Itombwe Nightjar

This bird is known only from the Itombwe Mountains of eastern Democratic Republic of the Congo. The voice of this presumably forest nightjar is unknown, as it was described to science 35 years after the lone specimen was collected (1955). However, unraveling the identity of a mysterious nightjar vocalization across Central Africa may be the key to solving this puzzle.

Description

Also known as Prigogine's Nightjar

19 cm

Underparts and wing coverts are brown, speckled and spotted dark brown, tawny and buff

No nuchal collar (Data Zone-Birdlife International)

Breast is brown spotted and barred tawny and buff

Belly and flanks are paler than breast, barred brown with a small tawny spot on second, third, and fourth outermost primaries

Outermost tail feathers have narrow whitish tips

Other tail feathers have narrower buffish or tawny tips

Bill is blackish

Stiff feathers

Small tail/wing proportion

Broad head

Short, rictal bristles

Speckled plumage

Wing length- 164 mm

Tail length- 89 mm

This is a nightjar with the shortest tail in Africa

Wing tips reach end of tail

Speckled brown and rufous

Pale speckles in the plumage all over (especially on crown, rump, and upper tail coverts)

Distinct black blotches all over

Feathers of coverts are rufous and barred black

Scapular feathers marked with black blotches on center and pale buffish, some almost look like white dots

Feathers have rufous speckles

Stomach feathers are rufous brown with all feathers barred blackish

Large buffish spots on lower breast, belly and undertail which are buff, barred blackish in a wider pattern than on other parts of the plumage

Undertail feathers are stiff

Outer primaries are dark brown with few rufous spots

Inner primaries are barred sparingly with rufous spots

Underwing coverts are rufous and barred blackish brown

Central rectrices are dark brown and barred with an irregular pattern in buff

Throat has a buffish white patch (10 mm) on each side with some buffish feathers laterally

Tail- 89 mm

Tarsus- 14 mm (Louette, 1990)

Legs and feet are a reddish brown (Birds of the World)

Looks similar in appearance to the Fiery-Necked Nightjar (Caprimulgus pectoralis)

Descriptions come from a lone female specimen found at Malenge in the Itombwe Mountains in the Belgian Congo (now the Democratic Republic of the Congo) in 1955

Life span 5.6 years

Based on the few observations of this mysterious nightjar, this species may prefer a forest habitat with a broken canopy (IUCN Red List)

This nightjar was not described as a separate species until Michel Louette examined the lone specimen in 1990 at the Koninklijk Museum voor Midden-Afrika, Tervuren, Belgium (Louette, 1990)

Many experts, such as Vuilleumier et al. (1992), concur with Louette in that the Itombwe Nightjar is a distinct species and does not belong to a superspecies

In several languages, the Itombwe Nightjar is known as Prigogine's nightjar after the collector of the specimen. However, in Dutch, the species' name is Louettes nachtswaluw or "Louette's Nightjar" who was the one who first described the Itombwe Nightjar as a new species in 1990.

Range

There is a lot that is unknown about the Itombwe Nightjar's range. It is speculated that the species lives in the Itombwe Mountains since that was where the lone specimen was found at 1,280 m in this area. However, sound recordings of a mysterious forest nightjar in Southeast Cameroon, the north of the Democratic Republic of the Congo, and Gabon suggest that this species has a much wider range.

Other Information

This species' habitat, movement, foraging methods, vocal behavior, and breeding habits are unknown (Birds of the World)

The Itombwe Nightjar is listed as endangered by the IUCN. While much is unknown about the species' population, it is assumed to be declining due to its narrow range and the rising degree of habitat loss in the region. The IUCN will reassess this species if it is confirmed that the Itombwe Nightjar is present in a wider range beyond the Itombwe Mountains as some ornithologists have contested based on the mysterious recordings made in the late 1990s (IUCN Red List).

Known with certainty from only a single specimen, which was collected in the Itombwe Mountains of eastern Democratic Republic of the Congo (August 1955; RMCA 78975).

Royal Museum for Central Africa, Belgium.

