A plausible, but largely unexplored reason for many weed biocontrol agents failing to establish or being ineffective, could involve abiotically induced changes to an invasive plants' biochemical phenotype and consequent enhanced herbivore resistance. Considerable literature demonstrates that chemically altered plant phenotypes can impair insect life history performance. Heather beetle, (Lochmaea suturalis), introduced to control invasive heather (Calluna vulgaris) in New Zealand (NZ) was difficult to establish and displays variable effectiveness.
View Article and Find Full Text PDFOrganisms have evolved diverse strategies to manage parasite infections. Broadly, hosts may avoid infection by altering behaviour, resist infection by targeting parasites or tolerate infection by repairing associated damage. The effectiveness of a strategy depends on interactions between, for example, resource availability, parasite traits (virulence, life-history) and the host itself (nutritional status, immunopathology).
View Article and Find Full Text PDFTemperate heathlands and blanket bogs are globally rare and face growing wildfire threats. Ecosystem impacts differ between low and high severity fires, where severity reflects immediate fuel consumption. This study assessed factors influencing fire severity in Scottish heathlands and blanket bogs, including the efficacy of the Canadian Fire Weather Index System (CFWIS).
View Article and Find Full Text PDFGastrointestinal nematode (GIN) parasites play an important role in the ecological dynamics of many animal populations. Recent studies suggest that fine-scale spatial variation in GIN infection dynamics is important in wildlife systems, but the environmental drivers underlying this variation remain poorly understood. We used data from over two decades of GIN parasite egg counts, host space use, and spatial vegetation data from a long-term study of Soay sheep on St Kilda to test how spatial autocorrelation and vegetation in an individual's home range predict parasite burden across three age groups.
View Article and Find Full Text PDFEcological theory posits that temporal stability patterns in plant populations are associated with differences in species' ecological strategies. However, empirical evidence is lacking about which traits, or trade-offs, underlie species stability, especially across different biomes. We compiled a worldwide collection of long-term permanent vegetation records (greater than 7000 plots from 78 datasets) from a large range of habitats which we combined with existing trait databases.
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