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Abstract Lightning strikes are a common source of disturbance in tropical forests, and a typical strike generates large quantities of dead wood. Lightning‐damaged trees are a consistent resource for tropical saproxylic (i.e., dead wood‐dependent) organisms, but patterns of consumer colonization and succession following lightning strikes are not known. Here, we documented the occurrence of four common consumer taxa spanning multiple trophic levels—beetles,Aztecaants, termites, and fungi—in lightning strike sites and nearby undamaged control sites over time in a lowland forest of Panama. Beetle abundance was 10 times higher in lightning strike sites than in paired control sites, and beetle assemblages were compositionally distinct. Those in strike sites were initially dominated by bark and ambrosia beetles (Curculionidae: Platypodinae, Scolytinae); bark and ambrosia beetles, and predaceous taxa increased in abundance relatively synchronously. Beetle activity and fungal fruiting bodies, respectively, were 3.8 and 12.2 times more likely to be observed in lightning‐damaged trees in strike sites versus undamaged trees in paired control sites, whereas the occurrence probabilities ofAztecaants and termites were similar between damaged trees in lightning strike sites and undamaged trees in control sites. Tree size also was important; larger dead trees in strike sites were more likely to support beetles, termites, and fungal fruiting bodies, and larger trees—regardless of mortality status—were more likely to hostAzteca. Beetle presence was associated with higher rates of subsequent fungal presence, providing some evidence of beetle‐associated priority effects on colonization patterns. These results suggest that lightning plays a key role in supporting tropical insect and fungal consumers by providing localized patches of suitable habitat. Any climate‐driven changes in lightning frequency in tropical forests will likely affect a broad suite of consumer organisms, potentially altering ecosystem‐level processes.
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Termite Presence and Feeding on Loblolly Pine Wood Differs Among Four Root-Infecting Bluestain (ophiostomatoid) Fungal Species
Abstract Bark beetles and root weevils can impact forests through tree death on landscape scales. Recently, subterranean termites have been linked to these beetles via the presence of bluestain fungi (Ascomycota: Ophiostomataceae), which are vectored to trees by beetles. However, only a small subset of bluestain species have been examined. Here, we tested whether termite-bluestain association patterns in the field reflect termite feeding preference in laboratory choice trials. We documented the presence of four bluestain fungi (Leptographium procerum (W.B. Kendr.), L. terebrantis (Barras & Perry), Grosmannia huntii (Rob.-Jeffr.), and G. alacris (T.A. Duong, Z.W. de Beer & M.J. Wingf.) in the roots of 2,350 loblolly pine trees in the southeastern United States and whether termites were present or absent on these roots and paired this with laboratory choice feeding trials. Termites were found 2.5-fold on tree roots with at least one bluestain fungus present than tree roots without bluestain fungi. Although termites in this study and others were associated with L. procerum, L. terebrantis, and marginally G. huntii, termites only showed preferential feeding on wood inoculated with G. huntii in laboratory trials. This suggests that increased termite presence on wood with bluestain fungi may be driven by factors other than increased wood palatability. Termites could thus disproportionately affect wood turnover rates for specific pools (e.g., bark beetle and root weevil attacked trees) and in some cases (e.g., G. huntii) accelerate wood decomposition. This study supports the growing evidence that the association between subterranean termites and bluestain fungi is spatially and taxonomically widespread.
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- Award ID(s):
- 1660346
- PAR ID:
- 10295789
- Editor(s):
- Hajek, Ann
- Date Published:
- Journal Name:
- Environmental Entomology
- ISSN:
- 0046-225X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/ee/nvab052
