Heise-Pavlov S.R.,Center for Rainforest Studies |
Jackrel S.L.,Center for Rainforest Studies |
Jackrel S.L.,The College of New Jersey |
Meeks S.,Center for Rainforest Studies |
Meeks S.,Whitman College
Australian Mammalogy | Year: 2011
Success of conservation efforts of large and cryptic mammals is often limited due to a lack of knowledge of their habitat preferences. This study investigates factors that affect the habitat selection of the rare Lumholtz's tree-kangaroo, Dendrolagus lumholtzi, using signs of its activity. The presence and absence of scratch marks on tree trunks and faecal pellets within a 100-cm radius around them were surveyed on 23ha within a 65-ha large fragment of rainforest on the Atherton Tablelands, north-eastern Australia in order to classify trees as 'actively used' or 'inactive'. Structural features of the 315 surveyed tree trunks were also recorded. Using discriminant function analysis, 'actively used' trees were found to have no epiphytes on the main trunk, less obstruction by neighbouring trees, shrubs or lianas within a 0.5-m radius of the trunk (particularly in the eastern direction), and a smaller diameter at breast height than 'inactive' trees. Smaller tree trunks and less obstruction may facilitate a more rapid movement into the canopy as well as provide potential escape routes from predators. More specific knowledge on factors that affect habitat selection of the Lumholtz' tree-kangaroo will help in a reclassification of the threatened status of this species and assist in more effective conservation efforts. © 2011 Australian Mammal Society.
Deines J.M.,Center for Rainforest Studies |
Deines J.M.,University of Notre Dame |
Hellmann J.J.,University of Notre Dame |
Curran T.J.,Center for Rainforest Studies |
Curran T.J.,Lincoln University at Christchurch
Australian Journal of Botany | Year: 2011
Drought affects the distribution of plant species in tropical forests and will likely increase under climate change. Future rainforest composition may be determined by species' abilities to withstand increased drought incidence, particularly at the vulnerable seedling stage. A greenhouse drought survival experiment was conducted on seedlings of three common evergreen tree species from Australia's Wet Tropics to assess species' drought survival. This was then related to five functional traits to evaluate the relative importance of desiccation tolerance (ability to persist through drought) and desiccation delay (ability to postpone drought stress) in drought survival. Among the three species examined, delay traits (leaf shedding, root-to-shoot ratio and stem saturated water content) corresponded with experimental drought survival better than tolerance traits (specific leaf area, stem density). Notably, we found differential leaf shedding among these evergreen species and a positive correlation between percent leaf loss and drought survival among individuals across all species (R 2=0.42). If this pattern holds with greater species replication, it suggests that desiccation delay, particularly via leaf shedding, is important for drought survival even in nominally evergreen species. We suggest that finer classifications of deciduousness such as percent leaf loss under drought stress may be useful in predicting species' responses to drought conditions. © 2011 CSIRO.
Heise-Pavlov S.,Center for Rainforest Studies |
Anderson C.,Wildlife Habitat |
Moshier A.,Clark University
Australian Mammalogy | Year: 2014
Food preferences of the arboreal Lumholtz's tree-kangaroo (Dendrolagus lumholtzi), endemic to the tropical rainforests of north-eastern Australia, are largely unknown, but are likely to affect the movements of this mammal within its home range and across a fragmented landscape. Food selection was investigated by applying a consumption ranking system to 35 browse species provided to six captive animals throughout different years. Animals consumed foliage from a wide range of rainforest tree species, but at different intensities, suggesting that Lumholtz's tree-kangaroo is a selective folivore. All studied animals showed a general preference for the foliage of the northern olive (Chionanthus ramiflorus) and the umbrella tree (Schefflera actinophylla) throughout the year while foliage from acacias (Acacia spp.), milky pine (Alstonia scholaris) and pink ash (Alphitonia petriei) was less frequently consumed. Foliage from figs (Ficus spp.) and the northern tamarind (Diploglottis diphyllostegia) was consumed at higher rates only at certain times of the year, suggesting the existence of seasonal preferences. The knowledge of general and seasonal food preferences of this large arboreal mammal may allow a better prediction of animal movements and therefore can assist in conservation efforts. Recommendations for the integration of these findings in restoration projects are given. © Australian Mammal Society 2014.