The original collector of the only specimen, Alexander Prigogine, thought that it was an immature Bate's Nightjar. After an in-depth investigation by Michel Louette at the Royal Museum for Central Africa, Belgium, this specimen turned out to be a new species. When Louette first described the species in 1990, he noticed that the specimen was not closely related to any other nightjar on the African continent (such as Bate's Nightjar and the Brown Nightjar). While some may be tempted to put the Itombwe Nightjar in the same taxon that includes other African nightjars such as the Red-Necked Nightjar (Caprimulgus ruficollis), the Mountain Nightjar (Caprimulgus poliocephalus), the Fiery-Necked Nightjar (Caprimulgus pectoralis), the Black-Shouldered Nightjar (Caprimulgus nigriscapularis), and the Abyssinian Nightjar (Caprimulgus ruwenzorii), Louette concludes that the Itombwe Nightjar is not a relative of this group due to the distinct differences this bird has vis-à-vis other nightjars in Africa (such as the rufous feathers, speckles on the plumage, broad head, and hard plumage). He goes further and argues that this bird is not a hybrid and has no relatives among known species of nightjars. He concludes that the Itombwe Nightjar might behave like a nighthawk which forages actively and avoids flying among thick vegetation. While the specimen was found in a transition forest, Louette thinks it is likely that the bird could have a wider range of environments that includes lowlands forests and montane areas (Louette, 1990).

Sounds of a Mysterious Nightjar

Since the species was first described by Michel Louette in 1990, there have been no confirmed sightings of the Itombwe Nightjar. However, over the years, researchers from the field have come forward hearing sounds of an unidentified, mysterious forest nightjar. They are convinced that these sounds are none other than the Itombwe Nightjar.

Here are the places where the mysterious forest nightjar was heard between 1985-1998:

M'Passa, Invindo, Gabon (April-May 1985)

Odzala National Park, Democratic Republic of the Congo (April 1994)

Itombwe, eastern Democratic Republic of the Congo (April 1996)

Nouabalé-Ndoki National Park, northern Democratic Republic of the Congo (April 1996 & May 1997)

Lobéké Faunal Reserve, Cameroon (December 1997, January 1998)

If this mysterious species is indeed the Itombwe Nightjar, these encounters suggest that this species has a much wider range than previously thought that encompasses the border of three African countries including the Democratic Republic of the Congo (especially the regions of Itombwe, Kinshasa, and Brazzaville), Gabon, and Cameroon (Butchart, 2007).

The M'Passa Encounter (April-May 1985)

In April-May 1985, field researchers in Gabon heard the song of a mysterious nightjar. Due to the acoustic similarities between the song of the mysterious nightjar with the Swamp Nightjar (Caprimulgus natalensis), they confused the former with the latter. The bird sung at riverside clearings near M'Passa in the region of Invindo (Butchart, 2007).

The Dowsett-Lemaire Encounter at Odzala National Park (April 1994)

On the night of April 3, 1994, Françoise Dowsett-Lemaire heard an unidentified nightjar in Odzala National Park in the Democratic Republic of the Congo near the Ndoki camp. She noticed that the song was similar to a Swamp Nightjar but with a different timbre. It took place near the Lékénie River in a mostly evergreen, swampy forest. Even though Swamp Nightjars are known to like these types of environments along with dry grasslands, dambos, and wet grasslands, Dowsett-Lemaire was convinced that this was not a Swamp Nightjar and was a wandering member of a new species of nightjar looking for a new territory. This would only be the first of several encounters she would have with this enigmatic bird.

The Dowsett-Lemaire Encounter at Nouabalé-Ndoki (April 1996)

Between April 4-6, 1996, Dowsett-Lemaire had three more encounters with the same mysterious nightjar she first encountered in Odzala. Except this time, these encounters took place at Nouabalé-Ndoki National Park in the north of the Democratic Republic of the Congo. This park is known for its semi-evergreen forest with an open canopy, is located at an altitude of 350 m, and has a 20 m overstorey. On the night of April 4, she heard the nightjar sing and made a successful recording. The next night, she played the recording and received a response. The bird approached her before crossing a narrow track. The bird sang on the other side before giving a harsh, rolled call. Dowsett-Lemaire described this call as being a rek-rek-rek sound. She noticed that there was a pair of these birds in the area and that one of them flew around her. In the shadows, they appeared small and stocky. She describes the song she heard on the night of April 5 as a series of staccato notes lasting between 4-12 seconds each. The song was sung between 10-20 m as the bird moved around. On the night of April 6, Dowsett-Lemaire saw another mysterious nightjar fly over a track but there was no singing (Dowsett-Lemaire, 2009).

