Canarian Black Oystercatcher
Encyclopedia
The Canarian Oystercatcher or Canary Islands Oystercatcher, Haematopus meadewaldoi,
was a shorebird endemic to Fuerteventura
Fuerteventura
Fuerteventura , a Spanish island, is one of the Canary Islands, in the Atlantic Ocean off the coast of Africa. It is situated at 28°20' north, 14°00' west. At 1,660 km² it is the second largest of the Canary Islands, after Tenerife...

, Lanzarote
Lanzarote
Lanzarote , a Spanish island, is the easternmost of the autonomous Canary Islands, in the Atlantic Ocean, approximately 125 km off the coast of Africa and 1,000 km from the Iberian Peninsula. Covering 845.9 km2, it stands as the fourth largest of the islands...

, and their offshore islets (Islote de Lobos and the Chinijo Archipelago
Chinijo Archipelago
The Chinijo archipelago is an archipelago located in the northeastern part of the Canary Islands. The archipelago includes the islands of Montaña Clara, Alegranza, Graciosa, Roque del Este, Roque del Oeste and various islands of volcanic origin....

) in the Canary Islands
Canary Islands
The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...

, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

.

Hockey (1982) showed that the Canarian Oystercatcher was a full species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 distinct from the African Oystercatcher Haematopus moquini, of which it was formerly considered a subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

; these two were occasionally lumped as subspecies of the Eurasian Oystercatcher
Eurasian Oystercatcher
The Eurasian Oystercatcher Haematopus ostralegus, also known as the Common Pied Oystercatcher, or just Oystercatcher, is a wader in the oystercatcher bird family Haematopodidae. It is the most widespread of the oystercatchers, with three races breeding in western Europe, central Eurasia,...

. Though this bird was known to naturalists since long, it was considered a mere local population of the African Black Oystercatcher until 1913 (Bannerman 1913).

Description

The Canarian Oystercatcher was of similar size as its relatives, the African and Eurasian Oystercatchers, or about 40-45 cm (around 16.5 in); comparing with the non-migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...

 African species, it probably weighed between 600-800 gram
Gram
The gram is a metric system unit of mass....

s in life, with females being slightly heavier. Its bill was some 70-80mm long in males and markedly longer (around 80mm) in females; the tarsus
Tarsus (skeleton)
In tetrapods, the tarsus is a cluster of articulating bones in each foot situated between the lower end of tibia and fibula of the lower leg and the metatarsus. In the foot the tarsus articulates with the bones of the metatarsus, which in turn articulate with the bones of the individual toes...

 measured around 50 mm, and the wings were around 250-265mm long, with males possibly at the upper range of that size (Bannerman 1963).

Its appearance was extremely similar to the African species, to the extent that even hand-held specimens can hardly be told apart except by direct comparison or measurements. Its bill was longer and its wings were shorter than in the African species, which is not known to occur north of Lobito
Lobito
Lobito is a town and municipality in Benguela Province in Angola.It dates from 1905 and owes its existence to the bay of the same name having been chosen as the sea terminus of the Benguela railway to the far interior, passing through Luau to Katanga in the Democratic Republic of the Congo. The...

, Angola
Angola
Angola, officially the Republic of Angola , is a country in south-central Africa bordered by Namibia on the south, the Democratic Republic of the Congo on the north, and Zambia on the east; its west coast is on the Atlantic Ocean with Luanda as its capital city...

 however, at least in modern times.
H. meadewaldoi had a glossy black coloration overall save for the whitish underwing bases of the primary remiges' inner webs, but this may have not been present in worn plumage which also was duller (Bannerman 1963). Its bill, lateral
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...

ly compressed and with a blunt, lighter tip, and a narrow naked ring around the red eye were reddish orange, and the legs and feet were dark pink with ivory-colored nails. As usual in oystercatchers, it had no hallux
Hallux
In tetrapods, the hallux is the innermost toe of the foot. Despite its name it may not be the longest toe on the foot of some individuals...

 and the second and third toes were connected by a small web (Álamo Tavío 1975).

The sexes did not differ in color; juvenile birds are unknown but probably had duller bare parts and some greyish-buff fringes to the feathers. The coloration of down
Down
Down may refer to:* Relative direction, where down is the direction towards the centre of gravity of a celestial object.* Railroad directions, where down and up have locally significant meanings...

y young is likewise unknown; these are generally brownish-grey above with dark striping to provide camouflage
Camouflage
Camouflage is a method of concealment that allows an otherwise visible animal, military vehicle, or other object to remain unnoticed, by blending with its environment. Examples include a leopard's spotted coat, the battledress of a modern soldier and a leaf-mimic butterfly...

 against predators such as gull
Gull
Gulls are birds in the family Laridae. They are most closely related to the terns and only distantly related to auks, skimmers, and more distantly to the waders...

s (Hockey 1996); considering the dark lava
Lava
Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...

 rock habitat of this species, they were probably fairly dark overall and had a dusky belly.

