A Congolese endemic; Prigogine's Greenbul, a brief encounter.

by Tommy Pedersen

This article was written for ABC - African Bird Club in August 1997. 

In 1993 - 1994 there were three birders living in Goma, eastern Congo (formerly Zaire); Marc Languy, Laurent Esselen and myself. Situated in the centre of the Albertine Rift, we enjoyed some excellent birding.

On site; Marc Languy and me, with our driver and guard.

During 1993 we planned a trip to the Lendu Plateau, west of Lake Albert (ex Lake Mobutu), which should be undertaken in February 1994.

We were especially interested in three species, Chapin's Crombec Sylvietta [ leucophrys] chapini, Prigogine's Greenbul Chlorocichla prigoginei and Chapin’s Flycatcher Muscicapa lendu.

The Prigogine’s Greenbul is classified by IUCN as "vulnerable".

Prigogine's Greenbul  (Chlorocichla prigoginei).

Chapin's Crombec might be a form of White-browed Crombec Sylvietta leucophrys(Dowsett and Dowsett-Lemaire (1993, p. 358), who note that "Further field investigation is needed before accepting that this form is undoubtedly a good species").

Chapin's Crombec is only known from the Lendu Plateau, whereas the Prigogine's Greenbul is mainly known from the Beni - Butembo area north-west of Lake Edward (ex Lake Idi Amin) and two observations from the Lendu Plateau.

Especially interesting is the fact that the Prigogine's Greenbul has never been observed by ornithologists in the field, but only described from museum-skins.

The Lendu Plateau is an isolated plateau situated west of Lake Albert, in the north-eastern Congo, surrounded by lowland savannah to the north, west and south, and Lake Albert to the east.

On this dry and deforested plateau there are a few isolated forest-patches of slightly degraded montane forest, under serious threat from the surrounding villages. Birdlife in these forest-patches is very rich.

When overflying the Lendu Plateau in 1993, we could see two main forest-areas. One (the Djugu Forest) was close to the village of Nioka, and the other one was close to the plateau-edge, east of Nioka, and difficult to access by car. The size was difficult to estimate, but each could be something like 10 soccer-fields in total area. The Djugu Forest is situated at appx. 1.700 meters above sea level.

I do not know the actual forest-cover in earlier days, but it is likely that it was considerably bigger than today.

Logging by local villagers were seen everywhere.

The only other ornithologist we know of that has been here was Mr. J.M.VRIJDAGH, in 1941 - 42. He recorded the Joyful Greenbul only twice, and since the Prigogine's Greenbul was not yet discovered, it is impossible to know with certainty which of the two species he really observed.

We arrived the Lendu Plateau on February 06 1994, and could stay only two days. We birded the Djugu Forest near Nioka on February 07 from 12:00 - 16:00 hours and February 08 from 09:00 - 14:00.

The first Prigogine's Greenbul was discovered by Marc Languy within the first hour of entering the Djugu Forest. It was alone in the understorey of fairly damp forest. No sound was ever heard from the this bird, nor from any of the later individuals. It stayed still for a minute, then it flew away into more dense forest.

Another bird was later found nearby, accompanying a group of 12 very active and noisy Joyful Greenbuls

C. laetissima. It stayed with the flock until they disappeared from sight, two minutes later. They were seen along a forest path (driveable), and stayed 1-3 meters above ground. They were never deep inside the foliage, but very visible. The Joyful Greenbuls were very active, calling a lot and often flicking the wings. This was never observed from the Prigogine’s Greenbul, and no call was heard. It had no difficulty in staying with the active group. It sat often on large leaves of an un-identified bush.

The following day another Prigogine’s Greenbul was spotted near a small stream, following a group of very vocal Joyful Greenbuls. Behaviour as on the previous day.

The Prigogine's Greenbul is separated from the Joyful Greenbul on its clear grey area between the bill and eye, and a distinct pale grey eye-ring. These characters were easy to see in the field, both with binoculars and with Kowa telescopes (25 X magnification)

No Chapin’s Flycatchers were seen during our brief visit.

After searching for the Chapin's Crombec for two days in the forest and around Nioka, none were found.

Mr. J.M.VRIJDAGH did observe several individuals around the Nioka hotel (now abandoned) in July - November 1941/42, and once at Djugu in November 1941.

The Lendu Plateau is very rich in birds, and we saw many interesting species; Black Bee-Eaters were common, Grauer's- and Purple-throated Cuckooshrikes seen several times, Mangbettu Sawwing Psalidoprocne [ pristoptera] mangbettorum were common and the endemic Bedford's Paradise-Flycatcher seen once.

It is clear that this area will benefit from future visits, and I will be happy to supply any information needed.