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1.
Ecol Evol ; 14(2): e10997, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38343577

ABSTRACT

Bat pollination of Dillenia in Fiji, a genus that was presumed to be pollinated by bees, posits that other Dillenia species may be bat-pollinated, with implications for conservation and the understanding of angiosperm evolution. Botanical descriptions of some corolla behaviours ('falling as a whole') suggest bat removal of permanently closed corollas, as in D. biflora. Considering the remoteness of species of interest, we reviewed some Dillenia floral traits to hypothesise what they may mean for bat pollination of the genus. We investigated D. biflora pollen grains apertures and reviewed Dillenia literature concerning corolla behaviour and colour, and pollen apertures and presentation, including pores and staminodes. Our samples had dramatically different ratios of tricolpate to tetracolpate pollen grains, a trait that does not exclude pollination by bees. Petal colour polymorphism occurs, with mixed colours proportionately less common in flowers with corollas that open. The proportion of species with staminodes did not differ between those presumed to be pollinated by bats and others, but anthers of the former were significantly more likely to have apical pores, and stamens all had similar length or were slightly longer in the middle, whereas stamens in two distinct groups occurred in 55% of bee-pollinated species. Pollen heteromorphy may facilitate pollination by different taxa in tropical environments. However, anther apical pores and stamen uniformity are more likely to be associated with bat-pollinated species than are other morphologies. Dillenia could be a useful model to examine evolutionary aspects of colour, heteranthery, staminodes and pollen heteromorphy. Only field work will verify bat pollination and the implications of bat dependence for Dillenia species.

2.
PLoS One ; 17(2): e0262985, 2022.
Article in English | MEDLINE | ID: mdl-35113889

ABSTRACT

The Dilleniaceae is known to produce nectarless flowers pollinated by bees, but the fact that bats ingest Dillenia biflora pollen led us to question pollination assumptions for these trees. We aimed to identify the pollinators of D. biflora, check for nectar presence, and investigate potential for cleistogamy and global prevalence of this pollination system. We examined aspects of the pollination of D. biflora on two Fijian islands using video recordings, direct observations, hand pollination, measurements (flowers, bite marks, nectar), and monitoring. The flowers, receptive for one night, contained copious nectar and had permanently closed globose corollas that required removal by bats for pollination. All the 101 flowers that retained their corolla died and did not produce seeds by cleistogamy. The bat Notopteris macdonaldi was well adapted to corolla removal. Keeping corollas closed until bats manipulate the nectar-rich flowers is a beneficial strategy in high-rainfall environments with many flower parasites. We propose to name a pollination system reliant exclusively on bats "chiropteropisteusis." From clues in the literature, other species in the geographical range of Dillenia are probably chiropteropisunous. Chiropteropisteusis should be investigated in the Old-World range of Dillenia, many species of which are threatened. The remarkable "fall" of the entire corolla observed by an earlier botanist for several species in the genus is most likely attributable to bats. This discovery has important implications for the conservation of bat-dependent trees and their associated fauna, particularly considering the high level of threat faced by flying-foxes globally.


Subject(s)
Chiroptera/physiology , Dilleniaceae/physiology , Flowers/physiology , Plant Nectar/physiology , Pollen/chemistry , Pollination , Animals
3.
Sci Rep ; 10(1): 18023, 2020 10 22.
Article in English | MEDLINE | ID: mdl-33093560

ABSTRACT

Naturally occurring metals and metalloids [metal(loid)s] are essential for the physiological functioning of wildlife; however, environmental contamination by metal(loid) and plastic pollutants is a health hazard. Metal(loid)s may interact with plastic in the environment and there is mixed evidence about whether plastic ingested by wildlife affects metal(loid) absorption/assimilation and concentration in the body. We examined ingested plastic and liver concentration of eleven metal(loid)s in two seabird species: fairy (Pachyptila turtur) and slender-billed prions (P. belcheri). We found significant relationships between ingested plastic and the concentrations of aluminium (Al), manganese (Mn), iron (Fe), cobalt (Co), copper (Cu) and zinc (Zn) in the liver of prions. We investigated whether the pattern of significant relationships reflected plastic-metal(loid) associations predicted in the scientific literature, including by transfer of metals from ingested plastics or malnutrition due to dietary dilution by plastics in the gut. We found some support for both associations, suggesting that ingested plastic may be connected with dietary dilution / lack of essential nutrients, especially iron, and potential transfer of zinc. We did not find a relationship between plastic and non-essential metal(loid)s, including lead. The effect of plastic was minor compared to that of dietary exposure to metal(oid)s, and small plastic loads (< 3 items) had no discernible link with metal(loid)s. This new evidence shows a relationship between plastic ingestion and liver metal(loid) concentrations in free-living wildlife.


