Red Sea Swallow

Description 

Also known as the Red Sea Cliff Swallow 

14 cm 

Blue crown  

Blackish/dark brown lores, forehead, nape, sides of neck, and mantle with a blue gloss  

Grey rump  

White chin   

Bluish-black upper breast and throat   

Base of lower neck and mantle feathers are white  

Sides of neck and forecrown feathers have a small pale grey patch  

Rump feathers are dark grey with white bases and warm buff brown fringes 

Dark glossy brown uppertail-coverts  

Dark brown wings that are slightly glossy  

Blackish-brown square tail  

White spot on chin 

Rest of underparts are white  

Lower breast and belly are silky white that is demarcated from the upper breast by a narrow warm buff line  

Glossy deep blue back 

Pale grey vent that is strongly washed pale orange  

Proximal undertail coverts are pale grey with the lateral ones being glossy black or bluish black with pale grey tips  

Silky white underwing-coverts  

Pale orange axillaries  

Bill, legs, feet, and claws are black (Fry and Smith, 1985) 

Habitat 

This species’ habitat is unknown. However, given the fact that this bird appears to be a cliff swallow, one can assume that it might be open grassland, mountainous areas, and cliffs since they are the preferred habitats of other members of the Petrochelidon genus

Other Information 

Movement unknown  

Diet unknown (probably insects) 

Vocal behavior unknown 

Breeding behavior unknown 

Range unknown (Birds of the World) 

Life span- 4 years (IUCN Red List) 

This species is listed as Data Deficient by the IUCN that did its last assessment in 2016. This is because only one specimen has been found and next to nothing is known about its range, population, behavior, preferred habitat, etc. (IUCN Red List).

The only reason we know of the Red Sea Swallow’s existence is because C.H Fry and D.A Smith during an ornithological study of Sanganeb accidentally found a dead swallow between a disused water tank and the granite tower of the lighthouse they were staying at on May 9, 1984. They inferred that the decomposing corpse had struck the light 40 m above and fell in a crevice that protected it from predators and scavengers. Although they were only able to preserve the wings and the tail for study, they took a photo of the corpse.  

Fry originally described the bird as a subspecies of the South African Cliff Swallow (Petrochelidon spilodera). However, upon closer analysis he realized that this bird was a completely different species that separated her from this species. The bird had a blue crown (not dark brown), blackish lores and forehead (not buffy-orange), a grey rump (not buffy white or pale rufous), a white chin (not pale rufous), a different white chin spot, and a bluish-black upper breast and throat (not pale rufous). As a result of these distinguishing characteristics, Fry named the swallow the Red Sea Cliff Swallow or Hirundeo perdita.  

After studying juvenile South African Cliff Swallows and their plumage, Fry and Smith concluded that the specimen was a 4-month-old adult due to the freshly molted and worn feathers in the rump and the new feathers in the uppertail-coverts. This suggested that the bird was going through an incomplete pre-breeding molt and was about to breed but when she crashed into the lighthouse.  

Despite its different traits, Fry and Smith could not help noticing how similar the specimen was to a South African Cliff Swallow. They admit that this species is variable in terms of the black speckling on the throat ranging from buff to black and the degree of rufous striping on the breast and belly that ranges from unstriped to heavily striped. Furthermore, freshly molted South African Cliff Swallows returning to South Africa to breed have blue-black crowns that become brown with wear with their tertials having broad buff edges that wear off after 6 weeks. The specimen also had similar wing measurements, tail characteristics, overall size, bill length, and width to South African Cliff Swallow specimens. As a result, they proposed the possibility that the two might belong to the same complex. 

They ruled out other species such as Preuss’s Cliff Swallow (Petrochelidon preussi) in east Africa, the Red-Throated Cliff Swallow (Petrochelidon rufigula), and the South African Cliff Swallow in southern Africa since the area where the specimen was found was far away from their breeding ranges (3,600 and 4,650 km). They theorize that, when it was alive, the specimen was probably a migrant or vagrant that was heading towards its breeding grounds in the Red Sea Hills of Sudan or Ethiopia.  (Fry and Smith, 1985). 

Besides this one specimen, the Red Sea Swallow has not been seen or heard since 1984. Some speculate that in addition to the Red Sea Hills in Sudan, Ethiopia, or Eritrea that other potential breeding grounds could include the coastal hills in western Saudi Arabia north of Jeddah (Birds of the World). 

