornithologist Ornithology is a branch of zoology that concerns the "methodological study and consequent knowledge of birds with all that relates to them." Several aspects of ornithology differ from related disciplines, due partly to the high visibility and th ...

Gregory Mathews Gregory Macalister Mathews Order of the British Empire, CBE FRSE FZS FLS (10 September 1876 – 27 March 1949) was an Australian-born amateur ornithologist who spent most of his later life in England. Life He was born in Biamble, New South Wal ...

in 1934. Following the recognition of the Madeiran birds as a full species, they were named after the British ornithologist,

Paul Alexander Zino Paul Alexander Zino (9 February 1916 – 3 March 2004) was a British businessman and ornithologist after whom Zino's petrel (''Pterodroma madeira'') is named. Zino was born in Madeira to a British family of land dealers and was educated in ...

, who was instrumental in their conservation during the latter half of the twentieth century. The genus name ''Pterodroma'' is derived from Greek ''πτερον'', ''pteron'', "a wing", and ''δρομος'', ''dromos'', "running", and refers to the bird's swift erratic flight. The specific ''madeira'' refers to the island on which it breeds. The Portuguese name ''Freira'' means "nun"; the inhabitants of

Curral das Freiras Curral das Freiras ("Pen of the Nuns") is a civil parish in the municipality of Câmara de Lobos in the Portuguese archipelago of Madeira. The population in 2011 was 2,001, in an area of 25.03 km².BP were found in two cave sites in Gibraltar. They consist of a more abundant form similar in size to Zino's, and a larger, less common type. It is uncertain whether they represent the site of a former breeding colony, or are the result of a seabird wreck in which storms blow birds inland. They do suggest, however, that members of the genus were formerly more widespread.

Description

This long-winged petrel is long with an , and an average weight of 290 g (10.3 in). It has a grey , grey wings with a dark "W" marking across them, and a grey upper tail. The undersides of the wings are blackish, apart from a triangle of white at the front edge near the body, and the is white with grey . The head has a mottled whitish-brown , a dark cap, and a dark spot below and behind the brown eye. The is black and the legs are flesh pink, the colour continuing onto the first third of the feet, the rest of the toes and webs being black-brown. It gives the general impression of a small Cory's or

great shearwater The great shearwater (''Ardenna gravis'') is a large shearwater in the seabird family Procellariidae. It breeds colonially on rocky islands in the south Atlantic. Outside the breeding season it ranges widely in the Atlantic. Taxonomy The great s ...

, with a fast flight; in strong winds it shears high above the surface with angled wings. Nothing is known of the fresh juvenile or the

moult In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is the manner in which an animal routinely casts off a part of its body (often, but not always, an outer ...

sequence, and age assessment is currently not feasible. This species is very similar in appearance to the

, but is smaller. The size difference and lighter flight may not be apparent at sea, especially with lone birds, but a recent study helped to clarify other useful features. Zino's has a diagnostically small, delicate, often rather long and slender bill, which may be obvious in the most slender-billed examples, which are probably mostly females, but can be difficult to determine in larger-billed, probably adult male, birds. Another useful feature is a large whitish panel on the . The wing panel is exclusive to Zino's but is only shown by 15% of the birds. Zino's has a more rounded wing tip, but ''P. feae deserti'' sometimes shows a rounded wing tip, so this feature is not diagnostic. Previously suggested criteria such as head, upper wing and flank patterns were found to be inconclusive. Off the eastern United States and the Azores, both Macaronesian petrels are easily distinguished from the larger Bermuda petrel by that species' , which are uniformly dark but for a pale grey . This species at its breeding sites gives a long mournful call like the hooting of a

tawny owl The tawny owl (''Strix aluco''), also called the brown owl, is commonly found in woodlands across Europe to western Siberia, and has seven recognized subspecies. It is a stocky, medium-sized owl, whose underparts are pale with dark streaks, an ...

, and a much less frequent sound like the whimpering of a pup. It is silent at sea. The breeding calls are very similar to those of Fea's petrel, and Bretagnolle's analysis of the calls of the soft-plumaged petrel complex led him to suggest in 1995 only a two-way species split, with the northern forms ''madeira'', ''feae'' and ''deserti'' all as subspecies of Fea's petrel.

"Snowy-winged petrel"

The

Hadoram Shirihai Hadoram Shirihai (born in Israel 1962) is an Israeli ornithologist and writer. Biography Shirihai is the son of Batia and Eli Shirihai. His mother was a schoolteacher, his father was a zoologist in Israel. He grew up in Jerusalem where he becam ...

expeditions to the Madeira archipelago in 2008, 2009, and 2010 each had sightings of a ''Pterodroma'' petrel (possibly the same bird) with largely white underwings, but upper wings like Zino's or Fea's. This plumage does not correspond to any known ''Pterodroma'' species. It may have been an unusual variant of Zino's but this is unlikely since no similar bird has been seen amongst the more than 100 caught at the nest. It may alternatively be a single aberrant individual, a hybrid or an unknown taxon from Madeira or elsewhere. No conclusion is possible on current knowledge.

