The archipelago of Fernando de Noronha (c.03°52′S, 32°25′W) comprises 21 islands and islets of volcanic origin, and are the still-visible peaks of a range of submerged mountains that form part of the Mid-Atlantic Ridge. The archipelago lies in the equatorial Atlantic Ocean c.350 km off the coast of north-east Brazil, the nearest mainland being the state of Rio Grande do Norte (for a general description see Teixeira et al. 2003, MMA / IBAMA 2005, Silva e Silva 2008). The islands′ total area is 26 km². The largest and only inhabited island (Fernando de Noronha) has fewer than 3,000 residents.

The resident avifauna, especially breeding seabirds, is well known (Silva e Silva 2008, Mancini et al. 2016), but the archipelago is best known ornithologically for its two endemic passerines, Noronha Vireo Vireo gracilirostris and Noronha Elaenia Elaenia ridleyana.

The islands' remoteness between the African and South American continents make the archipelago also an ideal vagrant trap. The vast majority of vagrants recorded have been European–African migrants such as Purple Heron Ardea purpurea, Grey Heron A. cinerea, Western Reef Heron Egretta gularis, Squacco Heron Ardeola ralloides, Eurasian Spoonbill Platalea leucorodia, Corncrake Crex crex, Eurasian Whimbrel Numenius p. phaeopus and Bar-tailed Godwit Limosa lapponica (Olson 1982, Ebels 2002, Schulz-Neto 2004, Silva e Silva & Olmos 2006, Davis 2010, Burgos & Olmos 2013, Ferreira et al. 2019). Most recently, an immature Allen's Gallinule Porphyrio alleni (an intra-tropical African migrant) was photographed there by L. P. Plotecya on 20 February 2018 ( www.wikiaves.com.br/2897860), constituting another Brazilian first. This gallinule has also been recorded on multiple occasions on Ascension and St Helena in the equatorial Atlantic (Olson 1971, Bourne & Simmons 1998, Rowlands et al. 1998, Prater 2012), as well as far south as South Georgia (Prince & Croxall 1996). Vagrants have possibly also included some overshooting boreal migrants coming from North America such as several Northern Pintails Anas acuta (Antas et al. 1992, Silva e Silva & Olmos 2006, Burgos & Olmos 2013), although the possibility exists that some of these may originate from Eurasia too. Nevertheless, the islands do receive a regular annual passage of North American breeding shorebirds that do not nest in Europe (Olson 1982, Oren 1982, Teixeira et al. 1987, Nacinovic & Teixeira 1989, Soto et al. 2000, Schulz-Neto 2004, Silva e Silva & Olmos 2006). Here, we report some important opportunistic observations made mainly during a visit to Fernando de Noronha by AW, guided by JPFS, on 27–30 March 2018.

Species accounts

SQUACCO HERON Ardeola ralloides

First reported in Brazil on Fernando de Noronha in June 1986 (Teixeira et al. 1987), when a single adult was seen. No further records were made until November–December 2004, when up to five were present at Açude do Xaréu (Silva e Silva & Olmos 2006). Since then, a growing population has been photographed annually since 2008 (Davis 2010, Wikiaves 2018). During March 2019 we had a peak daily count of 22, comprising both adults and immatures, at three different freshwater wetlands and along the coast, where they were observed feeding on crabs on the rocky shoreline; in early August 2019, GMK et al. recorded up to 16 per day. JPFS has observed adults carrying nest material on several occasions, but has yet to prove breeding. The colonisation and breeding by this heron on the islands were predicted by Silva e Silva & Olmos (2006).

