Topographical variation reduces phenological mismatch between a butterfly and its nectar source

Abstract

The timing of many biological events, including butterfly imago emergence, has advanced under climate change, with the rate of these phenological changes often differing among taxonomic groups. Such inter-taxa variability can lead to phenological mismatches. For example, the timing of a butterfly's flight period may become misaligned with a key nectar resource, potentially increasing the extinction risk to both species. Here we fit statistical models to field data to determine how the phenology of the marbled white butterfly, Melanargia galathea, and its main nectar source, greater knapweed, Centaurea scabiosa, have changed over recent years at three sites across the UK. We also consider whether topographical diversity affects C. scabiosa's flowering period. At our focal site, on the species northern range limit, we find that over a 13year period the onset of C. scabiosa's flowering period has become later whilst there is no obvious trend over time in the onset of M. galathea's flight period. In recent years, butterflies have started to emerge before their key nectar source was available across most of the site. This raises the intriguing possibility that phenological mismatch could be an unrecognised determinant of range limits for some species. However, the presence of topographical diversity within the site decreased the chance of a mismatch occurring by increasing the length of the flowering period by up to 14 days. We suggest that topographical diversity could be an important component in minimising phenological mismatches under future climate change.

Mismatch managed? Phenological phase extension as a strategy to manage phenological asynchrony in plant–animal mutualisms

“…Recent evidence suggests that extended phenological timing can aid mutualisms (e.g. Frankie et al ; Hindle et al ; Mola & Williams ). Hence, increasing or maintaining availability of partner resources across time may support the survival of species in mutualistic interactions as the climate changes.…”

“…Heterogeneity in microclimates can yield lengthened duration by creating patterns of complementarity in the timing in both plant and animal activity. Abiotic gradients and habitat heterogeneity can impact the timing of both animal and plant species distributed across a site (Hindle et al ; Olliff‐Yang & Mesler ). Management to conserve, maintain, and restore abiotic heterogeneity, and increasing connectivity across heterogeneous landscapes could extend phenology at both local and landscape scales.…”

Developmental trap or demographic bonanza? Opposing consequences of earlier phenology in a changing climate for a multivoltine butterfly

“…Although climate change may provide longer thermal windows that bolster populations, these shifts may also result in unaccounted ecological costs early and late season (Potts et al, ; Warren et al, ), such as asynchrony among host (Bale et al, ; Forkner, Marquis, Lill, & Corff, ) and nectar (Doi, Gordo, & Katano, ; McKinney et al, ) plants. For example, earlier onset of butterfly emergence in the spring has advanced with climate change, but some nectar plants have remained unchanged (Hindle, Kerr, Richards, & Willis, ). Additionally, late generations might also experience lower availability and quality of host plants (Choi, Park, Park, Ryoo, & Lee, ).…”

Dynamic Models for Longitudinal Butterfly Data

“…Phenological studies have typically involved measures such as mean first encounter, mean peak encounter and mean length of the flight period (Roy and Sparks 2000;Diamond et al 2014;Karlsson 2014), which may be driven by observer behaviour. The improved estimates of phenology from dynamic models provide the opportunity to study linkages between changes in phenology and changes in abundance and productivity, for example phenological mismatch (Hindle et al 2015).…”