Phenological sensitivity to temperature mediates herbivory

Abstract

Species interactions drive ecosystem processes and are a major focus of global change research. Among the most consequential interactions expected to shift with climate change are those between insect herbivores and plants, both of which are highly sensitive to temperature. Insect herbivores and their host plants display varying levels of synchrony that could be disrupted or enhanced by climate change, yet empirical data on changes in synchrony are lacking. Using evidence of herbivory on herbarium specimens collected from the northeastern United States and France from 1900 to 2015, we provide evidence that plant species with temperature‐sensitive phenologies experience higher levels of insect damage in warmer years, while less temperature‐sensitive, co‐occurring species do not. While herbivory might be mediated by interactions between warming and phenology through multiple pathways, we suggest that warming might lengthen growing seasons for phenologically sensitive plant species, exposing their leaves to herbivores for longer periods of time in warm years. We propose that elevated herbivory in warm years may represent a previously underappreciated cost to phenological tracking of climate change over longer timescales.

A global analysis of tree pests and emerging pest threats

“…Last, we note that future global change is likely to shift the regions available for pest colonization, and in some cases, could affect pests’ host breadths. Recent climate change has resulted in plant pests shifting poleward at a rate of, on average, 2.7 km/y ( 30 ), and if pests and plants track climate asynchronously ( 31 ), this is likely to expose many pests to novel hosts. The recent climate-induced expansion of mountain pine beetles ( Dendroctonus ponderosae ) into northern Alberta, for instance, has exposed jack pine ( Pinus banksiana ) to beetle attack ( 32 ) and potentially provides a corridor to other susceptible hosts in eastern North America.…”

Macrophenology: insights into the broad‐scale patterns, drivers, and consequences of phenology

“…Herbivory, which is frequently implicated as a range limit for plants, is highly dependent on leaf phenology. Meineke et al (2021) analyzed over a century of herbarium specimens to show that herbivory is higher in plant species with greater temperature sensitivity in warmer years. Plants with the ability to take advantage of a long growing season may therefore be exposed to increased herbivory.…”

Herbivory in a changing climate—Effects of plant genotype and experimentally induced variation in plant phenology on two summer‐active lepidopteran herbivores and one fungal pathogen

“…In response to such warmer temperatures, many organisms are expected to advance their spring phenology, and the rate of advance can differ among species (Kharouba et al, 2018 ; Thackeray et al, 2016 ). Such changes in phenology can influence the interaction strengths among species (Kharouba et al, 2018 ; Liu et al, 2011 ; Meineke et al, 2021 ). In producer‐consumer interactions, the quality of a living resource may change with its phenological stage (Barton et al, 2019 ), which could result in changes in resource quality in producer‐consumer relationships.…”

“…species (Kharouba et al, 2018;Thackeray et al, 2016). Such changes in phenology can influence the interaction strengths among species (Kharouba et al, 2018;Liu et al, 2011;Meineke et al, 2021).…”