Squacco Heron appears to represent a rare example of a successful transatlantic colonisation event, with the first mainland Brazilian record reported in March 2018 (see  www.wikiaves.com.br/2915623), an adult in full breeding plumage, found by J. Amaya, on a lake in Fortaleza, Ceará. The breeding-plumage colours of its bare parts are clearly visible in the photographs, including the bright blue bill ( www.wikiaves.com.br/2916775). D. Almeida (pers. comm.) noted that the individual was very territorial and chased off any small white egrets. We suspect it migrated the relatively short distance of 680 km from Fernando de Noronha, rather than coming directly from Africa, although the latter cannot be discounted. The increasing Fernando de Noronha population may well act as a nucleus to aid the colonisation of suitable habitat on the South American mainland. Two other Old World herons have also colonised the New World: firstly Cattle Egret Bubulcus ibis, but more recently and less spectacularly Little Egret Egretta garzetta. In April 1954 the first Little Egret was found on Barbados (Bond 1966) and breeding was first reported in December 1994, at Graeme Hall Swamp, also on Barbados, the first colony in the Western Hemisphere (Massiah & Frost 1998, Buckley et al. 2009). Since then, the number of sightings in the Caribbean has grown, and in 2008 nesting occurred on Antigua (Kushlan & Prosper 2009). More recently, Little Egret has been recorded with increasing frequency in Trinidad & Tobago, where the species is now present year-round in small numbers (Hayes & White 2001, Kenefick et al. 2019), and has occurred in all three of the Guianas, with at least 18 records in French Guiana and interbreeding with Snowy Egret E. thula reported in Suriname (Ryan 1997, Renaudier & Comité d'Homologation de Guyane 2010, Ottema 2015). In addition, Grey Heron is now effectively resident in the southern Lesser Antilles, principally on Barbados, although there is no evidence of breeding yet (Buckley et al. 2009, Kirwan et al. 2019), and Black-crowned Night Heron Nycticorax n. nycticorax (the Old World race) is known to be nesting on Fernando de Noronha (Silva e Silva & Olmos 2006; pers. obs.).

Figure 1.

Adult Squacco Heron Ardeola ralloides, Fernando de Noronha, Pernambuco, Brazil, March 2018; now a common sight along rocky coasts of the main island and at freshwater pools (Andrew Whittaker)

GREY HERON Ardea cinerea

AW & JPFS encountered an adult on Ilha do Chapéu in the evening of 29 March 2019, perched at the edge of the island in the sun c.300 m away. Subsequently, the bird took off, gaining height as it flew around the coastal inlet, and was photographed as it flew off west. JP was unfamiliar with this Old World species but had almost certainly seen the same bird on 14 March, at Açude do Xaréu, but thought it was a Cocoi Heron A. cocoi. On that occasion no photograph could be taken. However, we subsequently discovered that presumably the same bird had been photographed in the same place on 20 February by L. P. Plotecya ( www.wikiaves.com/2895530). Subsequently, JPFS presumably observed our bird again at the same lake on 1 July and the same bird was in the general area until at least 7 August 2018 (GMK et al.).

Figure 2.

Adult Grey Heron Ardea cinerea, Fernando de Noronha, Pernambuco, Brazil, March 2018; the main field marks separating it from Great Blue Heron A. herodias are the white (vs. cinnamon) carpal joint, yellow bill and white forehead (Andrew Whittaker)

Figure 3.

Adult Grey Heron Ardea cinerea, Fernando de Noronha, Pernambuco, Brazil, March 2018; lacks the cinnamon on the thighs, separating it from Great Blue Heron A. herodias (Andrew Whittaker)

The bird was clearly not a Cocoi Heron given the presence of a distinct white forehead (Fig. 2) and grey neck (unlike Cocoi, which has a white neck). It was distinguished from Great Blue Heron A. herodias in lacking the cinnamon wing bend (Fig. 2) and thighs (Fig. 3) of the latter. Instead these parts are both white in Grey Heron. AW has extensive field experience with Grey Heron in Europe, as well as of Great Blue Heron in the USA.

Great Blue Heron (which is yet to be fully documented in Brazil; Piacentini et al. 2015) is a regular winter visitor in very small numbers to north-west South America, in Colombia, Ecuador and Venezuela (Ridgely & Greenfield 2001, Hilty 2003). Elsewhere, it has been recorded as a vagrant to, among others, the Azores, Spain, UK and the Netherlands (Martínez-Vilalta et al. 2019).

The first published record of Grey Heron in Brazil involved a bird ringed in France in May 1973 and captured in December 1973 at Ourém, Pará, at the mouth of the Amazon (Novaes 1978). Documented Brazilian records remain few, with the second record an immature photographed on Fernando de Noronha, at Açude do Xaréu, in September 2003 (Silva e Silva & Olmos 2006). These authors also noted several other records of large grey Ardea; singles in August 2000, February 2003, November and December 2004. However, as these were only presumed to be Grey Herons, the third definite record was a bird photographed by F. Schunck, also at Açude do Xaréu, in September 2013 ( www.wikiaves.com/1123959). The record reported above becomes the fourth. The chronology of certain records suggests that, contra Silva e Silva & Olmos (2006), this heron is not an especially regular vagrant to Fernando de Noronha.

