Miconia Calvescens Research Articles

Preference for an invasive fruit trumps fruit abundance in selection by an introduced bird in the Society Islands, French Polynesia

Introduced plants with fleshy fruit can alter the dietary decisions of frugivorous birds in their novel ranges by producing fruit of higher quality or by producing fruit in greater abundance. We used fruit choice experiments with wild-caught captive Red-vented Bulbuls (Pycnonotus cafer) on the tropical Pacific island of Moorea, French Polynesia, to determine whether this bird prefers the fruit of a highly invasive tree (Miconia calvescens) over three other fruit (one alien, two native) and to determine whether birds would eat less preferred fruit when it was more abundant than preferred fruit. Birds showed consistent preferences, and chose M. calvescens more than any other species. Birds selected more abundant fruit first when a single species was presented. However, when both fruit species and abundance were modified simultaneously, patterns of preference for particular species remained intact while the response to abundance disappeared. Results imply that dietary preferences are more important than small-scale variations in abundance for fruit selection. The strong preference for M. calvescens suggests that Bulbuls will select the fruit even in habitats where it is rare.

Erosion Potential under Miconia calvescens Stands on the Island of Hawai‘i

AbstractThis study provides evidence that Miconia calvescens has the potential to accelerate surface erosion in stands where it invades by (i) reducing under‐canopy light levels, thereby reducing the establishment of ground cover vegetation, and (ii) producing highly erosive throughfall drops on large leaves in a single‐layer canopy. The throughfall energy in a stand of invasive miconia on the Island of Hawai‘i (USA), assessed by measuring the drop size and drop velocity distributions with a laser disdrometer, was significantly higher than that in a stand of native ‘ōhi‘a (Metrosideros polymorpha) and ambient rainfall. Median throughfall drop size for miconia (3·83 mm) was twice that of ambient rainfall (1·62 mm). Highly erosive throughfall resulted from large drops forming on large miconia leaves and relatively high fall velocities associated with the single‐story miconia canopy. In contrast, multi‐storied natural ‘ōhi‘a had a larger median drop size; however, a lower fall height reduced throughfall effective kinetic energy. Furthermore, the effective kinetic energy for miconia was high because large drops (> 3·8 mm) with high kinetic energy accounted for 60 per cent of the total energy (versus 30–40 per cent for other vegetation types). Consequently, unit kinetic energy of throughfall was 28 J m−2 mm−1 under miconia, compared with <24 J m−2 mm−1 for rainfall and <20 J m−2 mm−1 under ‘ōhi‘a. These data, combined with the observation of limited protective ground cover under miconia, show the potential for accelerated erosion occurring on forest floors in stands of invasive miconia. Copyright © 2013 John Wiley & Sons, Ltd.

Ditylenchus gallaeformans sp. n. (Tylenchida: Anguinidae) – a neotropical nematode with biocontrol potential against weedy Melastomataceae

Ditylenchus gallaeformans sp. n. was found on several hosts at numerous locations in Brazil and Costa Rica. In its native habitats it attacks several genera in the Melastomataceae, including two species ranked as among the worst invasive weeds of Pacific island forests, namely Miconia calvescens and Clidemia hirta. The new species causes a severe disease on infected plants involving the formation of gall-like structures on infected leaves, inflorescences and stems, and may cause significant impact on its hosts. Morphological study using light and scanning electron microscopy and analysis of the partial 18S rRNA, the D2-D3 expansion fragments of 28S rRNA and the ITS rRNA gene sequences showed little variations between populations from different hosts or geographical origins. The molecular study revealed that the new species is related to D. drepanocercus, which was recently found in association with M. calvescens but causing angular leaf spots on this host. Ditylenchus gallaeformans sp. n. is distinguished from D. drepanocercus by having a bursa reaching the tail tip (vs covering around 50% of tail in D. drepanocercus) and a conical tail, regularly tapering towards a variable tip (vs tail with a distinctive apical falciform appendage in both sexes in D. drepanocercus). PCR with species-specific primers was developed for diagnostics of both Ditylenchus species. Ditylenchus gallaeformans sp. n. deserves further investigation as a potential biocontrol agent against M. calvescens and C. hirta.