Heise-Pavlov S.R.,Center for Rainforest Studies |
Paleologo K.,Wellesley College |
Glenny W.,Gonzaga University
Journal of Pest Science | Year: 2014
The development of biological control measures to reduce the impact of invasive species is a desired goal. Rhabdias species have recently been advocated as biological control agents for invasive anurans. This study describes a field-based approach to support laboratory results on the potential impact of the lung nematode Rhabdias pseudosphaerocephala on the prey consumption of its host, the invasive cane toad (Rhinella marina, Bufonidae). Toads were sampled from various populations in the Wet Tropics of Australia during the wet seasons of 2010 and 2012. Consumed prey items were counted in 212 cane toads and identified to class and order levels and the number of lung nematodes was counted for each toad. The number of R. pseudosphaerocephala in free-ranging cane toads affected negatively the diversity of prey items consumed, but was not related to the number of prey items or the number of ants consumed. The results suggest that infection of free-ranging cane toads by the lung nematode reduces their range of prey items. Possible reasons could be a reduced locomotor activity resulting in changes of foraging modes of infected toads which was reported from some laboratory trials. Infection of cane toads by R. pseudosphaerocephala may therefore have the potential to alter the impact of cane toads on invertebrate communities and their competition for food resources with native Australian anurans. © 2013 Springer-Verlag Berlin Heidelberg.
Elgar A.T.,Griffith University |
Freebody K.,Griffith University |
Freebody K.,Tablelands Community Revegetation Unit |
Pohlman C.L.,Center for Rainforest Studies |
And 2 more authors.
Frontiers in Plant Science | Year: 2014
Combating the legacy of deforestation on tropical biodiversity requires the conversion to forest of large areas of established pasture, where barriers to native plant regeneration include competition with pasture grasses and poor propagule supply (seed availability). In addition, initial woody plants that colonise pasture are often invasive, non-native species whose ecological roles and management in the context of forest regeneration are contested. In a restoration experiment at two 0.64 ha sites we quantified the response of native woody vegetation recruitment to (1) release from competition with introduced pasture grasses, and (2) local facilitation of frugivore-assisted seed dispersal provided by scattered woody plants and artificial bird perches. Herbicide pasture grass suppression during 20 months caused a significant but modest increase in density of native woody seedlings, together with abundant co-recruitment of the prominent non-native pioneer wild tobacco (Solanum mauritianum). Recruitment of native species was further enhanced by local structure in herbicide-treated areas, being consistently greater under live trees and dead non-native shrubs (herbicide-treated) than in open areas, and intermediate under bird perches. Native seedling recruitment comprised 28 species across 0.25 ha sampled but was dominated by two rainforest pioneers (Homalanthus novoguineensis, Polyscias murrayi). These early results are consistent with the expected increase in woody vegetation recruitment in response to release from competitive and dispersive barriers to rainforest regeneration. The findings highlight the need for a pragmatic consideration of the ecological roles of woody weeds and the potential roles of "new forests" more broadly in accelerating succession of humid tropical forest across large areas of retired agricultural land. © 2014 Elgar, Freebody, Pohlman, Shoo and Catterall.
Heise-Pavlov S.R.,Center for Rainforest Studies |
Longway L.J.,Bard College at Simon's Rock
Ecological Management and Restoration | Year: 2011
Cane Toads (Rhinella marina, formerly Bufo marinus) in restoration sites on the Atherton Tableland in NE Australia consumed invertebrates belonging to 11 different taxa with ants being the most abundant prey item. Principal component analyses showed that the composition of invertebrates in Cane Toad diet is largely a reflection of invertebrates found in pitfall and leaf litter samples suggesting that the species is an indiscriminant feeder. However, pitfall samples contained more Collembola and Isopoda than were found in Cane Toad stomachs. The Cane Toad may benefit from restoration management practices by utilizing food resources enhanced by mulching and providing microhabitats (e.g. rock piles, logs) as shelter. While further studies would be needed to test this practitioners working in areas where the Cane Toad is problematic may consider trade-offs between attracting invertebrates and Cane Toads by monitoring provided microhabitat features. © 2011 Ecological Society of Australia.
Maina J.,University of Queensland |
Kithiia J.,Center for Rainforest Studies |
Cinner J.,James Cook University |
Neale E.,Wildlife Conservation Society |
And 4 more authors.