Distribution and habitat

Zino's petrel is endemic to the main island of Madeira, where it breeds on inaccessible and well-vegetated ledges in the central mountains between Pico do Arieiro and

Pico Ruivo Pico Ruivo is the highest peak on Madeira Island. It can be reached only by foot, usually either from Pico do Arieiro (3rd highest) after a strenuous hike, or from Achada do Teixeira via a shorter, easier trail. There is an additional trail leadin ...

. The typical ledge plants are endemic hemicryptophytes and chamaephytes, but grasses may also be present. It nests at heights above . It was formerly more widespread, since

subfossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...

remains have been found in a cave in eastern Madeira, and on nearby

Porto Santo Island Porto Santo Island () is a Portuguese island northeast of Madeira Island in the North Atlantic Ocean; it is the northernmost and easternmost island of the archipelago of Madeira, located in the Atlantic Ocean west of Europe and Africa. The muni ...

. The breeding ledges have to be inaccessible to introduced goats so that they remain rich in endemic flora. The vegetation ensures that there is sufficient earth on the ledges to allow the birds to burrow and make their nests, and trampling by grazing animals reduces the soil cover. This petrel is only present in Madeiran waters during the breeding season. Its distribution at sea during the rest of the year is poorly known due to the rarity of the species and the difficulty of separating it from other ''Pterodroma'' petrels at sea. Birds identified as either Zino's or Fea's have been recorded from both sides of the North Atlantic, and in Ireland and Britain there has been a large increase in the number of reports, perhaps because

global warming In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...

brings increasing numbers of tropical species into temperate waters. The timing of the reports, mainly in late spring and summer in the western North Atlantic, and in late summer and early autumn in the east, has suggested that birds follow a clockwise route around the North Atlantic after leaving their breeding sites. However, the few birds that have been identified with certainty have all been Fea's. Zino's petrel may have a similar strategy since preliminary results from geolocation studies indicate widespread dispersal over the North Atlantic central ridge during the breeding season and migration towards the Brazilian coast in the non-breeding period. ''Pterodroma'' petrels have been recorded in the

Canary Islands The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocc ...

and the

Azores ) , motto =( en, "Rather die free than subjected in peace") , anthem= ( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...

on surprisingly few occasions; a claim of possible Zino's from South Africa is now thought to be erroneous.

Behaviour

Breeding

Zino's petrel breed two months earlier than the Fea's petrel on Bugio, only away. The birds return from sea to their breeding grounds in late March or early April and courting occurs over the main breeding area during the late evening and early morning hours. The nest is a shallow burrow or old rabbit tunnel up to long in thick soil on vegetated ledges. The length of the burrow is related to the age of the pair that uses it, young birds making shorter tunnels, which are extended in subsequent years. The oval white egg is laid from mid-May to mid-June in a chamber at the end of the burrow and for 51–54 days, each parent alternating between sitting on the nest and feeding at sea. The young

fledge Fledging is the stage in a flying animal's life between hatching or birth and becoming capable of flight. This term is most frequently applied to birds, but is also used for bats. For altricial birds, those that spend more time in vulnerable c ...

about 85 days later in late September and October. This petrel is strictly nocturnal at the breeding sites to avoid predation by

gull Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. They are most closely related to the terns and skimmers and only distantly related to auks, and even more distantly to waders. Until the 21st century, m ...

s. It stays offshore during the day, coming to land in darkness. It calls from about 30 minutes after nightfall until dawn, including on moonlit nights. This species mates for life and pairs return to the same burrow year after year. The single egg is not replaced if lost. This is a long-lived species: one individual was observed to return to its burrow for ten consecutive years, and the lifespan is estimated to be about 16 years. The age of first breeding is unknown but assumed to be four or more years. Despite the proximity of their breeding sites, Zino's and Fea's petrels have never been found at each other's nesting areas, and Zino's is not known to hybridise with any other species.

Feeding

Zino's petrel, like its relatives, feed on small squid and fish. The vomited stomach contents of one bird contained

cephalopod A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head ...

s, the bioluminiscent fish ''

Electrona risso ''Electrona risso'' is a species of myctophiform ray-finned fish in the family Myctophidae, the lanternfishes. It is known commonly as the electric lantern fish, chubby flashlight fish,Hulley, P. 2015''Electrona risso''.The IUCN Red List of Threa ...

'' and small

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...

s. Like other small petrels, Zino's does not normally follow ships.