Lepidopterans as Potential Agents for the Biological Control of the Invasive Plant,Miconia calvescens

This work investigated eight species of Lepidoptera associated with Miconia calvescens DC. (Myrtales: Melastomataceae) in Brazil, including six defoliators, Salbia lotanalis Druce (Lepidoptera: Pyralidae), Druentia inscita Schaus (Mimallonidae), Antiblemma leucocyma Hampson (Noctuidae), three Limacodidae species, a fruit borer Carposina cardinata Meyrick (Carposinidae), and a damager of flowers Pleuroprucha rudimentaria Guenée (Geometridae). Based on host specificity and the damage caused to plants, S. lotanalis and D. inscita are the most promising species for biological control of M. calvescens. Furthermore, if C. cardinata and P. rudimentaria have host specificity in future tests, these caterpillars could also be considered as appropriate biocontrol agents.

The Life History and Immature Stages of the WeevilAnthonomus monostigmaChampion (Coleoptera: Curculionidae) onMiconia calvescensDC (Melastomataceae)

Abstract. We describe and illustrate the life history and immature stages of Anthonomus monostigma Champion (Curculionidae: Curculioninae: Anthonomini). This weevil is a fruit borer in Miconia calvescens DC (Melastomataceae), a Neotropical tree that is invasive in Pacific islands. The larva has three instars, and development from egg to adult requires approximately two months. In Costa Rica, A. monostigma larvae were found in three Miconia species, and adults fed only on Miconia species. Host relationships of the A. monostigma group suggest that this group could be related to the A. partiarius and A. albocivitensis groups (sensu Clark 1992, 1993b). The potential of A. monostigma as a biological control agent is discussed.

An invasive tree alters the structure of seed dispersal networks between birds and plants in French Polynesia

AbstractAim We studied how the abundance of the highly invasive fruit‐bearing tree Miconia calvescens DC. influences seed dispersal networks and the foraging patterns of three avian frugivores.Location Tahiti and Moorea, French Polynesia.Methods Our study was conducted at six sites which vary in the abundance of M. calvescens. We used dietary data from three frugivores (two introduced, one endemic) to determine whether patterns of fruit consumption are related to invasive tree abundance. We constructed seed dispersal networks for each island to evaluate how patterns of interaction between frugivores and plants shift at highly invaded sites.Results Two frugivores increased consumption of M. calvescens fruit at highly invaded sites and decreased consumption of other dietary items. The endemic fruit dove, Ptilinopus purpuratus, consumed more native fruit than either of the two introduced frugivores (the red‐vented bulbul, Pycnonotus cafer, and the silvereye, Zosterops lateralis), and introduced frugivores showed a low potential to act as dispersers of native plants. Network patterns on the highly invaded island of Tahiti were dominated by introduced plants and birds, which were responsible for the majority of plant–frugivore interactions.Main conclusions Shifts in the diet of introduced birds, coupled with reduced populations of endemic frugivores, caused differences in properties of the seed dispersal network on the island of Tahiti compared to the less invaded island of Moorea. These results demonstrate that the presence of invasive fruit‐bearing plants and introduced frugivores can alter seed dispersal networks, and that the patterns of alteration depend both on the frugivore community and on the relative abundance of available fruit.

Survival patterns under Costa Rican field conditions of the gregarious caterpillar Euselasia chrysippe (Lepidoptera: Riodinidae), a potential biological control agent of Miconia calvescens (Melastomataceae) in Hawaii

Survival of Euselasia chrysippe, a natural herbivore of Miconia calvescens, was investigated under field and laboratory conditions in Costa Rica as part of a biological control program in Hawaii. Following its introduction to Pacific islands, M. calvescens has become a dominant invasive species and the gregarious caterpillar of E. chrysippe has emerged as a promising biological control candidate. Under laboratory conditions, survivorship from egg to adult was 63%. E. chrysippe produced viable clutches in an experimental field plot. Similar clutch sizes occurred in both natural habitats and the experimental plot. Stage-specific life tables encompassing two years in the experimental plot indicate that larval survivorship from egg to the end of the sixth instar was about 10%. Egg parasitism was low in natural habitats and nil under experimental conditions. Larval group sizes were similar in natural and experimental field conditions, suggesting that survivorship is similar in both environments. During the coldest dry period no larvae survived past the fifth instar. Rainfall was a limiting factor for the survivorship of E. chrysippe in the experimental plot, but temperature appears to be the factor that would limit the effect of E. chrysippe on M. calvescens in Hawaii. Efforts should be invested in natural quarantine facilities to provide a testing ground for this species in target environments.

