Search

The diets of the Little Eagle Hieraaetus morphnoides and Wedge-tailed Eagle Aquila audax breeding sympatrically in the Australian Capital Territory during 2011–2019 were compared by analysis of pellets and prey remains (six Little Eagle territories and 13 Wedge-tailed Eagle territories; 69 and 49 collections for a total of 232 and 256 prey items, respectively). Little Eagles took 33% mammals (29% European Rabbits Oryctolagus cuniculus), 44% birds, 6% reptiles and 17% insects by number, and 65% mammals (62% Rabbits), 27% birds, 8% reptiles and

The diet of the Australian Hobby Falco longipennis was studied in Canberra (ACT), in the summers of 2002–2003 to 2004–2005 and 2005–2006 to 2008–2009 by analysis of prey remains and pellets (28 and 40 collections for a total of 229 and 132 prey items from six and four nests, respectively). The Hobbies’ breeding diet in the first period consisted of 73% birds, 1% microbats and 26% insects by number, and 98% birds

All animals face the decision of where to breed, a decision that exerts a strong impact on fitness. We examined changes in choice of nest site in peregrine falcons (Falco peregrinus) over a 17-year period in northern Spain. Falcons had a mean of 3.1 eyries per territory, each location used for a mean of 3.0 consecutive years. Surprisingly, change in eyrie location was not predicted by breeding productivity. However, breeding success decreased with the number of consecutive years that eyries were reused. Ectoparasitic infestation was not a significant predictor in the models. The number of fledglings in the previous season was the main factor explaining the eyrie-switching decision, with successful pairs being more prone to move. Newly established females showed a higher tendency to switch (59%) than older territorial females (38%) but males did not exhibit the same tendency. High rainfall in April had a negative effect on productivity. In the case of females, changing the eyrie from one season to the next had a positive effect on productivity. In the case of models run with males as a random factor, rainfall in April and eyrie shelter reached significance. So, contrary to the ‘win–stay, lose–switch’ rule and in direct contrast with general literature, peregrines changed eyries after successfully raising large broods and eyrie switching increased the breeding success of females but not of males.

Over a 30-night period a Common Myna Acridotheres tristis was observed attacking Common Brushtail Possums Trichosurus vulpecula and harassing a female Southern Boobook Ninox boobook near her nest. One night a Myna that had been attacking Possums was chased by the male Boobook, which appeared to be chasing it as prey. We did not observe further attacks by Mynas after this night. Common Mynas were found in the dietary analysis for this pair of Boobooks.

Brown Falcons (Falco berigora) are generalist predators that take prey from a range of different taxonomic groups. Further, this species is one of the most widespread raptors in Australasia, providing great scope for dietary flexibility. However, few studies have reported on the diet of this species, and none in any detail for the relatively dry, continental climate of the Canberra region of southeastern Australia. We therefore examined this species' diet from 29 collections of prey remains and pellets from 20 nesting territories over five breeding seasons of Brown Falcon pairs breeding within 40 km of Canberra in 2002–06 and again in 2009. A total of 307 prey items was recorded, 15 of which were novel for this species. These novel prey items largely reflected locally common species that were of a similar size and niche to prey previously recorded in other regions, such as a new prey species of quail or beetle. Unusual prey included garden snails (Helix aspersa) and an owl, the Southern Boobook (Ninox novaeseelandiae). Other infrequently captured prey items such as freshwater molluscs (Corbicula australis and Glyptophysa gibbosa) and crayfish (Cherax sp.) illustrated the extraordinary dietary flexibility of Brown Falcons. In comparison with previous detailed studies, Canberra-based pairs had a relatively small geometric mean prey weight of 7.7 g, and tended to take a higher proportion of invertebrates across a relatively narrow niche breadth. When biomass was considered, rabbits (Oryctolagus cuniculus) were an important food source, making up half of the total biomass in the diet.

