Hydrornis schwaneri (Bonaparte, 1850)

Gulson-Castillo, Eric R., Pegan, Teresa M., Greig, Emma I., Hite, Justin M., Hruska, Jack P., Kapoor, Julian A., Orzechowski, Sophia C., Shipley, J. Ryan & Winkler, David W., 2019, Notes on nesting, territoriality and behaviour of broadbills (Eurylaimidae, Calyptomenidae) and pitas (Pitidae) in Tawau Hills Park, Sabah, Malaysian Borneo, Bulletin of the British Ornithologists’ Club 139 (1), pp. 8-27 : 22-23

BORNEAN BANDED PITTA Hydrornis schwaneri

Common on steep slopes and ridges leading to Gunung Lucia. Between the hostel and the summit, we observed at least four pairs along the trail at c. 950 m on 12 July 2012. On 22 July 2012, we found at least one individual in the lowlands near the park headquarters at c. 300 m. It was observed five more times in this area on 24–30 July 2012 (when our visit ended), and was generally easy to find, calling frequently. The bird stayed in a relatively small area ( Fig. 11 , yellow points). Because this area was within our main study area and well-surveyed throughout the period, we are confident that it was not present and calling before late July.

Although Lambert & Woodcock (1996) observed that Bornean Banded and Blue-headed Pittas Hydrornis baudii are never found in the same area of forest at Danum Valley, at Tawau Hills that which the H. schwaneri occupied in 2012 overlapped with a Blue-headed Pitta territory ( Fig. 11 ). In fact, the former was first observed within the lowland study area on 24 July 2012 in precisely the same location as a pair Blue-headed Pittas had been present c.1 hour prior. On 30 July, JMH spent several hours observing a female Blue-headed Pitta with a juvenile (see below). Once the female hopped out of view behind a tangle and JMH heard and saw a ‘scuffle’, with branches in the tangle moving. After this, a Bornean Banded Pitta emerged from the same area the female had disappeared, suggesting that an interaction between the two species had occurred (although contact between them could not be confirmed). Lambert & Woodcock (1996) suggest that habitat preferences are responsible for the apparent segregation of Bornean Banded and Blue-headed Pittas in Danum, but the potential interspecific interaction we observed suggests that competition could play a role as well.

Bornean Banded Pittas were present on the slopes of Gunung Lucia again in 2013, but none was observed in the lowlands near the park headquarters. It is possible that their occurrence in this area is seasonal, or that the sightings in 2012 in the lowlands were unusual—perhaps a dispersing individual that eventually moved elsewhere permanently.

Figures

Figure 11. Map of the topography of our study area showing sightings of four species of pittas during the 2012 field work: Black-crowned Pitta Erythropitta ussheri (purple), Blue-headed Pitta Hydrornis baudii (blue), Bornean Banded Pitta H. schwaneri (yellow) and Blue-banded Pitta Erythropitta arquata (red). Each point represents a sighting. Variation in point size and shape is an artefact of 3D plotting. The map demonstrates that the areas occupied by each species overlapped considerably, especially on the ridge in the centre, where all four species occurred in close proximity. Black-crowned Pitta was seen more commonly in low swampy areas, whereas the other three species occurred mainly on this ridge and its slopes. A fifth species, Hooded Pitta Pitta sordida, was heard infrequently and seen just once, a juvenile, at the green point. Grey lines represent trails, the brown line a water pipeline, and the blue line the Tawau River. 3D map courtesy of JAXA (2015).