Getting here from there: testing the genetic paradigm underpinning introduction histories and invasion success

AbstractAim To explore the potential of genetic processes and mating systems to influence successful plant invasions, we compared genetic diversity of the highly invasive tropical treelet,Miconia calvescens,in nine invasive populations and three native range populations. Specifically, we tested how genetic diversity is partitioned in native and invaded regions, which have different invasion histories (multiple vs. single introductions). Lastly, we infer how levels of inbreeding in different regions impact invasion success.Location Invaded ranges in the Pacific (Hawaii, Tahiti, New Caledonia) and Australia and native range in Costa Rica.Methods Genetic diversity was inferred by analysing variation at nine microsatellite loci in 273 individuals from 13 populations ofM. calvescens. Genetic structure was assessed usingamova, isolation by distance (IBD) within regions, a Bayesian clustering approach, and principal coordinates analysis.Results Microsatellite analysis revealed that invaded regions exhibit low levels of allelic richness and genetic diversity with few private alleles. To the contrary, in the native range, we observed high levels of allelic richness, high heterozygosity and 78% of all private alleles. Surprisingly, despite evident genetic bottlenecks in all invasive regions, similarly high levels of inbreeding were detected in both invasive and native ranges (FIS: 0.345 and 0.399, respectively). Bayesian clustering analysis showed a lack of geographical structure in the Pacific and evidence of differing invasion histories between the Pacific and Australia. While Pacific populations are derived from a single introduction to the region, multiple introductions have taken place in Australia from different source regions.Main conclusions Multiple introductions have not resulted in increased genetic diversity forM. calvescensinvasions. Moreover, similar inbreeding levels between native and invaded ranges suggests that there is no correlation between levels of inbreeding and levels of standing genetic diversity forM. calvescens.Overall, our results show that neither inbreeding nor low genetic diversity is an impediment to invasion success.

Restoring habitat for native and endemic plants through the introduction of a fungal pathogen to control the alien invasive tree Miconia calvescens in the island of Tahiti

Success of biological control programs is commonly assessed by studying the direct negative impacts of released agents on the target invasive species. Very few quantitative studies have focused on the indirect positive effects on native biodiversity. In this study, we monitored the response of the plant community (both native and alien species) in permanent plots located in four different sites in montane rainforests of the tropical island of Tahiti (South Pacific) severely invaded over decades by the alien invasive tree Miconia calvescens DC (Melastomataceae), after the release of a defoliating fungal pathogen Colletotrichum gloeosporioides f. sp. miconiae Killgore & L. Sugiyama. Results of five years of monitoring showed that total native and endemic species richness and plant cover increased in all sites and plots. Partial defoliation of miconia canopy trees (between 6% and 36%) led to significant recruitment of light-demanding pioneer species, but also to the appearance of some semi-shade and shade tolerant rare endemic species. Native ferns and angiosperms remained dominant (ca. 80%) in the forest understorey during the monitoring period. Colonization by a small number of alien plant species occurred in one permanent plot located at the lower elevation. We conclude that biological control may be considered a tool for partial habitat restoration and recovery of native and endemic species, but long-term monitoring is needed to confirm the stability and resilience of the “novel plant assemblage”.

Persistence and spread in a new landscape: Dispersal ecology and genetics of Miconia invasions in Australia

Biological invasions have been identified as a key threatening process with significant negative impacts for global biodiversity. To better understand the process of plant invasion and spread for woody weeds in Australia’s rainforests, we ask how individuals and species move across the landscape and whether genetic bottlenecks constrain invasion potential in three related Melastomes, Miconia calvescens, Miconia nervosa and Miconia racemosa. All three species are actively being eradicated, and while they have similar growth forms, fruit type and they occur in similar habitats, the nature of their invasions differs. M. calvescens, the largest of the three species, is present at more than 40 sites across the Wet Tropics, whereas M. nervosa and M. racemosa are each known from just a single location. Even though these weedy Melastomes were relatively recently introduced to Australia, they are well dispersed by native frugivores (up to 1–2 km). Genetic diversity is lower in M. calvescens and M. racemosa than in M. nervosa, which is consistent with few founding individuals (or closely related individuals) being responsible for introduction in those populations. In contrast, the M. nervosa population was likely founded by more individuals or from multiple sources that were less closely related. Interestingly, multiple introductions of M. calvescens have not resulted in increased genetic diversity; and the more genetically diverse M. nervosa has, at least to date, failed to demonstrate the level of invasiveness characterised by M. calvescens. One broader application of research such as this is the possibility of applying genetic tools to detect unknown parental plants in the landscape that have not been previously identified or located.

