The birds and the bees and the Banksia mating trees: measuring the success of Banksia woodland restoration using genetic and ecological markers (2013)

The major threatening processes to natural ecosystemsglobally are anthropogenic, through changes in land useand degradation. A key strategy to address thesedamaging processes is to implement ecologicalrestoration programs. Ecological restoration involves therepair or creation of biological communities, ideallyrepresentative of the composition, diversity andfunctionality of the pre-disturbance habitat. Theinternational community recently committed to a newtarget to restore 15% of degraded ecosystems worldwideby 2020 (Convention on Biological Diversity 2010). Therapid growth of the restoration industry is evident, andis currently estimated to be a $2 trillion industryworldwide. To date, most endeavours have focused onrestoring vegetation and habitat structure. Consequently,restoration success has been measured againstachievements in the structural properties of ecosystems.Although pollination is a critical ecosystem service, it isyet to be fully investigated or taken into account inevaluations of restoration success (Ritchie & Krauss2012). Ultimately the fate of restored plant populationsdepends on restoring or preserving their mutualisticpollinator relationship.This study is based in the southwest of WesternAustralia, one of the most biologically diverse yet highlyfragmented and disturbed landscapes worldwide. Only30% of the Banksia woodlands on the Swan Coastal Plainremain and the decline has been most marked in the last20 years. Southwest Western Australia has the highestproportion of bird-pollinated native plants and pollinatordiversity in the world (Phillips et al. 2010) and theirimportance for outcrossing and production of geneticallyrobust outbred seed is well known. Predicting andmanaging the effects of human-induced habitatdisturbance is particularly challenging for organisms thatrely on interactions with other species for services suchas pollination and dispersal (Menz et al. 2011), and thereis increasing evidence that human disturbance negativelyimpacts plant–pollinator interactions. The implications ofthese interactions for restoration success are yet to befully investigated.The main objective of this research is to conduct agenetic and ecological assessment of restoration success,by assessing population levels of genetic diversity,structure, mating patterns, connectivity and delivery anddiversity of pollinator services in two keystone Banksiawoodland species. In order to evaluate how well we areachieving ecological restoration, we will examine howseed sourcing impacts the genetic diversity of a restoredpopulation, if the products of mating among individualsreflect that of undisturbed ecosystems, and how mightthese interactions affect the long-term viability andfunctionality of restored populations. These parameterswill be assessed and compared within restoredpopulations and their offspring to those adjacent natural,fragmented and undisturbed natural populations.Both Banksia species (Banksia attenuata and Banksiamenziesii) are preferentially outcrossing and obligatelyoutcrossing with mixed generalist pollination systems,being pollinated by nectar-feeding birds (predominantlyhoneyeaters in the family Meliphagidae), native bees,wasps and introduced honey bees (Apis mellifera). It isvital that the plant–pollinator interactions are restoredand with their pollination systems, they are most likelyto be impacted by changes in pollinator visitation andmovement.Specific aims of the research are: (i) identification ofgenetic diversity structure and mating system parametersof B. attenuata and B. menziesii using microsatellitesmarkers, in restored, natural fragmented and naturalunfragmented (control) populations; (ii) assessment ofthe diversity and abundance of pollinators in restoredand natural populations; (iii) characterisation of pollendispersal for B. attenuata and B. menziesii, assessing thedelivery of pollinator services within and betweenrestored and natural populations through geneticpaternity assignment and pollinator observations; and(iv) assessment of the importance of adjacent naturalfragments for the ecological restoration success of Banksiawoodlands.Genetic methods will be employed to estimate levelsof outcrossing, determine paternity and mating systemsby assessing the genetic structure of seeds developedfrom open-pollination. Determining paternity will allowdetection of pollen movements and therefore thedistances pollinators travelled. However, it is difficult toidentify pollinators using molecular data alone thereforepollinator mutualisms will be examined throughobserving pollinators and their movements in the field.Patterns of pollen flow and the delivery of pollinatorservices are directly related to pollinator behaviour,species and relative abundance. Therefore, the relative