WOOD SANDPIPER Tringa glareola

On 29 March 2019, at 13.30 h, AW discovered an interesting shorebird on a sludge pool at a sewage treatment plant, which he quickly suspected to be a Wood Sandpiper. AW was aware that this species would be new for Brazil and, due to the light and similarity to other Tringa spp., especially Solitary Sandpiper T. solitaria, knew that he required better views and photographic evidence to confirm the identification. On closer approach, he was able to observe the bird in better light, take notes and photograph it. He could clearly see an obvious white supercilium reaching behind the eye (lacking in Solitary Sandpiper, which has a bold eye-ring), prominently white-spotted upperparts (smaller spots on Solitary), relatively longer yellowish-green legs (vs. greenish) and more obviously spotted and streaked upper breast than Solitary Sandpiper. Figs. 4–5 clearly show all of the characteristics diagnostic of Wood Sandpiper. JPFS & AW observed the bird for another 15 minutes before they had to leave. They returned at 14.45 h, when the bird was roosting on the same sewage pan, but it could not be relocated on the afternoon of 30 March. Overnight weather conditions had been clear and ideal for migration. Further visits by JPFS to the site during April and May were also negative.

Wood Sandpiper breeds in north and central Europe east through Siberia to Anadyrland, Kamchatka and the Commander Islands, as well as in north-east China and, occasionally, on the Aleutian Islands; it winters mainly in tropical and subtropical Africa, and across South and South-East Asia, the Philippines, Indonesia, New Guinea and Australia (van Gils et al. 2019).

Figures 4–5.

Adult Wood Sandpiper Tringa glareola, Fernando de Noronha, Pernambuco, Brazil, March 2018; note the long bold white supercilium (reaching well behind the eye), boldly checkered upperparts, long yellowish-green legs, and prominently marked upper breast (Andrew Whittaker)

The only other documented South American record was on Tobago, in December 1996–February 1997 (Hayes & White 2000, Petersen & McRae 2002, Kenefick & Hayes 2006). There are also nine records in the West Indies: seven from Barbados, all between October and April including one long-stayer, with the first in 1955 (Mazar Barnett & Kirwan 2000, 2002, Ebels 2002, Buckley et al. 2009, N. Amer. Birds 66: 188), and two on Guadeloupe, in September 2000 (Levesque & Jaffard 2002) and September 2014 (N. Amer. Birds 69: 169). Also reported once on Ascension, in October 1963 (Bourne & Simmons 1998).

Howell et al. (2014) noted that Wood Sandpiper records are very rare in the lower 48 states of the USA, with fewer than eight records at the time of compilation, contrasting with nearly 20 records from the Azores since the year 2000, and three records from Bermuda, the first in October 1981 (Amos & Wingate 1983), followed by two in spring, although whether all of these had crossed the Atlantic from east to west is perhaps doubtful.

Common Cuckoo Cuculus canorus

While at the north end of Fernando de Noronha on the afternoon of 27 February 2018, BL encountered an unfamiliar bird at Capela de São Pedro. He managed to photograph it with only a 50 mm lens, as it was obviously a tired migrant (Figs. 6–8). BL sent the photographs to JPFS, who in turn contacted Carlos Goulart. He identified the bird as a Common Cuckoo, a first Brazilian and South American record. JPFS also sent the images to AW, who has ample field experience with the species in Europe and was able to eliminate the faint possibility of a vagrant Oriental Cuckoo C. optatus given the pattern of the undertail-coverts (Fig. 8).

Figs. 6–8, although not high quality, clearly show the distinctive Common Cuckoo jizz, shape, brownish-grey upperparts and white underparts boldly barred black; Fig. 8 also displays its characteristic long-winged and long-tailed, almost raptor-like, appearance in flight. The bird shows substantial rufous-brown feathering admixed with grey on its mantle and wings (Figs. 6–7) confirming that it was a first-year moulting to adult plumage.

Figures 6–7.

Common Cuckoo Cuculus canorus, Fernando de Noronha, Pernambuco, Brazil, February 2018; note long pointed wings and tail, the small amounts of grey plumage already appearing and lack of rufous wash to the upper breast, clearly confirming it to be a first-year male moulting into adult plumage (Breno Lucio)

Figure 8.

Common Cuckoo Cuculus canorus, Fernando de Noronha, Pernambuco, Brazil, February 2018; the pure white undertail-coverts indicate the present species and eliminate Oriental Cuckoo Cuculus optatus in which these feathers are buff (Breno Lucio)

The nominate form has a rufous morph found only in females. With good views female plumage can be separated from that of males by a small area of rufous wash on the upper breast extending to the neck-sides. Fig. 6 clearly demonstrates the absence of this feature, confirming the bird as a male. Also, on closer inspection, it is possible to see some grey feathers moulting in amongst the dominant rufous on its wings, mantle (Fig. 7) and tail confirming the bird as a first-year moulting into breeding plumage.