A SVM-based model for predicting distribution of the invasive tree Miconia calvescens in tropical rainforests

Advances in spatial and spectral resolution of sensors can be useless to detect directly understory and subcanopy species but make remote sensing of some ecosystems components increasingly feasible. We propose to use support vector machines (SVM) to integrate multisource-derived biophysical descriptors (overstory plant species, physiography and climate) for the indirect detection of the small invasive tree Miconia calvescens in tropical rainforests on the island of Tahiti (South Pacific). Our model consists in classifying overstory plant species from an optical Quickbird scene, with the output then used in a subsequent fusion process with digital elevation model (DEM) extracted physiographic and climatic descriptors. A range of accuracy metrics was calculated to assess the SVM-based model which widely outperforms the commonly used GARP model. Biophysical descriptors alone are necessary and sufficient to explain M. calvescens distribution and suggest that the potential invaded area is currently saturated in our study site on Tahiti. Rainfall, elevation and slope steepness are the major variables explaining the species distribution. In addition, our results show that morning insolation plays a critical role on M. calvescens height whether it is restricted to the subcanopy or reaches the forest surface. The model can be used to map the potential distribution of M. calvescens in areas where it has been recently introduced and rapidly spreading, such as in the Hawaiian islands, New Caledonia and Australia or in other French Polynesian islands. It also may be adapted to detect other species (plants or animals, alien invasives or rare endemics) in the understory and subcanopy of forest ecosystems.

Diversity, Ecology and Herbivory of Hairstreak Butterflies (Theclinae) Associated with the Velvet Tree,Miconia calvescensin Costa Rica

Larvae of three species of hairstreak butterflies in the subfamily Theclinae (Lepidoptera: Lycaenidae) were found feeding on developing inflorescences, flower buds, and immature fruits of the velvet tree, Miconia calvescens DC. (Myrtales: Melastomataceae) in Costa Rica. Erora opisena (Druce), Parrhasius polibetes (Cramer), and Temecla paron (Godman and Salvin) were studied in association with M. calvescens, an uncommon tree in its natural range in the neotropics and a target for biocontrol as an invader in Pacific islands. Host plant use by the three theclines was similar, with eggs being laid on inflorescences and cryptic larvae remaining there throughout development. Feeding damage by E. opisena was most abundant in pre-flowering M. calvescens, when 23% of inflorescences showed feeding damage characteristic of this species. Feeding damage by T. paron peaked at flowering, when 30% of inflorescences were affected. At field sites, E. opisena and T. paron damaged an average of 26 and 18% of each attacked inflorescence, respectively. In cage experiments, individual third- and fourth-instar larvae of E. opisena damaged an average of 24 and 21% of an inflorescence before pupating, respectively. This study provides the first host plant record for E. opisena and T. paron, the first record of P. polibetes feeding on Melastomataceae, and the first records of E. opisena and T. paron presence in Costa Rica.

Biology and Host Preferences of Cryptorhynchus melastomae (Coleoptera: Curculionidae), a Possible Biocontrol Agent for Miconia calvescens (Melastomataceae) in Hawaii

The introduced plant Miconia calvescens (Melastomataceae) poses a grave threat to Hawaii's native ecosystems and biodiversity. One potential candidate for classical biological control is Cryptorhynchus melastomae (Coleoptera: Curculionidae: Cryptorhynchinae), a stem-boring weevil from Central and South America. This weevil feeds on M. calvescens in its native Costa Rica and has been successfully reared under greenhouse conditions. Comparison of its environmental conditions in Costa Rica with those in the Miconia infested areas of Hawaii indicates the latter is a suitable habitat for C. melastomae. C. melastomae has one or two generations per year. Adults feed on new stems, petioles, leaf buds, veins, and lamina, whereas larvae mine the stem until pupation. Adults appear to prefer saplings for oviposition and feeding. Under greenhouse conditions both adults and larvae can seriously damage and kill small M. calvescens. Preliminary host testing indicates that C. melastomae may be family specific on Melastomataceae. However, because Hawaii lacks native melastomes and has many other serious melastome weeds, a family specific insect may be suitable as a biocontrol agent in this case.

