Solomons Nightjar Eurostopodus nigripennis, listed as Vulnerable by BirdLife International, has previously been recorded only from the north and central Solomon Islands. Even within the species' known range there are few records, limiting knowledge of its ecology. We provide photographic evidence of a Solomons Nightjar nest in a streambed on the island of Malaita at an altitude of c.270 m—the first record on this large island. This observation, combined with traditional local knowledge, suggests that the species may have a wider range of nesting habitat than previously documented, and that further surveys in collaboration with local tribespeople could be important for conservation efforts.
Nightjars are generally crepuscular or nocturnal, and this, combined with their cryptic plumage, results in many gaps in our knowledge of the family as a whole (Holyoak 2001, Hadden 2004). One of the least-known species is Solomons Nightjar Eurostopodus nigripennis (Cleere 2010, Dutson 2011). Here, we report the first record of the species for the island of Malaita, in the Solomon Islands, précis the available literature, and summarise what is known by local tribespeople.
On the afternoon of 5 September 2018, while searching for study sites for a collaborative bird survey of East Kwaio, Malaita (Callaghan et al. 2019), MA found an unidentified egg (Fig. 1a.) on the ground at 08°59′43.7994″S, 160°58′58.0794″E. MA installed a camera trap in the vicinity (Fig. 1b). When the footage was reviewed, it was discovered that the egg belonged to Solomons Nightjar (Fig. 1c), known as baababa in the local Kwaio language. The adult, photographed on 6 September 2018, was identified by the lack of white markings on the wing and tail, and a pale collar extending to the nape (Fig. 1c–e). According to Dutson (2011), the only other potential caprimulgid in this region (based on nearest known range) is Large-tailed Nightjar Caprimulgus macrurus, which has white patches in the tail. Whitethroated Nightjar Eurostopodus mystacalis was also excluded based on wing pattern (Dutson 2011). Local tribal people stated there was only one type (species) of baababa in the vicinity. The habitat consisted of a streambed, c.270 m above sea level (Fig. 1f), surrounded by secondary forest. The bird abandoned the nest, and the egg remained in situ one week post-abandonment before disappearing. A nightjar was subsequently seen in December 2018 and January 2019 in the vicinity. Local tribal leaders stated that the baababa is not found any higher in the valley than the September 2018 sighting, and is only occasionally seen along the riverbed and in adjacent abandoned gardens.
This represents the first documentation of the species for the island of Malaita, and one of only a handful of records throughout its global distribution (Hadden 2004). Even within its previously documented range (north and central Solomon Islands; Cleere 2010), its status is poorly known. Solomons Nightjar is classified as Vulnerable by the IUCN, based on its ‘very small, declining population, within which all subpopulations are likely to be very small' (BirdLife International 2019). Local people in the vicinity described the baababa as very rare, wary of people, well camouflaged by day and only seen at night. Consistent with this, there are currently only four records in the global database eBird (https://ebird. org/species/solnig1). Read (2013) also noted a paucity of records of Solomons Nightjar in the literature, with an apparent hotspot on Tetepare Island which has a long-standing conservation programme. That just one egg is laid matches both traditional and scientific knowledge of this species’ behaviour (Cleere 2010). Solomons Nightjar is most commonly found nesting on beaches (Mayr 1945, Coates 1985, Read 2013), but this individual was nesting in a dry streambed, following the seasonal floods. The streambeds are relatively clear areas on sandy / pebble islands within rivers or on the banks of rivers. These small islands are usually vegetated with small shrubs. Local people stated that baababa do not venture into gardens with regular human activity or into rainforest. This record suggests that Solomons Nightjar may have a wider range of nesting habitats than previously documented, and that at least on Malaita, the birds adapt their egg-laying schedule based on the wet and dry seasons.
Figure 1.
Solomons Nightjar Eurostopodus nigripennis, East Kwaio, Malaita, September 2018, showing (a) egg when initially discovered (Maasafi Alabai), (b) egg on camera trap, (c) adult standing over egg, (d) adult showing white throat and lack of white in tail, (e) adult showing pale collar extending to nape, and (f) riverbed where the nest was located (Maasafi Alabai)
![img-z2-1_325.jpg](ContentImages/Journals/bbrc/139/4/bboc.v139i4.2019.a4/graphic/WebImages/img-z2-1_325.jpg)
The species is of conservation concern, largely due to the lack of data (BirdLife International 2019). Potentially, this is at least in part because its vocalisations are very poorly known—with two descriptions (Gregory 2017) and no recordings—leading to a potential reduction in records (Mayr 1945). Even local people are unfamiliar with the calls / songs of the species, however they have heard baababa chicks uttering a hiss. Interestingly, baababa is a ‘tabu’ bird in Kwaio culture, so this species is not hunted and its eggs cannot be eaten, meaning that less about its behaviour is known than for other species. Furthermore, the word baababa describes the characteristic of the bird that crouches over to ‘hide'. Indeed, the Kwaio word for hide is ‘baba'. Because of this, this bird is poorly known and only observed when it lays eggs and in the immediate environs of its nest.
In addition to the first record and nesting of Solomons Nightjar on Malaita to be reported in the scientific literature, we also highlight the low detection probability of this species throughout most of its potential range on Malaita because of its elusive behaviour, and the relative lack of scientific visits to the island in search of birds (Callaghan et al. 2019). We recommend dedicated surveys for Solomons Nightjar in collaboration with local tribal groups, which could ultimately better elucidate the species' conservation status on Malaita and throughout the Solomons Islands.
Acknowledgements
We thank Nigel Cleere, Guy Dutson and Walter Boles for comments that improved the manuscript. For their hospitality and hard work in the field we are indebted to Bukele, Taawa'i, Dorothy, Etalamo, Faaisia, Fifanabe'u, Fotageni, Fou'asua, Jimsan, John, Kotoringi, Laete'esafi, Laminae'a, Lengari'i, Loni, Lo'ubata, Mageni, Naata, Nabe, Rubeamae, Sale, Susufia, Tagwa, Telegeni and Wedi. Funding for our field work was provided by the Australian Museum Foundation, to whom we are extremely grateful.