Habits

This was apparently an all-year resident, and seems to have never bred or even strayed outside the eastern Canaries at least in historic times. Information about its ecology
Ecology
Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...

 are scant and usually second-hand or inferred
Inference
Inference is the act or process of deriving logical conclusions from premises known or assumed to be true. The conclusion drawn is also called an idiomatic. The laws of valid inference are studied in the field of logic.Human inference Inference is the act or process of deriving logical conclusions...

 from circumstantial information. However, even though conjectural, these informations are consistent as the biology of oystercatchers is not very variable and the present species was a conspicuous bird well-known to locals. It was called cuervo marino ("sea raven") on Fuerteventura, grajo de mar ("sea chough
Chough
The Red-billed Chough or Chough , Pyrrhocorax pyrrhocorax, is a bird in the crow family; it is one of only two species in the genus Pyrrhocorax...

")
on Lanzarote, and corvino ("little raven") on Graciosa
Graciosa, Canary Islands
There is also a Graciosa in the Azores, see GraciosaGraciosa Island or commonly La Graciosa is a volcanic island in the Canary Islands of Spain, located 2 km north of the island of Lanzarote with the strait named Río. It was formed by the Canary hotspot...

. In addition, the local name lapero ("limpet-eater") was also used, possibly on Alegranza
Alegranza
Alegranza is an island in the Atlantic Ocean, located off the coast of Africa and is in the province of Las Palmas in the Canary Islands, Spain. It is the northernmost point in the Canary Islands .- Geographical overview :...

.(Bannerman 1963)

The Canarian Oystercatcher was in all likelihood a bird of the rocky shore rather than sandy beaches; although it might have been driven from the latter as they were much more utilized by humans - which it tended to avoid (Bannerman 1963) -, what is known about its feeding habits indicates that had always been less commonly found in beach habitat. As with all oystercatchers, its diet consisted of small molluscs and crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...

s rather than oyster
Oyster
The word oyster is used as a common name for a number of distinct groups of bivalve molluscs which live in marine or brackish habitats. The valves are highly calcified....

s. Especially the limpet
Limpet
Limpet is a common name for a number of different kinds of saltwater and freshwater snails ; it is applied to those snails that have a simple shell which is more or less conical in shape, and either is not spirally coiled, or appears not to be coiled in the adult snails.The name limpet is most...

s Patella candei
Patella candei
Patella candei is a species of sea snail, a true limpet, a marine gastropod mollusk in the family Patellidae, one of the families of true limpets....

, Patella piperata
Patella piperata
Patella piperata is a species of sea snail, a true limpet, a marine gastropod mollusk in the family Patellidae, one of the families of true limpets.-Description:...

, and Patella cf. ulyssiponensis
Patella ulyssiponensis
Patella ulyssiponensis, common name the rough limpet, or China Limpet is a species of sea snail, a true limpet, a marine gastropod mollusk in the family Patellidae, one of the families of true limpets.- Uses :...

, as well as the African mussel Perna (perna) picta were favorite prey items (Hockey 1996).

Its vocalizations were given as repeated kvirr or kvik-kvikkvik (Álamo Tavío 1975), and the alarm call
Alarm call
In the field of animal communication, an alarm signal is an antipredator adaptation referring to various signals emitted by social animals in response to danger. Many primates and birds have elaborate alarm calls for warning conspecifics of approaching predators. For example, the characteristic...

 peepe-peepe peepe-peepe (Bannerman 1963). The birds appear to have been territorial in the breeding season and vagrant, but not occurring in large groups, at other times (Hockey 1987).

Reproduction

Like other oystercatchers, this species did not build a nest but laid its eggs in a scrape on the seaside; apparently it chose the most deserted locations such as the mouths of barrancos (erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

 gullies); eggs or nests were never recorded by researchers (Hockey 1987). Its courtship was reported to be peculiar, with two or three males joining in a "dancing" display, presenting themselves to best effect (Álamo Tavío 1975). Once the females had chosen a partner, they remained monogamous, probably for life if the pairing proved successful as in most other species of the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

. The clutch size was undocumented but possibly there was only one egg; groups of three, but not four birds were commonly seen (Bannerman 1963). The eggs can be assumed to have been camouflaged as in its relatives (Hockey 1996); in the case of this species, they thus were probably rather dark overall, dull brownish grey with plenty of black, dark brown, and dark purplish splotches and scribbles. Egg size was probably about 60 x 40 mm on average (Bannerman 1963).