Adjacent nesting home ranges of four radio-tagged Southern Boobooks (Ninox novaeseelandiae) were studied in a Canberra, Australia, woodland over 418 observation nights during four breeding seasons. Spatial locations and bouts of territorial calling (“boobook calls”) were recorded during each observation night. Home ranges and core areas were computed from the spatial locations using minimum convex polygons and characteristic hull polygons. Home-range sizes varied by individual owl, between breeding seasons, and by estimation method, ranging from 18.1 to 205.8 ha. Core-area estimates varied from 0.2 ha to 19.6 ha, indicating intensive use of core areas within much larger home ranges. Overall, about 26% of the boobooks' vocalizations occurred within core areas and about 56% within the home range but outside the core area, often near the border shared with the adjacent pair. Approximately 21% of boobook calls were observed on or outside home-range boundaries, which suggested that owls actively defen...

Recent concern about the decline of the Little Eagle (Hieraaetus morphnoides) in southeastern Australia has raised questions about whether Wedge-tailed Eagles (Aquila audax) might be implicated in this decline. The ecology, including the diet, of Little Eagles is rather poorly known. The diet of the Wedge- tailed Eagle is better documented, but the overlap in prey used by the two eagles has been little studied. Near Canberra between July 2002 and January 2008, we identified 1421 and 192 prey items from nests of Wedge-tailed Eagles and Little Eagles, respectively. Wedge-tailed Eagles' diet was similar to that reported elsewhere. In addition to European rabbits (Oryctolagus cuniculus), Little Eagles specialized on birds, but tended to avoid macropods, a main prey of Wedge-tailed Eagles, and there was little overlap in prey used by the two eagle species. Although Standardised Food Niche Breadth and Shannon Diversity Index were similar for the two eagles, Wedge-tailed Eagles captured significantly larger prey, as indicated by the difference in Geometric Mean Prey Weight, 1298 g for Wedge-tailed Eagles and 249 g for Little Eagles, which reflected the fivefold difference in mass between male Little Eagles and male Wedge-tailed Eagles. We suggest that direct competition for prey probably was not the cause of the Little Eagle decline.

We collected prey remains and pellets at 16 Peregrine Falcon (Falco peregrinus) nest territories (975 prey items from 152 collections) and one Australian Hobby (F. longipennis) territory (181 prey items from 39 collections) during four breeding seasons in two time periods: 1991–1992 and 2002–2003, a total of 60 peregrine nest-years and three hobby nest-years. By number, European Starlings (Sturnus vulgaris) were the main prey taken by both falcons in 1991–1992 and 2002–2003, but starlings made up a smaller percentage of the diet by number in the latter period, apparently because their numbers had declined in the wild. Although the geometric mean of prey weights and geometric mean species weights were similar in the two time periods, both falcons compensated for the decline in European Starlings in the latter period by taking a greater variety of bird species, particularly small numbers of mostly native birds, rather than taking more of one or two other major prey species. Peregrines took 37 bird ...

The diet of the White-bellied Sea-Eagle (Haliaeetus leucogaster) in Australia is poorly known, especially inland. The diet of the Wedge-tailed Eagle (Aquila audax) is better known, but the overlap in prey used by the two eagles has not been studied. In four inland territories of White-bellied Sea-Eagles, and five territories of Wedge-tailed Eagles nesting close to them (range 1.6–5.1 km apart) between July 2002 and December 2004, we identified 116 and 118 prey items from nests of White-bellied Sea-Eagles and Wedge-tailed Eagles respectively. There was little overlap between the diets, and that of Wedge-tailed Eagles was similar to that reported elsewhere. In addition to fish, White-bellied Sea-Eagles specialised in aquatic birds, such as cormorants, grebes or ducks, and aquatic reptiles, such as turtles or water dragons, but tended to avoid terrestrial birds and reptiles, such as ravens and skinks, or mammals such as European Rabbits (Oryctolagus cuniculus) and macropods that were the main prey of nearby Wedge-tailed Eagles. Though food niche breadth was almost identical for the two eagles, Wedge-tailed Eagles captured significantly larger prey, as indicated by the geometric mean prey weight. Our results indicate that closely located breeding pairs of riparian Wedge-tailed Eagles and White-bellied Sea-Eagles were not competing for food, owing to the differences in foraging preferences, at least during the breeding season. We found no evidence to support the claim that the spread of rabbits assisted the increase of breeding numbers of White-bellied Sea-Eagles.

