Impacts of local adaptation of forest trees on associations with herbivorous insects: implications for adaptive forest management

Abstract

Disruption of species interactions is a key issue in climate change biology. Interactions involving forest trees may be particularly vulnerable due to evolutionary rate limitations imposed by long generation times. One mitigation strategy for such impacts is Climate matching – the augmentation of local native tree populations by input from nonlocal populations currently experiencing predicted future climates. This strategy is controversial because of potential cascading impacts on locally adapted animal communities. We explored these impacts using abundance data for local native gallwasp herbivores sampled from 20 provenances of sessile oak (Quercus petraea) planted in a common garden trial. We hypothesized that non-native provenances would show (i) declining growth performance with increasing distance between provenance origin and trial site, and (ii) phenological differences to local oaks that increased with latitudinal differences between origin and trial site. Under a local adaptation hypothesis, we predicted declining gallwasp abundance with increasing phenological mismatch between native and climate-matched trees. Both hypotheses for oaks were supported. Provenance explained significant variation in gallwasp abundance, but no gall type showed the relationship between abundance and phenological mismatch predicted by a local adaptation hypothesis. Our results show that climate matching would have complex and variable impacts on oak gall communities.

Natural selection and neutral evolutionary processes contribute to genetic divergence in leaf traits across a precipitation gradient in the tropical oak Quercus oleoides

“…For this reason, we also applied generalized linear mixed models to test the effects of neutral genetic structure and climate of origin (i.e., index of moisture) on the genetic differentiation of functional traits. The matrix of pairwise neutral genetic differentiation was used as a random effect, and the index of moisture in the geographic locations of the source populations was included as a fixed factor in the models (see Sato & Kudoh, ; Sinclair et al., ; Stone, Nee, & Felsenstein, ; for similar approaches). The genetic differentiation in functional traits was included as the dependent variable.…”

The forgotten season: the impact of autumn phenology on a specialist insect herbivore community on oak

“…Such variation has been shown to be important for both spring generations of leaf miners and gall wasps, but also for autumn generations of gall wasps (Crawley & Akhteruzzaman, 1988;Mopper & Simberloff, 1995;Sinclair et al, 2015). Such variation has been shown to be important for both spring generations of leaf miners and gall wasps, but also for autumn generations of gall wasps (Crawley & Akhteruzzaman, 1988;Mopper & Simberloff, 1995;Sinclair et al, 2015).…”

“…Much research has thus addressed whether currently synchronised species interactions will stay synchronised in a warmer climate. The timing of budburst has proved to be important in determining the herbivore damage on host plants, but also in affecting the occurrence and abundance of herbivorous insects (Crawley & Akhteruzzaman, 1988;Mopper & Simberloff, 1995;Sinclair et al, 2015;Heimonen et al, 2017). The timing of budburst has proved to be important in determining the herbivore damage on host plants, but also in affecting the occurrence and abundance of herbivorous insects (Crawley & Akhteruzzaman, 1988;Mopper & Simberloff, 1995;Sinclair et al, 2015;Heimonen et al, 2017).…”

Integrating climate change and habitat fragmentation to identify candidate seed sources for ecological restoration

“…These can include (1) the potential for inter‐ and intra‐specific hybridization through pollen dispersal which could lead to heterosis (superiority of hybrid over pure stock) (Costa e Silva et al ), outbreeding depression caused by disruption of locally adapted gene combinations (Costa e Silva et al ), or off‐site genetic contamination (Potts et al ); and (2) the spread of wildings, weeds, diseases, or pathogens (Ricciardi & Simberloff ). Depending on scale, translocations may also have extended impacts on dependent organisms (Whitham et al ; Sinclair et al ). Byrne et al () and Weeks et al () provide decision trees to evaluate the likelihood of ecological and genetic risks to the surrounding native remnants.…”