The breeding season is also unknown, but from observations of courtship and birds in laying condition, it started around April. Comparison with its relatives suggests that incubation
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...

 lasted for around 30 days, maybe less (23 days: Álamo Tavío 1975), with the chicks taking around 35 days again to fledge
Fledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...

. The three-bird groups started to occur on more populated regions in June (Bannerman 1963). Females took probably 3 years to reach sexual maturity and males 4; this species can be assumed to have been long-lived like other oystercatchers, which not infrequently live for 20 or even more than 30 years (Hockey 1996). Unusually, the birds seem to have molted after breeding season; 2 females shot in Aprim had worn plumage (Bannerman 1963).

Extinction

This bird was last collected in 1913, and local fishermen and lighthouse
Lighthouse
A lighthouse is a tower, building, or other type of structure designed to emit light from a system of lamps and lenses or, in older times, from a fire, and used as an aid to navigation for maritime pilots at sea or on inland waterways....

 keepers reported it had disappeared around 1940 (Hockey 1996), after a prolonged decline starting probably in the 19th century (Hockey 1987). It first - until the early 20th century - seems to have disappeared from Lanzarote, in accord with the general pattern of Canarian extinctions. By 1913, it was not reported to have been found outside the Chinijo Archipelago and Islote de Lobos in recent times (Bannerman 1963).

It is now considered extinct, because extensive surveys between 1956/57 and the late 1980s failed to find any evidence of the Canarian Black Oystercatcher's survival. It was officially declared extinct with publication of the 1994 IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...

.

There have been sight records of altogether 3 black oystercatchers from the coast of Senegal
Senegal
Senegal , officially the Republic of Senegal , is a country in western Africa. It owes its name to the Sénégal River that borders it to the east and north...

, in 1970 (Jarry in Hockey 1987) and 1975 (Ziguinchor Region
Ziguinchor Region
Ziguinchor is a region of Senegal . The region is also referred to historically and popularly as Basse Casamance.-Departments:Ziguinchor region is divided into 3 departments:*Bignona...

: de Ridder 1997), but these are very unlikely to refer to this species which was by all accounts a resident bird never recorded outside the Canaries archipelago on other occasions. Two fairly convincing records from Tenerife
Tenerife
Tenerife is the largest and most populous island of the seven Canary Islands, it is also the most populated island of Spain, with a land area of 2,034.38 km² and 906,854 inhabitants, 43% of the total population of the Canary Islands. About five million tourists visit Tenerife each year, the...

 - apparently in July 1965 or 1968 at Puerto de la Cruz
Puerto de la Cruz
Puerto de la Cruz is a city and municipality located in Spain, on the north coast of Tenerife island, in the Orotava Valley...

 (Bannerman 1969), and in 1981 at El Médano
El Médano
El Médano is a town in the municipality of Granadilla de Abona, on the island of Tenerife, one of the Canary Islands....

 (Kraft in Hockey 1987) -, on the other hand, could indicate that a small population managed to persist on uninhabited islets until the early 1980s, it is interesting to note that second-hand records from Tenerife also exists for the mid-19th century (Bannerman 1963). The Senegal records are nonetheless puzzling, as none of the black species of oystercatcher are known to occur even in the general area; melanism
Melanism
Melanism is an undue development of dark-colored pigment in the skin or its appendages, and the opposite of albinism. It is also the medical term for black jaundice.The word is deduced from the , meaning black pigment....

 is known to occur occasionally in the Eurasian Oystercatcher
Eurasian Oystercatcher
The Eurasian Oystercatcher Haematopus ostralegus, also known as the Common Pied Oystercatcher, or just Oystercatcher, is a wader in the oystercatcher bird family Haematopodidae. It is the most widespread of the oystercatchers, with three races breeding in western Europe, central Eurasia,...

 (Stresemann 1927) which winters in the region; possibly the Senegal birds were such specimens.

