Ron Wooller

Using 20 years of data (1986 to 2008), we examined relationships between oceanographic variables (Fremantle sea level (FSL) a proxy for the strength of the Leeuwin Current and sea surface temperature (SST)) and five measures of little penguin, Eudyptula minor, breeding performance near Perth, Western Australia: namely (1) the laying date, (2) the number of chicks produced per pair, (3) the proportion of eggs that hatched, (4) the overall breeding success, defined as the proportion of total eggs laid that resulted in successful fledglings and (5) chick mass at fledging. The next three years of data (2009 to 2011) were used to test the performance of our statistical predictive models. FSL provided more accurate predictions of timing of laying, whereas SST provided more accurate predictions of breeding success. A later end to laying was associated with a high FSL during the summer (December to February) before breeding. Higher SSTs in the pre-breeding period from April to May corresponded to reduced breeding success, with lower fledgling success, fewer chicks per pair and generally a lower mean mass of chicks at fledging. The models predict that future oceanographic warming is expected to reduce the breeding success of this colony of little penguins.

Context Penguin Island supports the largest colony of little penguins in Western Australia. It is subjected to a suite of anthropogenic threats because of its proximity to an increasing urban population. For effective management of the colony, it is necessary to not only have knowledge of the size of the colony, but also the population trend of the colony. Aims To demonstrate a new cost-effective method of estimating the island-wide population of penguins on Penguin Island. Methods We estimated the island-wide population by combining mark-recapture sampling over 2 years on part of the island and beach counts of penguins arriving at night around the entire island. We estimated the abundance using closed population models, allowing for sex and time effects in capture probabilities. We had four capture occasions in 2008 only, and so considered heterogeneity of capture probabilities (Mh), using the Chao heterogeneity moment estimator. The proportion of all penguins counted that arrived at the four mark-recapture sites was then used to inflate the population estimate for the whole island. Key results In all, 62% of all penguins counted used the four mark-recapture sites. In 2007, there were an estimated 2369±198 penguins, and 1543±182 in 2008. When capture heterogeneity was allowed for in 2008, this estimate increased to 2069±1172. Conclusions Fewer eggs were laid and all measures of breeding performance were lower in 2008 than in 2007. Hence, the lower population estimate is most likely to represent fewer birds attempting to breed. However, further work on population estimates is required to determine whether capture heterogeneity occurs in both good and poor breeding years. Capture rates were affected by the presence of a full moon and high tides. Implications The estimate of the population can be used as part of the basis of a long-term monitoring program needed for effective management of the penguin colony. However, such studies must be coincident with the monitoring of a suite of reproductive and foraging parameters if short-term impacts of threats are to be recognised and well managed.

The mouse‐sized marsupial Tarsipes rostratus, endemic to south‐western Australia, feeds almost exclusively on nectar and pollen. Its tongue has long filiform papillae at the tip and shorter compound papillae over much of the upper surface. These collect nectar and pollen when the long tongue, stiffened by a keratinized keel, is protruded into flowers or over pollen presenters. Pollen is scraped from the papillae by a series of combs on the roof of the mouth. A large diverticulum, off the main chamber of the stomach, may store nectar in times of surplus. Pollen is not digested in the stomach but during passage down the simple intestine, which does not have a caecum. In captive animals, pollen passed through the gut in about six hours and the percentage of grains voided which had lost their contents was related to time spent in the gut. The digestion process remains unresolved but probably takes place through the apertures in the shells of pollen grains. Tarsipes ingests large numbers of pollen grains whose contents probably provide necessary nutrients absent from nectar.

During 1978 and 1979 over 900 individuals of the mouse‐sized marsupial nectarivore Tarsipes spencerae were pitfall trapped in Banksia thickets on the south coast of Western Australia. In both years numbers were highest in spring, when nectar was most abundant and lowest during summer months when it was scarce. The larger number of males caught probably reflects their greater activity rather than their greater abundance.

The singing honeyeater, a nectar-feeding bird, is common throughout most of Australia. There is considerable geographical variation in weight, the heaviest birds (30 g) living at the highest latitudes (35°S) and the lightest birds (19 g) at the lowest latitudes (16°S). Clinal variation in weight is apparently related to climatic factors (e.g. potential evapotranspiration) in accord with Bergmann's rule. The exceptions are populations on islands and peninsulas which are about 13% heavier than those on the adjacent mainland.