Common Cuckoo has four subspecies: C. c. canorus breeds from Ireland to Kamchatka and Japan, with western populations wintering in equatorial Africa; C. c. bangsi breeds in Iberia, the Balearics and north-west Africa, and probably winters in Africa south of the equator; C. c. subtelephonus breeds in Transcaspia to west Xinjiang (China) and central Mongolia, and south to Iran and Afghanistan, wintering in India; and C. c. bakeri breeds in northern India to northern Thailand and Indochina, south and east China, and winters in India and South-East Asia (Erritzøe et al. 2012).

The Fernando de Noronha record presumably refers to nominate canorus which is a long-distance migrant, with western populations migrating between Europe and equatorial Africa, in the Congo rainforest bloc. This race has already been recorded as a vagrant on Ascension (Bourne & Simmons 1998, Erritzøe et al. 2012).

The first vagrant Common Cuckoo for the Western Hemisphere was collected on Barbados in November 1958, where another was observed in November 2014 (Kirwan et al. 2019). These are the only other Neotropical occurrences, but there are two mainland North American records, an adult at Martha's Vineyard, Massachusetts, in May 1981, and a juvenile at Watsonville, California, in September–October 2012 (Howell et al. 2014). It is also a rare and infrequently recorded visitor to the western Aleutians in late spring and early summer, with all records involving the nominate (Howell et al. 2014).

Ongoing work by the British Trust for Ornithology using satellite-tags has, since May 2011, tracked 49 males and one female of the British breeding population of Common Cuckoo. UK cuckoos take different routes in spring and autumn between Europe and Africa. Irrespective of whether they move south via Spain, Italy or even further east, all of them head to West and Central Africa, where they mainly winter in and around the Congo rainforest bloc. In spring they mostly return overland across the Sahara to Europe, however others fly almost due west along the southern edge of the Sahara to the coast, then head north to southern Europe (Hewson et al. 2016;  https://www.bto.org/science/migration/tracking-studies/cuckoo-tracking). This could explain the appearance of a vagrant on Fernando de Noronha at this season; it presumably overshot the west coast of Africa and instead headed out into the Atlantic, possibly aided by strong tail winds, before finally making landfall in Brazil.

Recent satellite tracking of another subspecies, C. c. subtelephonus breeding around Beijing, China, led to the discovery that these birds make a non-stop flight of 3,300 km in autumn, crossing the Indian Ocean between the west coast of India to East Africa, making landfall in Somalia then moving south to winter in Tanzania ( https://www.bto.org/science/migration/tracking-studies/cuckoo-tracking/about/international-projects). In spring, the return sea crossing follows a similar route. This confirms that Common Cuckoo is easily capable of a non-stop crossing of the Atlantic between West Africa and South America, which distance is less than 2,000 km. It also explains other reports of long-distance vagrancy by the nominate race, as far as Greenland, Iceland and the Azores (Erritzøe et al. 2012).

Discussion

Our understanding of avian transatlantic vagrancy to South America is still very poorly understood. Both Common Cuckoo and Wood Sandpiper are long-distance Palearctic migrants that move between breeding grounds in northern Europe and wintering areas in sub-Saharan Africa, even as far as South Africa in the case of Tringa glareola. This makes both likely candidates for vagrancy to north-east South America, especially Fernando de Noronha, where the chances of them being found are greater than on the even more under-watched coasts of mainland Brazil. Their arrival probably is due to several related factors combined: inexperience, especially among non-adults; storms; and especially wind-drift in the westerly trade winds that are commoner in more southerly regions off the Atlantic coast of Africa.

Despite the growing number of visiting photographers and birders, Fernando de Noronha is still under-watched and most Palearctic vagrants are probably missed, especially any passerines, due to the very dense vegetation covering much of the island. The sewage treatment ponds on Fernando de Noronha should, almost certainly, yield other new Palearctic shorebirds for Brazil if birders and photographers check them on a regular basis.

