Male and female South Is saddlebacks (Philesturnus carunculatus carunculatus) have monomorphic plumage characteristics and are not easily distinguishable. In this study, we developed discriminant functions to classify males and females using birds of known sex from Ulva I. Three discriminant functions using tarsus length, body mass, and a combination of tarsus length and body mass could classify birds with 90% accuracy.
Three endemic forest bird species, masked shining parrot Prosopeia personata, giant forest honeyeater Gymnomyza viridis, and golden dove Chrysoenas luteovirens were surveyed using distance sampling from forest tracks at 4 sites on Viti Levu, Fiji. Repeat surveys were made at 1 site to better understand the factors affecting detectability. Seasonal changes in detectability reflected the number of calling birds and were almost certainly linked to breeding. The highest mean densities (41 masked shining parrot km-2 (birds), 33 giant forest honeyeater km-2 (calling birds) and 14 golden dove km-2 (calling males) were found in low- to mid-altitude old-growth forest. Densities in degraded re-growth forest and mahogany plantations were about 30% and 50% lower, respectively. Densities in upland forest were very low for masked shining parrot (2.5 km-2), but moderate for giant forest honeyeater (21 km-2)and golden dove (8 km-2). Provisional population estimates of 50,000 pairs of masked shining parrot, 70,000 pairs of GFH and 60,000 pairs of golden dove were made though attention is drawn to the limitations and uncertainties of these estimates. In common with many Pacific Islands, the endemic avifauna of Fiji is threatened by forest loss and degradation and a lack of protected areas. This study could assist in the design of effective protective areas as well as being a baseline for future surveys.
Platform terminal transmitters (PTTs) using the CLS:Argos System were attached to adult sooty shearwaters (Puffinus griseus) at Taiaroa Head, South I, New Zealand. Three PTTs were attached to adults during the pre-breeding period, and 2 were attached to adults during the incubation period. During the pre-laying excursion, 1 male flew a minimum distance of 7700 km over 34 days while another male flew 4200 km during 28 days. The minimum distance flown by a female was 3700 km during 16 days. Pre-breeding birds mainly frequented waters <1000 m deep. During the mid-breeding period a male sooty shearwater flew a minimum of 18000 km in 36 days, while the female flew 4100 km in 13 days. There were comparatively fewer flight locations close to the Otago and the Canterbury coasts for mid-breeding deployments compared to pre-breeding deployments, and most were in waters >1000 m deep.
The 2 species of royal albatrosses, the southern (Diomedea epomophora) and northern (D. sanfordi), breed only in New Zealand, but adults and juveniles are common off the western coast of South America. They can be separated on their plumage at sea. This paper examines the variation in plumages of the royal albatrosses seen in southern Chilean shelf waters at 46°30´S, based on a series of photographs taken in Sep 2004. D. sanfordi were identified by the uniformly black dorsal surface to their wings, and by the absence of a white leading edge to the wing in flight. In contrast, most individuals of D. epomophora had a white leading edge to the humeral and radial section of the wing and generally white flecking on the upper surface of the wing. However, some individuals identified as D. epomophora had no white on the leading edge nor any white on the dorsal surface of the wing. The black carpal patch near the leading edge of the ventral wing surface was variable in occurrence and was not considered diagnostic. D. epomophora out-numbered D. sanfordi by c.9 to 1 in southern Chilean coastal seas in Sep 2004. Most D. sanfordi may have left the area by Sep, moving either to the Patagonian shelf, or to Australasian seas.
The survival of adult and fledgling Antarctic terns (Sterna vittata bethunei) at the subantarctic Snares Islands was studied from 1976 to 2007. Annual adult survival was 0.91 and that of birds banded as fledglings was 0.42 in the first year and 0.94 in subsequent years. On average, a breeding adult would have a reproductive life-span of 10.2 years while a fledgling that survived the first year would have a life expectancy of 17.4 years. The disparity between the survival of birds banded as breeding adults and fledglings is probably be due to relatively small samples sizes. The estimated survival rates of Antarctic terns are similar to those reported for New Zealand fairy terns (S. nereis davisae). No terrestrial predators occur at the Snares Islands, and extensive predator-control is undertaken in the areas where New Zealand fairy terns nest, and so these survival rates may be typical of other breeding terns in the absence of terrestrial predators.
We counted the black shags (Phalacrocorax carbo) frequenting a night roost at Melling, 4.5 km up-river from the Hutt River mouth, Wellington, New Zealand, and studied the timing of breeding at various colonies in the Wellington region. Numbers at the roost were counted from Oct 1993 to Sep 1998: maximum and minimum mean monthly counts were in Feb and Aug, respectively. The main egg-laying period of 3 coastal colonies (0–2 km) (Mar–May) was c. 3 months earlier than at 2 inland (5 – 33 km) colonies (Jun–Aug. We discuss the possibility that the difference in timing of breeding by shags in colonies at different distances from the coast is related to the different timing of peak prey availability in the 2 habitats (coastal marine, and inland riverine).
From satellite tracking data, we recognised 5 major flight patterns in the annual cycles of 3 Chatham albatrosses (Thalassarche eremita) tracked in 1997 and 1998: foraging flights while the birds were breeding; eastward and westward migrations across the southern Pacific Ocean; northward migration along the South American coast; and localised foraging at low latitudes off the northwest coast of South America. We hypothesised that the 5 modes of flight indicated different biological activity. The associated speeds, point-to-point distances flown day-1, and other indices of activity were inferred from distances and times between satellite location records. Mean minimum point-to-point flight speeds were up to 85 km h-1 and were a function of the time interval for the measurement. Daily rates of change for latitude and longitude and the minimum daily distances travelled were calculated. These are the 1st measurements for this species of the sustained speed of flight point-to-point over varied time periods, and for short and long distances throughout the year. These data and the analytical techniques developed show what information can be obtained from a few individuals, and the confounding variables that result from the satellites’ orbits, and the transmitting characteristics of long-duration PTT experiments. The interrupted reception of transmitters through the intermittent satellite passes biases speed and other measurements and difficulties interpreting these data are discussed. The results provide a guide to the design of satellite transmitter experiments for long distance and duration studies with other oceanic species. They also contribute to an understanding of where this species obtains its food, and of its potential risk of interaction with fisheries.