The Dowsett Encounter at Lobéké (April 1997)

From April 13-25, 1997, Françoise Dowsett-Lemaire and her husband, R.J Dowsett, conducted a survey of the Lobéké Faunal Reserve in southeastern Cameroon. The reserve has an altitude range between 336-750 m where the dominant habitat is a semi-evergreen forest with an open canopy dotted with areas of evergreen forests with closed canopies as well as marshy areas. On the night of April 21, 1997, the Dowsetts heard a strange song 1.2 km east of the Boulou camp in the reserve before 9 p.m. The mysterious bird sang in the moonlight for more than 20 minutes in dense vegetation 20 m off the ground. They described the song as a dry staccato that was similar to that of the Swamp Nightjar but with a faster pace, lower pitch, and a different timbre (Dowsett-Lemaire and Dowsett, 1998). When spectrographed, was identical to another recording of an unidentified nightjar that was recorded previously near Ndoki camp by Françoise Dowsett-Lemaire on two separate occasions (1996 and 1997). The Dowsetts did a playback of the recording made by Thomas Butynski when he also encountered an unidentified bird when he was in Itombue in the eastern part of the Democratic Republic of the Congo in 1996. The mysterious bird responded to the playback and came closer. She sang for 15 minutes at a height between 15-20 m in dense vegetation. Afterwards, the bird gave off a dry rek-rek, flew across the road, sang again, flew further away, and sang once more but barely audible. To this day, the Dowsetts believe that the bird was not endemic to the reserve and may have been a wanderer (Dowsett-Lemaire, 2009). They are convinced that it is a third species of forest nightjar, the Itombwe Nightjar. The other two species are Bate's Nightjar (Caprimulgus batesi) and the Brown Nightjar (Caprimulgus binotatus). Even though both of these species are also found in Lobéké, the Dowsetts rest firm in their conviction that what they heard that night was the Itombwe Nightjar. They further state that, "Lobéké may prove to be the most important site anywhere in Cameroon/Gabon for the preservation of range-restricted species." Range-restricted species like the Itombue Nightjar.

The Dowsett Encounter at Nouabalé-Ndoki (April-May 1997)

At the end of April and the beginning of May same year after ending their survey in Lobéké, the Dowsetts returned to Nouabalé-Ndoki National Park in the Democratic Republic of the Congo where they heard three unidentified nightjars along a 25 km stretch of track connecting Bomassa to Ndoki. They were heard off-track in a dense Marantaceae understorey near Ndoki camp. The birds appeared small and dark when seen in flight at dusk. They sang spontaneously for long periods at high altitudes in dense vegetation and in lower canopy of an Autranella at a height of 30 m. When they played the Butynski tape made in Itombue, the birds began to sing louder and higher. They sung a dry staccato that reminded them of the song of a Swamp Nightjar but with a lower pitch and a different timbre. Some songs lasted 3 minutes and 10 seconds. The tempo was 11 notes in 10 seconds. After they were done, they flew nearby briefly to give a rek-rek call before disappearing from earshot. They attempted to catch the nightjar using mist-nets without success (Dowsett-Lemaire, 2009). While the Brown Nightjar is known to be in this area, the territories of the Brown Nightjar and the mysterious nightjar did not seem to overlap (Butchart, 2007). The Dowsetts concluded that a little studied forest nightjar is hard to catch because they never perch on tracks and they like to sing high in trees (Dowsett-Lemaire and Dowsett, 2000).

More Encounters in Lobéké (December 1997, January 1998)

After the Dowsetts left, three more encounters with mysterious nightjars occurred in Lobéké National Park. One happened on December 26, 1997 when one sang at Kupandaka at dusk in a swampy forest at the edge of Kupandaka Swamp. Two other encounters happened in a dryland forest on the edge of Mala Swamp in Nki on January 4 and January 6, 1998 respectively. These environments at these areas of the park had either evergreen or semi-evergreen forests with some closed canopy forest. The birds sung at an altitude of 350-550 m and did not respond to playback (Dowsett-Lemaire, 2009).

For a distribution map based on these encounters, click here.

Since 1998, no further recordings or encounters have been reported of this species.

The Itombwe Massif in the African Great Lakes region is one of the most densely populated and underdeveloped regions in Africa. Habitat loss and cattle grazing have intensified with every passing year in the Itombwe Mountains as poverty, natural disasters (especially a maize blight that hit the region in the 1990s), and political violence have pushed farmers in the region to cut down more forest for agriculture and pastoral activities. Many of Itombwe's endemic bird species cannot tolerate modified environments (Omari et al., 1999).