Observers in north-eastern and eastern Brazil should be aware of the possibility of finding other transatlantic vagrants, usually Eurasian–African migrants, but potentially intra-tropical African landbird migrants too. In Tables 1–2 we list 47 potential additions to the Brazilian avifauna that have already been recorded on the mid-Atlantic islands of Ascension, St Helena and the Tristan da Cunha group, or in the West Indies, more exceptionally elsewhere in South America, all of which are most likely to be encountered on either Fernando de Noronha or the São Pedro and São Paulo archipelago, rather than the Brazilian mainland. Transatlantic vagrancy is already fairly well documented from French Guiana, the southern West Indies and Trinidad & Tobago (Ebels 2002, Kenefick & Hayes 2006, Restall et al. 2006, Buckley et al. 2009, Kirwan et al. 2019). The majority of the Palearctic vagrants reported in Brazil on Fernando de Noronha and São Pedro e São Paulo have also been recorded in the Caribbean (including Trinidad & Tobago) or the South American mainland in French Guiana. As this list of vagrants already includes one of our two new Brazilian records, we briefly discuss other Brazilian first records from the offshore islands also documented from these other regions. However, we omit Little Egret as it is one of the most frequently recorded Palearctic vagrants, with many records from the West Indies (Kirwan et al. 2019), Trinidad & Tobago (Hayes & White 2001), the Guianas (Haverschmidt 1983, Murphy 1992, Renaudier & Comité d'Homologation de Guyane 2010, Claessens & Comité d'Homologation de Guyane 2015), and even the USA (Murphy 1992).

Eurasian Spoonbill Platalea leucorodia.—First record on Tobago in early November 1986 (Hayes & White 2000), followed by one on Trinidad in November 2010 (Kenefick 2012) and, in Brazil, an immature photographed on Fernando de Noronha in early December 1996 (Schulz-Neto 1998) with another photographed there in January–February 1999 (K. Hazevoet in Ebels 2002). Caribbean records (some involving multiple individuals) are from Antigua, St Lucia and Barbados, all since 2007 (Buckley et al. 2009, Kirwan et al. 2019).

Grey Heron Ardea cinerea.—First record in the Caribbean in September 1959 on Montserrat and has been resident on Barbados since 1997, with multiple documented records north to St Kitts, and French-ringed birds recovered on Martinique and Montserrat (Bond 1962, Buckley et al. 2009, Kirwan et al. 2019). Also a French-ringed individual recovered on Trinidad in August 1959, followed by another nine records in Trinidad & Tobago by 2010 (Badouin-Bodin 1960, ffrench & Kenefick 2003, Kenefick 2012), as well as those from Fernando de Noronha mentioned above.

Purple Heron Ardea purpurea.—First New World record an ‘immature’ on Fernando de Noronha in June 1986 (Teixeira et al. 1987), followed by a long-staying bird in the same place, in March 2017–April 2018, which was photographed (Ferreira et al. 2019). Six West Indian records, all since autumn 1998, most involving first-year birds, between September and April (Kirwan et al. 2019) and three from Trinidad & Tobago (Kenefick 2012, Kenefick et al. 2019); also recorded once on St Helena, October 2009 (Beard 2012), with several records from Ascension (Bourne & Simmons 1998).

Western Reef Egret Egretta gularis.—First record in the Caribbean on Barbados (June–July 1975), where recorded at least nine times subsequently, with other reports from Puerto Rico (first September 1999), St Lucia (February 1984, January 1985), the Grenadines (Mustique, February 2004), and a possible sight record in Cuba (Buckley et al. 2009, Kirwan et al. 2019). South American records: Trinidad, January 1986 (Murphy & Nana 1987), December 2000–January 2002 (Ebels 2002) and December 2014–June 2015 (Kenefick et al. 2019), and two in Brazil, both on Fernando de Noronha, a dark morph photographed in early December 1996 (Schulz-Neto 2004) and a white-morph photographed in late November 2004 (Silva e Silva & Olmos 2006).

Black Kite Milvus migrans.—First report in the Neotropics on Dominica in April 1999 (N. Amer. Birds 57: 132), since when there have been at least five additional records from the Bahamas, British Virgin Islands, Guadeloupe and Barbados (Kirwan et al. 2019), and one on Trinidad in December 2014 (Kenefick et al. 2019). The first Brazilian record was on the São Pedro e São Paulo archipelago, in April–May 2014 (Nunes et al. 2014).

Eurasian Kestrel Falco tinnunculus.—Two Caribbean records, on Martinique in December 1959 (Pinchon & Vaurie 1961) and Guadeloupe in April 2009 (Kirwan et al. 2019), while the first South American record was a subadult male present for ten days in French Guiana in Mar 1991 (LeDreff & Raynaud 1993). This was followed by an immature female photographed on Trinidad in December 2003–January 2004 (Kenefick & Hayes 2006), two records in Brazil, both on the São Pedro e São Paulo archipelago, the first in January 2005 (Bencke et al. 2005, Santana & Pinheiro 2010), and another five records in French Guiana, all between late December and late March (Renaudier & Comité d'Homologation de Guyane 2010, Claessens & Comité d'Homologation de Guyane 2015).