Subject(s)
Diet/adverse effects , Environmental Pollution/adverse effects , Liver/pathology , Metals, Heavy/toxicity , Plastics/toxicity , Polychaeta/growth & development , Animals , Liver/drug effects , Polychaeta/drug effects
4.
Glob Chang Biol ; 24(8): 3820-3836, 2018 08.
Article in English | MEDLINE | ID: mdl-29476639

ABSTRACT

The response of primary (PF) and secondary (SF) rainforests to cyclones has broad implications for servicing fauna and the resilience of forest functions. We collected fine-scale data on the reproductive phenology of plant communities in Fijian PF and SF in 12 monthly surveys before and after Cyclone Tomas (2010). We generated a resource index from the reproductive loads of 2218 trees and 1150 non-trees (>190 species) and trunk and stem diameter to assess patterns in resource abundance for nectarivores and frugivores (hereafter NF resources). We aimed to determine (i) whether species richness of NF resources differed between forests; (ii) the patterns of resilience of NF resources at community level in both forests after a cyclone; and (iii) the effect of response on NF resources for plant-servicing bats (Pteropodidae). In 12 months preceding the cyclone, NF resources were greater in PF trees; non-tree resources fluctuated and were greater in SF. Lower species richness of NF resources in SF indicated that fewer opportunities exist there for exploitation by a diverse fauna. More resources were available for bats in PF. In 12 months following the cyclone, PF flowers and fruits, and SF fruits specifically used by pteropodid bats decreased for trees. Non-tree resources were especially susceptible to the cyclone. No universal pattern of decline was associated with the cyclone; instead, some NF resources declined and others were resilient or responded rapidly to a post-cyclone environment. Both PF and SF demonstrated resilience at the community level via increased flower survival (PF) and rapid flower production (SF). Reduced species richness of NF resources in SF will compromise future resilience and response to disturbance, including for threatened pteropodid bat species. These findings are critical for long-term management of forests, given predicted increases in cyclone frequency and intensity associated with anthropogenic climate change.


Subject(s)
Chiroptera/physiology , Cyclonic Storms , Flowers , Fruit , Rainforest , Trees/physiology , Animals , Climate Change , Pollination , Tropical Climate
5.
Ticks Tick Borne Dis ; 8(5): 749-756, 2017 08.
Article in English | MEDLINE | ID: mdl-28601472

ABSTRACT

Anaplasma and Ehrlichia spp. are tick-borne pathogens that can cause severe disease in domestic animals, and several species are responsible for emerging zoonoses in the northern hemisphere. Until recently, the only members of these genera reported in Australia (A. marginale, A. centrale, and A. platys) were introduced from other continents, through the importation of domestic animals and their associated ticks. However, unique Anaplasma and Ehrlichia 16S rRNA gene sequences were recently detected for the first time in native Australian ticks, particularly in Amblyomma triguttatum subsp. ticks from southwest Western Australia (WA). We used molecular techniques to survey Am. triguttatum subsp. ticks from four allopatric populations in southern and western Australia for Anaplasma and Ehrlichia species, and described here the phylogeny of these novel organisms. An A. bovis variant (genotype Y11) was detected in ticks from two study sites; Yanchep National Park (12/280, 4.3%) and Barrow Island (1/69, 1.4%). Phylogenetic analysis of 16S rRNA and groEL gene sequences concluded that A. bovis genotype Y11 is a unique genetic variant, distinct from other A. bovis isolates worldwide. Additionally, a novel Ehrlichia species was detected in Am. triguttatum subsp. from three of the four study sites; Yanchep National Park (18/280, 6.4%), Bungendore Park (8/46, 17.4%), and Innes National Park (9/214, 4.2%), but not from Barrow Island. Phylogenetic analysis of 16S, groEL, gltA, and map1 gene sequences revealed that this Ehrlichia sp. is most closely related to, but clearly distinct from, E. ruminantium and Ehrlichia sp. Panola Mountain. We propose to designate this new species 'Candidatus Ehrlichia occidentalis'. Anaplasma bovis genotype Y11 and 'Candidatus E. occidentalis' are the first Anaplasma and Ehrlichia species to be recorded in native Australian ticks.