Over-harvesting of intertidal invertebrates and disturbance by people was probably the main underlying cause of its decline (Hockey 1987), although predation by rats
RATS
RATS may refer to:* RATS , Regression Analysis of Time Series, a statistical package* Rough Auditing Tool for Security, a computer program...

 and cats has also been implicated. In addition, its eggs were said to be of exquisite taste and consequently much collected (Álamo Tavío 1975). Although oystercatchers generally have adapted
Adaptation
An adaptation in biology is a trait with a current functional role in the life history of an organism that is maintained and evolved by means of natural selection. An adaptation refers to both the current state of being adapted and to the dynamic evolutionary process that leads to the adaptation....

 to the commonplace loss of the first egg in their clutch to predators and readily re-lay lost eggs, if the present species' clutch was indeed only one, egg collecting would have had a major impact: collectors would have to disturb more breeding pairs per number of eggs gathered. Also, adult birds were apparently opportunistically shot together with more plentiful migrant waders in the winter months and sold as salmuera (preserved in brine
Brine
Brine is water, saturated or nearly saturated with salt .Brine is used to preserve vegetables, fruit, fish, and meat, in a process known as brining . Brine is also commonly used to age Halloumi and Feta cheeses, or for pickling foodstuffs, as a means of preserving them...

) (Álamo Tavío 1975). It is unknown how far-reaching the direct impact of unsustainable agriculture practices, which led to widespread desertification
Desertification
Desertification is the degradation of land in drylands. Caused by a variety of factors, such as climate change and human activities, desertification is one of the most significant global environmental problems.-Definitions:...

 especially of Lanzarote by the end of the 19th century (Hockey 1987), was. It might have altered local climate regimes, leading to increased pressure on intertidal habitat e.g. by increased flash floods causing silting of barranco mouths and delines in invertebrate populations there.

There exist apparently only 4 specimens (Bannerman 1963), three collected by Meade-Waldo in the BMNH
BMNH
BMNH may refer to:*British Museum of Natural History, commonly known as Natural History Museum, in London, the United Kingdom*Beijing Museum of Natural History, in Beijing, China...

 and one collected by Bannerman
David Armitage Bannerman
David Armitage Bannerman OBE, MA, SD , Hon. LL.D. , FRSE, FZS was a British ornithologist.-Biography:After graduating from Pembroke College, Cambridge in 1909, Bannerman travelled extensively in Africa, the West Indies, South America and the Atlantic Islands.Rejected on health grounds by the...

 in the World Museum Liverpool
World Museum Liverpool
World Museum is a large museum in Liverpool, England which has extensive collections covering archaeology, ethnology and the natural and physical sciences. Special attractions include the Natural History Centre and a free Planetarium. Entry to the museum itself is also free...

. The type specimen BMNH 1905.12.22.323 is a female shot at Jandía
Jandía
Jandía is an area and a peninsula covering the whole southwestern part of the island of Fuerteventura in the Canary Islands forming the westernmost and the southernmost points on the island. It is mainly mountainous and rocky and has less vegetation than some areas of the island, including palm...

, Fuerteventura, on April 7, 1888 http://internt.nhm.ac.uk/jdsml/research-curation/projects/birdtype/detail.dsml?authorqtype=starts+with&Typeqtype=contains&vol=1&collectorqtype=starts+with&sort=Genus%2cSpecies%2csubspecies&typedescqtype=starts+with&searchPageURL=search%2edsml&subspeciesqtype=starts+with&yearqtype=starts+with&Speciesqtype=starts+with&Genusqtype=starts+with&Genus=haematop&locqtype=starts+with&refer=list&sort=Genus,Species,subspecies&beginIndex=1&listPageURL=list%2edsml%3fauthorqtype%3dstarts%2bwith%26Typeqtype%3dcontains%26vol%3d1%26collectorqtype%3dstarts%2bwith%26sort%3dGenus%252cSpecies%252csubspecies%26typedescqtype%3dstarts%2bwith%26subspeciesqtype%3dstarts%2bwith%26yearqtype%3dstarts%2bwith%26Speciesqtype%3dstarts%2bwith%26Genusqtype%3dstarts%2bwith%26Genus%3dhaematop%26locqtype%3dstarts%2bwith]or 1889 (Bannerman 1963). About the same time in the next year, a couple was taken on Graciosa. From there is also the last known specimen - the male now in Liverpool -, shot on June 3, 1913. It is not known what became of the specimen shot in April 1852, apparently also near Jandía, by Carl Bolle
Carl Bolle
Carl August Bolle was a German naturalist and collector.Bolle was born at Berlin into a wealthy brewing family. He studied medicine and natural science at Berlin and Bonn...

 (Bolle 1855).

See also

  • Extinct birds
    Extinct birds
    Since 1500, over 190 species of birds have become extinct, and this rate of extinction seems to be increasing. The situation is exemplified by Hawaii, where 30% of all known recently extinct bird taxa originally lived...

  • Graja, the endemic La Palma chough
    Chough
    The Red-billed Chough or Chough , Pyrrhocorax pyrrhocorax, is a bird in the crow family; it is one of only two species in the genus Pyrrhocorax...

     subspecies
    Subspecies
    Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

  • List of extinct animals of Europe
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