Regional Environmental Change | Year: 2015
A major gap exists in integrating climate projections and social–ecological vulnerability analyses at scales that matter, which has affected local-scale adaptation planning and actions to date. We address this gap by providing a novel methodology that integrates information on: (i) the expected future climate, including climate-related extreme events, at the village level; (ii) an ecological assessment of the impacts of these climate forecasts on coral reefs; and (iii) the social adaptive capacity of the artisanal fishers, to create an integrated vulnerability assessment on coastal communities in five villages in Papua New Guinea. We show that, despite relatively proximate geographies, there are substantial differences in both the predicted extreme rainfall and temperature events and the social adaptive capacity among the five fishing-dependent communities, meaning that they have likely different vulnerabilities to future climate change. Our methodology shows that it is possible to capture social information and integrate this with climate and ecological modeling in ways that are best suited to address the impacts of climate-mediated environmental changes currently underway across different scales. © 2015 Springer-Verlag Berlin Heidelberg
Florentine S.K.,University of Vic |
Pohlman C.L.,Center for Rainforest Studies |
Westbrooke M.E.,University of Vic
Restoration Ecology | Year: 2016
A long-term rainforest restoration experiment was established on abandoned pasture in northeastern Queensland in 1993 to examine the effectiveness of five different restoration planting methods: (T1) control (no plantings); (T2) pioneer monoculture (planting seedlings of one pioneer species, Homalanthus novoguineensis, Euphorbiaceae); (T3) Homalanthus group framework method (H. novoguineensis and eight other pioneer species); (T4) Alphitonia group framework method (Alphitonia petriei, Rhamnaceae, with eight other pioneer species); and (T5) maximum diversity method (planting pioneers, middle-phase species, and mature-phase species). We investigated temporal patterns in the (1) fate of seedlings originally planted in 1993; (2) natural recruitment of native plant species; and (3) current habitat structure (canopy cover and ground cover of grasses and invasive plants) within each restoration treatment. A total of 97% of seedlings planted in T2 died within the first 13 years and all had died by 2014. A total of 72% of seedlings planted in T3, 55.5% of seedlings planted in T4, and 55% of seedlings planted in T5 also died by 2014. By 2014, 42 species from 21 families had recruited across the experimental site, and the abundance of recruits was almost twice that recorded in 2001 and 2006. Overall, T3, T4, and T5 had the greatest diversity and abundance of recruits. By 2014, canopy cover was greatest in T3, T4, and T5 but grass cover was least in T5. It is concluded that some restoration success measures increase with planting diversity, but overall the rate of recovery is similar in framework species and maximum diversity method. © 2016 Society for Ecological Restoration.
Berry Z.C.,Center for Rainforest Studies |
Wevill K.,Center for Rainforest Studies |
Curran T.J.,Center for Rainforest Studies
Weed Research | Year: 2011
The invasive weed, Lantana camara, dominates numerous tropical and sub-tropical ecosystems and affects many aspects of ecosystem functioning, one of them being susceptibility to fire intrusion. The process by which L. camara might alter fire regimes in dry rainforest was examined by considering two potential mechanisms: (i) by being more ignitable than native species or (ii) by altering the structure and distribution of biomass to facilitate fire spread. We hypothesised that L. camara might alter fire regimes by both mechanisms. Measurements of leaf dry matter content, twig dry matter content and burn durations in laboratory trials implied that L. camara was less ignitable than native dry rainforest species. Fuel bed depths, leaf litter depths, percentage cover by fuels and amount of medium-size class fuels were higher in dry rainforest invaded by L. camara than in non-invaded forests. This suggests that the mechanism by which L. camara alters the fire regime in dry rainforest is by shifting the distribution of available fuels closer to the ground and providing a more continuous fuel layer in the understory. Management should focus on targeting L. camara removal around forest edges adjacent to frequently burned savannas and in areas of high conservation value. © 2011 The Authors. Weed Research © 2011 European Weed Research Society.
Freeman A.N.D.,Center for Rainforest Studies
Australian Field Ornithology | Year: 2015
Secondary forests can assist in restoring ecosystems affected by habitat loss and fragmentation and may provide a cost-effective alternative to large-scale planting. In the Wet Tropics bioregion, abandoned farmland frequently develops successional forest dominated by Hickory Wattle Acacia celsa but there has been little research on its value to wildlife. We examined the bird communities of younger (17-25 years) and older (50+ years) Acacia-regrowth forests and compared them with those in contiguous cleared land and never-cleared rainforest over an 18-day period in November 2003 in one location on the Atherton Tablelands, Queensland. Cleared sites had the lowest bird species richness and contained a mix of grassland, eucalypt, mixed forest and rainforest-dependent species. Bird species richness was highest in the never-cleared forest. Cleared sites had significantly fewer mixed forest and rainforest-dependent bird species than never-cleared forest. In both regrowth age classes and in never-cleared forest, there were few grassland and eucalypt forest bird species and similar proportions of mixed forest and rainforest-dependent bird species. Cleared sites and younger regrowth had significantly fewer endemic bird species than never-cleared forest, and six rainforest-dependent species were not recorded in regrowth. Although regrowth as young as 17-25 years provides habitat for a range of rainforest species, even at 50+ years it may not support some rainforest species, including some regional endemics of conservation concern. © Australian Field Ornithology 2015.