Subject(s)
Anaplasma/classification , Ehrlichia/classification , Ixodidae/microbiology , Phylogeny , Anaplasma/genetics , Anaplasma/isolation & purification , Animals , Bacterial Proteins/genetics , DNA, Bacterial/genetics , Ehrlichia/genetics , Ehrlichia/isolation & purification , Female , Ixodidae/growth & development , Male , Nymph/growth & development , Nymph/microbiology , RNA, Ribosomal, 16S/genetics , South Australia , Western Australia
6.
Integr Zool ; 12(3): 237-249, 2017 May.
Article in English | MEDLINE | ID: mdl-27580346

ABSTRACT

Deserts exhibit extreme climatic conditions. Small desert-dwelling vertebrates have physiological and behavioral adaptations to cope with these conditions, including the ability to seek shelter. We investigated the temperature (T) and relative humidity (RH) regulating properties of the soil cracks that characterize the extensive cracking-clay landscapes of arid Australia, and the extent of their use by 2 small marsupial species: fat-tailed and stripe-faced dunnarts (Sminthopsis crassicaudata and Sminthopsis macroura). We measured hourly (over 24-h periods) the T and RH of randomly-selected soil cracks compared to outside conditions, during 2 summers and 2 winters. We tracked 17 dunnarts (8 Sminthopsis crassicaudata and 9 Sminthopsis macroura) to quantify their use of cracks. Cracks consistently moderated microclimate, providing more stable conditions than available from non-crack points, which often displayed comparatively dramatic fluctuations in T and RH. Both dunnart species used crack shelters extensively. Cracks constitute important shelter for small animals during extreme conditions by providing a stable microclimate, which is typically cooler than outside conditions in summer and warmer in winter. Cracks likely play a fundamental sheltering role by sustaining the physiological needs of small mammal populations. Globally, cracking-clay areas are dominated by agricultural land uses, including livestock grazing. Management of these systems should focus not only on vegetation condition, but also on soil integrity, to maintain shelter resources for ground-dwelling fauna.


Subject(s)
Environment , Marsupialia , Aluminum Silicates , Animals , Australia , Clay , Soil
7.
Nature ; 539(7628): 168, 2016 11 10.
Article in English | MEDLINE | ID: mdl-27830806

Subject(s)
Environment , Australia , Humans
8.
J Environ Manage ; 112: 96-103, 2012 Dec 15.
Article in English | MEDLINE | ID: mdl-22885369

ABSTRACT

The implementation of rangeland biodiversity management strategies relies on the engagement and participation of key stakeholders, including local pastoralists (ranchers). Understanding pastoralists' knowledge of biodiversity, as well as their attitudes towards and perceptions of biodiversity management strategies, is fundamental for the development of efficacious rangeland management. This paper examines perceptions of biodiversity and land management strategies held by pastoralists in the Stony Plains region (SPR) of South Australia and reports on a survey, consisting of 45 questions, delivered to lessees and/or managers of pastoral leases within or on the edge of the SPR. Respondents generally agreed with prescribed land management strategies, but agreement did not mean that strategies were being implemented. The purchase of pastoral leases by government and/or conservation groups for biodiversity purposes was opposed strongly, which may present a barrier to collaborative land management. Pastoralists strongly agreed with several listed threats to biodiversity, but their feelings on climate-related threats were less strong. Attitudes to climate may have been influenced by above-average rainfall experienced during and preceding the survey period and by the climatic variability that characterises arid rangelands. Biodiversity conservation and the pastoral industry rely on collaborative rangeland management, non-bureaucratic communication, and an understanding among stakeholders of the attitudes and perceptions of other natural-resource users.