When unidentified swallows were seen in Ethiopia between the years 1988-1994, ornithologists were hoping they were Red Sea Swallows. According to observers, these swallows had the following characteristics: 

1. Small to medium-sized and stocky  

2. Shallowly forked tail with a notch that appeared almost square-ended when closed and a shallow fork when spread  

3. Wing shape and flight action were similar to the African Rock Martin (Ptyonoprogne fuligula) with a fluttering flight action with episodes of gliding and turns in between. 

4. These birds appeared in the lower elements of mixed flocks that fed over grassland at the edge of a gorge or over a cliff in the early morning moving up and down a cliff face catching insects  

5. Upperparts, crown, nape, sides of head, and neck were blackish or blue-black with a blue gloss on the wing coverts and mantle that extended to the crown 

6. No rufous was seen on any part of the body  

7. Sides of throat were dark with a pale center  

8. Throat, chin, and upper breast were pale with a greyish-buff smudging at the sides of the breast that formed an incomplete breastband  

9. Whitish breast, belly, and flanks with a buffish or pale rufous wash  

10. Underwing-coverts were whitish washed with pale rufous or buff that contrasted with the dark undersides to primaries and secondaries reminding one of Eurasian Swallows (Hirundo rustica)   

11. Pale, square rufous rump  

12. Tail dark above and below with no pale mirror spots    

13. Cheeks and sides of neck were dark that extended down and restricted the pale, whitish throat to a central area  

14. Rest of underparts were dirty white with a buffy tinge  

15. Dark flight feathers  

Based on these characteristics, observers believed that the birds they saw were cliff swallows. Their rufous rumps, shallowly-forked tails, stocky appearance, and fluttering action reminded them of American Cliff Swallows (Petrochelidon pyrrhonata) even though no cliff swallows have ever been identified in Ethiopia. After comparing what they saw with four species of cliff swallows in Africa, they concluded that this swallow was a new species. The lack of tail spots is a feature that is only seen in the South African Cliff Swallow and the Red Sea Swallow. Preuss’s Cliff Swallow and the Eastern Red-Rumped Swallow (Cecropis daurica) are smaller and have different traits. What is interesting is that they also ruled out the Red Sea Swallow. The major differences between the Red Sea Swallow and the unidentified swallows seen over Ethiopia was that the latter had a pinkish buff or rufous rump instead of dark grey with white fringes and a pale throat and dusky-buff partial breast band instead of a black throat with a pale chin spot. 

In a similar vein to the Red Sea Swallow, observers noted the resemblance between the swallows over Ethiopia and the South African Cliff Swallow. What differentiates the mysterious swallows from this species is the lack of rufous on the forehead and lores and the deep, glossy black head and neck. South African Cliff Swallows show white markings on the mantle that did not show on the mysterious swallows and had a different pattern on their underparts. Could a small flock of South African Cliff Swallows have made its way 2,600 km northeast of its known breeding range? Observers saw this is unlikely since this species is known to breed between September and March which makes small parties moving away from their breeding range unlikely.  

They conclude that the mysterious swallows are a new species that is closely related to South African Cliff Swallow and might be conspecific with this bird. They admit that there might be a link between the Red Sea Swallow and this unidentified species but they deny the possibility that the two birds could be one and the same (Madge and Redman, 1989). 

Possible breeding areas proposed by observers for the unidentified swallows and the Red Sea Swallow include the hills of the Red Sea Coast in western Saudi Arabia north of Jeddah. 

The unidentified swallows were found at the following sites in Ethiopia: 

Kereyou Lodge, Awash National Park 

On November 11 and 12, 1988, while leading a birdwatching tour, S.C Madge and N.J Redman encountered a group of six unidentified cliff swallows 50 m from the Kereyou Lodge at the Awash National Park. Madge first noticed the birds when he was examining a mixed flock that was composed of Eurasian Swallows, Lesser Striped Swallows (Cecropis abyssinica), Eastern Red-Rumped Swallows, and House Martins (Delichon urbica) over the edges of grassland near a gorge west of the lodge. They also saw two birds flying over a grassland three meters away from the original site. The birds they saw matched the description of two strange pale-rumped swallows D.A Smith saw when he was observing the migration of Eurasian Swallows in 1983 just before discovering the first specimen of the Red Sea Swallow species. He saw them fly over the Red Sea towards Jeddah. 

On December 3, almost one month later, a group of English birdwatchers found three mysterious swallows in the same area (Madge and Redman, 1989). 