The Itombwe Nightjar is thought to have a restricted range limited to transitional forests (tropical or subtropical), moist lowlands, and moist montane environments (particularly in transitional forests where the only specimen was found at 1,280 m). Due to lack of data, it is possible that members of this species could be found at lower or higher altitudes in montane and lowland forests between 350-1,860 m (IUCN Red List).

Most of Itombwe's forests remain intact despite the fact that half of the region's habitats were already modified or degraded by the late 1990s. The highest degree of undisturbed habitat lies at the center of the region. There was discussion among many conservationists and government officials about setting up a park in Itombwe. However, this never came to fruition because there was a lot of resistance among the local population who feared they would be ejected from their homes if a park was established. Market hunting and poaching is an enormous challenge for the region's wildlife which have seen their populations decimated by poachers and hunters (Omari et al., 1999). In 2014, there was evidence of poachers, hunters, and bird catchers using mist-nets to catch birds. The disappearance of large mammals in these forests compelled them to find other wildlife to capture and hunt. Ten years later it is unclear how the endemic bird populations of the Itombwe forests have been affected by these trends. One can only assume that the poaching and hunting have only intensified with the rise in climate change, poverty, and violence in the region (Monga Bay News).

The greatest challenge is figuring out who exactly is the Itombwe Nightjar? There is so little known about this bird. There have been no confirmed sightings and the only evidence we have are mysterious recordings from researchers from the field who believe it to be the nightjar. Nonetheless, these recordings and encounters are all we have. Further research needs to be done on these recordings and how the Itombwe Nightjar is similar to other nightjar species in the region.

According to the Dowsetts and others, assuming that the mysterious nightjar from the recordings is the Itombwe Nightjar, contend that the species' song is similar to that of the Swamp Nightjar. Both species give off five notes or more per second but the structure for each song is different. The sounds are also distinct. The Swamp Nightjar's tjok-tjok-tjok has a glissandi with a sharp drop in frequency. The notes of the Itombwe Nightjar are square with a slight drop in frequency. The timbre of the Itombwe Nightjar is harder and has a lower pitch. The calls of the Itombwe Nightjar are harsh and rolled whereas those of the Swamp Nightjar have a melodious tremolo.

In terms of habitat, the Itombwe Nightjar and the Swamp Nightjar prefer different habitats. The Swamp Nightjar is known to avoid forests. Françoise Dowsett-Lemaire says this can be clue to help with identification, “Anyone hearing a song resembling that of Swamp Nightjar but coming from dense forest should be on the alert” (Dowsett-Lemaire, 2009). According to observations, the Itombwe Nightjar is a nightjar with a churring song that prefers a forest environment. To be more specific, this species seems to prefer a semi-evergreen forest with a broken canopy that match the habitats seen on the hills and massifs in Itombwe. This type of habitat is not only seen in Itombwe but also on the Congolese-Cameroon border, the northern edge of the Guineo-Congolan region, in the southern regions of the Central African Republic, and in the northern Congo-Kinshasa region (all of which contain areas that are poorly documented to this day). The Itombwe Nightjar could potentially be present in any of these environments within this range.

The range of the Itombwe Nightjar needs to be considered as being wider than just the Itombwe Mountains. Apparently, the species also has a wider altitude range. The recording made by Thomas Butynski was taped at 1,860 m in an open-canopy forest on a hillside 4 km from the nearest grassland in Itombwe. The only type specimen was found at 1,280 m. The recordings made by Dowsett-Lemaire and Butynski are identical even though they were made in different areas and altitudes.

From what we know about the Itombwe Nightjar's physical characteristics, the species is similar in size to the Brown Nightjar. The Itombwe Nightjar's stocky appearance is due to the species' short tail which is the shortest of any nightjar in Africa. This stocky appearance matches the few glimpses of the mysterious bird researchers were able to see (Dowsett-Lemaire, 2009).

Despite a sharp rise in the amount of violence due to a rebellion erupting in South Kivu, Democratic Republic of the Congo, local ornithologists continue the search for the Itombwe Nightjar. One of them includes Papy Dunia who travelled to Itombwe in April 2024. He set up several autonomous recording units (ARUs) in the area which he'll retrieve later in the year. Mist-netting in the area later in the year is also a possibility. If the ARUs pick up sounds similar to the recordings made by Butynski and the Dowsetts of the mysterious forest nightjar in the late 1990s, then it is possible that the same species might still be in the area (Monga Bay News).

Order: Caprimulgiformes

Family: Caprimulgidae

Genus: Caprimulgus

Species: Caprimulgus prigoginei