TABLE 1

List of Old World vagrants recorded on the mid-South Atlantic Ocean British Overseas Territory of St Helena (15°57′S, 05°42′W), Ascension (07°57′S, 14°22′W) and Tristan da Cunha (37°15′S, 12°30′W), but not yet recorded in Brazil. St Helena, Ascension and Tristan da Cunha are situated 1,950 km, 1,500 km and 2,432 km from the west African coast and 4,000 km, 2,250 km and 4,046 km from the nearest points of mainland South America, respectively. Unless otherwise stated information pertaining to occurrences on St Helena are taken from Rowlands et al. (1998) and Prater (2012), Ascension from Bourne & Simmons (1998) and Tristan da Cunha from Dowsett & Forbes-Watson (1993). Species also represented in the New World, sometimes by separate races, are omitted, even if there is evidence that the individuals concerned wandered from the Old World, e.g. Black-crowned Night Heron Nycticorax n. nycticorax has been recorded on St Helena. Where additional records are available from the Caribbean or elsewhere in the Neotropics, these are also listed in the comments column.

TABLE 2

List of Old World vagrants, or species whose provenance is potentially transatlantic, recorded in the West Indies or South America, but yet to be definitely recorded on any of the mid-Atlantic islands or in Brazil; seabirds are omitted, as are a suite of landbirds reported from Cuba that appear very unlikely to have reached the Caribbean in a wild state (Kirwan et al. 2019: 375–376). These are confirmed by either ringing recoveries of European origin, specimens or photographs. One species (Lesser Sand Plover Charadrius mongolus) has been recorded only in mainland South America. Most or all records of Northern Wheatear Oenanthe oenanthe in the region might involve birds migrating from their North American breeding grounds to their wintering areas in Africa, but the capacity for birds breeding in Europe that also winter in Africa to occur as vagrants in Brazil clearly exists. Glossy Ibis Plegadis falcinellus occurs in northern South America (Venezuela), but there is clear evidence of vagrancy, perhaps increasing (Kirwan et al. 2019), from the Old World to the Caribbean, and we consider that there is a clearly greater likelihood of the species wandering to the Brazil through transatlantic wandering.

Final remarks

Transatlantic vagrancy of Palearctic migrants to South America and the Caribbean has been a relatively little-recognised and potentially under-recorded phenomenon, although as evidenced by Tables 1–2 it clearly occurs fairly regularly. By documenting two new Palearctic vagrants and providing a list of potential future Old World vagrants, this should encourage observers to be alert to the possibility of other Palearctic species occurring in Brazil and perhaps other South American countries too.

A few of these ‘transatlantic’ vagrants may in fact not reach South America by crossing the Atlantic, but instead arrive by flying over North America from north-east Asia. Some predominantly Palearctic species also nest in Alaska and Greenland, e.g. Common Ringed Plover Charadrius hiaticula and Northern Wheatear Oenanthe oenanthe, both of which have already been recorded in the Neotropics. However, other well-established principally Palearctic breeders such as Bluethroat Luscinia svecica and Eastern Yellow Wagtail Motacilla tschutschensis (Kessel & Gibson 1978, Kessel 1989, Renner & McCaffery 2006) and very rare breeders like Red-necked Stint Calidris ruficollis (DeCicco et al. 2013) and Red-throated Pipit Anthus cervinus (West 2008) have yet to be recorded in north-east South America, although the latter has been recorded as far south as north-west Ecuador (Brinkhuizen et al. 2010) and C. ruficollis has been claimed in coastal Peru (Hughes 1988, Schulenberg et al. 2007).

It will be nigh-on impossible to confirm how many ship-assisted passages occur. An example was a Redwing Turdus iliacus found aboard a seismic research vessel 150 km off the coast of Espírito Santo, Brazil, in December 2001 (Brito et al. 2013). On the other hand, as demonstrated by one of the most unexpected and most remarkable vagrants to the Americas, a species yet to be reported in Europe, Siberian Flycatcher Muscicapa sibirica, was collected on Bermuda in September 1980 (Wingate 1983), illustrating the potential for even eastern Palearctic migrants to appear in the western Atlantic.