Subject(s)
Biodiversity , Climate , South Australia
9.
Exp Appl Acarol ; 45(1-2): 71-84, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18427936

ABSTRACT

The ornate kangaroo tick, Amblyomma triguttatum triguttatum, is invasive on Yorke Peninsula, South Australia. To assess the potential for developing comprehensive management strategies for the species, we mailed 1,000 surveys to Yorke Peninsula residents to investigate community perceptions of ticks, gather information on tick-host ecology, and assess whether or not occupation and length of residence affected whether residents had seen ticks. The response rate was 32%; most respondents (63%) had not seen ticks on Yorke Peninsula. Of those who had (n = 104), 56% had seen ticks on animals, especially lizards (31%) and kangaroos (20%); 50% had seen ticks on humans. Of the 64 respondents who believed places on Yorke Peninsula had many ticks, 56% identified Innes National Park and 75% areas on southern Yorke Peninsula. The likelihood of seeing ticks was not related to occupation. Whether respondents had seen ticks was related to length of residence on Yorke Peninsula (<10 years = 23.6%, 10-30 years = 44.0%, 31-50 years = 47.6%, 51-70 years = 30.9%, 71+ years = 21.4%). The number of respondents who had seen ticks on humans suggests that tick-borne diseases could become a public health issue on Yorke Peninsula. This finding is of particular concern because A. t. triguttatum is implicated in the epidemiology of Q fever in Queensland. Finally, respondents were unaware of the responsibility for tick management, which demonstrates a need for collaboration amongst stakeholders.


Subject(s)
Awareness , Ixodidae , Pest Control , Adult , Aged , Animals , Cross-Sectional Studies , Female , Geography , Humans , Male , Middle Aged , Occupations , Rural Population , South Australia , Time Factors
10.
Parasitol Res ; 101(5): 1323-30, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17611781

ABSTRACT

Amblyomma triguttatum triguttatum is assumed to be endemic to south-western Western Australia (including Barrow Island), Queensland (excluding Cape York Peninsula), and New South Wales, south to Dubbo and Barham. The species has been recorded on a range of mammalian hosts including macropods and domestic animals. In Queensland, A. triguttatum triguttatum is implicated in the epidemiology of Q fever. In 2000, the species was detected on southern Yorke Peninsula in South Australia. We aimed to identify A. triguttatum triguttatum's hosts through trapping, sampling of carcasses, and opportunistic capture of vertebrates on Yorke Peninsula. A. triguttatum triguttatum was removed from black rats (Rattus rattus), wild rabbits (Oryctolagus cuniculus), western grey kangaroos (Macropus fuliginosus), Tammar wallabies (M. eugenii eugenii), domesticated cats and dogs, and humans. Before this study, A. triguttatum triguttatum had not been found on black rats or rabbits in the wild. This research has implications for the management of wildlife, livestock, and visitors on Yorke Peninsula. The potential for A. triguttatum triguttatum to spread to other areas of Yorke Peninsula and South Australia is considerable, as visitors (tourists) to southern Yorke Peninsula report the presence of ticks both on themselves and among camping equipment on arriving home.


Subject(s)
Ixodidae/growth & development , Tick Infestations/parasitology , Animals , Animals, Domestic/parasitology , Animals, Wild/parasitology , Cats , Dogs , Humans , Macropodidae/parasitology , Rabbits , Rats , South Australia , Tick Infestations/veterinary
11.
Parasitol Res ; 101(5): 1203-8, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17587053

ABSTRACT

The ornate kangaroo tick, Amblyomma triguttatum triguttatum, was recently recorded on southern Yorke Peninsula, South Australia. We examined seasonal fluctuations in A. triguttatum triguttatum life stages (adult, larva, and nymph) and its distribution on the peninsula. We used in situ CO2 traps and dragging cloths to determine monthly fluctuations in free-living ticks at four sites at Innes National Park from January to December 2006, and to determine the tick's distribution on wider Yorke Peninsula. At each site, 166 m2 of ground surface were directly sampled with cloths, representing 16 1-m2 CO2 stations and three 1-m-wide 50-m transects. Adult A. triguttatum triguttatum were present in January and February and from August to December, with a peak (n=54) occurring in November. Larvae were present from February to August, with their highest density (n=3067) detected in March. Nymphs were collected from January to April and from August to December, with the highest density (n=61) detected in September. Overall, A. triguttatum triguttatum numbers were highest in March when larvae peaked, and few ticks were detected in January (summer) or July (winter). Ticks occurred at several sites on southern Yorke Peninsula, supporting their invasive status.


Subject(s)
Ixodidae/growth & development , Seasons , Animals , Larva/growth & development , Nymph/growth & development , South Australia
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