Floral structure, breeding system and fruit-set in the threatened sub-shrub Tetratheca juncea Smith (Tremandraceae)

Tetratheca juncea Smith (Tremandraceae) has undergone a range contraction of approx. 50 km in the last 100 years and is now listed as a vulnerable sub-shrub restricted to the central and north coast regions of New South Wales, Australia. There are approx. 250 populations in a 110 km north-south distribution and populations are usually small with fewer than 50 plants/clumps. The reproductive ecology of the species was studied to determine why seed-set is reportedly rare. Flowers are bisexual, odourless and nectarless. Flowers are presented dependentally and there are eight stamens recurved around the pistil. Anthers are poricidal, contain viable pollen and basally contain a deep-red tapetal fluid that is slightly oily. Thus flowers are presented for buzz pollinators, although none were observed at flowers during our study. The species was found to be facultatively xenogamous with only one in 50 glasshouse flowers setting seed autogamously, i.e. without pollinator assistance. Field studies revealed fertile fruit in 24 populations but production varied significantly across sites from exceedingly low (0.6 fruits per plant clump) to low (17 fruits per plant clump). Fruit-set ranged from 0 to 65 %, suggesting that pollen vectors exist or that autogamy levels in the field are variable and higher than glasshouse results. Fruit production did not vary with population size, although in three of the five populations in the south-west region more than twice as much fruit was produced as in populations elsewhere. A moderately strong relationship between foliage volume and fruit : flower ratios suggests that bigger plants may be more attractive than smaller plants to pollinators. A review of Tetratheca pollination ecology revealed that several species are poorly fecund and pollinators are rare. The habitat requirements for Tetratheca, a genus of many rare and threatened species, is discussed.     

Development of microsatellites from the rare ironstone endemic, Tetratheca paynterae ssp. paynterae and cross-species amplification

Nineteen microsatellite markers were developed from Tetratheca paynterae ssp. paynterae, a rare and endangered, leafless, perennial shrub. Twelve loci were polymorphic in T. paynterae ssp. paynterae with two to 14 alleles per locus and mean expected heterozygosity of 0.62. Primer pairs were tested on four other Tetratheca species from ironstone ranges in southern Western Australia. Ten loci were polymorphic in T. paynterae ssp. cremnobata and T. aphylla ssp. aphylla, three in T. harperi and four in T. erubescens. The level of polymorphism was adequate for studies of genetic structure and mating systems in three of the five taxa.     

评世界保护联盟新的物种受威胁分类系统草案

为了进一步了解物种受威胁的情况和发展,以加强物种保护工作,世界保护联盟制定了一个新的物种受威胁分类系统草案,把物种受威胁的程度分为９个级别,即绝灭种、野生状态下的绝灭种、极危种、濒危种、渐危种、敏感种、安全的／危险性小的种、不充分了解的种和未估价的种。本文对这个分类系统草案作了简略的评介。     

The Lord Howe Island Biodiversity Management Plan: An integrated approach to recovery planning

Summary   The Lord Howe Island Biodiversity Management Plan targeted significant species for the Lord Howe Island Group and formed the recovery plan for 30 threatened species and one endangered ecological community. The plan addressed threats and management actions relevant to the Lord Howe Island Group's overall biodiversity, with a particular focus on rare and significant species and communities. The Biodiversity Management Plan approach enabled holistic and cost-effective planning for the management of biodiversity on Lord Howe Island. We describe the approach, as applied to Lord Howe Island, including the utilization of expert and community knowledge, species research data and GIS innovations.     

Going with the flow? Threatened species management and legislation in the face of climate change

Summary   The potential impacts of climate change on threatened species, populations and communities are considered. It is suggested that minor changes to legislation will be required to address the consequences of movement of threatened species but that threatened species legislation will remain relevant as an important tool for prioritizing conservation actions. The importance of taking proactive steps now to permit future movement of species and communities across fragmented landscapes is emphasized.     

列入《濒危野生动植物物种国际贸易公约》附录的物种的新标准

ＣＩＴＥＳ（濒危野生动植物国际贸易公约）是一个通过控制贸易的方法来维护物种生存及其持续利用的国际法规,其附录中所列的物种是重点管理的对象,主要根据现有的Ｂｅｒｎｅ标准来确定。但是,长期的实践证明,它已不能满足实际的需要。１９９２年６月ＣＩＴＥＳ常务委员会要求世界保护联盟协助制定一个简明、实用、科学和客观的新标准,本文对此作一简介和讨论。     

New insights into patterns of coral spawning on Western Australian reefs

On reefs around Australia, coral mass spawning typically occurs during the austral spring (October/November) on the east coast, and during autumn (March/April) on the west coast. However, to investigate the incidence of a secondary spawning event in spring on the west coast, the reproductive state of corals was assessed on two reefs. The results indicated that of the 29 species of Acropora investigated, multiple colonies of 11 species spawned in late spring or in early summer, in contrast to previous reports of spawning during autumn. Additionally, of four species that were followed through time at one reef, two spawned in both spring and autumn, however, individual colonies had only one gametogenic cycle. Within a single site, conspecific colonies were reproductively isolated and may not interbreed, potentially representing the initial stage of sympatric speciation in these populations.     

The complex nature of headland shrub encroachment: The case of Headland Zieria (Zieria prostrata)

Headland Zieria (Zieria prostrata) is an endangered species restricted to four headlands with a potential population of 1000 individuals. The species also occurs within the endangered ecological community Themeda grassland on sea cliffs and coastal headlands in the New South Wales North Coast, Sydney Basin and South East Corner Bioregions. Shrub encroachment of native species is perceived as a threatening process within these grasslands, and also to the unique species within them, such as Headland Zieria. Suggested management actions for the community and Headland Zieria include the removal of other shrubs by frequent fire or mechanical means. We conducted a survey and correlative analyses to test the validity of these proposed actions. We provide evidence that Headland Zieria is facilitated by a higher density of nearby shrubs which may provide protection from the elements and decrease competition from other understorey species but is eventually out competed by them when the grassland fully transitions to a Banksia shrubland. We suggest that Headland Zieria is an ecotonal specialist that may require an invasion front of shrubs and/or isolated patches. The implementation of fire and/or overstorey shrub removal may be detrimental where populations of Headland Zieria occur. Our study highlights the need to look more closely at interactions before management actions changing vegetation structure and composition are implemented.