Conservation benefits of biological control: The recovery of a threatened plant subsequent to the introduction of a pathogen to contain an invasive tree species

Biological control using host-specific natural enemies is sometimes the only long-term and cost-effective option to contain dominant invasive alien species in natural ecosystems. To assess biocontrol success, most monitoring studies focus on the negative impacts of the released biocontrol agents on the target invasive species. Very few studies have shown the conservation benefits, i.e. their positive effects on the recovery of native species and habitats. A fungal pathogen ( Colletotrichum gloeosporioides f. sp. miconiae) was successfully released on the island of Tahiti (South Pacific) to control the dominant invasive tree Miconia calvescens which forms dense monospecific stands in native rain- and cloud forests. The pathogen causes a leaf disease leading to partial (5–35%) defoliation of Miconia canopy trees. We studied the demographical parameters of the rare endemic sub-shrub Ophiorrhiza subumbellata, growing in the understory of montane cloud forests invaded by Miconia. We compared Ophiorrhiza populations in 13 plots set up in two sites located between 950 and 1000 m elevation, having the same Miconia invasion degree but different levels of leaf damage . Our results showed that, whereas the total population density of Ophiorrhiza is not affected, plants’ growth and fertility were significantly higher in more defoliated Miconia forests. A 3-year-long survey of Ophiorrhiza population at one study site indicated that the number of seedlings and juvenile plants increased, suggesting better recruitment and survival. This study demonstrates that biological control has contributed to the recovery of an endemic plant directly threatened by an invasive species, and may be considered as an important management tool for the partial restoration of native forests.

Frugivory by introduced black rats (Rattus rattus) promotes dispersal of invasive plant seeds

Oceanic islands have been colonized by numerous non-native and invasive plants and animals. An understanding of the degree to which introduced rats (Rattus spp.) may be spreading or destroying seeds of invasive plants can improve our knowledge of plant-animal interactions, and assist efforts to control invasive species. Feeding trials in which fruits and seeds were offered to wild-caught rats were used to assess the effects of the most common rat, the black rat (R. rattus), on 25 of the most problematic invasive plant species in the Hawaiian Islands. Rats ate pericarps (fruit tissues) and seeds of most species, and the impacts on these plants ranged from potential dispersal of small-seeded (≤1.5 mm length) species via gut passage (e.g., Clidemia hirta, Buddleia asiatica, Ficus microcarpa, Miconia calvescens, Rubus rosifolius) to predation where <15% of the seeds survived (e.g., Bischofia javanica, Casuarina equisetifolia, Prosopis pallida, Setaria palmifolia). Rats consumed proportionally more seed mass of the smaller fruits and seeds than the larger ones, but fruit and seed size did not predict seed survival following rat interactions. Although invasive rat control efforts focus on native species protection, non-native plant species, especially those with small seeds that may pass internally through rats, also deserve rat control in order to help limit the spread of such seeds. Black rats may be facilitating the spread of many of the most problematic invasive plants through frugivory and seed dispersal in Hawaii and in other ecosystems where rats and plants have been introduced.

Description of the immature stages and life history of Euselasia (Lepidoptera: Riodinidae) on Miconia (Melastomataceae) in Costa Rica

The immature stages and life histories of Euselasia chrysippe (Bates, 1866) and E. bettina (Hewitson, 1869) are described, providing the first detailed morphological characters for the subfamily Euselasiinae. The larvae of Euselasia chrysippe and E. bettina specialize on several species of Miconia (Melastomataceae). The eggs are stalked (the first reported case of such in Lepidoptera) and laid in clusters on the underside of leaves. The larvae are gregarious and feed, rest, molt, and pupate ‘synchronously’. Both species have six larval instars which exhibit processionary behavior throughout their development. SD2 setae on the prothoracic shield are sensitive to airborne vibrations and are related to the head-flicking behavior exhibited by larvae while feeding, perhaps as a defensive strategy to deter attacks by parasitoids. Several morphological characters of first instar larvae are unique among Lepidoptera: extra setae, bifurcated dorsal setae on A1–8, and various organs. Sixth instar larvae possess subcircular plates on the dorsolateral surfaces of all segments of the thorax and abdomen. These smooth plates have a metallic-blue iridescence that is structural in nature. Pupation occurred singly or gregariously under laboratory conditions. The total duration of the life cycle under laboratory conditions lasted up to eight weeks. New records of parasitoids for Euselasia include Encarsia and Telenomus from eggs. A list of host plants recorded for Euselasiinae, a summary of parasitoid records for Euselasia, and summary tables of unique organs and setae of immature stages are provided. Euselasia chrysippe and E. bettina are currently considered potential biocontrol agents for Miconia calvescens DC in Hawaii.

