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Changes in phenology in response to ongoing climate change have been observed in numerous taxa around the world. Differing rates of phenological shifts across trophic levels have led to concerns that ecological interactions may become increasingly decoupled in time, with potential negative consequences for populations. Despite widespread evidence of phenological change and a broad body of supporting theory, large-scale multitaxa evidence for demographic consequences of phenological asynchrony remains elusive. Using data from a continental-scale bird-banding program, we assess the impact of phenological dynamics on avian breeding productivity in 41 species of migratory and resident North American birds breeding in and around forested areas. We find strong evidence for a phenological optimum where breeding productivity decreases in years with both particularly early or late phenology and when breeding occurs early or late relative to local vegetation phenology. Moreover, we demonstrate that landbird breeding phenology did not keep pace with shifts in the timing of vegetation green-up over a recent 18-y period, even though avian breeding phenology has tracked green-up with greater sensitivity than arrival for migratory species. Species whose breeding phenology more closely tracked green-up tend to migrate shorter distances (or are resident over the entire year) and breed earlier in the season. These results showcase the broadest-scale evidence yet of the demographic impacts of phenological change. Future climate change–associated phenological shifts will likely result in a decrease in breeding productivity for most species, given that bird breeding phenology is failing to keep pace with climate change.
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Widespread Mismatch Between Phenology and Climate in Human‐Dominated Landscapes
Abstract Plants track changing climate partly by shifting their phenology, the timing of recurring biological events. It is unknown whether these observed phenological shifts are sufficient to keep pace with rapid climate changes. Phenological mismatch, or the desynchronization between the timing of critical phenological events, has long been hypothesized but rarely quantified on a large scale. It is even less clear how human activities have contributed to this emergent phenological mismatch. In this study, we used remote sensing observations to systematically evaluate how plant phenological shifts have kept pace with warming trends at the continental scale. In particular, we developed a metric of spatial mismatch that connects empirical spatiotemporal data to ecological theory using the “velocity of change” approach. In northern mid‐to high‐latitude regions (between 30–70°N) over the last three decades (1981–2014), we found evidence of a widespread mismatch between land surface phenology and climate where isolines of phenology lag behind or move in the opposite direction to the isolines of climate. These mismatches were more pronounced in human‐dominated landscapes, suggesting a relationship between human activities and the desynchronization of phenology dynamics with climate variations. Results were corroborated with independent ground observations that indicate the mismatch of spring phenology increases with human population density for several plant species. This study reveals the possibility that not even some of the foremost responses in vegetation activity match the pace of recent warming. This systematic analysis of climate‐phenology mismatch has important implications for the sustainable management of vegetation in human‐dominated landscapes under climate change.
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- Award ID(s):
- 2045309
- PAR ID:
- 10362377
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- AGU Advances
- Volume:
- 2
- Issue:
- 4
- ISSN:
- 2576-604X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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