- Award ID(s):
- 1945136
- PAR ID:
- 10404777
- Date Published:
- Journal Name:
- Journal of the American Statistical Association
- ISSN:
- 0162-1459
- Page Range / eLocation ID:
- 1 to 11
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Fire disturbance in tropical savannas is integral to maintaining habitat heterogeneity and biodiversity, but its impact on avian species is highly variable. Savannas in northern Australia have recently been invaded by gamba grass (
Andropogon gayanus ), a perennial tussock grass that fuels late season fires at eight times the intensity of native vegetation. As gamba grass rapidly outcompetes native species and promotes more frequent and intense fires, it greatly decreases landscape heterogeneity and alters the effect of fire in tropical savannas. To investigate how a small passerine, the red‐backed fairywren (Malurus melanocephalus ), responds to fire disturbance and gamba grass cover, we studied their fine‐scale habitat use throughout the dry season before and after a high intensity fire. We used two spatially distinct approaches, radio‐telemetry and a transect‐based population census, to quantify fairywren habitat use at the group and population level, respectively. Radio‐telemetry and transect surveys revealed no direct mortality associated with the severe bushfire during the middle of the study season, suggesting fairywrens are resilient in the short‐term to fire disturbance. Our results indicate that fairywrens are largely flexible in their habitat use – instead of relocating after fire, they re‐centre their home range around the most photosynthetically productive habitats, dominated by saplings. While we found substantial variation in habitat use among social groups, red‐backed fairywren groups generally avoided dense habitat areas dominated by mature gamba grass. We conclude that red‐backed fairywrens are resilient to fire and flexible in their habitat use in the short‐term; however, in the long‐term, gamba grass may pose a threat to population viability. The importance of flexible behavioural strategies in tropical passerines will increase as fire regimes are exacerbated by invasive species and climate change. -
Degradation of most yeast mRNAs involves decapping by Dcp1/Dcp2. DEAD-box protein Dhh1 has been implicated as an activator of decapping, in coupling codon non-optimality to enhanced degradation, and as a translational repressor, but its functions in cells are incompletely understood. RNA-Seq analyses coupled with CAGE sequencing of all capped mRNAs revealed increased abundance of hundreds of mRNAs in
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