Predators and parasites

Their nocturnal approach to the breeding sites means that Zino's petrels avoid the attentions of gulls or diurnal raptors, and the only owl on the island, the

barn owl The barn owl (''Tyto alba'') is the most widely distributed species of owl in the world and one of the most widespread of all species of birds, being found almost everywhere except for the polar and desert regions, Asia north of the Himalaya ...

, is a rodent hunter. Other than bats, there are no native land mammals on Madeira, although there are a number of introduced species, two of which will take birds or chicks. These are

brown rat The brown rat (''Rattus norvegicus''), also known as the common rat, street rat, sewer rat, wharf rat, Hanover rat, Norway rat, Norwegian rat and Parisian rat, is a widespread species of common rat. One of the largest muroids, it is a brown o ...

s and feral domestic

cat The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...

s. Even the high mountain nest sites of the Zino's petrel are not safe from these adaptable predators, ten adults being killed by cats in 1990. Feather

found on Zino's petrels include '' Trabeculus schillingi'', ''

Saemundssonia ''Saemundssonia'' is a genus of chewing lice belonging to the family Philopteridae. These lice are parasitic on aquatic birds, especially on members of the order Charadriiformes, but also on Anseriformes, Gruiformes, Pelecaniformes and Procell ...

'' species and an unnamed species of '' Halipeurus''.

Conservation status

Zino's petrel has a very restricted range on the mountaintops of a single island and is the most endangered European seabird. The birds, already confined to a limited area when discovered, were thought to be extinct by the mid-twentieth century. Two freshly fledged juveniles were found within the walls of the governor's palace in

Funchal Funchal () is the largest city, the municipal seat and the capital of Portugal's Madeira, Autonomous Region of Madeira, bordered by the Atlantic Ocean. The city has a population of 105,795, making it the sixth largest city in Portugal. Because of ...

in the early 1940s, presumably attracted there by lights, but the species was not seen again until 1969. In 1969, Paul Zino played a tape of Fea's petrel from Bugio to a shepherd from Curral das Freiras; he immediately recognised the call and led the researchers to the remaining nesting area. Predation by introduced rats meant that breeding success in the small population was low, and no young at all fledged in 1985. The Freira Conservation Project was founded in 1986 with the aim of increasing the population of Zino's petrel by controlling rats and human interference; the control was extended to cats after the mass predation of 1990. There are now 130–160 known individuals (65–80 breeding pairs) confirmed to breed on just six ledges. There may be some disturbance from visitors at night and from the construction of a NATO radar station on the summit of Mount Arieiro, and in the longer term climate change may have an adverse effect, since all nests are within of the top of the highest mountain in the breeding area. Formerly, shepherds collected nestlings for food, and egg collectors have raided burrows. Currently, the main threats continue to be predation of eggs and chicks by

rats Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, but stereotypical rats are found in the genus ''Rattus''. Other rat genera include ''Neotoma'' (pack rats), ''Bandicota'' (bandicoot ...

, and of nesting adults by

feral cat A feral cat or a stray cat is an unowned domestic cat (''Felis catus'') that lives outdoors and avoids human contact: it does not allow itself to be handled or touched, and usually remains hidden from humans. Feral cats may breed over dozens ...

s, although at much reduced levels due to trapping. Zino's petrel is protected under the EU's Wild Birds Directive, and its breeding sites lie within the Parque Natural da Madeira

national park A national park is a nature park, natural park in use for conservation (ethic), conservation purposes, created and protected by national governments. Often it is a reserve of natural, semi-natural, or developed land that a sovereign state dec ...

. Following the purchase of about of land around the main breeding site, all livestock has been removed from the breeding areas, allowing the vegetation to recover, although breeding still only occurs on ledges that were never accessible to grazing animals. The research and predator control by the Freira Conservation Project and the national park which started in 1986 was expanded in 2001 with additional EU funding. The increase in productivity (29 chicks fledged in 2004) meant that this species was downgraded from critically endangered to endangered on the IUCN Red List in 2004. Its population appeared to be stable or increasing slightly up to the summer of 2010. A disaster struck the colony on 13 August 2010, when a forest fire swept through the breeding site killing three adults and 25 of the 38 chicks. The fire destroyed the vegetation and several nesting burrows. Conservation action to protect the 13 remaining chicks included removing dead birds and burnt vegetation, reinforcing the surviving nests, and setting poison bait for rats around the now exposed nest sites. The action plan also included the provision of artificial burrows, seed dispersal to help the vegetation recover, and the use of anti-erosion materials. By 2018, the colony had recovered and was stable at 160 adults.

References

External links

* Madeira Birds
Zino's petrel
{{Taxonbar, from=Q1272830

Zino's petrel Zino's petrel (''Pterodroma madeira'') or the freira, is a species of small seabird in the gadfly petrel genus, endemic to the island of Madeira. This long-winged petrel has a grey back and wings, with a dark "W" marking across the wings, and a ...

Birds of Madeira Endemic fauna of Madeira Endangered biota of Africa