On September 18, 1993, J.D Atkins and W.G Harvey observed 12 unidentified cliff swallows for half an hour (9:30-10:00 a.m.) feeding along the western cliff faces of a small gorge running north from the main Awash river gorge close to Kereyou Lodge in the Awash National Park. They mostly flew below the rim of the gorge and occasionally moved to the grassland and scrub beyond the rim sometimes joining other species such as Eurasian Swallows, Lesser Striped Swallows, Eastern Red-Rumped Swallows, African Rock Martins (Petrochelidon fuligula), House Martins, Sand Martins (Riparia riparia) and Alpine Swifts (Tachymarptis melba). These swallows were smaller with more triangular wings and a short, notched tail. They flew like martins with periods of gliding, sharp turns, and fluttering along a short flight path that contrasted with the longer, steadier, and sweeping glides of other swallow species. They also had the same physical characteristics as the swallows observed by Madge and Redman five years earlier. These swallows never came closer than 30 m to the lodge.  

Gibe 

On October 18, 1993, Atkins spotted a swallow of the same description near Gibe over grassland close to the Gibe river gorge. 

Jimma 

On March 24, 1994, J.H Harjula saw one of these swallows near Jimma. 

Fantalle Mountain  

One year later on September 25, 1994, another group of unidentified swallows were observed for five minutes at 1 p.m. by Atkins, Harvey, and Harjula. They flew along the inner rim of the northern wall of the crater of Fantalle Mountain 25 km from the sighting at Kereyou Lodge. They were seen alongside two Eastern Red-Rumped Swallows. These swallows were distinguished by their flight pattern, the absence of a chestnut nape, dark cheeks and sides of throat, lack of tail-streamers, and smaller size (Atkins and Harvey, 1994). 

Lake Langano 

On November 30, 1988, a group of English birdwatchers found a large flock (20-24) of mysterious swallows feeding around the cliffs by the western shore of Lake Langano in the Rift Valley 180 km southwest of Awash National Park (Madge and Redman, 1989).  

These encounters mark the only times when these mysterious swallows have been spotted in Ethiopia. The fact that they have never been seen again only deepens the mystery not only surrounding this unidentified species of cliff swallow in Ethiopia but also that of the Red Sea Swallow. 

The Red Sea Swallow’s mysterious origins has only incited controversy surrounding the species’ identity since 1984. 

Is the Red Sea Swallow an aberrant South African Cliff Swallow? 

Some experts have suggested this possibility. However, proponents of this theory have to ask the question: If the Red Sea Swallow is an aberrant member of this species, what was she doing hundreds of kilometers away from the species’ known breeding areas? Fry and Smith note there was a storm near Port Sudan when they were conducting their ornithological research. Could a storm have blown this swallow off course into the lighthouse? If so, how do you explain the strange morphological features? Even Fry and Smith, after studying many South African Cliff Swallows, were not able to explain away these features based on the variation of the species (Fry and Smith, 1985). 

Is the Red Sea Swallow a hybrid? 

Some experts have proposed this theory and some have gone further to claim that this bird is not a distinct species at all. However, without more information on this species it is next to impossible to prove this theory (Vuilleumier et al., 1992). The only thing that can be done is do a DNA analysis on either the wings or tail of the only known specimen. 

Is the Red Sea Swallow a vagrant/migrant? 

If the specimen found was indeed a vagrant/migrant, where did she come from? While the popular theories point to Sudan, Ethiopia, Eritrea, and Saudi Arabia, the truth is this swallow could have come from anywhere. A storm could have blown this swallow off course from any direction. Unless other members of this species are found, we will remain in the dark about this species’ origins. 

Conduct a DNA analysis on either the wings or tail of the only known specimen recovered by Fry and Smith to see if this bird really is a distinct species.

In 2011, Tom Jenner and his brother, Adam, investigated the Red Sea Hills in Sudan. They covered the highest plateau around Arkowit, the lowlands, and the dry hills north of Port Sudan near the lighthouse where the only specimen of the Red Sea Swallow was found. They did not see any swallows in the hills, not even Rock Martins, despite there being suitable habitat in the area. They saw migrating Barn Swallows (Hirundo rustica), House Martins, and Sand Martins on the coastal plains as well as some Rock Martins at Arkowit. This suggests that the Red Sea Swallow might be there and that the Jenner brothers just missed them. This is compounded by the fact that these swallows could have come from anywhere. They suggest that the hills near Jeddah in Saudi Arabia would be a good place to look. Nonetheless, they admit that there's still a chance that the Red Sea Swallow might be at Port Sudan (Birding Sudan).

Order: Passeriformes 

Family: Hirundinidae 

Genus: Petrochelidon 

Species: Petrochelidon perdita* 

*This species was originally described as Hirundo perdita before it was changed.