Brood sizes of Peregrine Falcons in south-eastern Australia were manipulated to examine the effects on parental foraging effort and offspring growth rate. In broods enlarged by one, nestling growth rates were not affected but parents responded by bringing larger prey species and more biomass than did parents of control or reduced broods. Prey size and biomass decreased for the reduced brood. We conclude that parents appeared to increase hunting efforts to meet greater demands for food, and decrease hunting efforts for the reduced brood, but that direct observation of hunting behaviour by colour-marked and radio-tagged Peregrine Falcons with enlarged, reduced, and natural broods is necessary to determine how parents respond.

Since the late 1980s ornithologists have reported an unknown Otus owl from the island of Sumba, Indonesia. From a specimen of this unknown owl we analysed the mitochondrial cytochrome b gene in feathers and compared its sequence with those in our data library, which includes most owl genera. A phylogenetic analysis unequivocally places the unknown owl into the Ninox clade. It differs from N. novaeseelandiae and N. scutulata by 8.2 and 9.1% nucleotide substitutions, but our Ninox data set contains few representatives so we cannot define to which other Ninox species it is most closely related. There was no overlap in measurements of body length or mass for this specimen and those of other Ninox known from this region. The call of this new owl was a monosyllabic hoot repeated about every three seconds and quite unlike the repeated 'cluck-cluck-cluck' made by the endemic N. rudolfi or the disyllabic notes made by most Ninox, including others in the region. For this new species we assign the common name Little Sumba Hawk-Owl. The conservation status of this owl has yet to be determined, but the species might be threatened and we propose it as Data Deficient.

The taxonomic status of the geographically isolated population of Short-toed Snake-eagle Circaetus gallicus on the Lesser Sundas (=Nusa Tenggara) has been controversial. In the past they have been regarded as either a migrant population or a recently arrived resident population. Here we obtained DNA sequences from the mitochondrial cytochrome-b gene and combined genetic data with assessments of published and novel morphological data to clarify the taxonomic status of the Lesser Sundas population of C. gallicus. The cytochrome-b distance between the Lesser Sundas and Palearctic populations of C. gallicus is consistent with subspecific differentiation, indicating a possible divergence during one of the most recent Pleistocene glaciations. Although some of the morphological distinctions show overlap, the new subspecies can generally be diagnosed from nominate C. gallicus gallicus by being smaller and paler, and exhibiting less spotting and barring. Unlike nominate populations from mainland Eurasia, the new subspecies seems to lack pronounced sexual dimorphism. We here describe this new subspecies to science and discuss its biology and conservation status.

There has been little research investigating how symptoms of schizophrenia and changes in symptomatology across the course of the illness relate to measures of quality of life in patients. We examined this issue in 45 patients assessed at hospital admission for illness exacerbation, at stabilization (prior to discharge) and at follow-up (5-9 months post-discharge). Symptom ratings at each time period consisted of the Brief Psychiatric Rating Scale (BPRS) and the Negative Symptom Assessment (NSA). The Heinrichs-Carpenter Quality of Life Scale (QLS) was administered upon admission to the hospital (assessing the 3 months prior to admission) and again at follow-up. Correlational analyses revealed relationships of both positive and negative symptoms with quality of life. These relationships are particularly strong at stabilization. Stepwise regression analyses revealed changes in the NSA motivation component to be most important in predicting quality of life for the patients at follow-up. BPRS psychosis and paranoia components are important predictors of quality of life at stabilization (but not during acute exacerbation). These results are important in terms of understanding the impact of changes in symptomatology on the quality of life for patients with schizophrenia as well as in targeting specific symptom clusters for treatment to maximize quality of life post-hospitalization.