Applying a simulation model to the management of an infestation of Miconia calvescens in the wet tropics of Australia

Hester SM, Brooks SJ, Cacho OJ &amp; Panetta FD (2010). Applying a simulation model to the management of an infestation of Miconia calvescens in the wet tropics of Australia. Weed Research50, 269–279.SummaryA simulation model that combines biological, search and economic components is applied to the eradication of a Miconia calvescens infestation at El Arish in tropical Queensland, Australia. Information on the year M. calvescens was introduced to the site, the number of plants controlled and the timing of control, is used to show that currently there could be M. calvescens plants remaining undetected at the site, including some mature plants. Modelling results indicate that the eradication programme has had a significant impact on the population of M. calvescens, as shown by simulated results for uncontrolled and controlled populations. The model was also used to investigate the effect of changing search effort on the cost of and time to eradication. Control costs were found to be negligible over all levels of search effort tested. Importantly, results suggest eradication may be achieved within several decades, if resources are increased slightly from their current levels and if there is a long‐term commitment to funding the eradication programme.

Biology of the leaf roller Salbia lotanalis and its impact on the invasive tree Miconia calvescens

Miconia calvescens (Melastomataceae) is an invasive alien tree in native forests on some Pacific islands and a potentially invasive species in Australia. Searches for potential classical biocontrol agents have been undertaken for over a decade in the centre of origin (Central and South America). Salbia lotanalis (Lepidoptera: Pyralidae) is a leaf roller which has been recognized as a promising classical biocontrol agent for M. calvescens. This paper presents the biology and an impact study of S. lotanalis on M. calvescens. Life table parameters showed that S. lotanalis has a high reproductive capacity, with up to six generations a year. Miconia calvescens seedlings attacked by S. lotanalis caterpillars had their growth rate significantly reduced. Seedlings subjected initially to a high level of defoliation (80%) caused by caterpillars had leaf fall and a lower leaf area than controls after 210 days. Considering the high population growth rate and significant impact on young plants, S. lotanalis appears to have a high potential for use as a classical biological control agent to be used against M. calvescens.

Additions to the mycobiota of the invasive weed Miconia calvescens (Melastomataceae)

Miconia calvescens (Melastomataceae) is a shrub or small tree native to the Neotropics that has become one of the worst invaders of forest ecosystems, particularly in Pacific islands such as Hawaii and French Polynesia. It has been a target for biological control for more than 10 y, both with arthropod and pathogen natural enemies. Until now Colletotrichum gloeosporioides f. sp. miconiae was the only organism to be used in biological control against this weed. This fungus was introduced both in Hawaii and in French Polynesia in the late 1990s/early 2000s, where it has caused some damage to the weed, but it became evident that additional agents are needed to achieve adequate control. Exploratory surveys for plant pathogens as potential biocontrol agents of M. calvescens were undertaken in Brazil, Costa Rica and Ecuador and yielded a diverse list of pathogens, including one phytoplasma, two nematodes, one oomycete and numerous fungi. A study including the description of five fungal species found attacking M. calvescens was published recently. Herein the following additional fungi also belonging to the mycobiota of M. calvescens are described: Hyalosphaera ornata sp. nov, Microsphaeropsis miconiae sp. nov., Myrothecium miconiae sp. nov., Phyllachora miconiiphila sp. nov., as well as Hyalosphaera miconiae, Lembosia melastomatum and Microsphaeropsis clidemiae, which are recorded here for the first time on this host. Although preliminary our observations of damage to M. calvescens caused by these seven fungal species did not indicate any potential for use in classical biological control.

Hawaiian Residents’ Preferences for Miconia Control Program Attributes Using Conjoint Choice Experiment and Latent Class Analysis

Invasive species control or eradication is an important issue. On the islands of Hawaii, this problem is exceedingly evident when it comes to Miconia calvescens (Miconia). Adequate funding is needed to control or eradicate this invasive plant, but with the limited amount of funding available for the fight against Miconia, it is important to make sure that the fund is being spent in a way that addresses the needs or preferences of the Hawaiian residents. Using the conjoint choice experiment method, we designed a survey that would measure the Hawaiian residents' willingness to support Miconia control program attributes. The attributes focused on were cost, biodiversity loss, extent of spread and soil erosion. Latent class approach was used to assess the surveyed population to see the different preferences by individual classes. The results show three different classes or groups of individuals with varying preferences for a control program of which cost and erosion were the top preferred attributes among the classes. These groups were defined by their socio-demographics of income, the length of residency and exposure to farming/gardening activities. Even with a preference for lower cost, a group showed willingness to pay more ($2.40) for a program that reduces erosion from high to low. Finally, the biodiversity attribute had very low consideration from a majority of the respondents showing the need for educating the public regarding its importance in preserving the unique environment in Hawaii.