The Flesh-footed Shearwater (Puffinus carneipes) is a pelagic seabird that breeds predominantly around southern Australia and New Zealand. Its breeding biology is poorly known, particularly in Western Australia where the species is known to have suffered mortality during long-line fishing operations. We studied the breeding biology of the Flesh-footed Shearwater on Woody Island, off the southern coast of Western Australia, between 2000 and 2003, from the post-migratory return of adults to the colony until the departure of the last fledglings 7 months later. Shearwaters dug single-tunnelled burrows slightly over 1 m long (1050 ± 16 mm (s.e.)) in soil >350 mm deep, during October, before embarking on an unsynchronised pre-laying exodus through November. Eggs were laid in the last week of November, and incubated over 54 ± 7 days during December and January, before hatching in mid- to late January. The fledglings left in late April-early May after spending an average 101 ± 0.9 days in the burrow. A logistic growth model, fitted to weekly measurements of skeletal body components, determined that the head, bill and tarsus grew rapidly during early burrow life, while growth of the wing was slow initially and remained incomplete at fledging. Breeding success was measured as 40% and 53% for two successive seasons, and was greater from burrows on a medium gradient than those on slighter gradients in both seasons. Although baseline data are provided here, longer term studies addressing specific demographic parameters, such as adult survival, juvenile recruitment and fecundity, are needed to assess the population status and guide management actions.

The woylie Bettongia penicillata is a small (1 kg) kangaroo-like marsupial that digs to obtain the fruiting bodies of fungi. The number of woylies in a 60 ha area of sclerophyll woodland in south-western Australia was estimated using mark-recapture at 3 month intervals over 3 successive years. The number of new diggings by woylies, determined at the same intervals, allowed an assessment of the rate of digging per individual. This varied three-fold from 38 to 114 diggings per individual per night, with no consistent seasonality. On average, each woylie displaced 4.8 tonnes of soil annually.

Seed set was examined in relation to access to inflorescences by large or small invertebrates, vertebrates, all animal visitors or none. Seed predation by insects was substantial (35-46%) and unrelated to pollinator access. The fewer the categories of animals allowed access to flowers, the greater the proportion of unpredated seeds that were aborted. Germination rates (83-96%) of filled seeds were unrelated to pollinator access, as were survival and size of seedlings at 4 months old. Overall, only 16% of seeds initiated by selfing after exclusion of all pollen vectors resulted in 4-month-old seedlings, compared with 33% of seeds initiated after access by all or larger animal visitors. Pollen and resource limitation are likely to account for only some of these findings. Rather, we suggest that preferential development of progeny fertilised by outcross pollen from other, especially distant, individuals may also play a role in reducing seed formation.

The tiny (6-12 g) honey possum Tarsipes rostratus has many adaptations to harvest and digest the nectar and pollen that are its sole food items. It occurs only in southwestern Australia, primarily near nodes of high plant species richness in coastal sandplain heathlands. Honey possums are short-lived. Both sexes have an annual mortality rate of 86% and become sexually mature about 2-3 months after leaving the pouch while not yet fully grown. Most females carry pouch-young for almost all their subsequent life and males can sire young at all times of year. The small litter size (max. 4; mean 2.4) and slow growth of pouch-young is attributed to the nutritional constraints of their diet. Multiple paternity of litters indicates a polyandrous mating system. The honey possum is solitary and sedentary, males having larger home ranges (1 280 m2) than females (700 m2). It is both phylogenetically and ecologically distinct among mammals.

Over one million pairs of seabirds breed annually on the Houtman Abrolhos island group, off the mid-western coast of Australia, the largest seabird breeding station in the eastern Indian Ocean. Eight of the 13 species that breed annually on Pelsaert Island are terns. Dietary samples (regurgitates) were collected from the five most numerous tern species from 1993 to 1999. The prey items identified were related to observations of foraging seabirds around the island. The largest species studied, the crested tern Sterna bergii, foraged mainly for reef fish over shallow reef flats near the breeding islands, as well as for schooling clupeid fish over coastal shelf waters. The smallest species, the roseate tern S. dougallii, also foraged within sight of its colonies, but over deeper waters than crested terns. Three larval fish species characteristic of continental shelf waters (a gonorhynchid, a goatfish and a bellowfish) figured prominently in the diets of roseate terns and three other tern species studied. Of these, only the sooty tern S. fuscata also ate squid and lanternfishes, foraging farthest (480–600 km) from its breeding island, off the shelf edge. The lesser noddy Anous tenuirostris and brown noddy A. stolidus took very similar taxa of prey and also overlapped considerably in their foraging ranges, about 180 km from their colonies, between the islands and the continental shelf edge. However, the lesser noddy took smaller fish than did the larger brown noddy. Although these five abundant tropical tern species, that bred sympatrically, showed some segregation in their diets and, more clearly, in their foraging ranges, considerable overlap of both aspects remained.