Since the introduction of phenothiazines in the 1950s, clinicians have used anti-psychotics in combination. This practice has previously been declared irrational as traditional antipsychotics were thought to work by similar mechanisms. However, the advent of the atypical antipsychotics provides a cadre of new medications with varying pharmacodynamic profiles. Once again, the potential use of combination antipsychotic therapy is being explored.

Recent data and clinical experience confirm that, in spite of superior efficacy for treatment-refractory schizophrenia, a substantial proportion of patients receiving clozapine will continue to experience disabling symptoms. Optimizing clozapine monotherapy is the first step in the management of "clozapine nonresponders." Described here is a synthesis of the available literature on the range and efficacy of clozapine augmentation strategies that may be used when monotherapy fails. Treatment options include adjunctive antipsychotic medications, mood stabilizers, selective serotonin reuptake inhibitors, glycinergic agents, and electroconvulsive therapy. The evidence favoring one augmentation strategy over another is lacking; overall, adjunctive therapy is associated with only modest clinical improvement. Moreover, case series and open-labeled clinical trials dominate the extant literature, and there is a dearth of double-blind trials comparing these augmentation agents. Current systematic efforts to enhance the treatment of these patients with adjunctive therapies are worthy of being studied in carefully conducted clinical trials.

The world's owls have become focal species in the conservation movement because some, like the Powerful Owl (Ninox strenua) and Spotted Owl (Strix occidentalis), are tied to old growth forests and have been adversely affected by the new generation of rodenticides which are more toxic and persistent than old ones and have the potential to cause secondary poisoning to rodent predators. Owls in Australia are difficult to find and study, so comparitively little is known about their biology. Even less is known about the statues, taxonomy, and biology of those species and sub-species living in tropical and subtropical environments and on islands. Many island species and sub-species are at risk, and some have already been lost. The chapters in this book derive from papers at a five-day conference devoted to the study of owls, which was held at the Australian National University, Canberra, in January 2000. The conference was the third in a series of international meetings on owls. It provided an opportunity for the presentation of new findings, for northern and southern hemisphere owl researchers to meet and discuss issues of mutual concern, and also for northern biologists to see some of the markedly distinctive species of the region.

The density of pairs of Peregrine Falcons occupying nest sites near Canberra was high (minimum of one pair per 343 sq. km). Nest sites were scarce. Falcon pairs were spaced no closer than 2 km apart and were clumped where there were suitable cliffs; within these clumps the spacing of cliffs used for nesting was fairly regular while that of all cliffs was random. Over 12 years, occupancy of nest sites was high and stable with between 82 and 100% of sites occupied annually by at least one Falcon. Variation in occupancy by pairs, and therefore breeding density, was not significantly correlated with the change in occupancy from the previous year (a density-dependent influence). Heavy rain during August, in particular, and October reduced occupancy of nest temtories by pairs and this reduced the potential breeding population (a density-independent influence). Occupancy of temtories by pairs was significantly correlated with rain intensity, which accounted for 77% of the variation in occupancy. Flooding of nests, more than a reduction in food (prey availability, hunting success, etc.), appeared to result in lower occupancy by pairs in wet years.

Although behavioral researchers in marketing frequently deceive their subjects, relatively few report postexperimental debriefings. We hypothesize that researchers may avoid debriefings because (a) they feel their deceptions are so minor that debriefings are unnecessary, and (b) they fear possible negative reactions when subjects learn of the deceptions. We present the results of an experiment in which we measured debriefing effects on subjects who received such “mild” deceptions. Our results suggest that researchers have little to fear from conducting debriefings in these situations. We conclude by making several suggestions for administering debriefings and by identifying several issues concerning the effects of debriefings and deceptions that warrant future research.

(1985). A Natural Hybridization of the Brown Goshawk Accipiter Fasciatus and Grey Goshawk Accipiter Novaehollandiae in Australia, and a Comparison of the Two Species. Emu - Austral Ornithology: Vol. 85, No. 4, pp. 250-258.

Olsen, P.D. & Olsen, J. (1989). Breeding of the Peregrine Falcon Falco peregrinus: III. Weather, nest quality and breeding success. Emu 89, 6–14.Peregine Falcons laid clutches at 75% of territories...

(1987). Sexual Size Dimorphism in Raptors: Intrasexual Competition in the Larger Sex for a Scarce Breeding Resource, the Smaller Sex. Emu - Austral Ornithology: Vol. 87, No. 1, pp. 59-62.

The diet of the Australian Kestrel Falco cenchroides was studied from castings and remains of food collected during nesting, from contents of digestive tracts and from castings collected during a plague of mice. Spiders, centipedes and, in particular, insects were taken in large numbers and composed most of the diet by number. Grasshoppers and crickets, followed by beetles and moths in various developmental stages, were the most common and regular insects. Small reptiles, small birds and mice made up the vertebrate component of the diet. Mice became the major prey during a plague.

Peregrine Falcons near Canberra bred slightly earlier following a dry winter. The laying season was shorter and ended earlier when there were many raindays between June and September. The number of raindays in July and August accounted for 77% of the variation in the length of the laying period. A warm, dry winter was associated with a lengthened laying season. A longer, slightly earlier, laying season resulted in more pairs laying and therefore more young raised by the population. Late-laying pairs were only slightly less successful than early-laying pairs. Pairs with alternative nest(s), or with a well-drained nest, had a longer egg laying season, and more of them laid, than other pairs. Thus, pairs holding a territory with a high quality nest were advantaged over those that were not, because of the direct effect of rain.

The nesting chronology of one captive (5 nestings) and two wild pairs of Brown Goshawk Accipiter fasciatus, and the growth and development of twelve captive-bred and five wild-bred nestlings are described. Nest building commenced three to four weeks before egg-laying and involved both partners. Moult in the female started, at the innermost primary, about five days before the first egg was laid. Clutch size was two to four (median 3) and eggs were laid at two to four day intervals (median 2) with incubation usually commencing with the second egg. Incubation, by both sexes, lasted thirty days (range 29-31). amongst the shortest recorded for accipiters. Nestlings hatched in a coat of sparse white down which was gradually replaced by a thicker, browner, down by twelve days of age. At six days wing pins had emerged and at eight days tail pins. Fledging occurred at thirty to thirty-one days (range 28-37). Males usually reached various developmental and plumage stages a day or so before females. Wing length increased linearly between the emergence of the wing pins and thirty-five days of age and gave the best estimate of age. Weight increase was more or less sigmoid; adult weight was reached by fledging in males and slightly after fledging in females. Females were not consistently separable from males by weight until about three weeks of age, and their wing and tail length were similar to those of males until about seven weeks of age. Some methods for the estimation of age and sex are given. Growth rates were rapid in relation to body size.

Australian Kestrels are resident, partially migratory, dispersive and nomadic. Evidence was found of regular seasonal movements northward, especially, and coastally for the winter, out of the deserts for the summer, and down from higher altitudes in the south-eastem Australia for the winter. Australian Kestrels are irregular vagrants to many areas when conditions are favourable, regardless of season. Some differences in seasonal movements between age groups and sexes were found. Body weight was greatest in autumn. Slight geographic variation was found in body measurements. Wingspan, and perhaps tarsal breadth, provide the best means of separating the sexes using measurements. First year birds and adults can probably be separated in the hand, but not consistently in the field, using plumage differences.

From measurement of 472 eggs of the peregrine falcon (Falco peregrinus) collected in Australia between 1885 and 1977 inclusive, shells were thinner by 10.4 to 38% after 1947-49 and corresponded with the introduction of DDT into Australia. Victoria seemed to have the greatest mean thinning.

(1982). A Method for Reducing Illegal Removal of Eggs from Raptor Nests. Emu - Austral Ornithology: Vol. 82, No. 4, pp. 225-225.